To see the other types of publications on this topic, follow the link: Machine testing.

Dissertations / Theses on the topic 'Machine testing'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 dissertations / theses for your research on the topic 'Machine testing.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.

1

Liu, Mu-Hsin. "Multiaxial Fatigue Testing Machine." Ohio University / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1266241731.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Zhang, Zheyu. "Machine Learning for Metamorphic Testing." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-235303.

Full text
Abstract:
Test oracle is a mechanism used to validate all the functionalities ofsoftware under test. However, the lack of test oracle makes the processof software testing difficult. Metamorphic testing is a state of artapproach for automated software testing without test oracles basedon metamorphic relations. Metamorphic relations are a set of propertiesbetween inputs and outputs that a software could have. However,it is usually difficult to identify metamorphic relations for unknownprograms. This thesis aims for automatic generation of metamorphicrelations by utilizing machine learning algorithms with the methodrandom walk kernel using input from control flow graphs. By applyingKanawala et al. [1] previous work in our targeted system environment,we encountered a series of difficulties, which we also describein this thesis. It is important to introduce an alternative solution forour test suite that is working. The performance of our model is evaluatedby different measures including area under the receiver operatingcharacteristic curve and mean squared error. The results show promisingapplications of automatically predicting metamorphic relations forunknown programs. The study was conducted on software system inthe telecommunicaiton domain.<br>Testorakel är en mekanik som används till att avgöra om ett program är korrekt för all funktionalitet i program som testas. Metamorfisk test- ning är en toppmodärn metod för automatiserad programtesting vid saknad testorakel, kan använda metamofiska relationer istället. Tyvärr är det under normala förhållanden svårt att identifiera metamorfiska relationer för okända program. Denna avhandling ämnar därför att automatiskt generera metamorfiska relationer genom att använda ma- skininlärningalgoritmer med kärnmetoden slumpmässig gång och in- data från kontrollflödesgrafer. Metamorfiska relationer är en mängd egenskaper mellan indata och utdata som finns i alla program. Genom att replikera och applicera en tidigare studie av Kanewala et al. [1] i vår egen systemmålmiljö, har vi mött en del svårigheter som vi också be- skriver i denna avhandling. Det är viktigt att introducera alternativa lösningar för vår test svit som fungerar. Prestandan i vår modell ut- värderas av olika mätningar inkluderad AUC och MSE. Våra resultat verkar lovande att använda på automatisk predicerade metamorfiska relationer för okända program. Studien genomfördes på programsystem inom telekommunikationsområdet.
APA, Harvard, Vancouver, ISO, and other styles
3

Berry, Eric Dean. "Randomization testing of machine induced rules." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1995. http://handle.dtic.mil/100.2/ADA304271.

Full text
Abstract:
Thesis (M.S. in Information Technology Management) Naval Postgraduate School, September 1995.<br>"September 1995." Thesis advisor(s): B. Ramesh, William J. Haga. Includes bibliographical references. Also available online.
APA, Harvard, Vancouver, ISO, and other styles
4

Weyrauch, Thomas. "The Paperboard Testing-Machine : Development Process." Thesis, KTH, Hållfasthetslära (Inst.), 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-92639.

Full text
Abstract:
The design of a paperboard testing machine, developed in order to analyse the mechanical behaviour of paperboard during the combined of out-of-plane shear and compressive loading as in the deepdrawing process, is presented. The methodology to design a paperboard testing machine is discussed and the most appropriate concepts are compared and evaluated. The design process is presented in detail, and some pilot tests are performed to give an overview about the functionality of the manufactured prototype.
APA, Harvard, Vancouver, ISO, and other styles
5

Cao, Bingfei. "Augmenting the software testing workflow with machine learning." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/119752.

Full text
Abstract:
Thesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2018.<br>This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.<br>Cataloged from student-submitted PDF version of thesis.<br>Includes bibliographical references (pages 67-68).<br>This work presents the ML Software Tester, a system for augmenting software testing processes with machine learning. It allows users to plug in a Git repository of the choice, specify a few features and methods specific to that project, and create a full machine learning pipeline. This pipeline will generate software test result predictions that the user can easily integrate with their existing testing processes. To do so, a novel test result collection system was built to collect the necessary data on which the prediction models could be trained. Test data was collected for Flask, a well-known Python open-source project. This data was then fed through SVDFeature, a matrix prediction model, to generate new test result predictions. Several methods for the test result prediction procedure were evaluated to demonstrate various methods of using the system.<br>by Bingfei Cao.<br>M. Eng.
APA, Harvard, Vancouver, ISO, and other styles
6

Lee, Dai Gil. "Manufacturing and testing of composite machine tool structures." Thesis, Massachusetts Institute of Technology, 1985. http://hdl.handle.net/1721.1/15265.

Full text
Abstract:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1985.<br>MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING.<br>Vita.<br>Includes bibliographical references.<br>by Dai Gil Lee.<br>Ph.D.
APA, Harvard, Vancouver, ISO, and other styles
7

Bawaskar, Neerja Pramod. "Analog Implicit Functional Testing using Supervised Machine Learning." PDXScholar, 2014. https://pdxscholar.library.pdx.edu/open_access_etds/2099.

Full text
Abstract:
Testing analog circuits is more difficult than digital circuits. The reasons for this difficulty include continuous time and amplitude signals, lack of well-accepted testing techniques and time and cost required for its realization. The traditional method for testing analog circuits involves measuring all the performance parameters and comparing the measured parameters with the limits of the data-sheet specifications. Because of the large number of data-sheet specifications, the test generation and application requires long test times and expensive test equipment. This thesis proposes an implicit functional testing technique for analog circuits that can be easily implemented in BIST circuitry. The proposed technique does not require measuring data-sheet performance parameters. To simplify the testing only time domain digital input is required. For each circuit under test (CUT) a cross-covariance signature is computed from the test input and CUT's output. The proposed method requires a training sample of the CUT to be binned to the data-sheet specifications. The binned CUT sample cross-covariance signatures are mapped with a supervised machine learning classifier. For each bin, the classifiers select unique sub-sets of the cross-covariance signature. The trained classifier is then used to bin newly manufactured copies of the CUT. The proposed technique is evaluated on synthetic data generated from the Monte Carlo simulation of the nominal circuit. Results show the machine learning classifier must be chosen to match the imbalanced bin populations common in analog circuit testing. For sample sizes of 700+ and training for individual bins, classifier test escape rates ranged from 1000 DPM to 10,000 DPM.
APA, Harvard, Vancouver, ISO, and other styles
8

JOSE, MATHEW STEPHEN, and Vijay Francis. "Development, Validation and Implementation of Universal Testing Machine." Thesis, Tekniska Högskolan, Jönköping University, JTH, Industriell produktutveckling, produktion och design, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-50725.

Full text
Abstract:
The thesis paper will be covering the grounds of what, how and why a Universal Testing Machine is used, an alternative to the generic Universal Testing Machinedesigns and how it is built. The primary objective of this thesis work is to designand build a Universal Testing Machine which can handle a load up to 10kN forpolymer materials which is cost effective and modular. The operating system and electronic components are open-source leaving room for further development and compression test. The mechanical properties of material can be measured through tensile test. It gives the the characteristic of tensile strength, yield strength, modulus of elasticity, ductility, resilience, and toughness. The thesis paper covers the use of real timeimage processing for calculating and plotting of a stress strain curve. It also covers the implementation of open source code, using a MATLAB user interface to control, analyse and compile the results of tests done using the new machine. These results have been compared to values obtained from a standard Universal Testing machine and thus validated. As the machine is modular, the parts can be swapped with better components that fits the requirement, leaving the possibility for easy upgrades in the future.
APA, Harvard, Vancouver, ISO, and other styles
9

Beriat, Pelin. "Non-destructive Testing Of Textured Foods By Machine Vision." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12610405/index.pdf.

Full text
Abstract:
In this thesis, two different approaches are used to extract the relevant features for classifying the aflatoxin contaminated and uncontaminated scaled chili pepper samples: Statistical approach and Local Discriminant Bases (LDB) approach. In the statistical approach, First Order Statistical (FOS) features and Gray Level Cooccurrence Matrix (GLCM) features are extracted. In the LDB approach, the original LDB algorithm is modified to perform 2D searches to extract the most discriminative features from the hyperspectral images by removing irrelevant features and/or combining the features that do not provide sufficient discriminative information on their own. The classification is performed by using Linear Discriminant Analysis (LDA) classifier. Hyperspectral images of scaled chili peppers purchased from various locations in Turkey are used in this study. Correct classification accuracy about 80% is obtained by using the extracted features.
APA, Harvard, Vancouver, ISO, and other styles
10

Stander, Melchior. "Development of an intermediate strain rate compression testing machine." Master's thesis, University of Cape Town, 2014. http://hdl.handle.net/11427/9131.

Full text
Abstract:
Includes bibliographical references.<br>The further development of the wedge bar Intermediate Strain rate Tester (IST) presented by Cloete and Oxtoby [1] is presented in this dissertation. The concept uses a wedge mechanism to deform 5 mm diameter, 5 mm long specimens at strain rates in the region of 10 s, up to strains of 30. As impact principles are used to start and stop the experiment, it takes less than 1 of the testing duration to reach testing speed and to stop the experiment. The kinetic energy stored in the wedge bar helps ensure a near constant loading rate over the duration of the experiment. The yield stress is captured at above 80 of the average strain rate for the experiment for most of the materials investigated. The design work focuses primarily around the design of the new load-frame, load-cell, loading platforms and wedge bar displacement sensor. Finite Element Analysis (FEA) was used to investigate the dynamic response of the IST and modify the design of components where necessary. The modifications made the load-frame and load-cell result in a significant improvement in the quality of the measured signals. The wedge bar displacement sensor performed well. The back pressure driven loading concept shows potential but needs more development before it is suitable for routine testing. A range of common engineering materials was tested at quasi static, intermediate and high strain rates and compared to the results found in the literature. The results match well, however, friction effects dominate the large strain response of the metal specimens. In its current configuration the IST is used effective for testing polymers up to large strains as well as yield stress and small strain measurement of metals. For materials for which specimen friction effects are a problem, interrupted tests can be used to extend the maximum strain achievable.
APA, Harvard, Vancouver, ISO, and other styles
11

Alcantara, Alcover Enrique. "Differences between machine and human testing of shock absorbing systems." Thesis, Middlesex University, 2000. http://eprints.mdx.ac.uk/6633/.

Full text
Abstract:
This thesis documents a study on the sources of the differences found between results from machine and walking testing of shock absorbing systems. A complex programme of experiments was conducted at the Institute of Biomechanics of Valencia to explore the four most outstanding statements proposed with this respect: 1. - No accurate simulation of impacts by machine test. This was investigated by comparing results from testing materials simulating impact forces with results from walking tests. 2. - In use materials degrade and their properties change and existing machine testing methods could not replicate material properties during walking. A new testing method was developed to measure the recovery ability of materials by simulating plantar pressures and results compared with walking tests. 3. - Shoe effect on walking kinematics and heel pad confinement has greater influence on shock absorption than material properties. An instrumented pendulum was developed to study the heel pad. Insole materials were evaluated in walking tests, in pendulum tests and in different machine testing including the new method developed simulating plantar pressures and the results compared. 4. - Accommodation to impact conditions occurs according to a controlled proprioceptive feedback model. Accommodation, impact perception, comfort, walking and passive biomechanical variables and material properties were studied in relation to system's input, output and goal. Accurate simulation of impacts improved the ability of machine test to predict the walking performance of materials, but not upper body shock transmission. Properties of materials such as recovery ability, stiffness and hardness play an important role in concepts and passive interaction but mainly by influencing accommodation. Accommodation was identified as the source of differences of results between machine and walking tests of shock absorbing materials. The human body was described as comprising two independent mechanical systems: One system, governed by the elasticity and hardness of materials, it is defined by impact forces and accelerations that are inversely related to upper body transmission and control the perceived impact through foot position and knee bend. The other system is defined by heel pad stiffness, insole properties at initial loading and passive interaction that regulate upper body shock transmission by ankle inversion for comfort control. Passive interaction is defined in this thesis as the mechanical coupling between insole and heel pad that determines the properties of the system either through heel pad confinement or compression. Machine tests appear to predict results with respect to the first system but not the second, which required passive human testing. For insole use, high-energy absorption materials are preferred. These are capable of increasing elastic deformation to reduce impact forces and accelerations without increasing initial-maximal stiffness by passive interaction thus avoiding any increase of head transmission due to accommodation. Heel pad properties were described by three mechanical components accounting for 93.08% of total variance: These are an elastic component, a viscoelastic component and a component related to elastic deformation at low stiffness. Differences were found between shod and barefoot test results. With barefoot there was an initial low stiffness (18-50 kNm*1) response that was not evident in the shod tests which showed elastic deformation related to final stiffness. With barefoot, the elastic component accounted for impact forces variance (> 70%) and initial deformation component for peak force time (> 60%), while shod impact forces were related mainly to the elastic deformation component (> 60%) whereas rate of loading and acceleration were related to the initial-maximal stiffness component (>20%). Differences in heel pad mechanics due to age, gender and obesity were observed. Although the heel pad properties degraded with age, losses appeared to be compensated by obesity.
APA, Harvard, Vancouver, ISO, and other styles
12

Goodall, Shane. ""Harness Shakedown" Flight Bus Harness Testing Using the CKT Machine." Digital Commons at Loyola Marymount University and Loyola Law School, 2012. https://digitalcommons.lmu.edu/etd/391.

Full text
Abstract:
At the Boeing Satellite Development Center, all programs must follow the same test flow through the factory. First the units are built, tested, and delivered for sub system level integration. There are units built for the bus module and units built for the payload module. Both sub systems are built in different locations and have their own core teams. Once the sub systems are properly integrated, they will then travel to the next test phase of the factory which is known as Integrated Vehicle Testing (IVT). During IVT, both the bus and payload modules are integrated to make one system. This system will travel through the factory and will be tested to make sure that all requirements are met. Once all requirements are validated and verified, the spacecraft is now ready for launch and delivery to the customer. There are hundreds of tests that need to take place throughout the spacecrafts life in the factory. The purpose of these tests is to make sure that a requirement from the customer is met one way or another. Thousands of man hours are budgeted for testing the satellite during its journey through the factory. At an average engineering cost of $200 per hour, this total dollar value for requirements validation and verification can get very expensive. One of the tests in particular is called "Harness Shakedown." This test is conducted to make sure that all the harness wiring in the bus module is wired correctly per the released wire list. These wires can be used for telemetry and control, power to units, signal wires, etc. The way that the test is currently conducted is all done manually using break out boxes, break out cables, digital volt meters, and power supplies. This is an inefficient way of doing the test. This test can be leaned out using systems engineering practices and finding better ways for doing this test to bring value to the customer. The most expensive cost to a program is engineering labor. Systems engineering can help in this test by using the systems engineering process milstd- 499B. This will be used to ensure that the requirements are good and can be fulfilled through the new way of testing. Lean systems engineering will play a large role in finding waste in the test and how to eliminate this non-value added waste. Understanding risk that can occur and ways to manage that risk, is key when fulfilling these requirements. Performing trade studies on how to do this test will help in making the proper engineering decision for the best way of doing the test while again, focusing on added value to the program.
APA, Harvard, Vancouver, ISO, and other styles
13

Damasceno, Carlos Diego Nascimento. "Evaluating finite state machine based testing methods on RBAC systems." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/55/55134/tde-11112016-101158/.

Full text
Abstract:
Access Control (AC) is a major pillar in software security. In short, AC ensures that only intended users can access resources and only the required access to accomplish some task will be given. In this context, Role Based Access Control (RBAC) has been established as one of the most important paradigms of access control. In an organization, users receive responsibilities and privileges through roles and, in AC systems implementing RBAC, permissions are granted through roles assigned to users. Despite the apparent simplicity, mistakes can occur during the development of RBAC systems and lead to faults or either security breaches. Therefore, a careful verification and validation process becomes necessary. Access control testing aims at showing divergences between the actual and the intended behavior of access control mechanisms. Model Based Testing (MBT) is a variant of testing that relies on explicit models, such as Finite State Machines (FSM), for automatizing test generation. MBT has been successfully used for testing functional requirements; however, there is still lacking investigations on testing non-functional requirements, such as access control, specially in test criteria. In this Master Dissertation, two aspects of MBT of RBAC were investigated: FSM-based testing methods on RBAC; and Test prioritization in the domain of RBAC. At first, one recent (SPY) and two traditional (W and HSI) FSM-based testing methods were compared on RBAC policies specified as FSM models. The characteristics (number of resets, average test case length and test suite length) and the effectiveness of test suites generated from the W, HSI and SPY methods to five different RBAC policies were analyzed at an experiment. Later, three test prioritization methods were compared using the test suites generated in the previous investigation. A prioritization criteria based on RBAC similarity was introduced and compared to random prioritization and simple similarity. The obtained results pointed out that the SPY method outperformed W and HSI methods on RBAC domain. The RBAC similarity also achieved an Average Percentage Faults Detected (APFD) higher than the other approaches.<br>Controle de Acesso (CA) é um dos principais pilares da segurança da informação. Em resumo, CA permite assegurar que somente usuários habilitados terão acesso aos recursos de um sistema, e somente o acesso necessário para a realização de uma dada tarefa será disponibilizado. Neste contexto, o controle de acesso baseado em papel (do inglês, Role Based Access Control - RBAC) tem se estabelecido como um dos mais importante paradigmas de controle de acesso. Em uma organização, usuários recebem responsabilidades por meio de cargos e papéis que eles exercem e, em sistemas RBAC, permissões são distribuídas por meio de papéis atribuídos aos usuários. Apesar da aparente simplicidade, enganos podem ocorrer no desenvolvimento de sistemas RBAC e gerar falhas ou até mesmo brechas de segurança. Dessa forma, processos de verificação e validação tornam-se necessários. Teste de CA visa identificar divergências entre a especificação e o comportamento apresentado por um mecanismo de CA. Teste Baseado em Modelos (TBM) é uma variante de teste de software que se baseia em modelos explícitos de especificação para automatizar a geração de casos testes. TBM tem sido aplicado com sucesso no teste funcional, entretanto, ainda existem lacunas de pesquisa no TBM de requisitos não funcionais, tais como controle de acesso, especialmente de critérios de teste. Nesta dissertação de mestrado, dois aspectos do TBM de RBAC são investigados: métodos de geração de teste baseados em Máquinas de Estados Finitos (MEF) para RBAC; e priorização de testes para RBAC. Inicialmente, dois métodos tradicionais de geração de teste, W e HSI, foram comparados ao método de teste mais recente, SPY, em um experimento usando políticas RBAC especificadas como MEFs. As características (número de resets, comprimento médio dos casos de teste e comprimento do conjunto de teste) e a efetividade dos conjuntos de teste gerados por cada método para cinco políticas RBAC foram analisadas. Posteriormente, três métodos de priorização de testes foram comparados usando os conjuntos de teste gerados no experimento anterior. Neste caso, um critério baseado em similaridade RBAC foi proposto e comparado com a priorização aleatória e baseada em similaridade simples. Os resultados obtidos mostraram que o método SPY conseguiu superar os métodos W e HSI no teste de sistemas RBAC. A similaridade RBAC também alcançou uma detecção de defeitos superior.
APA, Harvard, Vancouver, ISO, and other styles
14

Altalabani, Osama. "An automatic machine-learning framework for testing service-oriented architecure." Thesis, Kingston University, 2014. http://eprints.kingston.ac.uk/32198/.

Full text
Abstract:
Today, Service Oriented Architecture (SOA) systems such as web services have the advantage of offering defined protocol and standard requirement specifications by means of a formal contract between the service requestor and the service provider, for example, the WSDL (Web Services Description Language) , PBEL (Business Process Execution Language), and BPMN (Business Process Model and Notation). This gives a high degree of flexibility to the design, development, Information Technology (IT) infrastructure implementation, and promise a world where computing resources work transparently and efficiently. Furthermore, the rich interface standards and specifications of SOA web services (collectively referred to as the WS-* Architecture) enable service providers and consumers to solve important problems, as these interfaces enable the development of interoperable computing environments that incorporate end-to-end security, reliability and transaction support, thus, promoting existing IT infrastructure investments. However, many of the benefits of SOA become challenges for testing approaches and frameworks due to their specific design and implementation characteristics, which cause many testability problems. Thus, a number of testing approaches and frameworks have been proposed in the literature to address various aspects of SOA testability. However, most of these approaches and frameworks are based on intuition and not carried out in a systematic manner that is based on the standards and specifications of SOA. Generally, they lack sophisticated and automated testing, which provide data mining and knowledge discovery in accordance with the system based on SOA requirements, which consequently would provide better testability, deeper intelligence and prudence. Thus, this thesis proposes an automated and systematic testing framework based on user requirements, both functional and non-functional, with support of machine-learning techniques for intelligent reliability, real-time monitoring, SOA protocols and standard requirements coverage analysis to improve the testability of SOA-based systems. This thesis addresses the development, implementation, and evaluation of the proposed framework, by means of a proof-of-concept prototype for testing SOA systems based on the web services protocol stack specifications. The framework extends to intelligent analysis of SOA web service specifications and the generation of test cases based on static test analysis using machine-learning support.
APA, Harvard, Vancouver, ISO, and other styles
15

Rönn, Mattias. "Symvex : A Symbolic Execution System for Machine Code." Thesis, Linköpings universitet, Databas och informationsteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-124181.

Full text
Abstract:
This thesis is a part of an ongoing research project at Link ̈oping University. The goal of the thesis work is to design and implement a prototype for a symbolic execution system that scales well with larger programs and is capable of performing symbolic execution on machine code. For this reason we have analyzed the current state of symbolic executors that are able to perform symbolic execution on machine code to see if we could use that implementation as base for our prototype. We wanted to know if any of the existing systems scaled well with large software. We found that neither of the existing systems worked well with the real life software in our evaluation. Furthermore, even if it would have been possible to fix one of the existing systems, the time required to figure out the faults in their implementation would most likely have been too great. For this reason we decided to create an implementation of our own from scratch. However, we did note that some approaches in the existing systems seemed to work better with large software. Specifically saving as little state as possible about the program seemed favorable. Armed with the knowledge gained from the analysis, we managed to implement a system that compared quite well with the existing systems. Our system was able to execute all the real-life programs used in our tests, but unfortunately had some issues with high memory usage for certain programs. In order to lessen the problem with high memory usage, we present and discuss several potential ways to mitigate this issue.
APA, Harvard, Vancouver, ISO, and other styles
16

Grubic, Stefan. "Online monitoring of turn insulation deterioration in mains-fed induction machines using online surge testing." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/41131.

Full text
Abstract:
The development of an online method for the early detection of a stator turn insulation deterioration is the objective of the research at hand. A high percentage of motor breakdowns is related to the failure of the stator insulation system. Since most of the stator insulation failures originate in the breakdown of the turn-to-turn insulation, the research in this realm is of great significance. Despite the progress that has been made in the field of stator turn fault detection methods, the most popular and the best known ones are still limited to the detection of solid turn faults. The time span between a solid turn fault and the breakdown of the primary insulation system can be as short as a few seconds. Therefore, it is desirable to develop a method capable of detecting the deterioration of the turn insulation as early as possible and prior to the development of a solid turn fault. The different stresses that cause the aging of the insulation and eventually lead to failure are described as well as the various patterns of an insulation failure. A comprehensive literature survey shows the methods presently used for the monitoring of the turn insulation. Up to now no well-tested and reliable online method that can find the deterioration of the turn insulation is available. The most commonly used turn insulation test is the surge test, which, however, is performed only when the motor is out of service and disconnected from the supply. So far no research at all has been conducted on the application of an online surge test. The research at hand examines the applicability of the surge test to an operating machine. Various topologies of online surge testing are examined with regard to their practicability and their limitations. The most practical configuration is chosen for further analysis, implementation and development. Moreover, practical challenges are presented by the non-idealities of the induction machine like the eccentricity of the rotor and the rotor slotting, and have to be taken into account. Two solutions to eliminate the influence of the rotor position on the surge waveform are presented. Even though the basic concepts of online surge testing can be validated experimentally by a machine with a solid turn fault, it is preferable to use a machine with a deteriorated turn insulation. Therefore, a method, which does not require complex and expensive hardware, to experimentally emulate the turn insulation breakdown is implemented. The concepts at any stage of the work are supported by simulations and experimental results. In addition, the theory of surge testing is further developed by giving new definitions of the test's sensitivity, i.e., the frequency sensitivity and the error area ratio (EAR) sensitivity.
APA, Harvard, Vancouver, ISO, and other styles
17

Chen, Anyuan. "Investigation of Permanent Magnet Machines for Downhole Applications : _ Design, Prototype and Testing of a Flux-Switching Permanent Magnet Machine." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for elkraftteknikk, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-11829.

Full text
Abstract:
The current standard electrical downhole machine is the induction machine which is relatively inefficient. Permanent magnet (PM) machines, having higher efficiencies, higher torque densities and smaller volumes, have widely employed in industrial applications to replace conventional machines, but few have been developed for downhole applications due to the high ambient temperatures in deep wells and the low temperature stability of PM materials over time. Today, with the development of variable speed drives and the applications of high temperature magnet materials, it is increasingly interesting for oil and gas industries to develop PM machines for downhole applications. Recently, some PM machines applications have been presented for downhole applications, which are normally addressed on certain specific downhole case. In this thesis the focus has been put on the performance investigation of different PM machines for general downhole cases, in which the machine outer diameter is limited to be small by well size, while the machine axial length may be relatively long. The machine reliability is the most critical requirement while high torque density and high efficiency are also desirable. The purpose is to understand how the special constraints in downhole condition affect the performances of different machines.  First of all, three basic machine concepts, which are the radial, axial and transverse flux machines, are studied in details by analytical method. Their torque density, efficiency, power factor and power capability are investigated with respect to the machine axial length and pole number. The presented critical performance comparisons of the machines provide an indication of machines best suitable with respect to performance and size for downhole applications. Conventional radial flux permanent magnet (RFPM) machines with the PMs on the rotor can provide high torque density and high efficiency. This type of machine has been suggested for several different downhole applications. Flux-switching PM (FSPM) machines, which have the PMs located on the stator and are therefore more reliable, can theoretically also exhibit high torque density and relatively high efficiency. This thesis has put an emphasis on studying this type of machine. Two FSPM machines have been investigated in detail and compared by analytical method, FEM simulation and prototype measuremens. Their operating principle and important design parameters are also presented. A lumped parameter magnetic circuit model for designing a high-torque FSPM machine is newly introduced and the designed machine is verified by FEM simulations. A prototype machine with an outer diameter of 100 mm and an axial length of 200 mm is built in the laboratory and tested at room temperature. Based on that, the machine performance at an ambient temperature of 150°C is also predicted. The results show that the FSPM machine can provide a high torque density with slight compromise of efficiency and power factor. Choosing a proper machine type is significantly dependent on the application specifications. The presented results in this thesis can be used as a reference for selecting the best machine type for a specific downhole case.
APA, Harvard, Vancouver, ISO, and other styles
18

Purmonen, Sami, and Paul Griffin. "Testing Stock Market Efficiency Using Historical Trading Data and Machine Learning." Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-166583.

Full text
Abstract:
Stock forecasting is a problem that is important in finance because it aids investors in financial decision making. According to the efficient market hypothesis stock markets are efficient in such a way that it's impossible to gain excess returns over the market by making decisions based on current available information. This paper evaluates the usage of machine learning algorithms and historical trading data for stock price prediction combined with investment strategies in order to test the efficient market hypothesis. The results show that none of the tested machine learning algorithms managed to gain excess returns over the market which confirms the efficient market hypothesis.
APA, Harvard, Vancouver, ISO, and other styles
19

Sullivan, P. J. "Design and development of a computer based multi-purpose material test machine." Thesis, Coventry University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233849.

Full text
APA, Harvard, Vancouver, ISO, and other styles
20

Shankarnarayanan, Sundar. "Cost Optimization Solution&Testing Strategy for HMI (Human Machine Interface) Products." Thesis, KTH, Industriell produktion, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-55465.

Full text
Abstract:
The automotive sector has been the most happening industry in terms of development ever since its creation. With markets emerging across the globe in the automotive sector there are newer challenges in terms of providing new products at lesser cost but without compromising on quality. Testing cost of electromechanical components (HMI) is high and which in turn has a direct impact on the final price of the product, which they are selling it to their customers. One way to counter this issue is to outsource. The aim of this thesis is to actually provide business intelligence where by the midsize segmented automotive suppliers are benefited and the cost of testing can be reduced. The product in focus here is an electromechanical component (HMI) for commercial vehicles. The main contribution in this thesis has been the analysis &amp; implementation of the outsourcing strategy. There were two approaches one being a theoretical approach where a market research was done to get an overview of the current trend and studying the demands of different customer for testing. The second half has been practicality implementing this data collected. Here no assumptions have been taken and the data collected has been obtained purely based on interaction with various test vendors across Europe. Cost optimization analysis was further done in order to arrive at a conclusion of preferred suppliers. Also another strategy used was by investigating possibilities for making some test in house and defining standardized test plan procedures for them. Thereby providing an overall strategy for testing with cost optimization as the main focus also leading to an edge over their competitors and increasing their market share.
APA, Harvard, Vancouver, ISO, and other styles
21

Edirisinghe, Ajith A. G. "Stress relaxation testing with a novel machine using rapid application of load." Thesis, Loughborough University, 1998. https://dspace.lboro.ac.uk/2134/10324.

Full text
Abstract:
It has long been desirable to conduct Stress Relaxation measurements over shorter test times. The problem has been to achieve a short well-characterised loading phase and to obtain the first stress relaxation reading soon after the completion of loading. Although it is possible to programme a standard computer-controlled mechanical tester to acquire readings down to very short time periods, uncertainty of achieving the correct deformation at very high loading rates restricts its use. The Hounsfield Test Equipment company in collaboration with the Loughborough University has produced a compression tester intended to overcome the problem. This new machine is capable of giving compressive strain rates from 0.1 nun/min upto 250 mm/min (SLOW MODE) and one extremely high compressive strain rate of 2 m/sec (120,000 mm/min - FAST MODE) The machine was employed initially to produce sets of stress relaxation curves to investigate possible machine errors. The main error found was incorrect compression produced by the tester; it varied from 20% to 27% instead of the desired 25%. After this and some smaller errors were identified, several precautionary actions were taken to compensate for them. The compensation techniques permitted progress to a study of three different Natural Rubber compounds at three different temperatures using several different compressive strains in both slow and fast modes. A clear difference in the residual forces between fast mode test curves and slow mode test curves has been identified and the possible reasons for differences are discussed. It has been shown that the relaxation curves in slow mode can be represented by two linear portions representing two different relaxation processes. On the each relaxation process the effect of the rate of compressive strain and the temperature of the material is discussed.
APA, Harvard, Vancouver, ISO, and other styles
22

Milthorpe, Thomas Edward. "Development of advanced control strategies for a dynamic triaxial soil testing machine." Thesis, University of Reading, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.590131.

Full text
Abstract:
As civil engineering projects become increasingly ambitious, the earthworks that form a significant part of these projects become increasingly critical. Geotechnical engineering is concerned with the measurement , modelling and simulation of soil under various conditions for the application within civil engineering. In triaxial testing, an actuator applies a force or displacement to a soil sample. Dynamic triaxial testing is concerned with applying forces conforming to a rapidly changing pattern. The simplest case is concerned with applying a force in a sinusoidal pattern. The accuracy of models produced during triaxial testing depends largely on the accuracy of the equipment used for testing. As such, the control of the applied force is of great importance. The response of the soil sample directly influences the closed loop behaviour of the system. The soil sample response is unknown at the start of the test , can vary throughout a test and depends on various parameters, many of which are unobservable. This research investigates the issues faced in developing accurate control of dynamic triaxial testing equipment. Models of the load frame and various nonlinear soil sample responses are built for the purpose of simulation and controller design. Various control strategies are developed, implemented and tested, including the use of PID control, adaptive repetitive control and sliding mode control techniques. The recursive least squares algorithm is investigated and used for online identification in order to compensate for unknown and time varying plant parameters. Simulation and testing methods are investigated and several control methods are tested in simulation, on the target triaxial load frame using and finally using embedded processing hardware. Development and implementation techniques are also used including rapid prototyping and hardware-in-the-loop testing.
APA, Harvard, Vancouver, ISO, and other styles
23

Grondoudis, Andreas. "X-machine based specification and design for testing of the CATV protocol." Thesis, University of Sheffield, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340170.

Full text
APA, Harvard, Vancouver, ISO, and other styles
24

Ames, Nicoli M. (Nicoli Margret) 1978. "Design and use of a fixed-end low-load material testing machine." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/33156.

Full text
Abstract:
Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2000.<br>This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.<br>Includes bibliographical references (leaf 25).<br>The purpose of this low-load material testing machine is to provide students an opportunity to perform basic material tests on their own instead of watching a lab technician, thus improving the student's lab experience. The machine proposed is small, low cost, and easy to manufacture, assemble, and operate. Its design is based on a compound flexure mechanism that provides rectilinear motion for uniaxial tension and compression tests. It is actuated by a voice coil and displacement is measured using strain gauges. This thesis outlines some of the basic theory involved in the design and use of this low-load machine. Then it details calibration routines and tension testing procedures. Next, it analyzes results from tension tests. Then it discusses a possible source of error found in the tension tests, a lack of rigidity in the apparatus. Finally, it provides a reasonable solution to the rigidity issue and suggests further testing of the new apparatus before it is available for student use.<br>by Nicoli M. Ames.<br>S.B.
APA, Harvard, Vancouver, ISO, and other styles
25

Ingvarsson, Sanne. "Using Machine Learning to Learn from Bug Reports : Towards Improved Testing Efficiency." Thesis, Linköpings universitet, Institutionen för datavetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-156711.

Full text
Abstract:
The evolution of a software system originates from its changes, whether it comes from changed user needs or adaption to its current environment. These changes are as encouraged as they are inevitable, although every change to a software system comes with a risk of introducing an error or a bug. This thesis aimed to investigate the possibilities of using the description of bug reports as a decision basis for detecting the provenance of a bug by using machine learning. K-means and agglomerative clustering have been applied to free text documents by using Natural Language Processing to initially divide the investigated software system into sub parts. Topic labelling is further on performed on the found clusters to find suitable names and get an overall understanding for the clusters.Finally, it was investigated if it was possible to find which cluster that were more likely to cause a bug from certain clusters and should be tested more thoroughly. By evaluating a subset of known causes, it was found that possible direct connections could be found in 50% of the cases, while this number increased to 58% if the cause were attached to clusters.
APA, Harvard, Vancouver, ISO, and other styles
26

Qudus, Abdul. "Automated Validation of User Equipment Connection States." Thesis, Linköpings universitet, Institutionen för datavetenskap, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-113889.

Full text
Abstract:
Telecom today has become an essence of life. Everywhere we see people using their smart phones for calling, checking email or accessing internet. To handle all these kinds of services without any intrusion is a very challenging task. This study deals with software testing which helps to ensure the quality of service to the end user. Software testing is an essential part in the software development process. Software development for telecom domain might not look as safety critical as of an airplane or nuclear reactor but it is arguably more complex. The main focus of this study is to provide automation to the unit testing of different types of radio connections that can be assigned to the end user based on the requested service and capacity of the 3G network. This research is sponsored by Ericsson to improve the testing of User Equipment Radio Connection Handling system that controls multiple possible radio connection configurations. This research attempts to identify and test all possible transitions between radio connection states. This will improve the existing manual state testing system, where changes in connection states cause dramatic impacts on test fixtures. As a solution, an automatic test case executor is proposed that generates possible transitions, which are later executed and verified automatically.
APA, Harvard, Vancouver, ISO, and other styles
27

Anne, Aditya. "A WEB BASED MACHINE LEARNING UTILITY." University of Akron / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=akron1196644291.

Full text
APA, Harvard, Vancouver, ISO, and other styles
28

Mdletshe, Zamavangeli. "Design and manufacturing of a temperature controlled chamber for a tensile testing machine." Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2570.

Full text
Abstract:
Thesis (MTech (Mechanical Engineering))--Cape Peninsula University of Technology, 2017.<br>Material testing is an important test to researchers in material science fields and other engineering related fields. This is the base for material evaluation prior to the application. This test is used in the engineering field to determine the strength of materials which is an aspect of assigning materials to different functions. The uniaxial tensile testing of material is the most common form of testing the strength of metallic material - usually to investigate whether or not the material is worthy of the intended application. Material testing is normally performed under uncontrolled conditions in most laboratories. Numerous attempts had been previously made in attempt to control the temperature conditions when performing the tensile test on special materials such as shape memory alloys (SMA) and other smart materials. Various methods had been employed to control the temperature during tensile testing, methods such as induction heating, warm liquid baths, etc. The aim of this study was to develop a temperature controlled environment for the Houndsfield tensile testing machine which is found at the Cape Peninsula University of Technology in the Mechanical Engineering Department workshop. This was achieved through designing and manufacturing of a thermally controlled chamber -better known as a furnace. This chamber was tested for the optimal combination of proportional, integral and derivative parameters which were tuned on the proportional integral derivative (PID) controller. Performing the tensile test under controlled thermal conditions will allow the analysis of SMAs and other materials behaviour at different temperatures. With the aid of the manufactured chamber, the superior features of the SMA will be able to be studied. The manufactured thermal chamber which is electrically powered is insulated with a special ceramic refractory material to prevent the heat from escaping the chamber. The PID controller was used to control the temperature and heating elements act as the heat source. The manufactured chamber could withstand the maximum temperature 350oC that it was initially designed for. However, the challenge of having the specimen to be tested fully inside the chamber was overcame by designing specimen connectors that connected the specimen to the tensile testing machine. Tensile tests were conducted on the SMA wire at room temperature and other various controlled temperatures and different behaviours were observed on the stress-strain graphs.
APA, Harvard, Vancouver, ISO, and other styles
29

SANCHEZ, ELEAZAR CRISTIAN MEJIA. "DEVELOPMENT OF A TENSION-TORSION FATIGUE TESTING MACHINE TO EVALUATE INCREMENTAL PLASTICITY MODELS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2014. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=35541@1.

Full text
Abstract:
PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO<br>COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR<br>FUNDAÇÃO DE APOIO À PESQUISA DO ESTADO DO RIO DE JANEIRO<br>PROGRAMA DE EXCELENCIA ACADEMICA<br>BOLSA NOTA 10<br>A avaliação experimental de modelos de plasticidade incremental e a predição da vida à fadiga sobre cargas combinadas requer o uso de máquinas de testes multiaxiais. Neste trabalho é desenvolvida uma máquina tração-torção (MTT) para avaliar modelos de plasticidade incremental. Este sistema eletromecânico utiliza como atuadores principais dois motores de corrente contínua conectados a caixas de redução para gerar os carregamentos de tração axial e/ou torção. O projeto da MTT compreende a análise de sua integridade estrutural, seu dimensionamento, e o cálculo da vida à fadiga de seus principais componentes; o projeto e desenvolvimento de uma célula tração-torção (LTC - load torque cell); o desenvolvimento e implementação das técnicas de controle; e finalmente sua construção e avaliação. Uma técnica de controle PID por modos deslizantes (PID Sliding Mode control) foi especialmente desenvolvida para esta máquina, consistindo em aplicar um sinal de controle descontínuo que força o sistema a deslizar ao longo de uma superfície de convergência. Esta técnica de controle tem a capacidade de controlar continuamente a força axial e/ou o torque aplicado ao corpo de prova de maneira independente, o que permite gerar histórias de cargas não-proporcionais. Os métodos de controle são implementados em uma plataforma computacional em tempo real CompactRio. Deste modo, é possível gerar uma máquina de ensaios de fadiga multiaxial compacta, de fácil manuseio, que não precise de um sistema de controle complexo, e a um baixo custo. A máquina tração-torção foi projetada para atender a uma ampla gama de ensaios de fadiga multiaxial, com uma capacidade de força axial máxima de mais ou menos 200 kN e torque máximo de mais ou menos 1300 N.m. O desempenho da MTT foi avaliado experimentalmente através de ensaios de plasticidade incremental. Para tanto, foram usados corpos de prova de tração-torção para medir seus comportamentos sobre cargas multiaxiais. Ensaios de encruamento não-proporcional, ratcheting (fluência cíclica) multiaxial e ratcheting uniaxial foram realizados em corpos de prova de aço inox 316, aço 1020, alumínio 7075 e alumínio 6063 na MTT, assim como em uma máquina Instron de 100 kN. Um simulador de plasticidade incremental para carregamentos de tração-torção foi desenvolvido, incorporando o modelo de encruamento cinemático não-linear de Jiang-Sehitoglu, e o modelo incremental de encruamento não-proporcional de Tanaka. Os parâmetros do material foram calibrados a partir de ensaios experimentais, permitindo que as simulações fossem capazes de prever o comportamento do material sobre diferentes histórias de carregamento, assim como as taxas de encruamento não-proporcional e de ratcheting. Os experimentos e simulações confirmaram tanto a adequabilidade da MTT desenvolvida, quanto do simulador de plasticidade incremental implementado, baseado nos modelos não-lineares de Jiang-Sehitoglu e Tanaka.<br>The experimental evaluation of incremental plasticity models and fatigue life prediction under combined loads requires the use of multiaxial testing machines. In this work, an axial-torsion machine (MTT) was developed to evaluate incremental plasticity models. This electromechanical system uses as a main actuators two DC motors connected to gearboxes to generate the axial and/or torsion loads. The design of axial-torsion machine comprises the analysis of its structural integrity, its dimensioning and fatigue life prediction its major components; the design and development of a load torque cell – LTC; the development and implementation of control techniques, and finally, its construction and its performance evaluation. A PID Sliding Model control technique has been specially developed for this machine, which consists in applying a discontinuous control signal that forces the system to slide along a surface convergence. This control technique has the ability to control the axial force and/or torsion applied to specimen test in an independent manner, which allows to generate a non-proportional loading histories. The control methods are implemented on a computing platform in real time CompactRio. Thus, it s possible to developed a compact multiaxial fatigue testing machine, easy to handle, which does not require a complex control system, and at a low cost. The tensiontorsion machine was designed to meet a wide range of multiaxial fatigue tests, with a maximum capacity of axial force of more or less 200 kN and torque of more or less 1300 N.m. The MTT performance was evaluated experimentally by incremental plasticity testing. For this purpose, tensile / torsion specimens were used to measure their behavior under multiaxial loads. Testing of non-proportional hardening, multiaxial ratcheting and uniaxial ratcheting (cyclic creep) were performed on specimens of 316 stainless steel, 1020 steel, 7075 aluminum and 6351T6 aluminum in the MTT, as well as a Instron Machine of more or less 100 kN. A simulator of incremental plasticity to tensile-torsion loads has been developed, incorporating the non-linear kinematic hardening model of Jiang-Sehitoglu, and non-proportional hardening model of Tanaka. The material parameters were calibrated using experimental tests, allowing the simulations to predict the material behavior under different load histories, as well as rates of non-proportional hardening and ratcheting. The experiments and simulations confirmed both the suitability of the developed MTT, as well as the simulator of incremental plasticity implemented, based on non-linear models of Jiang-Sehitoglu and Tanaka.
APA, Harvard, Vancouver, ISO, and other styles
30

Durelli, Vinicius Humberto Serapilha. "Toward harnessing a Java high-level language virtual machine for supporting software testing." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/55/55134/tde-06012014-150025/.

Full text
Abstract:
High-level language virtual machines (HLL VMs) have been playing a key role as a mechanism for implementing programming languages. Languages that run on these execution environments have many advantages over languages that are compiled to native code. These advantages have led HLL VMs to gain broad acceptance in both academy and industry. However, much of the research in this area has been devoted to boosting the performance of these execution environments. Few eorts have attempted to introduce features that automate or facilitate some software engineering activities, including software testing. This research argues that HLL VMs provide a reasonable basis for building an integrated software testing environment. To this end, two software testing features that build on the characteristics of a Java virtual machine (JVM) were devised. The purpose of the rst feature is to automate weak mutation. Augmented with mutation support, the chosen JVM achieved speedups of as much as 95% in comparison to a strong mutation tool. To support the testing of concurrent programs, the second feature is concerned with enabling the deterministic re-execution of Java programs and exploration of new scheduling sequences<br>Máquinas virtuais de linguagens de programação têm desempenhado um papel importante como mecanismo para a implementação de linguagens de programação. Linguagens voltadas para esses ambientes de execução possuem várias vantagens em relação às linguagens compiladas. Essas vantagens fizeram com que tais ambientes de execução se tornassem amplamente utilizados pela indústria e academia. Entretanto, a maioria dos estudos nessa area têm se dedicado a aprimorar o desempenho desses ambientes de execução e poucos têm enfocado o desenvolvimento de funcionalidades que automatizem ou facilitem a condução de atividades de engenharia de software, incluindo atividades de teste de software. Este trabalho apresenta indícios de que máquinas virtuais de linguagens de programação podem apoiar a criação de ambientes de teste de software integrado. Para tal, duas funcionalidades que tiram proveito das características de uma máquina virtual Java foram desenvolvidas. O propósito da primeira funcionalidade e automatizar a condução de atividades de mutação fraca. Após a implementação de tal funcionalidade na máquina virtual Java selecionada, observou-se um desempenho até 95% melhor em relação a uma ferramenta de mutação forte. Afim de apoiar o teste de programas concorrentes, a segunda funcionalidade permite reexecutá-los de forma determinística além de automatizar a exploração de que novas sequências de escalonamento
APA, Harvard, Vancouver, ISO, and other styles
31

Hoole, Martin Philip Hereford. "The design and Manufacture of an accelerated fatigue testing machine for coronary stents." Master's thesis, University of Cape Town, 2007. http://hdl.handle.net/11427/3248.

Full text
APA, Harvard, Vancouver, ISO, and other styles
32

Shanyour, Basim. "Testing and Security Considerations in Presence of Process Variations." OpenSIUC, 2020. https://opensiuc.lib.siu.edu/dissertations/1804.

Full text
Abstract:
Process variations is one of the most challenging phenomena in deep submicron. Delay fault testing becomes more complicated because gate delays are not fixed but instead, they are statistical quantities due to the variations in the transistor characteristics. On the other hand, testing for hardware Trojan is also challenging in the presence of process variations because it can easily mask the impact of the inserted Trojan. This work consists of two parts. In the first part, an approach to detect ultra-low-power no-payload Trojans by analyzing IDDT waveforms at each gate in the presence of process variations is presented. The approach uses a novel ATPG to insert a small number of current sensors to analyze the behavior of individual gates at the IDDT waveform. The second part focuses on identifying a test set that maximizes the defect coverage for path delay fault. The proposed approach utilizes Monte-Carlo simulation efficiently and uses a machine-learning algorithm to select a small test set with high detect coverage.
APA, Harvard, Vancouver, ISO, and other styles
33

Su, Chuang. "Integrated Experimental Methods and Machine Learning for Tire Wear Prediction." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/99929.

Full text
Abstract:
A major challenge in tire research, is tire wear modeling. There are too many factors affecting tire wear, and part of those factors are difficult to be accurately expressed in physics and math. The objective of this research is to develop a machine learning based rubber sample wear model, and find the correlation between sample wear and tire wear. To develop this model, accurate and diverse wear data is necessary. The Dynamic Friction Tester (DFT) was designed and built for this purpose. This test machine has made it possible to collect accurate rubber sample wear data which has been validated under different conditions. Wear tests under diverse test conditions were conducted, and the test data were used to train machine learned based wear models with different algorithms, such as Neural Networks and Support Vector Machines. With test-proved wear behavior classification as additional input, and feature selection, performance of the trained rubber sample wear model has been further improved. To correlate rubber sample wear and tire wear, a set of correlation functions were developed and proposed. By validating the correlation functions using tire wear test data collected on roads, this research contributes a fast and economical approach to predict tire wear.<br>Doctor of Philosophy
APA, Harvard, Vancouver, ISO, and other styles
34

Niu, Fei. "Learning-based Software Testing using Symbolic Constraint Solving Methods." Licentiate thesis, KTH, Teoretisk datalogi, TCS, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-41932.

Full text
Abstract:
Software testing remains one of the most important but expensive approaches to ensure high-quality software today. In order to reduce the cost of testing, over the last several decades, various techniques such as formal verification and inductive learning have been used for test automation in previous research. In this thesis, we present a specification-based black-box testing approach, learning-based testing (LBT), which is suitable for a wide range of systems, e.g. procedural and reactive systems. In the LBT architecture, given the requirement specification of a system under test (SUT), a large number of high-quality test cases can be iteratively generated, executed and evaluated by means of combining inductive learning with constraint solving. We apply LBT to two types of systems, namely procedural and reactive systems. We specify a procedural system in Hoare logic and model it as a set of piecewise polynomials that can be locally and incrementally inferred. To automate test case generation (TCG), we use a quantifier elimination method, the Hoon-Collins cylindric algebraic decomposition (CAD), which is applied on only one local model (a bounded polynomial) at a time. On the other hand, a reactive system is specified in temporal logic formulas, and modeled as an extended Mealy automaton over abstract data types (EMA) that can be incrementally learned as a complete term rewriting system (TRS) using the congruence generator extension (CGE) algorithm. We consider TCG for a reactive system as a bounded model checking problem, which can be further reformulated into a disunification problem and solved by narrowing. The performance of the LBT frameworks is empirically evaluated against random testing for both procedural and reactive systems (executable models and programs). The results show that LBT is significantly more efficient than random testing in fault detection, i.e. less test cases and potentially less time are required than for random testing.<br>QC 20111012
APA, Harvard, Vancouver, ISO, and other styles
35

Johnson, Jay Tillay. "Defect and thickness inspection system for cast thin films using machine vision and full-field transmission densitometry." Thesis, Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/37234.

Full text
Abstract:
Quick mass production of homogeneous thin film material is required in paper, plastic, fabric, and thin film industries. Due to the high feed rates and small thicknesses, machine vision and other nondestructive evaluation techniques are used to ensure consistent, defect-free material by continuously assessing post-production quality. One of the fastest growing inspection areas is for 0.5-500 micrometer thick thin films, which are used for semiconductor wafers, amorphous photovoltaics, optical films, plastics, and organic and inorganic membranes. As a demonstration application, a prototype roll-feed imaging system has been designed to inspect high-temperature polymer electrolyte membrane (PEM), used for fuel cells, after being die cast onto a moving transparent substrate. The inspection system continuously detects thin film defects and classifies them with a neural network into categories of holes, bubbles, thinning, and gels, with a 1.2% false alarm rate, 7.1% escape rate, and classification accuracy of 96.1%. In slot die casting processes, defect types are indicative of a misbalance in the mass flow rate and web speed; so, based on the classified defects, the inspection system informs the operator of corrective adjustments to these manufacturing parameters. Thickness uniformity is also critical to membrane functionality, so a real-time, full-field transmission densitometer has been created to measure the bi-directional thickness profile of the semi-transparent PEM between 25-400 micrometers. The local thickness of the 75 mm x 100 mm imaged area is determined by converting the optical density of the sample to thickness with the Beer-Lambert law. The PEM extinction coefficient is determined to be 1.4 D/mm and the average thickness error is found to be 4.7%. Finally, the defect inspection and thickness profilometry systems are compiled into a specially-designed graphical user interface for intuitive real-time operation and visualization.
APA, Harvard, Vancouver, ISO, and other styles
36

Simons, A. J. H., and Raluca Lefticaru. "A verified and optimized Stream X-Machine testing method, with application to cloud service certification." Wiley, 2019. http://hdl.handle.net/10454/17608.

Full text
Abstract:
Yes<br>The Stream X-Machine (SXM) testing method provides strong and repeatable guarantees of functional correctness, up to a specification. These qualities make the method attractive for software certification, especially in the domain of brokered cloud services, where arbitrage seeks to substitute functionally equivalent services from alternative providers. However, practical obstacles include: the difficulty in providing a correct specification, the translation of abstract paths into feasible concrete tests, and the large size of generated test suites. We describe a novel SXM verification and testing method, which automatically checks specifications for completeness and determinism, prior to generating complete test suites with full grounding information. Three optimisation steps achieve up to a ten-fold reduction in the size of the test suite, removing infeasible and redundant tests. The method is backed by a set of tools to validate and verify the SXM specification, generate technology-agnostic test suites and ground these in SOAP, REST or rich-client service implementations. The method was initially validated using seven specifications, three cloud platforms and five grounding strategies.<br>European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement no. 328392, the Broker@Cloud project [11].
APA, Harvard, Vancouver, ISO, and other styles
37

Rau, Steffen Wolfgang. "Development and testing of a machine-coatable chitosan coating applied to a flexible packaging sealant." Connect to this title online, 2009. http://etd.lib.clemson.edu/documents/1252937299/.

Full text
APA, Harvard, Vancouver, ISO, and other styles
38

Abdulai, Abubakar-Sadiq Bouda. "Predicting Intraday Financial Market Dynamics Using Takens' Vectors; Incorporating Causality Testing and Machine Learning Techniques." Digital Commons @ East Tennessee State University, 2015. https://dc.etsu.edu/etd/2582.

Full text
Abstract:
Traditional approaches to predicting financial market dynamics tend to be linear and stationary, whereas financial time series data is increasingly nonlinear and non-stationary. Lately, advances in dynamical systems theory have enabled the extraction of complex dynamics from time series data. These developments include theory of time delay embedding and phase space reconstruction of dynamical systems from a scalar time series. In this thesis, a time delay embedding approach for predicting intraday stock or stock index movement is developed. The approach combines methods of nonlinear time series analysis with those of causality testing, theory of dynamical systems and machine learning (artificial neural networks). The approach is then applied to the Standard and Poors Index, and the results from our method are compared to traditional methods applied to the same data set.
APA, Harvard, Vancouver, ISO, and other styles
39

Sprunt, Alexander D. (Alexander Dalziel) 1977. "A machine for tribological experimentation on indexing continuous media with specific application to semiconductor testing." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/8555.

Full text
Abstract:
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2001.<br>Includes bibliographical references (p. 103).<br>Technology was developed to facilitate electrical contact tribology experiments on continuous media, dramatically reducing the difficulty of employing virgin material for each test. Specifically, a tester was designed to accurately reproduce semiconductor contactor operating environments while measuring contact resistance in-situ, thereby effecting the study of operating temperature, test current, cleaning method, and cleaning interval on contactor life. To manipulate the continuous media while preserving exact constraint, novel web handling machine elements were devised. Universal joints and beam type flexible couplings were employed for gimballing and castering axes, both at standard caster radii and at roller center. A kinematic edge constraint was designed. The torque transmission properties of clamped connections were alloyed to the favorable kinematics of typical pinned type connections by compliantly mounting a spherical roller bearing as a pinch roller.<br>by Alexander D. Sprunt.<br>S.M.
APA, Harvard, Vancouver, ISO, and other styles
40

Nyman, Mathias, and Susanna Johansson. "Fatigue testing machine : To simulate daily use on multi-directional impact protection systems in helmets." Thesis, KTH, Hållbar produktionsutveckling (ML), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-300121.

Full text
Abstract:
During the development process of a product, tests are typically conducted to ensure the quality of the features of the product before it is made available to the public. The scope of this project was to find a realistic and reliable way to test components in a Multi-Directional Impact Protection System (MIPS) in fully mounted helmets. The reason for this type of testing is to ensure that all components included in the Brain Protection System (BPS) hold up over time in daily use. Therefore, the goal with this project was to design and build a new test machine that could simulate the long-term effects of material fatigue on the MIPS BPS. The machine was able to shake a head with a helmet attached to it to simulate the lifecycle use of a helmet in a shorter time span. The motion of the machine was powered by a stepper motor who is connected to a rocker arm, that transfers a rotational motion to a linear motion, heaving a plate with the head attached to it. The motor is controlled by an Arduino which receives signals from a control panel that enables adjustments to the number of cycles that the machine runs. This report describes the main components, design and function of the machine.<br>Under produktutvecklingsprocesser genomförs tester för att säkerställa produktens olika kvaliteter innan den görs tillgänglig för allmänheten. Syftet med detta projekt var att hitta ett realistiskt och pålitligt sätt att testa komponenter i ett MIPS (Multi-Directional Impact Protection System) i fullt monterade hjälmar. Anledningen till denna typ av testning är att säkerställa att alla komponenter som ingår i Brain Protection System (BPS) håller över tid vid daglig användning. Målet var därför att skapa en ny testmaskin för att simulera de långsiktiga effekterna av förslitning på komponenterna i MIPS BPS. Maskinen kan skaka ett huvud med en hjälm fäst på för att simulera användningen under en hel livscykel hos en hjälm. Maskinen drivs av en stegmotor som är ansluten till en vipparm, vilken i sin tur överför rotationsrörelsen till en linjär rörelse som lyfter plattan med huvudet. Motorn styrs av en Arduino som tar emot signaler från kontrollpanelen vilket möjliggör justeringar av antalet cykler som maskinen kör. Denna rapport redogör för maskinens huvudsakliga komponenter, konstruktion och funktion.
APA, Harvard, Vancouver, ISO, and other styles
41

Wang, Kuan-Chun, and 王冠君. "Implementation of Torque Testing Machine." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/67658009679749297841.

Full text
Abstract:
碩士<br>國立彰化師範大學<br>電機工程學系<br>100<br>The study of the torque testing machine is used to measure the output torque of rotary device, for example, gear reducer motors, induction motors, servo motors, DC motors, etc. Most of the torque measuring equipments use the torque transducer as a detection device. Although its structure is simple and easy to install, the purchasing cost is expensive. This thesis applied load cell as a torque detection device. The weight on the load cell is measured while gear reducer motors drive mechanical spinning arm. And the correlation between the length of spinning arm and the weight on load cell is therefore converted as output torque value to measure the output torque of spinning devices. The electric control device, comprised of programmable logic controller (PLC), human-machine interface (HMI) and digital multi power meter, drives the loading of pneumatic brakes and simulate mechanic to measure the torque in a range of 5~84kgf-m. Also, the torque output of a running gear reducer and motor electrical features can be measured, recorded and collected automatically during operating. Since manual recording is not required, the cost of testing device and manpower can be drastically decreased. Therefore, the cost of torque detector effectively reduces 35.2%.
APA, Harvard, Vancouver, ISO, and other styles
42

Chang, Mao Chan, and 張茂展. "LED Automatic Testing Packing Machine." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/26j259.

Full text
Abstract:
碩士<br>國立虎尾科技大學<br>光電與材料科技研究所<br>98<br>Social science and technology changes with each passing day now, people&apos;&apos;s environmental consciousness resumes, incandescent lamp bulbs or fluorescent lamps used are managed at present, because give out light although efficiency is good, but the power consumption is very large, so is unable to fit on the mobile phone or liquid crystal television (display) It is in a poor light to regard as the TV, machine mobile phone, note type screen of the computer inside, the present backlight source uses the cold cathode to be in charge of (CCFL) ,But the cold cathode is in charge of injuring to the environment very influences the hard iron, so begin to utilize LED to begin to be regarded as liquid crystal display, mobile phone, note type computer Wait for the backlight source of articles, certainly begin to have the so-called lighting intelligently too, but it has been open and upright and brilliant after encapsulating and finishing all the time from the upper reaches that this some devices must all use a large amount of LED, LED, need to test LED luminance and wavelength, and classification, then start and test according to LED after classifying, test get the last one make Cheng finish, &apos;&apos; pack &apos;&apos;, need go on the next procedure for the customer pack, but the one that influenced and can produce until whole production is &apos;&apos; test (Testing) &apos;&apos; and &apos;&apos; the packaging (Packing) &apos;&apos;,it examine LED have for products bad been trouble or degree is for exclusion that we need wavelength, the packaging seals LED and is put into year while taking, seal and stand up jointly, certainly each LED direction needs to be the same, but part this design, can influence how that improve test and pace, good rate pack, pace pack, will carry on LED and pack the most important subject while testing. But in this technological report, want, test disc we design newly type test packer and a large amount of circulate turn, test packer produce, can have, have difference while being tower on the market at present mainly, if we are nticipated fast whether the disc type apparatus can produce the result.
APA, Harvard, Vancouver, ISO, and other styles
43

Kuo-Sheng, Yang, and 楊國聖. "DSP Based Electrohydraulic Material Testing Machine." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/82855212561937612329.

Full text
Abstract:
碩士<br>國立臺灣科技大學<br>機械工程系<br>87<br>Electrohydraulic control system has been broadly adopted in many low frequency applications. Due to the limitation of sampling rate of PC-based digital control system, an electrohydraulic material testing machine is difficult to achieve high frequency testing. In this thesis, a personal computer associated with a digital signal processor is proposed to accomplish the real-time force and position controls. Since the controller of an electrohydraulic material testing machine must be designed to adaptive for various operating conditions. Here, self-organizing fuzzy control and optimal proportional control are implemented. Self-organizing fuzzy control basically includes a conventional fuzzy controller and a learning mechanism to modify fuzzy rules. In addition, the control program is developed in a DSP based personal computer, which can tremendously improve the sampling rate to widen the testing frequency range.
APA, Harvard, Vancouver, ISO, and other styles
44

Vilaça, Diogo Filipe Silva. "Bidirectional finite state machine based testing." Master's thesis, 2018. http://hdl.handle.net/1822/64258.

Full text
Abstract:
Dissertação de mestrado em Computer Science<br>This thesis aims to develop a new methodology that combines model-based testing and bidirectional transformations. More precisely, the method of software testing used is blackbox testing, where the system under test is a black-box. Without knowledge of the blackbox’s internal structures or implementation, the focus is on the inputs and outputs. To infer a model for this black-box, machine learning algorithms are used by submitting test cases against the black-box and observing the correspondent output. The resulting model is a finite state machine that produces the same outputs of the black-box when submitted the same inputs used in its making. Usually, in this approach, new test cases are provided to infer better models. In this thesis, bidirectional techniques will be studied in order to guarantee the conformity between both the model and the instance evolution. This way, it is allowed not only the evolution of the test cases and co-evolution of the model, but also the evolution of the model and the co-evolution of the test cases.<br>Esta tese visa desenvolver uma nova metodologia que combina Model-Based Testing (MBT) e Bidirectional Transformations (Bx). Mais precisamente, o método de teste de software usado é Black-Box Testing (BBT), onde o System Under Test (SUT) é uma black-box. Sem o conhecimento das estruturas internas da black-box ou da sua implementação, o foco está nos inputs e outputs. Para inferir um modelo para esta black-box, são usados algoritmos de aprendizagem através de interrogações à black-box (i.e., casos de teste) e da observação do output correspondente. O modelo resultante é uma Finite State Machine (FSM), que produz os mesmos outputs da black-box, quando lhe são submetidos os mesmos inputs usados na sua criação. Geralmente, nesta abordagem, novos casos de teste são fornecidos para inferir melhores modelos. Nesta tese, serão estudadas técnicas bidireccionais com o objetivo de garantir a conformidade entre as evoluções do modelo e dos casos de teste. Desta forma, é permitida não só a evolução dos casos de teste e co-evolução do modelo, mas também a evolução do modelo e a co-evolução dos casos de teste.
APA, Harvard, Vancouver, ISO, and other styles
45

Janeira, Manuel Maria Machado de Brito Araújo. "Thermal chamber for adhesives creep testing machine." Dissertação, 2020. https://hdl.handle.net/10216/126827.

Full text
APA, Harvard, Vancouver, ISO, and other styles
46

Chen, Ying-chen, and 陳映辰. "A vision based electrohydraulic fatigue testing machine." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/14225024624578269049.

Full text
Abstract:
碩士<br>國立臺灣科技大學<br>機械工程系<br>98<br>The application of vision based system will be limited by the sampling rate of image processes which is often lower than the conventional sensors. In the high frequency fatigue test, the trajectory tracking approach is the main reason resulting in bad control performance. In this thesis, it will develop suitable controllers for implementations of vision based electro-hydraulic fatigue testing machine. In experiments, Self-Organizing Sliding Mode Fuzzy Control is developed to carry out dynamic tracking control and self-tuning PID is used to control the average value and the maximum value of amplitude, respectively. The variety frequency fatigue testing results indicate the control performance and precision between the different controllers, and then it will discuss the feasibility of non-contacted CCD camera to replace contacted sensors.
APA, Harvard, Vancouver, ISO, and other styles
47

Chang, Yu Jen, and 張又仁. "Predicting rutting potential using gyrataroy testing machine." Thesis, 1994. http://ndltd.ncl.edu.tw/handle/54839635880103933720.

Full text
APA, Harvard, Vancouver, ISO, and other styles
48

Janeira, Manuel Maria Machado de Brito Araújo. "Thermal chamber for adhesives creep testing machine." Master's thesis, 2020. https://hdl.handle.net/10216/126827.

Full text
APA, Harvard, Vancouver, ISO, and other styles
49

Chang, Yen-tsung, and 張晏聰. "Vision Based Single-Axial Pneumatic Fatigue Testing Machine." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/95756106040761239834.

Full text
Abstract:
碩士<br>國立臺灣科技大學<br>機械工程系<br>99<br>The pneumatic fatigue testing machine for badminton rackets is generally set up by limit switches and pneumatic on/off values. Its position control performance needs to be improved. This thesis proposes a vision-based pneumatic servo control system to improve the badminton rackets fatigue testing performance. CCD camera is a non-contacted displacement. To associate with the Self-organizing sliding mode fuzzy controller (SOSMFC), it can be implemented for low frequency fatigue testing. Experimental results indicates that SOSMFC is feasible for various commends and frequencies, and provides excellent control performance. And it will discuss the feasibility of vision based single-axial pneumatic fatigue testing machine.
APA, Harvard, Vancouver, ISO, and other styles
50

Yeh, Chieh-Yuan, and 葉介元. "Design and Testing of the Electrolytic Polishing Machine." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/39249136540448844187.

Full text
Abstract:
碩士<br>逢甲大學<br>紡織工程所<br>94<br>The electrolytic polishing is operated in the specific electrolyte bath with appropriate direct current source on the both sides of electrodes to generate the electrolytic effect and polish the surface roughness of workpiece. In the electrolyte bath, the micro-protrusion part of workpiece can be removed and polished due to the electron discharge of electric field so as to decrease the roughness of workpiece. The aim of this study is to design an electrolytic polishing machine and prove the performance of it. The test was proceeded with a 316L stainless steel as workpiece and discussed the impact factors of electrolytic concentration, rotational speed of the electrode and electrolytic time on the roughness and light reflection of it. It is proved that the operated conditions for an optimal roughness of workpiece are as follows: the electrolytic concentration is 30 wt%, the rotational speed of the electrode is 350 r.p.m, and electrolytic time is 30 minutes under the constant electric current of 0.95 A.
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography