Dissertations / Theses: 'Static Test'

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Siddiqui, Asher. "Capturing JUnit Behavior into Static Programs : Static Testing Framework." Thesis, Linnaeus University, School of Computer Science, Physics and Mathematics, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-5510.

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In this research paper, it evaluates the benefits achievable from static testing framework by analyzing and transforming the JUnit3.8 source code and static execution of transformed code. Static structure enables us to analyze the code statically during creation and execution of test cases. The concept of research is by now well established in static analysis and testing development. The research approach is also increasingly affecting the static testing process and such research oriented work has proved particularly valuable for those of us who want to understand the reflective behavior of JUnit3.8 Framework.

JUnit3.8 Framework uses Java Reflection API to invoke core functionality (test cases creation and execution) dynamically. However, Java Reflection API allows developers to access and modify structure and behavior of a program. Reflection provides flexible solution for creating test cases and controlling the execution of test cases. Java reflection helps to encapsulate test cases in a single object representing the test suite. It also helps to associate each test method with a test object. Where reflection is a powerful tool to perform potential operations, on the other hand, it limits static analysis. Static analysis tools often cannot work effectively with reflection.

In order to avoid the reflection, Static Testing Framework provides a static platform to analyze the JUnit3.8 source code and transform it into non-reflective version that emulates the dynamic behavior of JUnit3.8. The transformed source code has possible leverage to replace reflection with static code and does same things in an execution environment of Static Testing Framework that reflection does in JUnit3.8. More besides, the transformed code also enables execution environment of Static Testing Framework to run test methods statically. In order to measure the degree of efficiency, the implemented tool is evaluated. The evaluation of Static Testing Framework draws results for different Java projects and these statistical data is compared with JUnit3.8 results to measure the effectiveness of Static Testing Framework. As a result of evaluation, STF can be used for static creation and execution of test cases up to JUnit3.8 where test cases are not creating within a test class and where real definition of constructors is not required. These problems can be dealt as future work by introducing a middle layer to execute test fixtures for each test method and by generating test classes as per real definition of constructors.

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Karlsson, Henrik. "Limiting Transitive Closure for Static Regression Test Selection approaches." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-254951.

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In computer science and software development it is important to test software in order to ensure reliability. Regression testing in order to find potential faults introduced by software changes is key to assuring that the software is stable. This process may be time consuming, so in order to speed it up there are approaches which select a subset of relevant tests based on the software changes.In the field of regression test selection there are two main approaches, static approaches and dynamic approaches. These different kinds of approaches have different strengths and weaknesses, however the field is currently dominated by dynamic approaches as the performance of the static approaches lags behind severely. Ensuring that the correct approach types are used for the appropriate situations calls for improvement of static approaches.Regression test selection approaches uses transitive closure to select relevant tests. For any node in a directed graph, transitive closure is the set of all reachable nodes from the starting node. This thesis proposes a solution which attempts to lessen the performance gap by implementing a controlled limit to the transitive closure property of the main test selection algorithm. The aim of the limited transitive closure is to reduce the time taken to select tests, and to reduce the amount of superfluous tests selected.The results show that the limited transitivity property as implemented for this thesis did not improve the performance in a satisfactory way. Safety dropped severely. Since the runtime and precision improved, there is room for improvement in potential future research of the limited transitivity approach before it can readily be dismissed as an unviable approach.
Inom fälten datalogi och mjukvaruutveckling är det viktigt att testa mjukvara för att försäkra sig om att den fungerar som den ska. Att köra regressionstester för att hitta potentiella fel som introducerats av mjukvaruändringar är en nödvändighet för att garantera stabiliteten hos mjukvara. Regressionstestprocessen kan dock vara resursoch tidskrävande, vilket har lett till introduktionen av urval av tester som körs vid regressionstestning, s.k. regression test selection.Fältet regression test selection delas allmänt upp i två olika typer av metoder, statiska och dynamiska. De statiska och dynamiska metoderna har olika styrkor och svagheter, och bör därför i teorin användas baserat på vilken typ som bäst lämpar sig för syftet. Dock är det stora prestandaskillnader och därför används nästan bara de dynamiska metoderna.I detta examensarbete presenteras ett försök till att öka prestandan av de statiska metoderna genom att använda sig av en kontrollerad begränsning av transitivitetsaspekten inom huvudalgoritmen för urval av tester. Syftet med denna kontrollerade begränsning är tvådelad; både att minska körtiden för testurval, men också att minska antalet överflödiga tester i det slutgiltiga urvalet.Resultaten visar på att den metod som introducerats i detta examensarbete inte ökar prestandan på ett sådant sätt att det otvetydligt kan beskrivas som en förbättring. Jämfört med statiska metoder som inte använder sig av den begränsade transitivitetsaspekten så minskade säkerhet, men körtid och precision förbättrades. Detta innebär att det finns möjlighet till förbättring av den begränsade transitivitetsmetoden innan den helt kan anses vara en ogenomförbar och opraktisk lösning på problemet.

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Syal, Manan. "Static Learning for Problems in VLSI Test and Verification." Diss., Virginia Tech, 2005. http://hdl.handle.net/10919/28099.

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Static learning in the form of logic implications captures Boolean relationships between various gates in a circuit. In the past, logic implications have been applied in several areas of electronic design automation (EDA) including: test-pattern-generation, logic and fault simulation, fault diagnosis, logic optimization, etc. While logic implications have assisted in solving several EDA problems, their usefulness has not been fully explored. We believe that logic implications have not been carefully analyzed in the past, and this lack of thorough investigation has limited their applicability in solving hard EDA problems. In this dissertation, we offer deeper insights into the Boolean relationships exhibited in a circuit, and present techniques to extract their full potential in solving two hard problems in test and verification: (1) Efficient identification of sequentially untestable stuck-at faults, and (2) Equivalence checking of sequential circuits. Additionally, for the dissertation, we define a new concept called multi-cycle path delay faults (M-pdf) for latch based designs with multiple clock domains, and propose an implications-based methodology for the identification of untestable M-pdfs for such designs. One of the main bottlenecks in the efficiency of test-pattern-generation (TPG) is the presence of untestable faults in a design. State-of-the-art automatic test pattern generators (ATPG) spend a lot of effort (in both time and memory) targeting untestable faults before aborting on such faults, or, eventually identifying these faults as untestable (if given enough computational resources). In either case, TPG is considerably slowed down by the presence of untestable faults. Thus, efficient methods to identify untestable faults are desired. In this dissertation, we discuss a number of solutions that we have developed for the purpose of untestable fault identification. The techniques that we propose are fault-independent and explore properties associated with logic implications to derive conclusions about untestable faults. Experimental results for benchmark circuits show that our techniques achieve a significant increase in the number of untestable faults identified, at low memory and computational overhead. The second related problem that we address in this proposal is that of determining the equivalence of sequential circuits. During the design phase, hardware goes through several stages of optimizations (for area, speed, power, etc). Determining the functional correctness of the design after each optimization step by means of exhaustive simulation can be prohibitively expensive. An alternative to prove functional correctness of the optimized design is to determine the designâ s functional equivalence w.r.t. some golden model which is known to be functionally correct. Efficient techniques to perform this process, known as equivalence checking, have been investigated in the research community. However, equivalence checking of sequential circuits still remains a challenging problem. In an attempt to solve this problem, we propose a Boolean SAT (satisfiability) based framework that utilizes logic implications for the purpose of sequential equivalence checking. Finally, we define a new concept called multi-cycle path-delay faults (M-pdfs). Traditionally, path delay faults have been analyzed for flip-flop based designs over the boundary of a single clock cycle. However, path delay faults may span multiple clock cycles, and a technique is desired to model and analyze such path delay faults. This is especially essential for latch based designs with multiple clock domains, because the problem of identifying untestable faults is more complex in such design environments. In this dissertation, we propose a three-step methodology to identify untestable M-pdfs in latch-based designs with multiple clocks using logic implications.
Ph. D.

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Mendenhall, Scout. "Effect of Deposition from Static Test Fires on Corn and Alfalfa." DigitalCommons@USU, 2013. https://digitalcommons.usu.edu/etd/1404.

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A greenhouse study was conducted to determine the effects of deposition from static rocket test fires on corn and alfalfa. Seeds were germinated in a wide concentration range of depositional material, called test fire soil (TFS). Additionally, the impact of chloride and aluminum, two major components of test fire soil, on germination was also evaluated. Furthermore, plants were grown in packed columns and exposed to test fire soil, either in the root zone or on foliage. Tissue was weighed and analyzed to compare biomass production and plant composition. Corn and alfalfa exposed to test fire soil in the root zone produced less biomass than controls, but foliar treatment had no effect on biomass production. No kernels were produced by corn exposed to test fire soil in the root zone. Leaves of plants exposed to test fire soil in the root zone accumulated more metals and nutrients than controls, whereas plant tissue treated with test fire soil on the leaves contained only elevated levels of aluminum, although levels were still within reasonable concentrations for plants. Germination of seeds was not affected below 1% test fire soil in soil; however higher concentrations of test fire soil decreased percent germination. Addition of chloride to soil also inhibits germination, but addition of aluminum has no effect on germination percentage. Corn germination was restored in test fire soil leached with 200 mm artificial rainwater. The results of this research contribute information regarding the potential impact of test fire soil from static test fires on crop production. Test fire soil inhibits germination and growth if deposited in the root zone, and even foliar application alters tissue composition. However, plant composition is not altered significantly in terms of feed criteria, and germination can be restored by irrigating the TFS. The effects of test fire soil are attributed to high levels of chloride that induce salt stress. Crop damage may be avoided by conducting static test fires after crops are harvested or providing extra irrigation to soil impacted with the TFS.

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Sirichantra, Jayiyavadee. "Use of the quasi-static indentation test on measure toughness in composites." Thesis, University of Surrey, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.540963.

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Gustafson, Christopher, and Sam Florin. "Qualification of Tool for Static Code Analysis : Processes and Requirements for Approval of Static Code Analysis in the Aviation Industry." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-277941.

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In the aviation industry, the use of software development tools is not as easily adopted as in other industries. Due to the catastrophic consequences of software errors in airborne systems, software development processes has rigorous requirements. One of these requirements is that a code standard must be followed. Code standards are used to exclude code constructions which could result in unwanted behaviours. The process of manually ensuring a specific code standard can be costly. This process could be automated by a tool for static code analysis, however, this requires a formal qualification. This thesis evaluates the process of qualifying a tool for static code analysis in accordance with the requirements of the major aviation authorities EASA and FAA. To describe the qualification process, a literature study was conducted. To further explain how an existing tool could be put through the qualification process, a case study of the existing tool Parasoft C/C++ test was conducted. The results of the literature study show what processes must be completed in order to qualify a static code analysis tool. Importantly, the study shows that no requirements are put on the development process of the tool. This was an important takeaway as it meant that an existing tool could be qualified without any additional data from the developer of the tool. The case study of Parasoft C/C++ test showed how the tool could be configured and verified to analyze code in accordance with a small set of code rules. Furthermore, three documents including qualification data were produced showing how the qualification process should be documented in order to communicate the process to an authority. The results of the thesis do not provide the full picture of how a tool could be qualified as the software, in which the tool is used, is considerations the are specific to the software the tool is used to develop still need to be taken into consideration. The thesis does, however, provide guidance on the majority of the applicable requirements. Future research could be done to provide the complete picture of the qualification process, as well as how the process would look like for other types of tools.
Inom flygindustrin är användandet av olika programmeringsverktyg inte lika självklart som inom andra industrier. På grund av de katastrofala konsekvenser som fel i mjukvaran i ett flygplan kan resultera i finns det rigorösa krav på mjukvaruutvecklingsprocessen. Ett av dessa krav är att en viss kodstandard måste upprätthållas. Kodstandarder används för att exkludera vissa strukturer i kod som kan leda till oönskat beteende. Upprätthållandet av en viss kodstandard är en långdragen process att genomföra manuellt, och kan därför automatiseras med hjälp av ett statiskt kodanalysverktyg. För att kunna använda ett sådant verktyg behövs däremot en formell verktygskvalificering. I denna uppsats kommer kvalificeringsprocessen av ett verktyg för statisk kodanalys att evalueras enligt de krav som de två stora flygmyndigheterna EASA och FAA ställer. För att förklara processen av att kvalificera ett sådant verktyg gjordes en litteraturstudie följt av en fallstudie av det existerande verktyget Parasoft C/C++ test. Resultaten av litteraturstudien beskriver de olika processerna som måste genomföras för att kvalificera ett statiskt kodanalysverktyg. Noterbart är att resultaten visar att inga krav ställs på utvecklingsprocessen av verktyget själv. Detta betyder att ett existerande kommersiellt verktyg kan kvalificeras utan att verktygsutvecklarna själva behöver bidra med extra information. Fallstudien visade hur verktyget Parasoft C/C++ test kan konfigureras och verifieras att följa en viss kodstandard. Vidare resulterade fallstudien i utkast av de nödvändiga dokumenten som behöver produceras för att kommunicera kvalificeringsprocessen till en myndighet. De resultat som presenteras i denna uppsats är i sig inte tillräckliga för beskriva hela kvalificeringsprocessen. Ytterligare överväganden som är specifika till den mjukvaran som verktyget ska användas till att utveckla måste göras för att en komplett kvalificering ska kunna genomföras. Uppsatsen bidrar däremot med riktlinjer och vägledning av majoriteten av de processerna som behöver genomföras. Ytterligare forskning kan göras för att bidra med den kompletta bilden av verktygskvalificering av ett statiskt kodanalysverktyg, samt hur kvalificering kan göras av andra typer av verktyg.

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Niazi, Fawad Sulaman. "Static axial pile foundation response using seismic piezocone data." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/52195.

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Ever since the use of cone penetration testing (CPT) in geotechnical site investigations, efforts have been made to correlate its readings with the components of static axial pile capacity: unit base resistance (qb) and unit shaft resistance (fp). Broadly, the pile capacity analysis from CPT data can be accomplished via two main approaches: rational (or indirect) methods, and direct methods. The rational methods require a two-step approach, whereby CPT data are first used to provide assessments of geoparameters that are further utilized as input values within a selected analytical framework to enable the evaluation of the pile capacity components. In contrast, direct CPT methods use the measured penetrometer readings by scaling relationships or algorithms in a single-step process to obtain fp and qb for full-size piling foundations. The evolution of the CPT from mechanical to electrical to electronic versions and single-channel readings (i.e., measured tip resistance, qc) to the piezocone penetration test (CPTu), that provides three readings of point stress (qt), sleeve friction (fs), and porewater pressure (u1 or u2), has resulted in the concurrent development of multiple CPT-based geotechnical pile design methods. It is noted, however, that current CPT-based methods focus only on an estimate of "axial pile capacity", corresponding to a limiting load or force at full mobilization. A more comprehensive approach is sought herein utilizing the CPT readings towards producing a complete nonlinear load-displacement-capacity (Q-w-Qcap) on axial pile response. In particular, the seismic cone penetration test (SCPT) provides the profile of shear wave velocity (Vs) that determines the fundamental small-strain shear modulus: Gmax = gt?Vs2, where gt = total mass density of soil. With the penetrometer readings useful in assessing foundation capacity, the stiffness Gmax finds application within elastic continuum solutions towards evaluating the load-displacement (Q-w) response. In this study, a concise review of the deep foundation systems is presented, including pile types and characteristics, various arrangements of axial pile load testing in static mode, and interpretations of the load test data. In addition a comprehensive state-of-the-art review of CPT-based rational and direct methods of pile capacity evaluations is compiled. It is recognized that the direct methods offer more convenience in their straightforward approach in estimation of the pile capacity. The piezocone-based UniCone direct method proposed by Eslami and Fellenius (1997) is selected for further refinements, as it utilizes all three CPT readings in its design formulations. Concerning the analysis of pile deformations under axial loading, a brief review covers designs employing empirical formulations, analytical solutions, load-transfer (t-z) methods, numerical simulations, variational approaches, and those using hybrid methods. Specifically, the analytical elastic solution by Randolph and Wroth (1978; 1979) is covered in more detail since it is simple and convenient in application with extended applications to uplift and bidirectional O-cell types of loadings. This elastic approach also serves well in modeling a stacked pile solution for layered soil profiles. The last part of the review covers various shear modulus reduction schemes, since evaluation of the applicable stiffnesses is considered to be the most delicate phase in the nonlinear Q-w response analysis of axially loaded piles. It is identified that the most appropriate scheme applicable to static axial loading of pile foundations is the one that can be derived from the back-analyses of actual load tests within the framework of analytical elastic solution. In order to conduct a comprehensive research study on the axial Q-w-Qcap response of deep foundations from CPT readings, a large database is compiled. This includes 330 case records of pile load tests at 70 sites from 5 continents and 19 different countries of the world, where pile foundations were load tested under top-down compression or top-applied uplift (tension) loading, or both, or by bi-directional Osterberg cell setups. All test sites had been investigated using CPT soundings; in most cases by the preferred SCPTu that provides all four readings from the same sounding: qt, fs, u2, and Vs. In a few cases, sites were subjected to CPT or CPTu and the profiles of shear wave velocities were obtained by other field geophysical techniques, otherwise by empirical estimations. Results of the new correlation efforts are offered to derive coefficients Cse for shaft component and Cte for base component of the axial pile capacity from CPTu data. The UniCone type of soil classification chart is refined by delineating 11 soil sub-zones along with their respective Cse, in contrast to the 5 zones originally proposed. The CPT material index, Ic (Robertson, 2009) is then used to establish direct correlations linking Cse vs. Ic and Cte vs. Ic. Statistical relationships offer continuous functions for estimating the coefficients over a wide range of Ic values, thereby eliminating the need for use of the soil classification chart as well as improving the reliability in the evaluations of fp and qb. The effects of the pile loading direction (compression vs. uplift) and loading rate are also incorporated in the proposed design formulations. New sets of shear stiffness reduction curves are developed from the back-analysis of pile load tests and Gmax profiles obtained from the SCPT data. Alternative functions formats are provided in terms of hyperbolic tangent expressions or exponential curves, developed as normalized shear stiffness (G/Gmax) vs. logarithm of percent pseudo-strain (gp = w/d, where w = pile displacement and d = pile diameter). These charts offer convenience in the axial Q-w analysis of different pile categories within the framework of analytical elastic solution. The results also account for the plasticity characteristics of the soil formations within the database. A stacked pile model for Q-w analysis is presented in which certain adaptations are proposed in the elastic continuum solution. These adaptations enable plotting of separate modulus reduction curves (G/Gmax vs. gp) as function of depth for each layer, and treating pile as a stack of smaller pile segments embedded in a multi-layered soil media. The solution can be used to address the question of progressive failure with depth in a multi-layer soil media that exhibits nonlinear soil stiffness response. Finally, the closed-from analytical elastic pile solution for predicting the Q-w response is decoupled and modified to account for different setup cases and multi-stage loading of bi-directional O-cell tests. The decoupling accounts for separate assessments of the response to axial loading for different segments of pile shaft and different stages of loading, while the modifications include: (1) reduced maximum radius of influence for the upward displacements of the upper shaft segment, and (2) modeling the non-linear ground stiffness from the back-analysis of a well-documented dataset of O-cell load tests.

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Christensen, Dustin Shaun. "Full Scale Static Lateral Load Test of a 9 Pile Group in Sand." Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1267.pdf.

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Lu, Dandan, and 卢丹丹. "Effects of static pile penetration on an adjacent earth retaining structure." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B47054670.

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Tam, Weng On. "Development and use of static creep test to evaluate rut resistance of superpave mixes /." Digital version accessible at:, 1999. http://wwwlib.umi.com/cr/utexas/main.

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Tsiligiannis, Georgios. "Soft Errors in Memory Devices : Novel Methods and Practices for Dynamic and Static Testing." Thesis, Montpellier 2, 2014. http://www.theses.fr/2014MON20241.

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La plupart des environnements naturels et artificiels présentent du rayonnement ionisant (RI) interagissant avec l'électronique. Les effets du RI sont étudies depuis longtemps surtout pour des applications de critiques et de sécurité dans le domaine de l'espace, nucléaire, militaire et médical. L'étude des effets de rayonnement sur les appareils électroniques est complexe et demande la combinaison d'une connaissance pluridisciplinaire allant de la physique nucléaire à l'architecture à haut niveau, l'électronique et la science de matériaux. La réduction de la taille des transistors et l'augmentation simultanée de la complexité des systèmes contribuent à rendre plus critiques les problématiques. En occupant la plus grande surface de systèmes sur puce, les mémoires électroniques représentent la source principale des fautes induits par la radiation. Par conséquent, la compréhension des effets du rayonnement ionisant sur les mémoires et leur atténuation sont essentielles. Ces travaux de thèse introduisent des nouvelles méthodes de test à niveau de simulation et expérimental. En particulier, à niveau de simulation, est proposée une méthodologie pour l'estimation du taux de soft erreurs (SER) des circuits électroniques. Cette méthode prend en compte les variations environnementales et paramétriques des circuits pendant leur exposition au rayonnement ionisant. La méthode est évaluée à travers le cas d'étude représentée par une cellule SRAM de technologie 40nm interagissant avec des neutrons atmosphériques. Au niveau expérimental, des nouvelles méthodes pour le test sous accélérateur de SRAMs sont présentées, tout en mettant l'accent sur les défaillances que le test dynamique peut révéler. Les méthodes proposées s'appuient sur les algorithmes de type March et des séquences d'adressage spécifique des mémoires. Le choix des méthodes des tests dynamiques plutôt que des tests statiques est justifié par leur capacité de sensibiliser les effets électriques et du fait qu'ils sont très représentatifs du comportement réel des mémoires de vrais systèmes électroniques. Dans ces études, sont analyses en détail des évènements de large échelle qui apparaissent pendant les tests en accélérateurs et qui menaient à des MCUs (Multiple Cell Upsets), des effets singuliers permanent SEL (Single Event Latchups) et des effets singuliers de type SEFI (Single Event Functional Interrupt). Les protons à basses menaçant les technologies le plus récentes, donc, ici, leur contribution aux effets singuliers est aussi étudiée toujours en appliquant les nouvelles méthodes des tests proposés. Avec l'expérience acquise pendant les tests accélérés, un capteur des Hadrons à Haute Energie a été proposé et par la suite testé sur le faisceau de la structure H4IRRAD du CERN. La fonction principale de ce moniteur est basée sur l'extraction de la fluence des hadrons en tant qu'une fonction des effets singuliers SEU enregistrés. En outre, sont également présentés les résultats d'un test en temps réel fait à la station Concordia en Antarctique. Dans ce cas, l'instrument de détection était une version modifié du précédent capteur. Les résultats récoltés ont démontré que cet instrument de détection peut être utilisé dans des environnements et des conditions de rayonnement diverses. Enfin, des technologies de mémoire émergeantes ont été évaluées par rapport à leur réponse au rayonnement ionisant
Most of the known natural and artificial environments present ionizing radiation interacting with electronics. The effects of ionizing radiation have been a concern for many years especially for safety and critical applications such as space, nuclear, avionics, military and medical. The study of radiation effects on electronic devices is complex and requires the combination of multidisciplinary knowledge from nuclear physics to high-level system design, electronics and science of materials. The downscaling of the transistor size and the concurrent increase of systems' complexity contributes to worsen this problematic.By occupying the largest area of Systems on Chip, electronic memories represent the biggest source of radiation induced failures. Consequently, the understanding of ionizing radiation effects on memory devices and their mitigation is crucial. This thesis introduces novel test methods for both the simulation and the experimental level. More specifically, at the simulation level a framework is proposed for the estimation of the Soft Error Rate of electronic devices. This framework considers environmental and parametric variations of the device, while subjected to ionizing radiation. The framework is evaluated by considering the case study of a 40nm SRAM cell interacting with atmospheric neutrons. At the experimental level, novel methods for the accelerated testing of SRAM devices are presented, emphasizing to the failures that dynamic mode testing is able to reveal. These proposed methods are based on March algorithms in combination with specific addressing schemes for the memories.The choice to focus on dynamic testing methods is justified by their capability to sensitize electric effects that static mode testing is not able to do, and because they are highly representative of the realistic behavior of memories in actual electronic systems. Large scale events occurring during accelerated testing as a result of Multiple Cell Upsets, Single Event Latchups and Single Event Functional Interrupts are thoroughly analyzed. With low energy protons posing a threat for latest technologies, their contribution to Soft Errors is also studied by applying the proposed testing methods. Using the experience acquired from accelerated testing, a monitor for the sensing of the High Energy Hadrons was proposed and next tested at H4IRRAD beam line (CERN). The main functionality of this monitor is based on the extraction of the hadrons fluence as a function of the recorded Single Event Upsets. Furthermore, the results from a real-time test at the Concordia station in Antarctica are also presented. This time the sensing instrument was a customized version of the previous monitor and the retrieved results proved the usability of the instrument under different radiation environments and conditions. Finally emerging memory technologies are assessed for their response under ionizing radiation

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Hugoh, Albin. "Modeling of a Gear Test Rig : An Investigation of Static Loads and Dynamic Excitation of Vibrations." Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-74331.

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Today the automotive industry is going through big changes and facing many new challenges due to the transformation to a sustainable transport solution in combination with tougher legal demands. Gears have been around for a long time and it is one of the most efficient ways of transferring rotary motion from one shaft to another. Transmissions is a key factor in order to transfer the rotary motion from the engine to the wheels. Both traditional combustion engines and electric powered vehicles needs a transmission with gears. The continuously increasing demands on efficiency, noise and durability requires increased knowledge about gears, especially about gear dynamics and how vibrations are excited and transferred to the gearbox for different mesh frequencies. In this report, a theoretical background about gears is presented as well as the mechanisms behind the excitation of vibrations. The goal with this master thesis has been to create a validated model of a gear test rig. For the static validation, two types of gears have been used in the test gearbox. The gears in question are FZG standardized type-A gears and type-C gears. The model includes gears, shafts, bearings and housings. This model has been used for simulating static torque fluctuations as well as dynamic excitation of vibrations that is transferred to the housings, both at constant speed and with continuously increasing speed. In the dynamic analysis, only type-C gears have been used. To validate the model, vibrations have been measured on a FZG gear test rig using accelerometers and tachometer. For the static validation, torque has been measured while running the test rig at 5 rpm. The results show that it is possible to get the load clutch in the model to behave as in the test rig. It also shows that the model can register the static torque fluctuations similar to the fluctuations in the test rig. The type-C gears are better suited for the simulations and gives a better result than the type-A gears. For the type-A gears there are some numerical problems related to tip contact during meshing. The investigation of the tooth contact pressure pattern shows a good correlation between the simulations and the used type-C gear. The patterns have the same shape on the tooth flank which indicates that the contact between the teeth behave similar in the model and the test rig. For the validation of the dynamic behaviour, the gear mesh overtones have been investigated, both at constant velocity and with continuously increasing velocity. For the simulations, there are some issues related to the FEprobes placed on the gearboxes so instead the data from the inner bearings in the model have been used for the validation. The analysis of the dynamic simulations shows that it is possible to identify the tooth mesh overtones but the resonance peaks are less amplified compared to the measurements from the test rig. For the simulations with constant velocity the overtone trend correlates well with the experimental data at high speeds but at lower speed there is an amplitude peak for the firstovertone that doesn’t correlates with the measurements. As a conclusion, the model has beenstatically validated with good results while for the dynamic validation, there is still some aspects that need to be improved in order to get a good correlation between the simulations and the measurements from the test rig. Improvements suggested is to run the simulation with continuously increasing speed using more time steps in order to get more data points for the rpm spectra. It is also suggested to perform an impact hammer modal testing on the test rig in order to get a better understanding of the damping in the system.
Idag genomgår fordonsindustrin stora förändringar och står inför många nya utmaningar på grund av omställningen till en hållbar transportlösning i kombination med hårdare lagkrav. Kugghjul har funnits under en lång tid och är ett av de mest effektiva sätten att överföra rotationsrörelse från en axel till en annan. Transmissioner är en nyckelfaktor för att kunna överföra rotationsrörelse från motorn till hjulen. Både traditionella förbränningsmotorer och eldrivna fordon behöver en transmission med kugghjul. De ökande kraven gällande verkningsgrad, ljud och hållbarhet kräver mer kunskap om kugghjul, speciellt gällande kugghjulsdynamik och hur vibrationer exciteras och förs över till växellådshuset för olika kuggingreppsfrekvenser. I den här rapporten presenteras en teoretisk bakgrund om kugghjul och mekanismer som orsakar excitation av vibrationer. Målet med det här examensarbetet har varit att skapa en validerad modell av en testrigg för kugghjul. För den statiska valideringen har två typer av kugghjul använts i testväxellådan. Kugghjulen i fråga är FZG standardiserade typ-A och typ-C kugghjul. Modellen består av kugghjul, axlar, rullager och växellådshus. Modellen har använts för att simulera statiska vridmomentsfluktuationer och dynamisk excitation av vibrationer som överförs till växellådshusen, både vid konstant hastighet och för kontinuerligt ökande hastighet. I den dynamiska analysen har enbart typ-C kugghul använts. För att validera modellen har vibrationer mätts i en FZG testrigg för kugghjul genom att använda accelerometrar och takometer. För den statiska valideringen har vridmomentet mätts medans testriggen kördes med en hastighet av 5 rpm. Resultatet visar att det är möjligt att få lastkopplingen i modellen att bete sig som i testriggen. De visar också att modellen kan registrera statiska vridmomentsfluktuationer på ett liknande sätt som i testriggen. Typ-C kugghjulen är bättre lämpade för simuleringarna och ger ett bättre resultat än typ-A kugghjulen. För typ-A kugghjulen är det numeriska problem som är relaterade till toppkontakt under kuggingrepp. Undersökningen av tandkontaktsmönstret visar på god överensstämmelse mellan simulering och det använda typ-C kugghjulet. Kontaktmönstret har samma form på kuggflanken vilket indikerar att kontakten mellan tänderna sker på samma sätt i modellen som det gör i testriggen. För valideringen av det dynamiska beteendet har övertonerna för kuggingrepp undersökts, både vid konstant hastighet och för kontinuerligt ökande hastighet. För simuleringarna är det vissa problem relaterade till FEprobes som är placerade på växellådshusen så istället har data från de inre rullagren använts för validering. Analysen av de dynamiska simuleringarna visar att det är möjligt att identifiera kuggingreppsövertonerna men resonanspikarna är mindre förstärkta jämfört med mätdata från testriggen. För simuleringarna med konstant hastighet överensstämmer trenden för övertonerna väl med experimentella data vid höga hastigheter men vid lägre hastigheter är det en amplitudspik för den första övertonen som inte överensstämmer med mätningarna. Som slutsats så är modellen statiskt validerad med goda resultat medans för den dynamiska valideringen är det fortfarande vissa aspekter som behöver förbättras för att få en bättre överensstämmelse mellan simuleringar och mätningar från testriggen. Föreslagna förbättringar är att köra simuleringarna med kontinuerligt ökande hastighet med fler tidssteg för att få fler datapunkter för varvtalsspektrumet. Det föreslås också att genomföra ett knacktest på testriggen för att få en ökad förståelse om dämpningen i systemet.

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13

Wilson, Zachary David. "Flight Test Data System for Strain Measurement." DigitalCommons@CalPoly, 2019. https://digitalcommons.calpoly.edu/theses/2121.

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This thesis describes the design and evaluation of two devices to be included in the next generation of the family of devices called the Boundary Layer Data System (BLDS). The first device, called the Quasi-Static Strain Data Acquisition System, is a continuation of the BLDS-M series of devices to be known as the Flight Test Data System (FTDS) that uses a modular approach to acquire non-flow, quasi-static mechanical strain measurements. Various breakout boards and development boards were used to synthesize the device, which were housed by a custom PCB board. The system is controlled by the SimbleeTM System on a Chip (SOC), and strain measurements are acquired using the HX711 analog-to-digital converter (ADC), and acceleration measurements are acquired with the ADXL345 accelerometer. The Arduino IDE was used to program and troubleshoot the device. The second device, called the Dynamic Strain Data Acquisition System, is a laboratory proof-of-concept device that evaluates various methods of acquiring dynamic strain measurements that may be used in future FTDS designs. A custom PCB board was designed that houses the microcontroller and the various passive components and ICs used to acquire and store strain measurements. The system is controlled by the Atxmega128A4U microcontroller, and measurements are acquired using the AD7708 external ADC and the on-board ADC of the microcontroller. Atmel StudioTM was used to program the microcontroller in C/C++ and to troubleshoot the device. Both devices were tested extensively under room temperature and low temperature conditions to prove the reliability and survivability of each device. The quasi-static data acquisition system was validated to acquire and store measurements to a microSD card at 10 Hz, with a peak operating current under 60 mA. The dynamic data acquisition system was proven to acquire a thousand measurements at 1 kHz and store the data to a microSD card, with a peak operating current under 60 mA.

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14

Silva, Elisângela Pereira da. "Avaliação da Aderência em Estruturas Tubulares Metálicas Revestidas com Material Cimentício sob Esforços estáticos e dinâmicos." Universidade Federal da Paraíba, 2010. http://tede.biblioteca.ufpb.br:8080/handle/tede/5425.

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Made available in DSpace on 2015-05-08T15:00:10Z (GMT). No. of bitstreams: 1 parte1.pdf: 2464209 bytes, checksum: 983291ff02a154d08eaacd514bfd9d61 (MD5) Previous issue date: 2010-03-26
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
The bond on tubular steel coated with cementitious material, such as oil wells is quite complex. These are subject to change in temperature, pumping, steam injection, vibration caused by explosive charges, which can harm the interface of the tube cement paste through the loss of bond. Pullout tests in the laboratory are used for verification of the bond. However, this technique does not contemplate the life of the structural integrity of the well. This work aimed to contribute to the improvement of the technical verification of the bond through static and dynamic loading. For this, first using pullout tests has been proposed a study to test an improved speed of application loading. For this we used tubes coated partially of cement paste. Simulating the two contact conditions: no treatment on the surface of the tubes, and treatment with NaCl. It was observed that the presence of NaCl and a slower rate of load application positively influenced the bond stress. For the quasi-static dynamic test, by counting the number of cycles, it was felt that this substance in the interface showed a greater number of cycles. Thus it was concluded that this technique is feasible to evaluate the useful life of the well oil.
A aderência em estruturas tubulares metálicas revestidas com material cimentício, tais como, poço de petróleo é bastante complexa. Estes estão sujeitos a variação de temperatura, bombeamento, injeção de vapor, vibrações provocadas por cargas explosivas, que podem vir a prejudicar a interface do conjunto tubo-pasta de cimento, através da perda da aderência. Ensaios de arrancamento em laboratório são utilizados para verificação desta aderência. No entanto, esta técnica não contempla a vida útil da integridade estrutural do poço. O presente trabalho tem como objetivo contribuir para o aperfeiçoamento da técnica de verificação da aderência através de carregamento estático e dinâmico. Para isto, utilizou-se primeiro testes de arrancamento para verificação de uma melhor velocidade de aplicação de carga. Para isto utilizou-se tubos metálicos revestidos parcialmente por pasta de cimento. Simulou-se duas condições de contato: sem tratamento na superfície dos tubos, e com tratamento NaCl. Observou-se que a presença do NaCl e uma menor velocidade de aplicação de carga influenciaram de forma positiva a tensão de aderência. Para o ensaio dinâmico quase estático, através da contagem do número de ciclos, percebeu-se que a presença desta substância na interface apresentou um maior número de ciclos. Desta forma concluiu-se que esta técnica é viável para avaliação da vida útil do poço de petróleo.

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15

Davis, Thomas L. Davis. "Development and Characterization of a UAS Propulsion Test Bench." Kent State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=kent152573490048759.

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16

Algassem, Omar. "Parameters Affecting the Blast Performance of High Strength Fibre Reinforced Concrete Beams." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/35022.

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A limited number of studies have been conducted in the literature in order to investigate the behaviour of high-strength fibre-reinforced concrete (HSFRC) structural components subjected to blast loads. This study summarizes the results of a research program investigating the potential of using steel fibres to improve the blast performance of high-strength reinforced concrete beams. As part of the experimental investigation twenty beams were tested, including nine beams tested under static four-point bending, and eleven beams tested under dynamic blast loads using a shock-tube. Parameters considered in the study include the effect of concrete strength, steel fibres, fibre content, fibre type, longitudinal reinforcement ratio, and presence of shear reinforcement. All beams in the study have identical dimensions, with a cross-section of 125 x 250 mm and length of 2440 mm. To manufacture the specimens, two beams were cast with normal-strength self-consolidate concrete (SCC), with a specified strength of 50 MPa, while the remaining beams were cast with either plain or fibre-reinforced high-strength concrete having a compressive strength which varied between 95-110 MPa. The steel fibre content in the HSFRC beams varied between 0.5 and 1.0%, by volume of concrete. To investigate the effect of reinforcement ratio (ρ), the beams were reinforced with 2-#4 (American size) bars, 2-15M bars or 2-20M bars (ρ = 1.02%, 1.59%, and 2.41%, respectively). The majority of the plain concrete beams had transverse reinforcement which consisted of 6 mm stirrups arranged at a spacing of 100 mm in the shear spans, while most of the HSFRC beams were built without stirrups. The results indicate that all the parameters in this study (reinforcement ratio, presence of stirrups, concrete strength, steel fibres, fibre content and fibre type) affected the static and blast response of the beams, however, the results demonstrate that steel fibres have a more remarkable effect when compared to the other parameters. The provision of fibres is found to improve the blast performance of the HSC beams by increasing shear capacity, reducing maximum and residual mid-span displacements, reducing blast fragments and increasing damage tolerance.

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17

Rucker, Timothy A. "Dynamic Warm-Up Improves Mean Power Output Compared to a Warm-Up With Static Stretching." Ohio University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1320856261.

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18

Louati, Haithem. "Experimental and numerical study of humid granular material : influence of liquid content in quasi-static regime." Thesis, Ecole nationale des Mines d'Albi-Carmaux, 2016. http://www.theses.fr/2016EMAC0008/document.

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Cette thèse est une étude expérimentale et numérique du comportement au cisaillement de milieu granulaire humide sous l’effet de la quantité de liquide introduite et la contrainte normale appliquée. Les expériences ont été faites sur une cellule de cisaillement annulaire, pour une large gamme de contraintes appliquées allant de presque 0.3 kPa à 12 kPa. Les résultats donnent la variation de la contrainte de cisaillement en régime stationnaire en fonction de la contrainte normale pour une large variation de la quantité de liquide. Le liquide dans le milieu granulaire va de ponts liquides formés au point de contact jusqu’au remplissage totale de l'espace entre les grains. L’effet de liquide sur la résistance au cisaillement et la porosité de milieu granulaire a été analysé. Différents régimes du comportement de milieu granulaire humide ont été identifiés. Afin d’acquérir une compréhension microscopique du comportement au cisaillement de milieu granulaire sec et partiellement humide, la méthode des éléments discrets (DEM) a été utilisée. Des billes de verre de grande taille (2 mm de diamètre) ont été utilisées pour réduire le temps de simulation et faciliter la caractérisation à l’échelle de particule. Une première partie a été consacrée à l’étude de l’effet des propriétés microscopiques de particule (Module de Young et la friction de glissement) sur les propriétés macroscopiques de milieu granulaire sec et humide (le nombre de coordination, la porosité, le ratio de contraintes et la vitesse de particules). Une deuxième partie a été concernée par l’étude du comportement au cisaillement de milieu granulaire humide pour différentes fractions de liquide et différentes contraintes normales appliquées. En particulier, les forces capillaires et le nombre de ponts liquide ont été quantitativement analysés
We study experimentally and numerically the shear behaviour of wet granular material. We investigate the effect of the liquid content and the applied normal stresses to this behaviour. An annular shear cell was used to carry out the experiments, for a large range of applied normal stress from about 0.3 kPa to 12 kPa. The results give the variation of the shear stress at steady-state as a function of the normal stress for a wide range of liquid fraction. The incorporated liquid goes from forming bridges at the contact point to completely filling the space between grains. The shear resistance and the voidage fraction variations with the liquid fraction were analysed. Depending on the applied normal stress and the liquid fraction, different regimes of the shear resistance were identified. The discrete element method (DEM) was used to gain a microscopic understanding of the shear behaviour of dry and partially wet granular material in the shear cell. Large size glass beads were used to speed up the computational time and to facilitate characterisation at the particle scale. First, the influence of the microscopic properties of the particle (The Young’s modulus and the sliding friction) on the macroscopic properties of dry and wet granular materials (the coordination number, the voidage fraction, the shear ratio and the velocity of particles) was investigated. Secondly, the shear behaviour of the partially wet granular material for different liquid fractions and normal stresses was studied. The capillary forces and the number of liquid bridges were quantitatively analysed

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19

Shuchan, Pu. "Evaluation of non-destructive test methods for predicting the static bending stiffness and strength properties of thermally modified timber." Thesis, Linnéuniversitetet, Institutionen för skog och träteknik (SOT), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-66829.

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Non-destructive technologies have been applied on predicting the stiffness and strength properties of timber for decades. However, these technologies have rarely been investigated on predicting the properties of thermally modified timber. This study was performed to investigate the non-destructive technologies on estimating of the strength and stiffness properties of thermally modified timber. The material that was utilized for study is full-size structural Norway spruce. Twenty-five thermally modified boards were investigated by applying both non-destructive technologies and static bending test; 25 unmodified boards were used as a control group. Timber grader MTG and Sylvatest Trio are two non-destructive tools that were used for the determining the modulus of elasticity (MOE): MTG is an application of resonance frequency technology and Sylvatest Trio is an application of time-of-flight technology (TOF). The results show that both non-destructive technologies provide good results (??2=0.70 from MTG and??2=0.58 from Sylvatest Trio) on estimating the stiffness properties while poor resultson predicting the strength properties of thermally modified boards.The result shows anoverestimation of modulus of elasticity (MOE) from time-of-flight test compared withthe MOEs gathered from static bending test and resonance frequency test for both thermally modified boards and unmodified ones. The stiffness properties of boards after thermal modification reduced slightly (6.5%) compared with unmodified timbers; while strength properties of thermally modified boards decreased (37.5%) significantlycompared with control group.This study is a part of a bigger study performed at Linneaus University by Joran vanBlokland.

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20

Merli, Francesca. "Static and dynamic elastic moduli of historical brick masonry subjected to freeze-thaw cycles and to different moisture amounts." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.

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Environment conditions and moisture presence in masonry structures may affect durability or even mechanical properties of architectural heritage. Among all the deterioration causes, the degradation of historic masonry by freeze-thaw cycles and different moisture amount are considered to evaluate their influence on elastic properties. Therefore, two experimental campaigns were carried out in the present study. The first one was performed at the Dept. of Geotechincal Engineering at Tongji University, to assess the influence of freeze-thaw cycles on elastic modulus of historic Chinese brick. The static elastic modulus was evaluated from the compressive strength test on masonry specimens subjected to different numbers of freeze-thaw cycles. Moreover, strength decay of the masonry was investigated, also analysing data obtained during ultrasonic test (UPV, non-destructive test). The aim of this step was to obtain the dynamic elastic modulus. Thanks to interpolation of the obtained data it was possible to improve the knowledge of the Elasticity modulus’ reduction of historic masonry subjected to freeze-thaw cycles. The second experimental campaign was performed at DICAM, University of Bologna, on ancient Chinese and Italian bricks, to assess the sensitivity of dynamic elastic modulus to moisture amount. In particular the influence of water presence in the material pores on the UPV measurements. The close relationship between the ultrasonic pulse velocity and the moisture content was investigated on brick cores in dry, 50% saturated and saturated conditions. Practical value and one of the main contribution of the experiments was the investigation of external factor and intrinsic properties of porous materials which directly influence the ultrasonic pulse velocity test.

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21

Mamun, Md Abdullah Al, and Aklima Khanam. "Concurrent Software Testing : A Systematic Review and an Evaluation of Static Analysis Tools." Thesis, Blekinge Tekniska Högskola, Sektionen för datavetenskap och kommunikation, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-4310.

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Verification and validation is one of the most important concerns in the area of software engineering towards more reliable software development. Hence it is important to overcome the challenges of testing concurrent programs. The extensive use of concurrent systems warrants more attention to the concurrent software testing. For testing concurrent software, automatic tools development is getting increased focus. The first part of this study presents a systematic review that aims to explore the state-of-the-art of concurrent software testing. The systematic review reports several issues like concurrent software characteristics, bugs, testing techniques and tools, test case generation techniques and tools, and benchmarks developed for the tools. The second part presents the evaluation of four commercial and open source static analysis tools detecting Java multithreaded bugs. An empirical evaluation of the tools would help the industry as well as the academia to learn more about the effectiveness of the static analysis tools for concurrency bugs.

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22

Ertugrul, Ozgur Lutfi. "Influence Of Deformable Geofoam Bufers On The Static And Dynamic Behaviors Of Cantilever Retaining Walls." Phd thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613734/index.pdf.

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Static and dynamic interaction mechanism of the retained soil-compressible geofoam buffer and yielding retaining structures requires further investigation. The present study, initiated on this motive, discusses the results of 1-g physical model tests and numerical analyses of cantilever retaining walls with and without deformable geofoam buffers between the wall and cohesionless granular backfill. 0.7m high walls with various wall thicknesses were utilized in the physical modeling. Dynamic tests were carried out by using a laminar container placed on a uni-axial shaking table. Influence of buffer thickness, geofoam type and wall flexibility as well as base excitation characteristics on the lateral earth pressures and flexural wall deflections were under concern. Outcomes of the analyses performed with FLAC-2D (v6.0) finite difference code were validated against the results of the physical model tests. It was observed that the arching effect induced in the retained soil by the lateral compression of the lower half of the geofoam buffer has a positive effect, as this zone is able to absorb a portion of the total unbalanced lateral force exerted by the backfill thus causing a reduction in the static and seismic lateral wall pressures. Relative thickness and stiffness of the geofoam buffer appear to be the most dominant factors affecting the reduction in earth thrust. Lateral earth pressure coefficients determined from physical model tests were compared with those calculated using methods available in the literature. Good agreement was observed between the predictions. Graphs were provided to estimate the static and dynamic lateral earth pressure coefficients for various combinations of wall stiffness and buffer characteristics. Analysis of a 6m high prototype cantilever wall subjected to an excitation recorded in August 17, 1999 Kocaeli earthquake by finite difference method exhibited the contribution of geofoam buffers on seismic performance of cantilever earth retaining walls. It was observed that the presence of an EPS geofoam inclusion provides a reduction of the permanent flexural wall deflections as well as total seismic thrust likely to be experienced by the wall during an earthquake.

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23

Nioti, Antonia Eugenia. "Konstruktion av mekanisk anordning för utförande av test- och övningsflyg på en kvadrokopter." Thesis, Högskolan i Gävle, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-22980.

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Testning av flygkontroller på en verklig kvadrokopter är en farlig och utmanande process eftersom kvadrokoptern kan krascha om flygkontrollern inte fungerar eller ifall operatören saknar flygerfarenheter. Den nuvarande lösningen är att montera kvadrokoptern i en mekanisk anordning som möjliggör testning av flygkontroller i säkra miljöer. Problemet med de befintliga testanordningarna är att de inte kan ge realistiska simuleringsförhållanden eftersom de i viss mån påverkar kvadrokopterns rörelse med följden att flygkontroller som utvecklas har begränsad grad av kontroll på kvadrokoptern. Syftet är att utforma en mekanisk anordning som ska ge möjlighet att både testa samt övningsflyga kvadrokoptern utan risk för personliga och materiella skador. Målet är att ta fram ritningar som ska kunna utgöra underlag för framtagning av en testprototyp. En litteraturstudie på befintliga testanordningar genomfördes som användes som underlag tillsammans med kvalitetshuset för att ta fram en kravspecifikation. Därefter genererades ett antal koncept som utvärderades med hjälp av beslutsmatris. Det valda konceptet modellerades sedan i CAD-programmet och utifrån den virtuella modellen konstruerades en verklig modell i trä som testades för att verifiera dess funktion. Resultatet är en fjäderbalanserad testanordning med sex frihetsgrader. Det är en konstruktion i aluminium innehållande en mekanisk arm som ger tre translationsfrihetsgrader, ett kulledsfäste som ger tre rotationsfrihetsgrader samt dragfjädrar för att tyngdkraftskompensera systemet. Testning av trä-modellen uppvisar att kvadrakoptern måste framföras i full fart för att styras tillsammans med armen eftersom friktionen mellan testanordningens leder är hög. Under förutsättning att friktionen mellan lederna kan hanteras verkar det att testanordningen uppfyller de ställda teoretiska förutsättningarna för att inte ha någon väsentlig påverkan på kvadrokoptern. Ändå kravs det kvalificerade tester innan något påstående att testanordningen inte påverkar kvadrokopterns rörelse och därmed kan ge realistiska flygsimuleringsförhållanden, ska kunna anges.
Testing of autonomous flight controllers on a real quadrocopter is a dangerous and challenging process because the quadrocopter can crash in case the flight controller does not function properly or in case the operator has no flight experience. The current solution is to mount the quadrocopter on a teststand, which allow the testing of flight controller in safe environments. The problem with the existing teststands is that they cannot provide realistic free flight conditions as they, to some extent, affect quadrocopter’s movement. Consequently, the developed flight controller is partially able to control the quadrocopter. The purpose with this study is to design a mechanical device for use in testing and learning to fly a quadrocopter without the risk of crashing the flying model or harming the people involved. The goal is to provide drawings for developing a test prototype.In order to understand the problem a literature review of previous test devices was carried out. The findings from the literature review were used in combination with Quality Function Deployment technique to create a House of Quality and thus develop a set of engineering specifications. After that, a number of concepts was generated and then evaluated by Pugh’s method. The selected concept was modeled in the CAD-software and based on the virtual model, a real model made of wood was constructed and tested in order to verify the function of the testbed. The final result is a spring-balanced test device with six degrees of freedom. It is a structure consisting of a mechanical arm providing three translational degrees of freedom, a swivel joint with three rotational degrees of freedom and a set of extension springs to achieve gravity balancing. The experimental results from the wooden model shows that the quadrocopter is required to fly at full speed in order for it to operate with the arm due to the high friction between the joints. Under the condition that the friction between the joints can be managed, the test device seems to fulfill the theoretical requirements for simulating free flight condition. Nevertheless, it requires specialized and advanced testing before any assertion that the test device does not affect the dynamics of quadrocopter and thus it can provide completely realistic flight conditions, can be made.

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Noreña, Pablo Cesar Trejo. "Estimativa da eficiência do ensaio SPT através da execução da prova de carga estática sobre o amostrador." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/18/18132/tde-08112012-113424/.

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O ensaio de simples reconhecimento com o SPT é um dos mais utilizados para investigação do subsolo nos EUA e no Brasil. Os dados obtidos com este ensaio dinâmico, tais como o índice de resistência à penetração NSPT, classificação do solo e nível freático são usados por diferentes métodos para estimativa de capacidade de carga de fundações rasas e profundas. Para um mesmo solo, o índice NSPT pode ser diferente se diferentes equipamentos forem usados devido ao fato de que diferentes equipamentos de SPT mostram diferentes níveis de eficiência. Em vista disso, uma alternativa para estimar a eficiência do ensaio SPT é utilizando-se o ensaio de prova de carga estática sobre o amostrador. Este ensaio foi implementado para poder avaliar a eficiência do ensaio SPT. Para este fim, foram executados 13 ensaios dinâmicos e 13 ensaios estáticos no campus experimental do Laboratório de Engenharia Civil da UNESP (Bauru). Para estimar a eficiência do ensaio SPT através do ensaio dinâmico, um sistema de aquisição analógico-digital foi utilizado para obter registros de aceleração e força na seção localizada junto ao amostrador SPT. O ensaio dinâmico foi modificado para utilizar várias energias potenciais nominais do martelo e sistemas de elevação. A determinação da eficiência do ensaio através da execução da prova de carga estática foi obtida com base no princípio de Hamilton. Adicionalmente, realizando-se a comparação entre o comportamento de carregamento dinâmico e estático, pode-se obter a resistência estática do sistema amostrador-solo. Esta resistência é calculada utilizando a base de dados obtidas no campo e a aplicação de vários métodos de estimativa como: Aoki et al.(2007), De Souza (2009) e Odebrecht (2003). Os resultados da estimativa da eficiência através do ensaio de prova de carga estática sobre o amostrador mostraram-se consistentes em relação aos valores obtidos com o ensaio dinâmico. Concluiu-se que a execução do ensaio de prova de carga estática sobre, o amostrador é uma alternativa simples e econômica para obter a eficiência do SPT.
The Standard Penetration Test, SPT, is one of the most used one for subsoil information in the USA and Brazil. The data obtained in this dynamic test, such as the penetration resistance index, NSPT, the soil classification and phreatic level are used by different methods to estimate the shallow and deep foundations load capacity. For the same soil, the index NSPT can be different if different equipments are used, because different SPT equipments show different efficiency levels. Having this in mind, an alternative to estimate the essay efficiency of the SPT test is using the static load test (SLT) to the sampler. This test was implemented in order to evaluate the efficiency of SPT. To do so, 13 dynamic tests and 13 static tests were performed in the experimental campus of the State University of São Paulo at Bauru (Unesp- Bauru-Brazil). To estimate the efficiency of the SPT test through the dynamic test, a data acquisition system was used to register accelerations and forces at the located section close to the sampler SPT. The dynamic test was modified so that it would be possible to use many nominal potential energy of the hammer and elevation systems. The estimation of the efficiency made through the SLT tests was based on Hamilton\'s principle. Furthermore, by comparing the dynamic and static behavior, we can get the soil-sampler interface static resistance. This resistance is calculated by using the field data through various estimation methods such as Aoki\'s (2007), De Souza\'s (2009) and Odebrecht\'s (2003). The estimates of the efficiency obtained through SLT test were found to be consistent with those obtained through the SPT modified tests. We conclude that SLT is a simple and non-expensive alternative to obtain the efficiency of SPT equipment.

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25

Zhang, Ningning. "A micromechanical study of the Standard Penetration Test." Doctoral thesis, Universitat Politècnica de Catalunya, 2020. http://hdl.handle.net/10803/668841.

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This thesis explores the potential of models based on the discrete element method (DEM) to study dynamic probing of granular materials, considering realistic particle-scale properties. The virtual calibration chamber technique, based on the discrete element method, is applied to study the standard penetration test (SPT). A macro-element approach is used to represent a rod driven with an impact like those applied to perform SPT. The rod is driven into a chamber filled with a scaled discrete analogue of a quartz sand. The contact properties of the discrete analogue are calibrated simulating two low-pressure triaxial tests. The rod is driven changing input energy and controlling initial density and confinement stress. Energy-based blowcount normalization is shown to be effective. Results obtained are in good quantitative agreement with well-accepted experimentally-based relations between blowcount, density and overburden. A comprehensive energetic balance of the virtual calibration chamber is conducted. Energy balance is applied separately to the driven rod and the chamber system, giving a detailed account of all the different energy terms. The characterization of the evolution and distribution of each energy component is investigated. It appears that the SPT test input energy is mainly dissipated in friction. The energy-based interpretation of SPT dynamic response proposed by Schnaid et al. (2017) is then validated in comparisons between static and dynamic penetration results. Moreover, microscale investigation provides important information on energy dissipation mechanisms. A well-established DEM crushing contact model and a rough Hertzian contact model are combined to incorporate both effects in a single contact model. The efficient user defined contact model (UDCM) technique is used for the contact model implementation. Parametric studies explore the effect of particle roughness on single particle crushing event. The model is then used to recalibrate the contact properties of the quartz sand, being able to use realistic contact properties and then correctly capture both load-unload behaviour and particle size distribution evolution. The calibration chamber results are exploited to investigate the relation between static and dynamic penetration test. This is done first for unbreakable materials and later for crushable and rough-crushable ones. It is shown that the tip resistance measured under impact dynamic penetration conditions is very close to that under constant velocity conditions, hence supporting recent proposals to relate CPT and SPT results. It is also shown that penetration resistance reduces if particles are allowed to break, particularly when roughness is also considered.
Esta tesis explora el potencial de los modelos basados en el método de elementos discretos (DEM) para estudiar el sondeo dinámico de materiales granulares, considerando propiedades realistas a escala de partículas. La técnica de cámara de calibración virtual, basada en el método de elemento discreto, se aplica para estudiar la prueba de penetración estándar (SPT). Se utiliza un enfoque de macroelemento para representar una barra impulsada con un impacto como los aplicados para realizar SPT. La varilla se introduce en una cámara llena de un análogo discreto escalado de arena de cuarzo. Las propiedades de contacto del análogo discreto se calibran simulando dos pruebas triaxiales de baja presión. La varilla se acciona cambiando la energía de entrada y controlando la densidad inicial y el estrés de confinamiento. La normalización del recuento de golpes basado en energía se muestra efectiva. Los resultados obtenidos están en buen acuerdo cuantitativo con relaciones basadas en experimentos bien aceptadas entre recuento de golpes, densidad y sobrecarga. Se realiza un balance energético integral de la cámara de calibración virtual. El balance de energía se aplica por separado a la varilla impulsada y al sistema de cámara, dando una descripción detallada de todos los diferentes términos de energía. Se investiga la caracterización de la evolución y distribución de cada componente energético. Parece que la energía de entrada de prueba SPT se disipa principalmente en fricción. La interpretación basada en la energía de la respuesta dinámica SPT propuesta por Schnaid et al. (2017) luego se valida en comparaciones entre los resultados de penetración estática y dinámica. Además, la investigación en microescala proporciona información importante sobre los mecanismos de disipación de energía. Un modelo de contacto de trituración DEM bien establecido y un modelo de contacto hertziano aproximado se combinan para incorporar ambos efectos en un modelo de contacto único. La técnica eficiente de modelo de contacto definido por el usuario (UDCM) se utiliza para la implementación del modelo de contacto. Los estudios paramétricos exploran el efecto de la rugosidad de las partículas en el evento de trituración de partículas individuales. El modelo se usa para recalibrar las propiedades de contacto de la arena de cuarzo, pudiendo usar propiedades de contacto realistas y luego capturar correctamente el comportamiento de carga y descarga y la evolución de la distribución del tamaño de partícula. Los resultados de la cámara de calibración se explotan para investigar la relación entre la prueba de penetración estática y dinámica. Esto se hace primero para materiales irrompibles y luego para materiales triturables y desmenuzables. Se muestra que la resistencia de la punta medida en condiciones de penetración dinámica de impacto es muy cercana a la de condiciones de velocidad constante, por lo tanto, respalda propuestas recientes para relacionar los resultados de CPT y SPT. También se muestra que la resistencia a la penetración se reduce si se permite que las partículas se rompan, particularmente cuando también se considera la aspereza.

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26

Heim, Eugene Henry DeWendt. "Development of Methods for Improved Data Integrity and Efficient Testing of Wind Tunnel Models for Dynamic Test Conditions in Unsteady and Nonlinear Flight Regimes." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/31050.

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Todayâ s high performance aircraft are operating in expanded flight envelopes, often maneuvering at high angular rates at high angles-of-attack, even above maximum lift. Current aerodynamic models are inadequate in predicting flight characteristics in the expanded envelope, such as rapid aircraft departures and other unusual motions. Unsteady flows of aircraft are of real concern. The ability to accurately measure aerodynamic loads directly impacts the ability to accurately model and predict flight. Current wind tunnel testing techniques do not adequately address the data fidelity of a test point under the influence of fluctuating loads and moments. Additionally, forced oscillation test techniques, one of the primary tools used to develop dynamic models, do not currently provide estimates of the uncertainty of the results during an oscillation cycle. Further, in testing models across a range of flight conditions, there are frequently parts of the envelope which are well behaved and require few data points to arrive at a sound answer, and other parts of the envelope where the responses are much more active and require a large sample of data to arrive at an answer with statistical significance. Currently, test methods do not factor changes of flow physics into data acquisition schemes, so in many cases data are obtained over more iterations than required, or insufficient data may be obtained to determine a valid estimate. Methods of providing a measure of data integrity for static and forced oscillation test techniques are presented with examples. A method for optimizing required forced oscillation cycles based on decay of uncertainty gradients and balance tolerances is also presented.
Master of Science

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27

Vorobyev, Alexey. "Static and time-dependent mechanical behaviour of preserved archaeological wood : Case studies of the seventeenth century warship Vasa." Doctoral thesis, Uppsala universitet, Tillämpad mekanik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-314266.

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Wooden objects have been widely used in the history of humanity and play an important role in our cultural heritage. The preservation of such objects is of great importance and can be a challenging task. This thesis investigates the static and time-dependent mechanical behaviour of archaeological oak wood from the Vasa warship. Characterisation of mechanical properties is necessary for the formulation of a numerical model to design an improved support structure. The ship was impregnated with polyethylene glycol (PEG) for dimensional stabilisation. All elastic engineering constants of the Vasa oak have been identified and compared with those of recent oak by means of the static and dynamic testing. The experiments were done on samples with cubic geometry, which allowed obtaining all elastic constants from a single sample. The usage of cubic samples with orthotropic mechanical properties during compressive experiments was validated with finite-element simulations. The Young's moduli of the Vasa oak in all orthotropic directions were smaller than those for the recent oak. The shear moduli of Vasa oak was determined and verified with the resonant ultrasound spectroscopy. The time-dependent mechanical behaviour of the Vasa oak has been studied. Creep studies were performed in uniaxial compression on the cubic samples in all orthotropic directions. The samples loaded in the longitudinal direction were subjected to different stress levels. A stress level below 15% of the yield stress in the longitudinal direction did not result in non-linear creep with increasing creep rates within the time frame of the tests. The results of the studies in radial and tangential directions showed that creep was dominated by the effect of annual fluctuations in relative humidity and temperature. The weight changes based on annual fluctuations of relative humidity were measured for Vasa oak and recent oak. The Vasa oak showed higher variations due to an increased hygroscopicity which is the result of the impregnation with PEG. In conceiving a full-scale finite-element model of Vasa ship, not only the stress-strain relations of the material but also those of the structural joints are needed. Since the in-situ measurement of joints is not an option, a replica of a section of the ship hull was built and tested mechanically. The load-induced displacements were measured using 3D laser scanning which proved to have advantages to conventional point displacement measurements. The mechanical characteristics of the Vasa oak and joint information presented in this work can be used as input for a finite-element model of the Vasa ship for simulation of static and time-dependent behaviour on a larger scale.
Stötta Vasa

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28

Kevan, Luke Ian. "Full-Scale Testing of Blast-Induced Liquefaction Downdrag on Driven Piles in Sand." BYU ScholarsArchive, 2017. https://scholarsarchive.byu.edu/etd/6966.

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Deep foundations such as driven piles are often used to bypass liquefiable layers of soil and bear on more competent strata. When liquefaction occurs, the skin friction around the deep foundation goes to zero in the liquefiable layer. As the pore pressures dissipate, the soil settles. As the soil settles, negative skin friction develops owing to the downward movement of the soil surrounding the pile. To investigate the magnitude of the skin friction along the shaft three driven piles, an H-pile, a closed end pipe pile, and a concrete square pile, were instrumented and used to measure soil induced load at a site near Turrell, Arkansas following blast-induced liquefaction. Measurements were made of the load in the pile, the settlement of the ground and the settlement of piles in each case. Estimates of side friction and end-bearing resistance were obtained from Pile Driving Analyzer (PDA) measurements during driving and embedded O-cell type testing. The H-pile was driven to a depth of 94 feet, the pipe pile 74 feet, and the concrete square pile 72 feet below the ground surface to investigate the influence of pile depth in response to liquefaction. All three piles penetrated the liquefied layer and tipped out in denser sand. The soil surrounding the piles settled 2.5 inches for the H-pile, 2.8 inches for the pipe pile and 3.3 inches for the concrete square pile. The piles themselves settled 0.28 inches for the H-pile, 0.32 inches for the pipe pile, and 0.28 inches for the concrete square pile. During reconsolidation, the skin friction of the liquefied layer was 43% for the H-pile, 41% for the pipe pile, and 49% for the concrete square pile. Due to the magnitude of load felt in the piles from these tests the assumption of 50% skin friction developing in the liquefied zone is reasonable. Reduced side friction in the liquefied zone led to full mobilization of skin friction in the non-liquefied soil, and partial mobilization of end bearing capacity. The neutral plane, defined as the depth where the settlement of the soil equals the settlement of the pile, was outside of the liquefied zone in each scenario. The neutral plane method that uses mobilized end bearing measured during blasting to calculate settlement of the pile post liquefaction proved to be accurate for these three piles.

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Nylén, Christoffer. "Improving MCDC adequate test sets for safety critical software to be RORG adequate." Thesis, Linköpings universitet, Programvara och system, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-121729.

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A number of logical code coverage criteria have been used throughout the years in the testing of safety-critical software. Kaminski, et al. proposed Relational Operator Replacement Global (RORG), a method to bring benefits from ROR mutation to Modified Condition / Decision Coverage (MCDC), which is widely used in the avionics industry. However, there is a lack of studies in the industry to support this method. In this thesis, we report on the results of applying RORG to avionic code, augmenting an MCDC adequate test set to satisfy RORG, evaluating its ability to find real faults in industrial software. Conclusions drawn from this thesis are: (1) Faults in relational operators in avionic code are rare, no faults were found in this study. (2) 24% of the relational operators in our study would require additional software requirements to be verified for RORG coverage. (3) 37% of the relational operators in our study were infeasible to test due to program semantics. (4) 84% of the tests added covered enumeration comparisons.

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30

Dworak, Jennifer Lynn. "Modeling defective part level due to static and dynamic defects based upon site observation and excitation balance." Diss., Texas A&M University, 2004. http://hdl.handle.net/1969.1/323.

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Manufacture testing of digital integrated circuits is essential for high quality. However, exhaustive testing is impractical, and only a small subset of all possible test patterns (or test pattern pairs) may be applied. Thus, it is crucial to choose a subset that detects a high percentage of the defective parts and produces a low defective part level. Historically, test pattern generation has often been seen as a deterministic endeavor. Test sets are generated to deterministically ensure that a large percentage of the targeted faults are detected. However, many real defects do not behave like these faults, and a test set that detects them all may still miss many defects. Unfortunately, modeling all possible defects as faults is impractical. Thus, it is important to fortuitously detect unmodeled defects using high quality test sets. To maximize fortuitous detection, we do not assume a high correlation between faults and actual defects. Instead, we look at the common requirements for all defect detection. We deterministically maximize the observations of the leastobserved sites while randomly exciting the defects that may be present. The resulting decrease in defective part level is estimated using the MPGD model. This dissertation describes the MPGD defective part level model and shows how it can be used to predict defective part levels resulting from static defect detection. Unlike many other predictors, its predictions are a function of site observations, not fault coverage, and thus it is generally more accurate at high fault coverages. Furthermore, its components model the physical realities of site observation and defect excitation, and thus it can be used to give insight into better test generation strategies. Next, we investigate the effect of additional constraints on the fortuitous detection of defects-specifically, as we focus on detecting dynamic defects instead of static ones. We show that the quality of the randomness of excitation becomes increasingly important as defect complexity increases. We introduce a new metric, called excitation balance, to estimate the quality of the excitation, and we show how excitation balance relates to the constant τ in the MPGD model.

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Neves, Luis Fernando de Seixas. "Metodologia para a determinação da eficiência do ensaio SPT através de prova de carga estática sobre o amostrador padrão." Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/18/18132/tde-02032016-142441/.

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O ensaio de simples reconhecimento de solos (SPT) é a ferramenta de investigação de solos mais utilizada no mundo. Devido ao grande número de parâmetros que influenciam os seus resultados, a medida de sua eficiência passa a ser indispensável à transposição de experiências entre as práticas desenvolvidas em diferentes locais. Infelizmente, a medida da eficiência através da instrumentação do impacto do martelo é economicamente inviável para a maioria das empresas de sondagem no Brasil. Este trabalho apresenta uma metodologia para a determinação da eficiência do SPT baseada no princípio de Hamilton e na realização de prova de carga estática sobre o amostrador, que pode ser uma alternativa para sanar esta situação.
The standard penetration test (SPT) is the most used soil investigation tool in the world. Due to the great number of variables that influences its results, the measurement of the efficiency becomes imperative to the transposition of experiences between developed practices in different places. Unfortunately, the measurement of the efficiency through the instrumentation of the hammer impact is economically inpracticable to most of the soil investigation firms in Brazil. This work presents a methodology to determinate the SPT efficiency based on the Hamilton\'s principle and on the execution of static load test over the sampler, what seems to be a good alternative to end this situation.

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32

Hameury, Ollivier. "Quelques aspects du comportement des sables avec et sans rotation des axes principaux : des petites aux grandes déformations." Châtenay-Malabry, Ecole centrale de Paris, 1995. http://www.theses.fr/1995ECAP0397.

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Ce travail, accompli au sein d'un laboratoire français et d'un laboratoire italien, est une contribution à l'étude du comportement des sables, depuis les faibles déformations jusqu'a la rupture. Une campagne d'essais, entreprise en petites et moyennes déformations sur plusieurs dispositifs expérimentaux, a montré la cohérence des différentes mesures, aussi bien statiques que dynamiques. Elle a de plus permis de quantifier la précision relative de chaque appareillage et de mettre en évidence le comportement mécanique très particulier des sables carbonates. Ces matériaux, en dépit d'une forte compressibilité, ont témoigné d'une rigidité initiale élevée, mais fortement dépendante de la pression moyenne. Leurs modules en petites déformations se sont en outre révélés extrêmement sensibles à une surconsolidation mécanique, du fait d'une réorganisation de leurs particules favorisée par des effets d'attrition. La déformation augmentant, deux seuils sont apparus, qui délimitent d'une part la zone élastique et d'autre part la zone de comportement stable. L'évolution des propriétés rhéologiques dans chaque domaine a été analysée à partir de quelques paramètres d'influence, puis retranscrite dans des modèles simples. La dernière partie expérimentale de ce mémoire a été consacrée à l'étude de sollicitations cycliques non drainées incluant des rotations d'axes principaux, à l'aide d'un appareil de cylindre creux. Au cours de ces essais, réalisés en torsion à déviateur axial constant, nous avons observé une orientation progressive de la déformation principale majeure vers la verticale, ainsi que la remontée d'une surface limite différente de la surface de rupture obtenue en conditions drainées, ce que nous avons interprété par une généralisation du concept d'état caractéristique. Nous avons enfin examiné les prédictions d'un modèle incrémental de type interpolation sur quelques chemins de sollicitation complexes

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33

Chebaro, Omar. "Classification de menaces d’erreurs par analyse statique, simplification syntaxique et test structurel de programmes." Thesis, Besançon, 2011. http://www.theses.fr/2011BESA2021/document.

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La validation des logiciels est une partie cruciale dans le cycle de leur développement. Deux techniques de vérification et de validation se sont démarquées au cours de ces dernières années : l’analyse statique et l’analyse dynamique. Les points forts et faibles des deux techniques sont complémentaires. Nous présentons dans cette thèse une combinaison originale de ces deux techniques. Dans cette combinaison, l’analyse statique signale les instructions risquant de provoquer des erreurs à l’exécution, par des alarmes dont certaines peuvent être de fausses alarmes, puis l’analyse dynamique (génération de tests) est utilisée pour confirmer ou rejeter ces alarmes. L’objectif de cette thèse est de rendre la recherche d’erreurs automatique, plus précise, et plus efficace en temps. Appliquée à des programmes de grande taille, la génération de tests, peut manquer de temps ou d’espace mémoire avant de confirmer certaines alarmes comme de vraies erreurs ou conclure qu’aucun chemin d’exécution ne peut atteindre l’état d’erreur de certaines alarmes et donc rejeter ces alarmes. Pour surmonter ce problème, nous proposons de réduire la taille du code source par le slicing avant de lancer la génération de tests. Le slicing transforme un programme en un autre programme plus simple, appelé slice, qui est équivalent au programme initial par rapport à certains critères. Quatre utilisations du slicing sont étudiées. La première utilisation est nommée all. Elle consiste à appliquer le slicing une seule fois, le critère de simplification étant l’ensemble de toutes les alarmes du programme qui ont été détectées par l’analyse statique. L’inconvénient de cette utilisation est que la génération de tests peut manquer de temps ou d’espace et les alarmes les plus faciles à classer sont pénalisées par l’analyse d’autres alarmes plus complexes. Dans la deuxième utilisation, nommée each, le slicing est effectué séparément par rapport à chaque alarme. Cependant, la génération de tests est exécutée pour chaque programme et il y a un risque de redondance d’analyse si des alarmes sont incluses dans d’autres slices. Pour pallier ces inconvénients, nous avons étudié les dépendances entre les alarmes et nous avons introduit deux utilisations avancées du slicing, nommées min et smart, qui exploitent ces dépendances. Dans l’utilisation min, le slicing est effectué par rapport à un ensemble minimal de sous-ensembles d’alarmes. Ces sous-ensembles sont choisis en fonction de dépendances entre les alarmes et l’union de ces sous-ensembles couvre l’ensemble de toutes les alarmes. Avec cette utilisation, on a moins de slices qu’avec each, et des slices plus simples qu’avec all. Cependant, l’analyse dynamique de certaines slices peut manquer de temps ou d’espace avant de classer certaines alarmes, tandis que l’analyse dynamique d’une slice éventuellement plus simple permettrait de les classer. L’utilisation smart consiste à appliquer l’utilisation précédente itérativement en réduisant la taille des sous-ensembles quand c’est nécessaire. Lorsqu’une alarme ne peut pas être classée par l’analyse dynamique d’une slice, des slices plus simples sont calculées. Nous prouvons la correction de la méthode proposée. Ces travaux sont implantés dans sante, notre outil qui relie l’outil de génération de tests PathCrawler et la plate-forme d’analyse statique Frama-C. Des expérimentations ont montré, d’une part, que notre combinaison est plus performante que chaque technique utilisée indépendamment et, d’autre part, que la vérification devient plus rapide avec l’utilisation du slicing. De plus, la simplification du programme par le slicing rend les erreurs détectées et les alarmes restantes plus faciles à analyser
Software validation remains a crucial part in software development process. Two major techniques have improved in recent years, dynamic and static analysis. They have complementary strengths and weaknesses. We present in this thesis a new original combination of these methods to make the research of runtime errors more accurate, automatic and reduce the number of false alarms. We prove as well the correction of the method. In this combination, static analysis reports alarms of runtime errors some of which may be false alarms, and test generation is used to confirm or reject these alarms. When applied on large programs, test generation may lack time or space before confirming out certain alarms as real bugs or finding that some alarms are unreachable. To overcome this problem, we propose to reduce the source code by program slicing before running test generation. Program slicing transforms a program into another simpler program, which is equivalent to the original program with respect to certain criterion. Four usages of program slicing were studied. The first usage is called all. It applies the slicing only once, the simplification criterion is the set of all alarms in the program. The disadvantage of this usage is that test generation may lack time or space and alarms that are easier to classify are penalized by the analysis of other more complex alarms. In the second usage, called each, program slicing is performed with respect to each alarm separately. However, test generation is executed for each sliced program and there is a risk of redundancy if some alarms are included in many slices. To overcome these drawbacks, we studied dependencies between alarms on which we base to introduce two advanced usages of program slicing : min and smart. In the min usage, the slicing is performed with respect to subsets of alarms. These subsets are selected based on dependencies between alarms and the union of these subsets cover the whole set of alarms. With this usage, we analyze less slices than with each, and simpler slices than with all. However, the dynamic analysis of some slices may lack time or space before classifying some alarms, while the dynamic analysis of a simpler slice could possibly classify some. Usage smart applies previous usage iteratively by reducing the size of the subsets when necessary. When an alarm cannot be classified by the dynamic analysis of a slice, simpler slices are calculated. These works are implemented in sante, our tool that combines the test generation tool PathCrawler and the platform of static analysis Frama-C. Experiments have shown, firstly, that our combination is more effective than each technique used separately and, secondly, that the verification is faster after reducing the code with program slicing. Simplifying the program by program slicing also makes the detected errors and the remaining alarms easier to analyze

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34

Gong, Ting. "Tensile behavior of high-performance cement-based composites with hybrid reinforcement subjected to quasi-static and impact loading." Technische Universität Dresden, 2020. https://tud.qucosa.de/id/qucosa%3A73914.

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Hochduktile Betone (Engl.: Strain-Hardening Cement-based Composites – SHCC) und Textilbetone (engl.: Textile Reinforced Concrete – TRC) sind zwei neuartige Faserbetone, die ein duktiles und dehnungsverfestigendes Zugverhalten aufweisen. SHCC bestehen aus feinkörnigen Zementmatrizen und kurzen Hochleistungspolymerfasern, während TRC eine Kombination aus feinkörnigen Zementmatrizen und kontinuierlichen zwei- oder dreidimensionalen Textilschichten darstellt. Letztere bestehen aus Multifilamentgarnen aus Kohlenstoff, alkalibeständigem Glas oder Polymerfasern. Die hohe elastische Verformbarkeit beider Verbundwerkstoffe bis zum Erreichen der Zugfestigkeit entsteht aus der sukzessiven Bildung multipler feiner Risse. Neben der hervorragenden Risskontrolle und Duktilität weisen diese Verbundwerkstoffe ein hohes Energieabsorptionsvermögen auf, was in Bezug auf kurzzeitdynamische Belastungen eine durchaus erstrebenswerte Eigenschaft darstellt. Obwohl SHCC eine höhere Dehnungskapazität als herkömmliche TRC zeigen, weisen die Textilbetone eine erheblich höhere Zugfestigkeit auf. Darüber hinaus besitzen die textilbewehrten Betone deutlich niedrigere Einflüsse von Anwendungstechnologie und Maßstab auf das Zugverhalten, d. h. eine bessere Robustheit. Daher stellt die Kombination dieser beiden Bewehrungskonzepte einen vielversprechenden Ansatz dar. Während die Kurzfasern für eine bessere Risskontrolle und Erstrissfestigkeit sorgen, sichern die Textilgelege eine hohe Zugfestigkeit sowie Steifigkeit im gerissenen Zustand und eine gleichmäßige Verteilung der Kräfte in der Verstärkungsschicht bzw. im Bauteil. Dieser synergetische Effekt kann jedoch nur durch eine zielgerichtete Materialentwicklung erreicht werden, die eine grundlegende Materialcharakterisierung unter verschiedenen Belastungsszenarien erfordert. Im Rahmen des DFG-finanzierten Graduiertenkollegs GRK 2250 „Impaktsicherheit von Baukonstruktionen durch mineralisch gebundene Komposite“ werden duktile und Impakt resistente Komposite entwickelt, charakterisiert und erprobt, die als dünne Verstärkungsschichten auf bestehende Konstruktionen bzw. Bauelemente aufgetragen werden und dadurch deren Widerstandsfähigkeit und Resilienz gegen extreme kurzzeitdynamische Beanspruchungen signifikant erhöhen. Die in der vorliegenden Arbeit vorgestellten Ergebnisse wurden im Rahmen des A3-Projektes innerhalb des GRK 2250/1 erzielt. Ziel dieser Arbeit war es, die grundlegenden mechanischen Eigenschaften und die Dehnratenabhängigkeit von mineralisch gebundenen Kompositen mit hybrider Faserbewehrung zu erfassen und zu beschreiben. Das Forschungskonzept besteht aus systematischen und parametrischen Untersuchungen der einzelnen Komponenten (Faser, Textil, zementgebundene Matrix), ihres Verbundes und der entsprechenden Verbundwerkstoffe. Hierfür wurden zweckbestimmte Prüfkonfigurationen und dreidimensionale Messverfahren angewandt, die in anderen Projekten des GRK 2250/1 entwickelt wurden. Außer uniaxialen, quasistatischen und dynamischen Zugversuchen wurden quasistatische und dynamische Einzelgarnauszugsversuche durchgeführt. Die wichtigsten untersuchten Materialparameter waren die Art der Kurzfaserbewehrung und der Textilien (Material, geometrische und Oberflächeneigenschaften, Art der Tränkung usw.). Auf Basis der mechanischen Experimente wurde ein analytisches Modell eingesetzt und angepasst, dass das Zugverhalten solcher Komposite in Abhängigkeit von verschiedenen Materialparametern abbilden soll. Zusätzlich zu der detaillierten Beschreibung der Materialeigenschaften, der maßgebenden Mechanismen und synergetischen Effekte bilden die erzielten Ergebnisse eine umfangreiche experimentelle Basis für eine empirische und Modell gestützte Weiterentwicklung und Optimierung dieser Verbundwerkstoffe mit Hinblick auf wirtschaftliche und ökonomische Aspekte.
Strain-hardening cement-based composites (SHCC) and textile-reinforced concrete (TRC) are two novel types of fiber-reinforced cementitious composites that exhibit ductile, strain-hardening tensile behavior. SHCC comprises fine-grained cementitious matrices and short, high-performance polymer fiber, while TRC is a combination of a fine-grained, cementitious matrix and continuous two- or three- dimensional textile layers of multi-filament yarns, usually made of carbon or alkali-resistant glass. Both composites yield high inelastic deformations in a strain-hardening phase due to the successive formation of multiple fine cracks. Such cracking behavior stands for high energy absorption of the composites when exposed to extreme loading, without abrupt loss of load-bearing capacity. In comparative terms, SHCC shows superior strain capacity, while TRC yields considerably higher tensile strength. The addition of short fibers strengthens the matrix by efficiently restraining the micro-cracks’ growth and reducing spallation, while the textile reinforcement ensures a secure confinement of the reinforced concrete element (substrate to be strengthened), as well as a favorable stress distribution. The combination of SHCC and textile reinforcement is expected to deliver high tensile strength and stiffness in the strain-hardening stage along with pronounced multiple cracking. In order to achieve a favorable synergetic effect, a purposeful material design is required based on a clear understanding of the mechanical interactions in the composites. In the framework of the DFG Research Training Group GRK 2250, which aims at enhancing structural impact safety through thin strengthening layers made of high-performance mineral-based composites, this work focuses on developing hybrid fiber-reinforced cementitious materials to be applied on the impact rear side. The development concept builds upon a systematic investigation of various aspects of the mechanical behaviors of SHCC and textile at quasi-static and impact strain rates, including the bond properties of fiber to matrix and textile to matrix. Accordingly, uniaxial quasi-static tension tests were first performed on SHCC, bare textile, and hybrid-reinforced composite specimens. The parameters under investigation were types of short fiber and textile reinforcements, reinforcing the ratio for textile as well as bond properties between textile and the surrounding SHCC. Furthermore, impact tension tests were performed to study the strain rate effect on the synergetic composite response. Finally, single-yarn pull-out tests were carried out under both quasi-static and impact loading rates to supplement the comparative assessment of the hybrid fiber-reinforced composites. These tests yielded shear strength-related parameters for quantifying the bond properties of different materials, which were then used as input of the analytical model developed to describe the mechanics of crack propagation and tension stiffening effect of textile-reinforced composites without short fibers. This model is the first step towards a comprehensive analytical description of the tensile behavior of hybrid fiber-reinforced composites based on the experimental data and input parameters attained through the work at hand.

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Jorlöv, Sofia, and Jessica Hammarström. "Comparison Study of the Two Pediatric ATDs: Hybrid III 6-Year-Old and Q6." Thesis, Högskolan i Halmstad, Biomekanik och biomedicin, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-15393.

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As a new pediatric dummy family, the Q-family, is suggested for the European childsafety regulations (R44) and the updated EuroNCAP, it needed to be tested andcompared to the older pediatric dummy family, Hybrid III, used in testing at Autolivtoday.In this study, tests were performed with the Q6 and the Hybrid III 6-year-old. Bothdummies were subjected to eight sled tests using a EuroNCAP acceleration pulse. The sled represented the interior of a Volvo V70, with integrated booster cushions mounted onto the car body through a rigid fixture. Standard belt were used for all tests, except one where pretensioning was used. Static tests investigated how the chest deflection on Q6 was affected by the shoulder belt geometry. Large difference in belt interaction was observed between the dummies. The beltslipped off the Hybrid III’s shoulder for all tests except one, while the belt on the Qdummy’swas hard to provoke off the shoulder. The overall kinematic behavior, beforethe belt slipped off the Hybrid III’s shoulder, were similar for both dummies. Differences in chest deflection on the Q6, depending on the belt geometry, were observed in both the dynamic and the static tests; a shoulder belt geometry closer to theneck resulted in minor displacement than a mid-shoulder belt geometry. After testing, five different damages were observed on the Q6.
Då en ny familj av barnkrockdockor, Q-familjen, är föreslagen för det europeiskalagkravet som reglerar barnsäkerhet (R44), uppstod ett behov av att testa och jämföradessa mot den äldre familjen av barnkrockdockor som används vid testning på Autoliv idag, Hybrid III. I den här studien utfördes tester på Q6 och Hybrid III 6 år. Båda dockorna utsattes föråtta stycken slädtest i en accelerationspuls enligt EuroNCAP. Släden representerade enVolvo V70 med integrerade barnkuddar som monterats i riggen via en stel fixtur. I alla test utom ett användes standardbälten (i undantagsfallet användes försträckare). Statiska tester gjordes för att undersöka hur Q6 påverkades av olika geometrier på axelbältet. Stora skillnader observerades mellan dockornas bältesinteraktion. Bältet gled av HybridIII:s axel i alla test förutom ett, medan det istället var svårt att provocera av bältet från Q-dockans axel. Innan Hybrid III gled ur bältet var dockornas kinematik liknande. I både statiska och dynamiska tester observerades skillnader i bröstintryckning på Q6, beroende på bältesgeometrin; en geometri där axelbältet var placerat nära nackenresulterade i en mindre intryckning än då axelbältet var placerat mitt på axeln. Efte ravslutad testning upptäcktes fem skador på Q6.

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Musarra, Marcello Duarte. "Análise de comportamento de estaca barrete embutida em rocha." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/3/3145/tde-29042015-162009/.

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Para proporcionar menores prazos e custos, o projeto de ampliação da sede da Petrobras, na cidade de Salvador, estado da Bahia, contemplou estacas barretes de grandes dimensões para grandes capacidades de carga. Porém, para atingir as cargas escolhidas, foi necessário embutir as estacas no topo rochoso. Portanto, foram projetadas estacas barretes embutidas em rocha, escavadas com hidrofresa. Esta pesquisa apresenta o estudo de duas provas de carga estáticas executadas em uma mesma estaca barrete teste embutida em rocha, a fim de proporcionar um melhor entendimento de seu comportamento, assim como os principais fatores que influenciam resistência e deformabilidade. Em março de 2012, foram realizadas duas provas de carga estáticas na mesma estaca barrete teste embutida em rocha. Os ensaios foram executados a partir das metodologias normativas NBR 12131 (2006) e NBR 6122 (2010), com carregamentos lento e rápido, respectivamente e subsequentemente. No primeiro ensaio (lento), aplicou-se a carga máxima de 12 MN, enquanto que no segundo (rápido), aplicou-se a carga máxima de 14 MN. Os dados obtidos nos ensaios, de acordo com a bibliografia utilizada, são pioneiros no Brasil, por se tratar da primeira estaca barrete embutida em rocha com utilização de hidrofresa, submetida à prova de carga de desempenho. A estaca foi instrumentada em profundidade, o que propiciou a avaliação da distribuição de carga nas camadas atravessadas. Foram realizadas comparações entre resultados obtidos da instrumentação e do topo, por meio do repique elástico. Além da avaliação e interpretação dos dados obtidos nos ensaios de provas de carga estáticas, esta pesquisa apresenta previsões de comportamento, com diferentes conceitos, para estacas embutidas em rocha, sem reação de ponta, com intuito de comparar seus resultados com os obtidos nos ensaios. Em conjunto com as previsões, foram apresentados métodos para estimativa de adesão lateral na interface da estaca com o maciço rochoso.
To use high loads on foundations of the Petobras Headquarters, the designers chose the barrette pile with great dimensions and a few units compared with others types, to shorten the deadline and optimize costs. However, to reach these assumptions, it was necessary make the piles deeper than the soil strata, and, therefore, made a rock socket design. This research presents two static load tests study and analysis in the same barrette test pile, to forecast behavior and find resistance and strain influences. In March, 2012, two static load tests were made in the same barrette test pile located in Salvador Bahia, in Petrobras headquarters. The first essay was made according to a slow maintained test with 12 MN maximum compressive loads. The second essay was made immediately after, according to a quick load test and 14 MN maximum compressive loads. The data obtained from both tests, far as is known, were the first results on rock socket barrette pile in Brazil, using hydromill for the excavations in rock. The pile had depth instrumentation with expansible strain gages and an expanded polystyrene block below the cage, to make the tip useless. Beyond the data assessment and interpretation from static load tests, this research presents forecasting methods to only shear resistance rock socket piles, with the aim of comparison. Lastly but not least, side resistance empirical methods between pile and rock interface were presented.

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Serediuk, Vadym. "Návrh průkazných statických pevnostních zkoušek letounu v kategorii UL." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-443247.

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The diploma thesis involves the design of certification static strength tests for the newly developed aircraft of the TL-Ultralight company. At the beginning of the work, the theory of aircraft testing is generally discussed with emphasis on static strength tests. Furthermore, an analysis of the requirements of the Czech regulation UL 2 and the German LTF-UL, which represent the certification basis for this aircraft, is performed. The requirements of regulations on the construction of the aircraft (or its individual parts) and the requirements for strength tests are discussed in detail. Based on the regulation and the provided calculation protocols, individual test cases and test plans of the wing, tail surfaces, engine bed, and chassis are calculated and prepared. In the end, the calculation of the rocker system and the basic design of jigs are performed.

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Baldassarre, Alessandro. "FEM and experimental analysis of a wind turbine blade." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/8533/.

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This paperwork compares the a numerical validation of the finite element model (FEM) with respect the experimental tests of a new generation wind turbine blade designed by TPI Composites Inc. called BSDS (Blade System Design Study). The research is focused on the analysis by finite element (FE) of the BSDS blade and its comparison with respect the experimental data from static and dynamic investigations. The goal of the research is to create a general procedure which is based on a finite element model and will be used to create an accurate digital copy for any kind of blade. The blade prototype was created in SolidWorks and the blade of Sandia National Laboratories Blade System Design Study was accurately reproduced. At a later stage the SolidWorks model was imported in Ansys Mechanical APDL where the shell geometry was created and modal, static and fatigue analysis were carried out. The outcomes of the FEM analysis were compared with the real test on the BSDS blade at Clarkson University laboratory carried out by a new procedures called Blade Test Facility that includes different methods for both the static and dynamic test of the wind turbine blade. The outcomes from the FEM analysis reproduce the real behavior of the blade subjected to static loads in a very satisfying way. A most detailed study about the material properties could improve the accuracy of the analysis.

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Langone, Marcelo Júlio. "Método UFRGS de previsão de capacidade de carga em estacas : análise de provas de carga estáticas instrumentadas." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/79814.

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Recentemente foi desenvolvido na Universidade Federal do Rio Grande do Sul um método racional para previsão de capacidade de carga em fundações profundas. Denominado de método UFRGS, este procedimento considera conceitos de energias envolvidos durante o ensaio SPT. No presente trabalho, realizou-se estudo da precisão das estimativas fornecidas pela aplicação do método com intuito de compreender, averiguar, ajustar e validar seu uso na prática de engenharia. Para tal, foi gerado um banco de dados de provas de carga estáticas instrumentadas com base na bibliografia nacional e internacional, sendo este constituído de 25 casos em estacas metálicas, 42 em escavadas, 12 do tipo hélice contínua e 10 em prémoldadas. Considerando a resistência mobilizada por atrito lateral, ponta, resistência total e curvas de mobilização, foram gerados gráficos expressando os resultados obtidos pelo método e os resultados medidos nas provas de carga. Adicionalmente, apresenta-se uma comparação com resultados fornecidos por métodos consagrados de previsão de comportamento em estacas: os métodos de Aoki-Velloso, Décourt & Quaresma e interpretação teórica. De maneira geral, o método UFRGS apresentou subestimativas e baixa dispersão para o atrito lateral e uma superestimativa acompanhada de maior dispersão para a ponta das estacas. Da análise dos resultados, verifica-se que o método captura os mecanismos de mobilização de resistência desenvolvidos nas estacas, e reproduz resultados globais compatíveis com os métodos empregados na prática de engenharia. Além disso, apresenta destacada potencialidade haja vista à facilidade de melhoria dos resultados, que através da calibração da energia transferida pelo ensaio SPT, possibilita aplicação e compartilhamento entre diferentes práticas internacionais. Por fim, no âmbito de projeto, destaca-se que dentre todos os métodos empregados, o método estudado forneceu menor dispersão de atrito lateral. Em projetos que envolvem cálculos de risco e probabilidade de ruína, chama-se atenção de que melhorias discretas nos valores de dispersões geram ganho significativo na diminuição dos riscos.
Recently, a rational method for predicting the pile bearing capacity was developed at Federal University of Rio Grande do Sul in Brazil: the so called method UFRGS which considers the concepts of soil dynamics and principles of energy conservation in the interpretation of SPT test results. The present work analyses the accuracy of predicted bearing capacity values with the aim of understanding, verifying, and validating its application in engineering practice. Thus a database of static and instrumented load tests was built from national and international case studies; the data is composed by 25 load tests executed on steel piles, 42 on drilled piles, 12 on continuous flight auger piles and 10 on precast piles. The mobilized contributions of skin friction, tip resistance, and load mobilization curves of each pile were evaluated and compared to actual predictions using the results from UFRGS method. Furthermore, a series of charts were prepared showing comparisons between results of the UFRGS method and those obtained from other predictive methods of pile bearing capacity adopted in the Brazilian engineering practice: Aoki-Velloso and Décourt & Quaresma, as well as a method based on theoretical interpretation of pile response. In general, the UFRGS method underestimated the results for skin friction while slightly overestimate tip resistance and the scatter of predictions is generally lower than other methods. From these analyses, it was possible to conclude that the method captures the mobilization mechanisms developed around piles, and gives predictions which are in the same range as those produced by other methods adopted in Brazil. The UFRGS method has marked potential for being used in design practice given the fact that predictions can be improved by calibrating the SPT energy, which would allow to refine the predictions according to different practices of used worldwide. Finally it is important to stress that the UFRGS method showed the littlest scatter for skin friction assessment which may provide to be significant in risk analysis type of approach.

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Vianna, Ana Paula Fontana. "Análise de provas de carga estática em estacas pré-moldadas cravadas na cidade de Curitiba e região metropolitana." Universidade de São Paulo, 2000. http://www.teses.usp.br/teses/disponiveis/18/18132/tde-18102006-101542/.

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Nesta dissertação são analisadas 34 provas de carga estática realizadas em estacas pré-moldadas de concreto, cravadas em diferentes locais da cidade de Curitiba e região metropolitana, sendo a maioria delas na Formação Guabirotuba. Três métodos de previsão da capacidade foram analisados: Aoki Velloso (1975), Décourt Quaresma (1978) e Amaral (1982, 1999). Para cada método foram propostos fatores de correção global e/ou parcial que tornam o valor da capacidade de carga mais próximo do valor da carga última obtida pelo critério de Van der Veen (1953). Com base em quatro provas de carga conduzidas até a ruptura, estudou-se a aplicabilidade do método de Van der Veen (1953) e determinou-se um critério para avaliar a extrapolação da curva carga x recalque em ensaios encerrados sem atingir a ruptura. Finalmente fez-se uma análise dos recalques comparando-se os valores medidos com os calculados, para três níveis de carregamento, além da comparação das curvas carga x recalque ajustadas com as experimentais.
This thesis presents the analysis of 34 static loading tests in concrete drive pile, located at different places of the Curitiba city and metropolitan area, in Guabirotuba Formation. Three methods of the bearing capacity prediction were assessed: Aoki Velloso (1975), Décourt Quaresma (1978) and Amaral (1982, 1999). For each method is proposed global correction factors and/or partial that turned the bearing capacity value close to the ultimate load obtained for the Van der Veen criteria (1953). Based on four static loading test carried out to failure, the applicability of the Van der Veen criteria was assessed and was determined a rule to evaluate the extrapolation of the load - settlement curve in tests stopped before of the failure. Finally, it was made an analysis of the settlements, where it was compared the observed values and the predicted values, for three loading level, and also a comparison between the experimental load-settlement curve and the predicted load-settlement curve.

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Benvenutti, Márcio. "Cravação de tubulões a céu aberto para melhoria da capacidade de carga em solos colapsíveis." Universidade de São Paulo, 2001. http://www.teses.usp.br/teses/disponiveis/18/18132/tde-26022016-142246/.

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Os tubulões a céu aberto são amplamente utilizados como elementos estruturais de fundação de edifícios residenciais nas cidades pequenas e médias do Brasil. Relatam-se as etapas de um projeto de fundações por tubulões desenvolvido em uma área previamente ocupada por construções residenciais antigas. Após cuidadosa demolição e limpeza, deparou-se com o desafio de executar as fundações sem o perigo de danificar as construções adjacentes (tubulões à céu aberto de divisa nos dois lados e no fundo). No projeto, utilizaram-se procedimentos usuais e alguns específicos que refletem a prática corrente nos últimos 10 anos, na região de Campinas, com resultados extremamente satisfatórios. Nos solos porosos e colapsíveis, presentes em várias regiões brasileiras, as fundações não raramente têm apresentado comportamento inadequado, quando o solo é inundado. Com a significativa elevação do seu teor de umidade, esses solos exibem o recalque de colapso, caracterizando-se como colapsíveis. Como já se tem a comprovação da eficiência da compactação do solo para viabilizar o emprego de fundações rasas, por sapatas, em solos colapsíveis (CINTRA, 1998), resolveu-se estudar os possíveis benefícios da criação de tubulões a céu aberto. No campo experimental de Fundações da USP/São Carlos, foram executadas dois tubulões a céu aberto com fuste de diâmetro de 0,50 m e base apoiada à cota - 6,00 m, com diâmetro de 1,50 m e altura de 0,90 m. O primeiro tubulão a céu aberto foi ensaiado na condição não-inundada do solo, na cota inicial de apoio da base e sucessivamente, com a cravação de 0,15 m, 0,30 m e 0,45 m, o que corresponde a 10%, 20% e 30% do diâmetro da base, respectivamente. Observou-se que a cravação majorou a capacidade de carga em 42%, 85% e 12%, respectivamente. O segundo tubulão a céu aberto foi ensaiado com o solo pré-inundado, para quantificar o efeito da colapsibilidade do terreno na redução da capacidade de carga. ) Constatou-se uma redução de 51% a 53% nos valores de capacidade de carga anteriormente obtidos. Mas a carga de colapso, ou capacidade de carga na condição inundada, também teve uma majoração importante, aumentando em 45%, 90% e 135% com a cravação de 10%, 20% e 30% do diâmetro da base, respectivamente. Conclui-se que a cravação de tubulões a céu aberto, inicialmente executados com escavação e concretagem in situ, pode ser uma solução interessante em solos colapsíveis.
The belled piles are largely used as fundation for structural elements of residential buildings in small and medium cities in Brazil. The steps of a foundation design is developed in an area previously occupied by old residential buildings. After a careful demolition and clean up process, the challenger is to build the foundations without the danger of harming the adjacent buildings (Division of belled piles on both side and on the bottom). On the design, some specific and some standard procedures are used, which reflect the current practice over the last 10 years, in the Campinas region, with extremely satisfactory results . In porous and collapsible soil, that can be found in many Brazilian regions, these piles usually have presented an inadequate behavior, when the soil is soaked. With a significant elevation on its moisture content, these soils present the collapse settlement, being characterized as collapsible. Since there is already the confirmation of the compacting process efficacy in making the employment of shallow foundations on collapsible soils feasible (CINTRA, 1998), it was decided to study the possible benefits of driving the belled piles on the improvement of the bearing capacity. At the Experimental Foundation Field of USP/São Carlos, two piles were tested. Both piles were 6,00 m long and had a shaft diameter of 0.50 m. The enlarged bases had a diameter of 1.50 m and a height of 0.90 m. The first pile was tested under the non-soaked condition of the soil, on the initial quota of base support, and then with the 0.15 m, 0.30 m and 0.45 driving, which corresponds to 10%, 20%, and 30% of the base diameter, respectively. It was observed that the driving improved the bearing capacity in 42%, 85%, and 127%, respectively. The second pile was tested on a soaked soil, to quantity the collapsibility effect on the reduction of the bearing capacity. A reduction of 51% to 53% on the values of the bearing capacity previously obtained was observed, but the collapse load, also presented an important improvement, increasing 45%, 90%, and 135% with the driving of 10%, 20%, and 30% of the base diameter, respectively. We can conclude that the driving of belled piles, inittially executed with digging and concreting in situ, may be an interesting solution on collapsible soils.

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Alves, Débora Fonseca. "Previsões do comportamento carga-recalque de estaca escavada com polímero." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/156349.

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O evento de previsões do comportamento carga-recalque de uma estaca executada em solo predominantemente arenoso foi apresentado no 8° Seminário de Engenharia de Fundações Especiais e Geotecnia (SEFE8). As previsões utilizaram sondagens CPT, DMT e SPT realizadas no campo experimental de Araquari, em Santa Catarina. A estaca utilizada para o evento foi do tipo escavada com polímero, diâmetro de 100cm e comprimento de 24m. Foram recebidos pelo comitê organizador 73 previsões provenientes de 20 países, com estimativas do comportamento carga-recalque da estaca, da capacidade de carga total, lateral e de ponta e a distribuição de carga ao longo do fuste até a ruptura, definida pelo recalque de 100 mm (w/D = 10%), com um resumo dos métodos e considerações. Os dados das previsões foram comparados aos resultados obtidos em campo pela prova de carga estática da estaca instrumentada. As previsões foram majoritariamente conservadoras e o ensaio mais utilizado para determinação dos parâmetros do solo foi o CPT, tanto no meio acadêmico quanto no prático Diversos métodos foram utilizados, porém mesmo previsões que utilizaram o mesmo método apresentaram variabilidades nos resultados. Baixos valores de desvio na capacidade de carga total não significaram pequenos desvios de lateral e de ponta, mas uma combinação de desvios positivos e negativos desses. A maioria das estimativas subestimou a capacidade lateral e superestimou a de ponta. O método de Verbrugge (1981) foi utilizado em duas das cinco previsões com menores desvios de capacidade total. As curvas carga-recalque e carga-profundidade foram avaliadas quanto aos desvios médios absolutos e formatos, dados pela variância. As curvas carga-recalque com médias de até 10% utilizaram Elementos Finitos e o software UniPile, e o menor valor de variância utilizou Verbrugge (1981). As curvas carga-profundidade com médias de até 10% utilizaram Verbrugge (1981), Randolph e Wroth (1978) e Gwizdala e Steczniewski (2003), e o menor valor de variância utilizou o software UniPile.
The prediction event of load-settlement behavior of a pile built in predominantly sandy soil was presented at the 8th Foundation Engineering Seminar and Special Geotechnical (SEFE8). The predictions used tests of CPT, DMT and SPT accomplished in Araquari experimental field, in Santa Catarina. A bored pile with polymer, diameter of 100cm and length of 24m was the subject of the event. The organizing committee received 73 predictions from 20 countries, with estimates of load-settlement behavior of the pile, the total, shaft and base load capacity and the load distribution along the shaft until failure, defined by settlement of 100 mm (W/D = 10%), with a brief description of methods and considerations. Data from the predictions were compared to the results obtained in the field by static load test of the instrumented pile. The predictions were mostly conservative and the test most used for soil parameters prediction was the CPT, both in academia as in practice. Several methods were used, but even predictions that used the same method showed variability in the results Low error values in the total load capacity not meant small shaft and base errors, but a combination of positive and negative errors of these. Most estimates underestimated the shaft capacity and overestimated the base. The Verbrugge (1981) method was used in two of five predictions with lower errors of total capacity. The curves were analyzed for absolute average deviation and formats, evaluated by the variance. The load-settlement distribution with average up to 10% used Finite Element and UniPile software, and the lowest value of variance used Verbrugge (1981). The load-depth distribution with average up to 10% used Verbrugge (1981), Randolph and Wroth (1978) and Gwizdala and Steczniewski (2003), and the lowest value of variance used the UniPile software.

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43

Freisleben, Michal. "Výpočet zatížení a pevnostní kontrola křídla kluzáku." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2009. http://www.nusl.cz/ntk/nusl-228533.

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44

Mittag, Roland. "Entwicklung Statischer Analysen für AUTOSAR Steuergerätesoftware." Master's thesis, Universitätsbibliothek Chemnitz, 2018. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-232241.

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Durch die Einführung der Systemarchitektur AUTOSAR im automobilen Umfeld, können Applikationen unabhängig von der verwendeten Hardware oder der genutzten Kommunikationssysteme entwickelt werden. Dadurch können Funktionen wieder verwendet werden, was Zeit und Ressourcen einsparen kann. So können Funktionen, die sich etabliert haben, in späteren Entwicklungen durch Anpassung in der Konfiguration genutzt werden ohne dabei den Quellcode zu ändern. Jedoch stellt die große Zahl an Parametern in der AUTOSAR Architektur große Herausforderungen an die Absicherung eines Steuergerätes. Dieser Aspekt wird durch eine meist heterogene Toollandschaft verstärkt. Umso wichtiger ist es, dass während der Entwicklung von AUTOSAR Steuergeräten statische Analysen die Software und die Konfiguration überprüfen, um so die Softwarequalität sicherstellen zu können. In der Masterarbeit werden eine Menge von AUTOSAR spezifischen statischen Analysen für die einzelnen Schichten eines AUTOSAR Steuergerätes entwickelt. Für die Analyse werden Einstellungsdateien (nach Standard und Firmenspezifische) und der Quellcode an sich genutzt. Die Analysen geben optional Korrekturvorschläge an den Entwickler. Die Umsetzung erfolgt in einem C# Prototyp und wird an der Lichtsteuerung des Automotive Demonstrator YellowCar angewendet werden.

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45

Murakami, Daniel Kina. "Novo procedimento para a realização de análise capwap no ensaio de carregamento dinâmico em estacas pré-moldadas." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/3/3145/tde-17062016-144914/.

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Desde a década de 1980 diversos autores apresentaram correlações entre provas de carga estática e ensaios de carregamento dinâmico em estacas. Para uma boa correlação é fundamental que os testes sejam bem executados e que atinjam a ruptura segundo algum critério, como o de Davisson, por exemplo, além de levar em conta o intervalo de tempo entre a execução da prova de carga estática e do ensaio dinâmico, face ao efeito \"set up\". Após a realização do ensaio dinâmico realiza-se a análise CAPWAP que permite a determinação da distribuição do atrito lateral em profundidade, a carga de ponta e outros parâmetros dos solos tais como quakes e damping. A análise CAPWAP é realizada por tentativas através do procedimento \"signal matching\", isto é, o melhor ajuste entre os sinais de força medido pelos sensores e o calculado. É relativamente fácil mostrar que a mesma solução pode ser obtida através de dados de entrada diferentes. Isso significa que apesar de apresentarem cargas mobilizadas próximas o formato da curva da simulação de prova de carga estática, obtida pelo CAPWAP, assim como a distribuição do atrito lateral, podem ser diferentes, mesmo que as análises apresentem \"match quality\" (MQWU) satisfatórios. Uma forma de corrigir o formato da curva simulada do CAPWAP, assim como a distribuição do atrito lateral, é através da comparação com provas de carga estática (PCE). A sobreposição das duas curvas, a simulada e a \"real\", permite a determinação do quake do fuste através do trecho inicial da curva carga-recalque da prova de carga estática, que por sua vez permite uma melhor definição da distribuição do atrito lateral e da reação de ponta. Neste contexto surge o conceito de \"match quality de recalques\" (MQR). Quando a PCE não está disponível, propõe-se efetuar um carregamento estático utilizando o peso próprio do martelo do bate-estaca (CEPM). Mostra-se, através de dois casos de obra, em que estavam disponíveis ensaios de carregamento dinâmico e PCEs, que esse procedimento permite obter uma melhor solução do ponto de vista físico, isto é consistente com as características do subsolo e com a curva carga-recalque da PCE, e não apenas matemático, através da avaliação do \"match quality\" (MQWU).
Since the 1980s a lot of authors showed correlations between static load tests and dynamic load tests on piles. For a good correlation it is necessary a good execution of the load test, also it is necessary to choose a capacity value from the results of the static load test, for example, the Davisson Offset limit load. The time of execution between the static load test and the dynamic load test should be considered because of the set up effect. Dynamic data may be further analyzed by CAPWAP Method to evaluate the soil resistance distribution, the toe resistance, quake and damping values. It is a signal matching method. Its results are based on the \"best possible match\" between computed pile top variable such as the pile top force and its measured equivalent. It is easy to demonstrate almost the same pile capacity on CAPWAP using different soil parameters. It means that even the pile capacity is almost the same, the shape of the pile top load-displacement of the CAPWAP Method and the shaft friction distribution can be different, although all results confirm good match quality. One way to correct the shape of the top loaddisplacement of the CAPWAP Method, as well as the shaft friction distribution, is by comparisson to a static load test. Overlaying both curves, the static load test and the CAPWAP Method, it is possible to determine the shaft quake value on the initial loads on the top load-displacement curve, allowing this way a improvement of the shaft resistance distribution and the toe resistance. In this context arises the concept of \"match quality of settlements\". When the static load test is not avaliabe, this thesis proposes a static load test using the hammer\'s weight of the pile driving machine. It is shown by two case studies that were available static load tests and dynamic load tests, this procedure allows a better solution on physics aspects, this is consistent with the subsoil conditions and the load-settlement curve of the static load test, not only a mathematical solution based on match quality.

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46

Soares, Fábio Lopes. "Análise de provas de carga dinâmica em tubulões a céu aberto no campo experimental de fundações da EESC/USP." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/18/18132/tde-06112006-103725/.

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Apresenta-se o conceito de elemento isolado de fundação em tubulão, e analisa-se 10 provas de carga dinâmica de energia crescente, nos tubulões, considerando as provas de carga estática realizadas anteriormente nos mesmos. Os ensaios são realizados em tubulões a céu aberto, situados em maciço de solo da formação Rio Claro e Itaqueri, no campo experimental de fundações da USP/EESC. As análises baseiam-se em curvas de resistência x deslocamento e gráficos que mostram a evolução da resistência mobilizada com o aumento da energia aplicada, resultantes dos impactos do ensaio dinâmico de energia crescente (metodologia PDA e análises CAPWAP). Analisam-se também a influência da pré-inundação e da variação da sucção do maciço de solos nos ensaios dinâmicos, o efeito do reensaio e a variabilidade nos resultados de ensaios de investigação geotécnica (SPT e CPT), realizados no campo experimental. Os resultados das provas de carga dinâmica de energia crescente mostram que a resposta do sistema isolado de fundação em tubulão é diferente a cada nível de energia aplicada e que a história de carregamento do elemento isolado de fundação é de extrema importância para análise dos ensaios nele realizado.
The concept of an isolated foundation element in large diameter bored pile is presented and 10 dynamic loading tests with increased energy are analysed. The interpretation of the dynamic loading tests has been proceeded with due consideration of the results of static loading tests performed previously. The loading tests have been carried out in large diameter bored piles founded in Rio Claro and Itaqueri soil formation, situated in the experimental foundation field of USP/EESC. The analyses are based on resistance x displacement curves and selected graphics illustrating the development of mobilized resistance with increasing applied energy during a dynamic loading test (PDA methodology and CAPWAP type analysis). The influence of previous inundation in soil mass and suction variation are also analysed, as well as the effect of test repetition and variability in SPT and CPT results. The results obtained with the dynamic loading tests with increasing energy revealed a distinct behaviour of the isolated foundation system for each level of applied energy, showing that the loading history is an aspect of extreme relevance to an adequate analysis of the dynamic tests perfomed.

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47

Petiot, Guillaume. "Contribution à la vérification de programmes C par combinaison de tests et de preuves." Thesis, Besançon, 2015. http://www.theses.fr/2015BESA2045/document.

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La vérification de logiciels repose le plus souvent sur une spécification formelle encodant les propriétés du programme à vérifier. La tâche de spécification et de vérification déductive des programmes est longue et difficile et nécessite une connaissance des outils de preuve de programmes. En effet, un échec de preuve de programme peut être dû à une non-conformité du code par rapport à sa spécification, à un contrat de boucle ou de fonction appelée trop faible pour prouver une autre propriété, ou à une incapacité du prouveur. Il est souvent difficile pour l’utilisateur de décider laquelle de ces trois raisons est la cause de l’échec de la preuve car cette information n’est pas (ou rarement) donnée par le prouveur et requiert donc une revue approfondie du code et de la spécification. L’objectif de cette thèse est de fournir une méthode de diagnostic automatique des échecs de preuve afin d’améliorer le processus de spécification et de preuve des programmes C. Nous nous plaçons dans le cadre de la plate-forme d’analyse des programmes C FRAMA-C, qui fournit un langage de spécification unique ACSL, un greffon de vérification déductive WP et un générateur de tests structurels PATHCRAWLER. La méthode que nous proposons consiste à diagnostiquer les échecs de preuve en utilisant la génération de tests structurels sur une version instrumentée du programme d’origine
Software verification often relies on a formal specification encoding the program properties to check. Formally specifying and deductively verifying programs is difficult and time consuming and requires some knowledge about theorem provers. Indeed, a proof failure for a program can be due to a noncompliance between the code and its specification, a loop or callee contrat being insufficient to prove another property, or a prover incapacity. It is often difficult for the user to decide which one of these three reasons causes a given proof failure. Indeed, this feedback is not (or rarely) provided by the theorem prover thus requires a thorough review of the code and the specification. This thesis develops a method to automatically diagnose proof failures and facilitate the specification and verification task. This work takes place within the analysis framework for C programs FRAMAC, that provides the specification language ACSL, the deductive verification plugin WP, and the structural test generator PATHCRAWLER. The proposed method consists in diagnosing proof failures using structural test generation on an instrumented version of the program under verification

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48

Yucel, Mustafa Can. "Structural Identification, Damage Detection By Non-destructive Tests And Determining Axial Loads In Cables." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12611278/index.pdf.

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Damage and condition identi&
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cation of existing structures using non-destructive tests is a common challenge that has been worked on for a long time. In this study, two di&
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erent methods were developed to &
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nd existing force on cables as well as determine bending characteristics (EI coe&
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cients) of beam like structures (such as bridges). Comparing forces in symmetrically placed cables or against values obtained from design drawings would indicate structural imbalance as well as &
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nding EI coe&
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cients at a number of segments on a bridge girder might indicate weak regions that might possibly have undergone structural damage, having weak connections, lost composite action etc. With the help of the proposed algorithm, the sti&
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ness parameters of bridges can be assessed and the location of any damage that is in the magnitude which can a&
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ect displacement behavior of system can be located. The developed methods are demonstrated using the values analytically obtained from the created models and the e&
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ectiveness of the algorithm is criticized. Furthermore, several damage scenarios on a scaled lab beam was used to test the application using real experimental data
including tests on undamaged beam (for identi&
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cation) and tests on the damaged beam. Additional experiments were conducted on a cable stretched in the laboratory instrumented using a load cell to measure instantaneous axial load on the cable and compare these values against the values obtained from the developed tension measurement device. The results are compared and conclusions are derived.

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49

Málek, Jaroslav. "Zatěžovací zkouška a statické posouzení stropní ŽB konstrukce 1.poloviny 20.století." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2012. http://www.nusl.cz/ntk/nusl-225646.

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This master thesis deals with static load test and static assessment of selected segments of reinforced concrete ceiling construction of the Hennebique system at the Faculty of Arts at Masaryk University in Brno. This thesis contains: the execution of the static load test, the data evaluation of the static load test and the data evaluation of the complementary laboratory testing, geometric orientation of bearing elements, the checking of the ceiling placement in the peripheral position, and the diagnosis of the reinforcing of the construction. This thesis also includes the static assessment according to various standard norm rules and the numerical analysis in ATENA software program.

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50

Tita, Volnei. "Contribuição ao estudo de danos e falhas progressivas em estruturas de material compósito polimérico." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/18/18135/tde-10092015-114215/.

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Neste trabalho buscou-se propor e implementar um modelo de material capaz de prever o comportamento mecânico de estruturas em compósitos poliméricos reforçados (CPR). Inicialmente fez-se um levantamento bibliográfico sobre os modos de danificação intralaminar e falhas interlaminares bem como sobre formas de abordagem (analítica e numérica) para tratar esses problemas. Em seguida, foram apresentadas em detalhes as etapas experimentais executadas, descrevendo todo o procedimento de fabricação dos corpos-de-prova e os resultados obtidos a partir dos ensaios quase-estáticos de tração, compressão, cisalhamento e flexão. Com base nesses resultados e em informações provenientes da literatura, propõem-se alguns modelos de material que foram implementados em sub-rotinas FORTRAN. Tais modelos são posteriormente compilados em conjunto com um programa de elementos finitos (ABAQUS®) a fim de serem avaliados e terem seus parâmetros calibrados. Numa primeira fase, através de simulações computacionais dos ensaios de tração e compressão avaliou-se os modelos de material implementados. Numa segunda fase, os parâmetros foram calibrados tomando como base três estudos de caso (flexão, endentação e teste de impacto) envolvendo seqüências de empilhamento distintas. Após a simulação computacional desses estudos, apresentou-se a proposta de uma metodologia para avaliar problemas de impacto a baixa velocidade em estruturas laminadas. Conclui-se assim que o presente projeto de pesquisa traz contribuições inovadoras, mas também apresenta várias perspectivas de trabalhos futuros.
In this work, material models were proposed to predict the mechanical behavior of composite structures. First of all, it was done a study about damage intra-ply and inter-ply (delamination) on composite materials and about analytical and numerical approaches to solve problems of progressive damage on composite structures was performed. After, many specimens were manufactured and experimental tests (tensile, compression, shear and flexural tests) were carried out. Experimental results and information from literature were used to develop some material models, which were implemented using FORTRAN compiler. These material models were compiled with a commercial finite element program (ABAQUS®) in order to evaluate and calibrate parameters of the models. In the first step, computational simulations of tensile and compression test were carried out to evaluate material models implemented. In the second step, the parameters of the material models were calibrated using three case studies (flexural, indentation and impact test) with some staking sequences. After that, a methodology was proposed to evaluate impact problems on composite structures under low velocity. Therefore, this research project not only shows new contributions but also suggests many future investigations.

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Dissertations / Theses on the topic 'Static Test'

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