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Chander, Karthik Balachandran. "Adaptive tool selection strategies for drilling in flexible manufacturing systems." Thesis, Texas A&M University, 2004. http://hdl.handle.net/1969.1/566.
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The thesis presents an approach to adaptive decision making strategies to reduce bottlenecks in a drilling operation and to extend tool life. It is an attempt to portray the real drilling system in a typical Flexible Manufacturing System (FMS) layout. The system designed serves as back end intelligence to drilling machines (INTELLIDRILL) in a Flexible Manufacturing System for making dynamic and real time decisions. INTELLIDRILL uses mathematical and adaptive tool reliability models to simulate the machining conditions and tool availability for an operation based on history of tool failures. The results are used to compute the machining parameters and the tools required for an operation. INTELLIDRILL can devise strategies for different tool materials to operate on batches of different materials. INTELLIDRILL decisions could lead to significant savings in tooling costs and reduction in flow line bottlenecks.
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Kilinc, Fatma. "The Tool Transporter Movements Problem In Flexible Manufacturing Systems." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606017/index.pdf.
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In this study, we address job sequencing and tool switching problem arising in Flexible Manufacturing Systems. We consider a single machine with limited tool slots on its tool magazine. The available tool slots cannot accommodate all the tools required by all jobs, therefore tool switches between jobs are required. A single tool transporter with limited capacity is used in transporting the tools from the storage area to the machine. Our aim is to minimize the number of tool transporter movements.
We provide two mixed integer linear programming formulations of the problem, one of which is based on the traveling salesman problem. We develop a Branch-and-Bound algorithm powered with various lower and upper bounding techniques for optimal results. In order to obtain good solutions in reasonable times, we propose Beam Search algorithms.
Our computational results reveal the satisfactory performance of the B&B algorithm for moderate sized problems. Moreover, Beam Search techniques perform well for large-sized problems.
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Ozbayrak, M. "Design of tool management systems for flexible manufacturing systems." Thesis, Loughborough University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359905.
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De, Souza Robert B. R. "The management of tool flow in highly automated batch manufacturing systems." Thesis, Loughborough University, 1988. https://dspace.lboro.ac.uk/2134/28059.
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An overall framework to provide a complete tool management solution to an existing or specified manufacturing system is constructed, and prototype software provided, for a hierarchy of levels of tool flow automation. The work is targeted at the design and operation of tooling systems for prismatic parts flexible machining systems ranging from stand-alone unmanned machining stations to highly automated multi-machine multi-cell configurations. The research work moves from identification and category definition of a tool flow network appropriate for the manufacturing requirements, through the careful selection and definition of operating rules and strategies to the evaluation of the options available for tool issue and assignment. Two main computer aids (design facilities) to provide support in a systems thinking approach to tool flow management have been developed and tested with the aid of case studies. The essential role of these design facilities is the timely scheduling of tools to satisfy a short to medium term manufacturing task, and to examine the cost and number of captive tools under selected rules and strategies.
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Liu, Yang. "A flexible distributed design assistance tool in early design phases." Thesis, Stellenbosch : Stellenbosch University, 2007. http://hdl.handle.net/10019.1/21438.
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Dissertation (PhD)--University of Stellenbosch, 2007.ENGLISH ABSTRACT: The globalisation is increasing the complexity of product development in terms of product variants and the range of technologies implemented. It emphasises the requirement for developing various design information support systems for the world market. However, small and medium enterprises that employ a wide range of design procedures may not be able to afford customised information support systems, with the result that there is a need for flexible, i.e. easily adaptable, design support tools. Four case studies were carried out to investigate the requirements for an information support system aimed at the design process and design documents. They indicated that a design information support system aimed at supporting design teams in the pre-detail mechanical design phases should be able to adapt various design methods and handle design information in a flexible way. Flexible here means being applicable over a wide range of contexts and extendable without affecting data already captured. Ontology based approaches are widely applied where diverse information has to be handled. The development of the Internet today also makes a distributed design approach more and more popular for mechanical design. An internet-based design support system called DiDeas II (Distributed Design assistant) was developed here with an ontologybased approach implemented to provide distributed and flexible assistance during concept generation in small companies. The DiDeas II has separate server side and client side programs, which communicate through a TCP/IP connection. DiDeas II allows design teams to manage their design information according to various design methods, to decrease time-delays and to improve communication between team members. These benefits were confirmed in two case studies carried out to evaluate DiDeas II. Keywords: Distributed design; ontology; concept design, web-based system.
AFRIKAANSE OPSOMMING: Globalisering verhoog die kompleksiteit van produkontwikkeling, in terme van produk variante en die bereik van tegnologieë wat geïmplementeer word. Dit beklemtoon die behoefte om verskeie ontwerp-inligting-ondersteuningstelsels vir die wêreldmark te ontwikkel. Klein en medium ondernemings wat 'n wye spektrum ontwerpsprosedures gebruik, kan egter nie doelgemaakte inligting-ondersteuningstelsels bekostig nie, met die gevolg dat daar 'n behoefte vir maklik-aanpasbare ontwerp ondersteuningstelsels is. Vier gevallestudies is uitgevoer om die vereistes vir 'n inligting-ondersteuningstelsel gemik op die ontwerpproses en ontwerp dokumente, te ondersoek. Dit het aangetoon dat 'n ontwerp-inligting-ondersteuningstelsel, wat ontwerpspanne in die voor-detail meganiese ontwerp fases moet ondersteun, by verskeie ontwerpmetodes moet kan aanpas en ontwerpsinligting op 'n aanpasbare manier kan hanteer. Aanpasbaarheid in hierdie konteks beteken toepaslik oor 'n wye spektrum kontekste en uitbreibaar sonder om data wat alreeds ingevoer is, te beïnvloed. Ontologie-gebaseerde benaderings word wyd toegepas waar diverse inligting hanteer moet word. Die ontwikkeling van die Internet maak 'n verspreide-ontwerpbenadering meer en meer gewild vir meganiese ontwerp. 'n Internet-gebaseerde ontwerpondersteuningstelstel genaamd DiDeas II (Distributed Design assistant) is hier ontwikkel met 'n ontologie-gebaseerde benadering wat daarop gemik is om verspreide, aanpasbare hulp te verleen aan klein maatskappye gedurende konsep- ontwikkeling. Die DiDeas II stelsel het afsonderlike bediener en kliënt programme wat deur 'n TCP/IP verbinding kommunikeer. DiDeas II laat ontwerpspanne toe om hulle ontwerp inligting volgens verskeie ontwerpmetodes te bestuur, tydvertragings te verminder en om kommunikasie tussen spanlede te verbeter. Hierdie voordele is bevestig in twee gevallestudies wat uitgevoer is om DiDeas II te evalueer. Sleutelwoorde: Verspreide ontwerp; ontologie; konsepontwerp; web-gebaseerde stelsel.
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Kilic, Zekai Murat. "Generalized modelling of flexible machining system with arbitrary tool geometry." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/52808.
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The final shape of mechanical parts is mainly determined through turning, boring, drilling and milling operations. The prediction of the cutting forces, torque, and power of the machining process, and surface errors and vibration marks left on the parts is required to plan the machining operations and achieve shorter production cycle times while avoiding damage on the part, tool and machine. Past research has focused on developing dedicated mathematical models for each machining operation and tool type. However, the tool geometry and configuration of the machining set-up varies widely depending on the part geometry and application. This thesis presents a generalized mathematical model of machining operations carried out using geometrically defined cutting edges.
The mechanics of cutting between the tool edge and the work material are modelled to predict the friction and normal forces on the rake face of a single cutting edge. The combined static and dynamic chip thickness is modelled as a function of tool geometry, the kinematics of machining operation and the relative regenerative vibrations between the tool and workpiece. The cutting forces are transformed to process coordinates by considering the orientation of cutting edge and the kinematics of the machining operation, and are applied on the structural dynamics of the machine tool and workpiece by distribution along the cutting tool–workpiece contact zone.
The cutting forces, vibrations, chatter stability and surface errors are simultaneously predicted in a semi-discrete time domain.
The geometry and force transformation models are unified in a parametric, mathematical model which covers all cutting operations. The application of the proposed model is demonstrated on turning, drilling and milling operations; multifunctional tools that combine drilling-boring and chamfering in one operation; and two parallel face-milling cutters machining a plate from both sides. The proposed mathematical models are experimentally validated by comparing the measured forces, surface errors, vibrations and chatter stability charts against simulations.
The thesis shows the first unified, generalized mathematical modelling of metal cutting operations in the literature. The proposed model is expected to widen the application of science-based machining process simulation, planning and optimization methods in the virtual production of parts.Applied Science, Faculty of
Mechanical Engineering, Department of
Graduate
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Zhang, Pan. "Tool flow management in batch manufacturing systems for cylindrical components." Thesis, Loughborough University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307912.
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Graver, Thomas William. "Determination of cutting-tool inventory levels in a flexible manufacturing system." Thesis, Georgia Institute of Technology, 1987. http://hdl.handle.net/1853/30775.
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Xiang, Danhua. "Designing a Flexible Software Tool for RBF Approximations Applied to PDEs." Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-133631.
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This paper aims at addressing how to design a flexible software for RBF-based numerical solution of partial differential equations (PDEs). In the process, object-oriented analysis and design (OOAD) approach combined with feature modeling, is adopted to construct object models of PDE solvers. This project was mplemented in Fortran 90, emulating object oriented constructs by encapsulating particular data structures and subroutines in modules to represent classes. The separation of mathematical domains and numerical domains as well as the introduction of the workflow manager and operations gives a significant flexibility and extendability for the software. For illustration, a solver for Dam seepage problem is constructed with the new design, compared with the one by the pre-existing reference code.
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Davis, Tyler A. "Flexible machine tool control for direct, in-process dimensional part inspection /." Diss., CLICK HERE for online access, 2004. http://contentdm.lib.byu.edu/ETD/image/etd478.pdf.
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Davis, Tyler Addison. "Flexible machine tool control for direct, in-process dimensional part inspection." BYU ScholarsArchive, 2004. https://scholarsarchive.byu.edu/etd/139.
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For some time now coordinate measuring machines have been an integral part of the shop floor. The goal has been to make coordinate measuring machines (CMMs) into tools that can easily be used by machinists to improve their manufacturing capabilities. The value of a CMM as a quality control tool is undisputed. Now efforts are being made to further reduce the time and cost of measurement by reducing the physical distance between machining and measuring processes. The ability to reduce that distance to zero and measure a part directly on the chip-making machine has been a goal for many years. Dimensional inspection of parts is primarily conducted by coordinate measuring machines operating on motion instructions from task planning software. The research in direct machining and control (DMAC) at BYU has identified a potential application of CMM technologies on existing machine tools. To prove that a machine tool can be controlled as a CMM with the DMAC controller, this research will integrate the software package PC-DMIS provided by Wilcox Associates, Inc. with a DMAC controller provided by Direct Controls, Inc. to conduct in-process dimensional inspection of parts as they are being machined. This process is referred to as DirectCMM because it will link the DMAC controller directly to PC-DMIS without need for post-processing. This thesis will lay the groundwork for future efforts at developing systems that utilize in-process part inspection to dynamically correct computer aided manufacturing (CAM) process plans. To aid future efforts at dynamic CAM process updating, a software interface specification will be created for passing measurement data between CMM and CAD/CAM software packages. A CMM control specification will also be created to provide a standard method for controlling coordinate measuring machines with the DMAC controller. Possible methods for dynamic CAD/CAM updating will be explored.
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Mohammadkhani, Ali. "Modified colloidal lithography : a flexible tool for fabrication of periodic nanostructures." Thesis, University of Birmingham, 2013. http://etheses.bham.ac.uk//id/eprint/4408/.
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This PhD project sets out to investigate the potential of colloidal lithography and explore its application for the creation of highly accurate periodic nanostructures. This research can be classified into three main sections based on the materials used in fabrication. In the first section, fabrication of high precision nanopatterns on a photoresist surface was studied using the inherent potential of polystyrene spheres as lenses. The experiments were conducted to obtain uniform arrays of single and dual nanoholes on a surface of AZ 5214-E photoresist via monolayer and bilayer colloidal lithography, respectively. In the second section, the research intention was to produce uniform arrays of nanostructures by using colloidal lithography, soft lithography and metal deposition. In this section, two different strategies were proposed. The first strategy was mainly devoted to fabricated ordered arrays of periodic nanostructures on the basis of PDMS/PDMS replica moulding. In the third section, nickel electroforming was developed to produce periodic nanostructures through a highly accurate approach. The proposed nanofabrication methods within this research facilitate production of multi-material periodic nanostructures with a high precision and tuneable size.
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Kolahan, Farhad. "The effect of tool sharing on reliability of flexible manufacturing systems." Thesis, University of Ottawa (Canada), 1993. http://hdl.handle.net/10393/6836.
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A major consideration in opting for reliability and flexibility in Flexible Manufacturing Systems (FMSs) is to enhance the availability of resources in order to maintain an uninterrupted production. This means that sufficient redundancies must be foreseen at the preliminary production planning stage to cope with the random breakdowns of components. In this research effort four mathematical models were developed to determine the spare requirements for tooling system in FMSs, so that a desired system reliability is achieved with minimum cost and/or tool slots occupancy of the system. For the first time, the influences of tool sharing on cost, reliability, spares requirement, and tool magazines capacity of FMSs, in which tools and tool transporter are subject to general failure distributions, were analyzed. The developed models have been applied to a hypothetical example and the computational results were compared, for the case where tool sharing is not applicable and where tool sharing can be implemented. Several sets of sensitivity analysis were also performed on different system parameters through which the effects of the number of tools shared among machines, the required system reliability, and operating times for tools on the system reliability and cost were assessed.
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Krajeski, Aaron. "A flexible tool for the visualization and manipulation of musical mapping networks." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=121551.
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Most digital musical instruments (DMIs) gather gestural input from musicians by way of electronic sensors and transform these data into sound through separate synthesis engines. The mapping of control inputs to synthesis parameters is arbitrary, multi-faceted and extremely important for the effectiveness of DMIs. Software tools exist to aid in this process and attempt to render the task of musical mapping more transparent, swift and configurable. This thesis presents MapperGUI, a cross-platform graphical tool for the manipulation of musical mapping networks. The libmapper software library, developed at the Input Devices and Music Interaction Laboratory, creates a standard framework for DMIs to communicate data on a distributed network and map their signals collaboratively in real-time. MapperGUI presents a graphical user interface for libmapper networks, allowing non-expert users to manipulate the text-based system. The interface aims to be flexible, such that it can accommodate the vast array of musical networks and tasks that must be performed when mapping. To this end, it provides multiple independent visualizations and interaction modes within a single framework. This document explores some of the issues challenging the field of musical mapping and describes the motivations behind the MapperGUI project in this context. Relevant research in the fields of data visualization and interface design is summarized and applied to the task of creating a graphical user interface for libmapper networks. Prior graphical interfaces for libmapper are examined for successful features that can be incorporated into MapperGUI. Specific implementation challenges and features of the final program are described. Insight gained from interviews with users of MapperGUI is presented, along with future work and possible extensions for the interface.MapperGUI is available for free download as a standalone application at www.libmapper.org/downloads. All code is open-source and can be accessed at https://github.com/mysteryDate/webmapper.La plupart des instruments de musique numériques (IMN) assemble les données gestuelles des musiciens par des capteurs électroniques et transforme ces données en son à travers de programmes de synthèse séparés. Le mappage d'entrées de commandes aux paramètres de synthèse est arbitraire, à multiples facettes et extrêmement important pour l'efficacité des IMN. Les outils logiciels existent pour aider ce processus et tentent de rendre la tâche du mappage musical plus transparente, rapide et configurable. Cette thése présente MapperGUI, un outil graphique multiplateforme pour la manipulation des réseaux de mappage musicaux.La bibliothèque logiciel libmapper, développée au Input Devices and Music Interaction Laboratory, crée un cadre standard pour que les IMN communiquent les données sur un réseau réparti et map leurs signaux en collaboration en temps réel. MapperGUI présente une interface utilisateur pour les réseaux libmapper, ce qui permet aux utilisateurs non-experts de manipuler ce système textuel. L'interface a pour but d'être flexible, en sorte qu'elle puisse accommoder la vaste gamme de réseaux et de tâches musicales qui doivent être complétées en mappant. À cette fin, elle offre plusieurs visualisations et modes d'interactions indépendantes à l'intérieur d'un seul cadre. Ce document porte sur quelques un des enjeux qui affrontent le domaine du mappage musical et décrit les motivations qui sous-tendent le projet MapperGUI dans ce contexte. De la recherche pertinente dans les domaines de la visualisation des données et la conception d'interface sont résumées et appliquées à la tâche de créer une interface d'utilisateur graphique pour les réseaux de libmapper. Des interfaces graphiques précédentes pour libmapper sont examinées pour leurs caractéristiques réussies qui peuvent être incorporées à MapperGUI. Des difficultés de mise en oeuvre précises et des caractéristiques du programme final sont décrites. Les connaissances tirées d'entrevues avec des utilisateurs de MapperGUI sont présentées, ainsi que des travaux futurs et des extensions possibles pour l'interface.MapperGUI est disponible pour téléchargement gratuit en tant qu'application autonome à www.libmapper.org/downloads. Tout le code est code source libre et peut être accédé à https://github.com/mysteryDate/webmapper.
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Perera, D. T. S. "The production planning problems of flexible manufacturing systems with high tool variety." Thesis, University of Strathclyde, 1988. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=23762.
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This research is concerned with certain production planning problems associated with flexible manufacturing systems (FMS) with high tool variety. In this environment of FMS, the tool requirements at workstations exceed the respective tool magazine capacities. During an extensive survey of related literature, it appeared that the problems associated with this type of FMS have been overlooked by the FMS research community. The operational problems of FMS are discussed with special reference to the constraints imposed by tooling. The characteristics of the selected FMS type are clearly defined. This discussion is supplemented with a detailed description of a real FMS which resembles the operations of the selected type of FMS. Having identified certain drawbacks of some existing simulation software, the development of a comprehensive FMS simulator which uses a novel hybrid modelling technique is discussed. The use of a graphical post-processor which can be used to enhance the system logic of the FMS is also described number of parameters associated with the tool management system are identified and the methods are described to evaluate these parameters. The importance of evaluating these parameters in design and operation of an FMS is stressed. The development of a tool post-processor which can assist in identifying the scale of the tooling problem and in evaluating tool management parameters is presented. A variety of tool availability strategies which reduce the tool exchange rates are suggested and evaluated. Finally, the part selection (for immediate processing) problem is solved using a novel technique which takes the advantage of the availability of real time data in FMS.
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Haupt, Cornelis Dirk. "Mesoscale Brain Explorer, a flexible Python-based image analysis and visualization tool." Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/62667.
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Imaging of mesoscale brain activity is used to map interactions between brain regions. This work has benefited from the pioneering studies of Grinvald et al., who employed optical methods to image brain function by exploiting the properties of intrinsic optical signals and small molecule voltage-sensitive dyes. Mesoscale interareal brain imaging techniques have been advanced by cell targeted and selective recombinant indicators of neuronal activity. Spontaneous resting state activity is often collected during mesoscale imaging to provide the basis for mapping of connectivity relationships using correlation. However, the information content of mesoscale datasets is vast and is only superficially presented in manuscripts given the need to constrain measurements to a fixed set of frequencies, regions of interest, and other parameters. We describe a new open source tool written in python, termed mesoscale brain explorer (MBE), which provides an interface to process and explore these large datasets. The platform supports automated image processing pipelines with the ability to assess multiple trials and combine data from different animals. The tool provides functions for temporal filtering, averaging, and visualization of functional connectivity relations using time-dependent correlation. Here, we describe the tool and show applications, where previously published datasets were reanalyzed using MBE.Medicine, Faculty of
Graduate
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Chen, Jie. "Adaptive Scheduling and Tool Flow Control in Automated Manufacturing Systems." Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/27159.
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The recent manufacturing environment is characterized as having diverse products due to mass customization, short production lead-time, and unstable customer demand. Today, the need for flexibility, quick responsiveness, and robustness to system uncertainties in production scheduling decisions has increased significantly. In traditional job shops, tooling is usually assumed as a fixed resource. However, when tooling resource is shared among different machines, a greater product variety, routing flexibility with a smaller tool inventory can be realized. Such a strategy is usually enabled by an automatic tool changing mechanism and tool delivery system to reduce the time for tooling setup, hence allows parts to be processed in small batches. In this research, a dynamic scheduling problem under flexible tooling resource constraints is studied. An integrated approach is proposed to allow two levels of hierarchical, dynamic decision making for job scheduling and tool flow control in Automated Manufacturing Systems. It decomposes the overall problem into a series of static sub-problems for each scheduling window, handles random disruptions by updating job ready time, completion time, and machine status on a rolling horizon basis, and considers the machine availability explicitly in generating schedules.
Two types of manufacturing system models are used in simulation studies to test the effectiveness of the proposed dynamic scheduling approach. First, hypothetical models are generated using some generic shop flow structures (e.g. flexible flow shops, job shops, and single-stage systems) and configurations. They are tested to provide the empirical evidence about how well the proposed approach performs for the general automated manufacturing systems where parts have alternative routings. Second, a model based on a real industrial flexible manufacturing system was used to test the effectiveness of the proposed approach when machine types, part routing, tooling, and other production parameters closely mimic to the real flexible manufacturing operations. The study results show that the proposed scheduling approach significantly outperforms other dispatching heuristics, including Cost Over Time (COVERT), Apparent Tardiness Cost (ATC), and Bottleneck Dynamics (BD), on due-date related performance measures under both types of manufacturing systems models. It is also found that the performance difference between the proposed scheduling approach and other heuristics tend to become more significant when the number of machines is increased. The more operation steps a system has, the better the proposed method performs, relative to the other heuristics. This research also investigates in what conditions (e.g. the number of machines, the number of operation steps, and shop load conditions) the proposed approach works the best, and how the performance of this proposed approach changes when these conditions change.
When tooling resource is shared, parts can be routed to machines that do not have all the required tools. This may result in higher routing flexibility. However, research work to date in sharing of tooling resources often places more emphasis on the real-time control and manipulation of tools, and pays less attention to the loading of machines and initial tool allocation at the planning stage. In this research, a machine-loading model with shared tools is proposed to maximize routing flexibility while maintaining minimum resident tools. The performance of the proposed loading heuristic is compared to that of a random loading method using hypothetically generated single stage system models. The study result indicates that better system performances can be obtained by taking into account the resident tooling ratio in assigning part types and allocating tools to machines at the initial planning stage.Ph. D.
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White, Gregory William. "An investigation of the Australian layered elastic tool for flexible aircraft pavement thickness design." Queensland University of Technology, 2007. http://eprints.qut.edu.au/16663/.
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APSDS is a layered elastic tool for aircraft pavement thickness determination developed and distributed by Mincad Systems and based on the sister software Circly. As aircraft pavement thickness determination remains an empirical science, mechanistic-empirical design tools such as APSDS require calibration to full scale pavement performance, via the S77-1 curve. APSDS provides the unique advantage over other tools that it models all the aircraft in all their wandering positions, negating the need for designers to use pass to cover ratios and acknowledging that different aircraft have their wheels located at difference distances from the aircraft centerline. APSDS requires a range of input parameters to be entered, including subgrade modulus, aircraft types, masses and passes and a pavement structure. A pavement thickness is then returned which has 50% design reliability. Greater levels of reliability are obtained by conservative selection of input values. Whilst most input parameters have a linear influence on pavement thickness, subgrade modulus changes have a greater influence at lower values and less influence at higher values. When selecting input values, designers should concentrate their efforts on subgrade modulus and aircraft mass as these have the greatest influence on the required pavement thickness. Presumptive or standard values are generally acceptable for the less influential parameters. S77-1 pavement thicknesses are of a standard composition with only the subbase thickness varying. Non-standard pavement structures are determined using the principle of material equivalence and the FAA provides range of material equivalence factors, of which the mid-range values are most commonly used. APSDS allows direct modelling of non-standard pavement structures. By comparing different APSDS pavements of equal structural capacity, implied material equivalences can be calculated. These APSDS implied material equivalences lie at the lower end of the ranges published by FAA. In order to obtain consistence between APSDS and the FAA guidance, the following material equivalence values are recommended: * Asphalt for Crushed Rock. 1.3. * Crushed Rock for Uncrushed Gravel. 1.2. * Asphalt for Uncrushed Gravel. 1.6. Proof rolling regimes remain an important part of the design and construction of flexible aircraft pavements. Historically, designers relied on Bousinesq's equation and the assumption of point loads on semi-finite homogenous materials to determine proof rolling regimes using stress as the indicator of damage. The ability of APSDS to generate stress, strain and deflection at any depth and any location across the pavement allows these historical assumptions to be tested. As the design of a proof rolling regime is one of comparing damage indicators modelled under aircraft loads to those under heavy roller loads, the historical simplifications are generally valid for practical design scenarios. Where project specific data is required, APSDS can readily calculate stresses induced by proof rollers and aircraft at any location and depth for comparison. APSDS is a leading tool for flexible aircraft pavement thickness determination due to its flexibility, transparency and being free from bias. However, the following possible areas for improvement are considered worthy of future research and development: * Improvements to the user interface. * Ability to model aircraft masses as frequency distributions. * Ability to copy stress with depth data to Excel(tm) spreadsheets. * Ability to perform parametric runs. * Inclusion of a reliability based design module.
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Valjavec, Marko 1969. "A closed-loop shape control methodology for flexible stretch forming over a reconfigurable tool." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/9428.
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Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1999.Includes bibliographical references (p. 239-246).
Today stretch forming of sheet metal parts and associated tool design methods used in the aerospace industry are still more an art than a science. Few analytical tool design techniques exist and even fewer are used in practice. When they are, they only address the result but not the cause of the forming anomalies. Rigid tooling, fixed-configuration facilities and dependence on tool designers' expertise are the major drawbacks of modern tool design. tool fabrication result in long lead times, high manufacturing costs and insufficient product quality. In response to this, a methodology combining a self-tuning shape control algorithm and reconfigurable forming tool is developed and implemented for stretch forming. This methodology is based on empirical estimation of the process characteristics from the calibration forming trials, and is capable of generating a tool shape that produces, upon the impact of unloading and in-process variations, the final part shape of desired precision. The methodology is based on a new system identification strategy, where the effect of decreasing signal magnitudes on the transfer function estimate is greatly alleviated. The assumption that the change in tool shape is linearly related to the corresponding change in part shape proved to accurately capture the stretch forming characteristics. The relative stability analysis shows that the final part shape converges to the designed shape despite significant alterations of the calibration die shape and proportional controller gain. Moreover, a sapient selection of the calibration dies improves convergence of the tool design process without sacrificing the part accuracy. Finally, the same methodology is employed to compensate for combined shape distortions caused by the stretch forming, chemical milling and trimming operations. The experiments involving various compound curvature stretch formed skins and cylindrical parts ensuing from the successive stretch forming, chemical milling and trimming operations are used to validate the effectiveness of this methodology to reduce shape errors. The final maximal shape errors were reduced below a tolerance (0.010 in.) in just one or two closed-loop forming trials regardless of skin shape. The major obstacles in achieving even higher final part shape fidelity are in the mechanical properties of the interpolation, and in one case, in the stretch forming press design.
by Marko Valjavec.
Ph.D.
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Hoefener, Carl E., and Dennis Beech. "GPS Provides a Flexible Tool for TSPI Regardless of Type of Vehicle Being Tested." International Foundation for Telemetering, 1989. http://hdl.handle.net/10150/614703.
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International Telemetering Conference Proceedings / October 30-November 02, 1989 / Town & Country Hotel & Convention Center, San Diego, CaliforniaThe test scenarios of vehicles under test vary greatly depending upon the type of vehicle being tested. This paper will examine the test characteristics of a variety of vehicles and the TSPI requirements of each. The types of platforms to be investigated range from soldiers, jeeps, tanks, helicopters and high performance aircraft to ballistic missiles, air-air, air-ground and ground-air missiles in addition to space vehicles. Each of these platforms exhibits different dynamics and therefore require varying capabilities in the TSPI technique utilized. Selecting the optimum GPS TSPI system for each vehicle and its particular test scenario can present problems to the instrumentation system designer. A comparison of vehicle dynamics, vehicle size, and GPS instrumentation capability will be made so that an optimum GPS instrumentation technique can be selected. This may vary from a single channel C/A-Code man-pack receiver for the soldier, to a multi-channel inertial aided P-Code receiver for the high performance aircraft to a GPS frequency translator tracking system for missiles and space vehicles. This will enable sizing and the selection of the most desirable GPS instrumentation system for each test application.
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Er, Basak. "The Evolving Concept Of Flexible Integration Within The European Union: A Tool For Managing Diversity?" Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605525/index.pdf.
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This thesis scrutinizes &ldquoflexible integration&rdquo
as an evolving concept within the European Union. It aims to understand the framework in which the debate on flexibility has taken place before the institutionalisation of the mechanism with the Treaty of Amsterdam through examining the different conceptualisations, past examples and the political debate associated with these examples. After analysing the Treaty provisions on flexible integration, the thesis attempts to answer the question whether this mechanism can be perceived as a tool for managing diversity in economic and political sense.
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SILVA, ILDELANO FERREIRA E. "DEVELOPMENT, VALIDATION AND APPLICATION OF A FLEXIBLE TOOL FOR THE SIMULATION OF CELLULAR MOBILE SYSTEMS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2002. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=2688@1.
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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOREste trabalho descreve uma ferramenta de simulação esenvolvida para analisar o gerenciamento dos recursos de rádio e parâmetros de QoS (Quality of Service) dos sistemas móveis celulares. Pela natureza de um sistema real de telefonia celular, é extremamente difícil que as variáveis de saída de um simulador sejam derivadas de um conjunto real de funções. Isso se deve à grande quantidade de parâmetros que devem ser considerados no comportamento da mobilidade, nas condições de tráfego, nas características geográficas e morfológicas da região, na modelagem complexa do canal rádio propagação móvel, entre outras. Visando a desenvolver uma ferramenta de simulação próxima da realidade, adotam-se modelos de propagação, de mobilidade e de tráfego que sejam satisfatoriamente adequados ao caso real. A contribuição deste trabalho é oferecer uma ferramenta de simulação flexível, aqui adequada ao sistema norte-americano TDMA (IS-136), que possibilite ao usuário, além de analisar a capacidade do sistema,também avaliar novos algoritmos de controle de potência, novas estratégias de handoff, novos esquemas de alocação de canal e modelos de propagação. A ferramenta será validada seguindo o processo de um projeto real de telefonia celular e ao final, será aplicada a um sistema celular com sobreposição macro-células/micro-células, analisando-se algumas estratégias de handoff dedicadas a esses sistemas.
This work describes a simulation tool, which was developed to analyze the radio resources and QoS (Quality of Service) parameters in mobile systems. Because of the complex characteristics of an actual cellular network, it is extremely difficult having the outputs of the simulator being derived from a real set of functions, due to the large amount of parameters that have to be considered such as the mobility behavior, the traffic conditions, the geographic and morphologic characteristics of the region, the complex modeling of mobile radio propagation channel, and so on. In order to develop a simulation tool as near as possible to the reality, models that are satisfactorily adequate to the real case have been considered. So, propagation, mobility and traffic models were adapted from the IS-136 American system. The contribution of this work is to offer a flexible simulation tool that allows the user, in addition to analyzing the capacity of the system, to evaluate new algorithms of power control, handoff strategies, channel allocation schemes and propagation models. The tool will be validated following the process of a real project of cellular telephony and at the end, it will be applied to a cellular system with overlapped macro- cells/micro-cells, and some handoff strategies dedicated to those systems will be analyzed.
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Lam, Aaron C. L. "A flexible tool design and integrated modelling techniques for springback compensation in creep-age forming." Thesis, Imperial College London, 2015. http://hdl.handle.net/10044/1/44465.
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This thesis presents the development of ad-hoc experimental and integrated modelling techniques for springback compensation in creep-age forming (CAF). A test programme is presented which describes the material and workpiece information and the test plans for the experimental evaluation of the creep-ageing and springback behaviour of aluminium alloy 7B04-T651 under 115 oC. Experimental results from the creep-ageing and tensile tests were used to determine a CAF material model for the alloy. A flexible tool design has been proposed and a laboratory-scale prototype has been delivered and used to perform the CAF tests in this research. The determined CAF material model and geometry of the flexible tool design were treated as input and used to construct a CAF process model using finite element (FE) method. Comparisons between final deflections of FE-simulated and experimentally formed plates validated the springback predictive ability of the FE process model. The model was eventually employed to model springback-compensated tool shapes and using the modelled tool shapes to perform CAF tests have produced formed plates that have an average 0.81±0.14 mm of maximum absolute vertical difference from target shape. CAF can now be used to produce accurately shaped panel components in a laboratory environment using the equipment and techniques developed in this research.
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Agrawal, Vaibhav. "A web-application tool for manufacturing systems strategic management and competitive performance monitoring /." free to MU campus, to others for purchase, 2004. http://wwwlib.umi.com/cr/mo/fullcit?p1426042.
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Spång, Magnus. "Skapandet av ”Effect: A prototype for an Easy to use, Flexible, Figurative and Extendable Configuration Tool." Thesis, Linnaeus University, School of Computer Science, Physics and Mathematics, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-5954.
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Den här rapporten avhandlar framtagandet av en prototyp för en tjänst där abonnenter hos telekomoperatörer ska kunna beställa och konfigurera sina egna tjänster i betydligt större utsträckning än vad som är möjligt idag.
Detta är möjligt och önskvärt tack vare att det pågår kontinuerlig modernisering av den teknik som idag används i telefonnät och telefonsystem.
Projektet genomfördes på uppdrag av Tieto i Kalmar som är ett konsultföretag som arbetar mycket med telekomteknik och som har flera stora kunder som arbetar med modernisering av sin teknik.
Resultatet har blivit en prototyp där användaren på ett flexibelt sätt kan skapa, redigera och radera sina egna tjänster, samt få en grafisk överblick över sina inställningar.
Prototypen är också enkel för uppdragsgivaren att anpassa för demonstration för olika kunder. Den är dessutom anpassad så att det ska gå så enkelt som möjligt att utveckla den vidare med nya komponenter.
Från början ingick en student från Rehabiliteringsprogrammet i projektet. Tanken var att kunna genomföra olika typer av användbarhetsanalyser och på så sätt göra prototypen så användarvänlig som möjligt. Då studenten av personliga skäl inte fullföljde projektet redovisas dessa delar av projektet inte i den här rapporten.
This thesis treats the development of a prototype for a service where telecom customers can order and configure their own services to a much higher degree than what is possible today.
This is possible and desireble due to a continuing modernisation of the technology beeing used in the telecom systems today.
The project was coducted on the request of Tieto, Kalmar. Tieto is a consulting company that is highly involved in the telecom industry and has several customers that are working with modernisation their technology.
The result is a prototype called: ”Effect: a prototype for an Easy to use, Flexible, Figurative, Extenable Configuration Tool”. It´s a web application where the users in a flexible way can order, configure and delete their own services, and also get an graphical overview of their settings.
The prototype is easy for Tieto to adjust when showing it to different customers. It is also adapted in a way that it is easy to extend it with new components.
In the beginning the project included a student från the Interaction design program. The idea was to conduct a series of usability analysis and with the help of that being able to make the prototype as user friendly as possible. Since the student, for personal reasons, did not finnish the projet, this report will not present anything on that part.
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Zhu, Xinjie, and 朱信杰. "START : a parallel signal track analytical research tool for flexible and efficient analysis of genomic data." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2015. http://hdl.handle.net/10722/211136.
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Signal Track Analytical Research Tool (START), is a parallel system for analyzing large-scale genomic data. Currently, genomic data analyses are usually performed by using custom scripts developed by individual research groups, and/or by the integrated use of multiple existing tools (such as BEDTools and Galaxy). The goals of START are 1) to provide a single tool that supports a wide spectrum of genomic data analyses that are commonly done by analysts; and 2) to greatly simplify these analysis tasks by means of a simple declarative language (STQL) with which users only need to specify what they want to do, rather than the detailed computational steps as to how the analysis task should be performed.
START consists of four major components: 1) A declarative language called Signal Track Query Language (STQL), which is a SQL-like language we specifically designed to suit the needs for analyzing genomic signal tracks. 2) A STQL processing system built on top of a large-scale distributed architecture. The system is based on the Hadoop distributed storage and the MapReduce Big Data processing framework. It processes each user query using multiple machines in parallel. 3) A simple and user-friendly web site that helps users construct and execute queries, upload/download compressed data files in various formats, man-age stored data, queries and analysis results, and share queries with other users.
It also provides a complete help system, detailed specification of STQL, and a large number of sample queries for users to learn STQL and try START easily. Private files and queries are not accessible by other users. 4) A repository of public data popularly used for large-scale genomic data analysis, including data from ENCODE and Roadmap Epigenomics, that users can use in their analyses.published_or_final_version
Computer Science
Doctoral
Doctor of Philosophy
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HADLOCK, NATHANIEL A. "MINIMALLY INVASIVE SURGICAL DEVICES WITH MICRO FORCE SENSORS: A SMART SCALPEL AND DISSECTOR TOOL." University of Cincinnati / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1165005105.
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Marciszko, Tobias. "A tool for optimized layout of flat cable harnesses for future on-board cabling systems in cars." Thesis, Linköping University, Department of Computer and Information Science, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-2325.
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Current cabling systems in cars are about to be, completely or partially, replaced by a cabling technology called flexible flat cables, FFCs. This new technology requires tools that can assist engineers in the design process of the cable layouts. The aim of this thesis is to develop a software demonstrator of a concept tool for this purpose.
The task is divided into three problem areas. Topology modeling, optimization and visualization. An editor is to be implemented which handles creation and modification of topologies which represents FFC harnesses. The optimization is performed using global and local routing. The global routing handles optimization on topology level, defining net paths in the topology. Local routing handles the exact net placement on each bus cable. Finally, the local routing solutions should be graphically presented to the user.
The topology modeling requirement was implemented as a graph layouteditor. Global routing is performed using graph search techniques and local routing is based on VLSI channel routing methods. Visualization is implemented for the local routing solutions using the SVG format.
The developed application handles most of the requirements. The editor has support for an XML netlist which is used for specifying connectors and nets used in the topology. Global routing and local routing can be performed on the topology. Prerouting of nets can be performed on both global and local level. Support for assigning specific cables, from a library, to bus cables is possible.
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Petrova, Natalia. "Flexible working as an effective tool of organizational productivity increasing: perspectives of property and staff in Alcatel-Lucent Pte. Ltd." Thesis, KTH, Bygg- och fastighetsekonomi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-77018.
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Continuous information technology development changed traditional ways of management and business operations. Nowadays there is a high demand for new innovative business solutions and the ways of managing people that enables to fully elicit their potential. Physical boundaries are removed; work is becoming incredibly dispersed around the world enabling growth of 24/7 customer service, home banking, online shopping and other services that were seemed incredible just a few years ago. In this fast paced environment the companies are seeking for any possibility to increase their competitiveness. Implementing flexible working is considered by most of organizations as a tool to adapt to never-ending changes. This paper aims to test the hypothesis that flexible working increases organizational productivity from the perspective of the property as well as from the perspective of employees. In current work organizational productivity from the perspective of property is analyzed from economic standpoint when flexible working decreases operational and real estate costs per employee, thus, allowing saving and investing in other business areas that would increases profitability of the company. Productivity from staff perspective is measured by employee's satisfaction of his working environment, work-life balance, and increased efficiency through team collaboration, flexible hours and telecommuting. Methodology used is case study and literature review. Case study was performed on-site in Alcatel-Lucent in Singapore. It is limited to six months from planned full year of 3 implementation project. Set of interviews with company managers was conducted to support the case results. The thesis suggests the hypothesis, according to the literature review and overview of some cases in different countries, that flexibility in property as well as in working mode increases productivity both in terms of real estate costs savings and in terms of employee’s increased productivity due to better team collaboration in open space, flexible working hours, ability to choose preferred location for work, telecommuting that creates a positive work-life balance. The case study performed for this paper in Alcatel-Lucent Singapore shows that the aforementioned benefits are not there yet due to the project timeline but are highly anticipated by local and global management. Nevertheless, thorough assessment of business requirements and the needs of employees should be undertaken before deciding on flexible working. It is extremely crucial to secure efficient and open internal communication and employees’ involvement in all stages of the project in order to achieve fast acceptance and adaptation to new environment. Based on the current example, future research suggests investigating in cultural aspect of global strategy deployment by corporate decision in different countries.
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Rygl, Ondřej. "Rozdělení a aplikace matic flexibilního prototypového nástroje." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2014. http://www.nusl.cz/ntk/nusl-231743.
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The price of the tools for making prototypes and small series of products, as well as the cost of additional changes in the tool are quite high and increase the price of the final product. A flexible tool provides an advantageous solution to create a wide variety of molds. In this thesis the area of flexible tooling is introduced. An experimental mechanism has been manufactured and tested. With the help of a methodical approach several solutions for a flexible tool design have been proposed. Based on the evaluation of all given criteria, the most suited version has been designed and manufactured. The tool has been tested and evaluated for the thermoforming process. Improvements and potential applications have been suggested. The results show that the flexible tool has some limitations but has a broad potential use in several applications.
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Bojnell, Kim, and Mattias Feltendal. "Development of a flexible stand to position a microwave transmitter : A complimentary tool to test equipment for breast cancer research." Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-55146.
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Breast cancer is the most common form of cancer among women, this type of cancer is diagnosed in around 9000 women every year in Sweden. The most common studies to find breast cancer is through mammography where the breast tissue is compressed and exposed by radiation. Not only does the technique expose the breast tissue for radiation, but it can also be very uncomfortable. There is research on a new kind of scanning where use of microwaves reduces the uncomfortable situation. The MDH research team that are working with this technology needs help to position a transmitter of microwaves to test their equipment. The purpose of this paper is to discover a way to mechanically position a transmitter so that it can be moved along a breast model. The investigation will be made through a product development process in order to review the research question: RQ: “How can a product be designed to position and adjust a microwave transmitter to various locations in order to help testing of cancer research equipment?” By using an agile working methodology in combination with a Design thinking process this thesis includes several sprints that involved continues improvement and feedback from the research team. The first sprint was mostly to discover and experiment on new design ideas as well as control if any of them could work. It resulted in need of measurement changes and redesigning. The second sprint involved measurement corrections. The model itself had the reasonable measurements and the functions worked as expected. However, some of the functions needed to be improved as well as a problem with clearing of the wires to the transmitter itself. The third sprint included changes where more freedom was given and more clearance was made for the wires, but this design turned out to be unpredictable. The fourth sprint included a completely new design to stabilizing the prototype as a result from the researchers’ feedback. To answer the research question, the final design resulted in a 3D printed stand designed to move the transmitter along x-axis as well as rotate around y-axis to adjust to different breast diameters and forms. The stand also includes a rack and pinion design that makes it possible to adjust to different breast lengths. Lastly, the stand makes it possible to gradually move the transmitter around the breast model. However, the final design does not only answer the research question it also fulfils stability and functionality requirements set by the research team. This clarifies why the first iterations needed redesigning. Therefore, the stand is ready for preliminary tests of the researcher’s equipment. To conclude, there are many different design solutions that can answer the research question. However, the design requires stability which reduce the number of design solutions.
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Sowgath, Md Tanvir. "Neural network based hybrid modelling and MINLP based optimisation of MSF desalination process within gPROMS : development of neural network based correlations for estimating temperature elevation due to salinity, hybrid modelling and MINLP based optimisation of design and operation parameters of MSF desalination process within gPROMS." Thesis, University of Bradford, 2007. http://hdl.handle.net/10454/10998.
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Desalination technology provides fresh water to the arid regions around the world. Multi-Stage Flash (MSF) distillation process has been used for many years and is now the largest sector in the desalination industry. Top Brine Temperature (TBT) (boiling point temperature of the feed seawater in the first stage of the process) is one of the many important parameters that affect optimal design and operation of MSF processes. For a given pressure, TBT is a function of Boiling Point Temperature (BPT) at zero salinity and Temperature Elevation (TE) due to salinity. Modelling plays an important role in simulation, optimisation and control of MSF processes and within the model, calculation of TE is therefore important for each stages (including the first stage, which determines the TBT). Firstly, in this work, several Neural Network (NN) based correlations for predicting TE are developed. It is found that the NN based correlations can predict the experimental TE very closely. Also predictions of TE by the NN based correlations were found to be good when compared to those obtained using the existing correlations from the literature. Secondly, a hybrid steady state MSF process model is developed using gPROMS modelling tool embedding the NN based correlation. gPROMS provides an easy and flexible platform to build a process flowsheet graphically. Here a Master Model connecting (automatically) the individual unit model (brine heater, stages, etc.) equations is developed which is used repeatedly during simulation and optimisation. The model is validated against published results. Seawater is the main source raw material for MSF processes and is subject to seasonal temperature variation. With fixed design the model is then used to study the effect of a number of parameters (e.g. seawater and steam temperature) on the freshwater production rate. It is observed that, the variation in the parameters affect the rate of production of fresh water. How the design and operation are to be adjusted to maintain a fixed demand of fresh water through out the year (with changing seawater temperature) is also investigated via repetitive simulation. Thirdly, with clear understanding of the interaction of design and operating parameters, simultaneous optimisation of design and operating parameters of MSF process is considered via the application MINLP technique within gPROMS. Two types of optimisation problems are considered: (a) For a fixed fresh water demand throughout the year, the external heat input (a measure of operating cost) to the process is minimised; (b) For different fresh water demand throughout the year and with seasonal variation of seawater temperature, the total annualised cost of desalination is minimised. It is found that seasonal variation in seawater temperature results in significant variation in design and some of the operating parameters but with minimum variation in process temperatures. The results also reveal the possibility of designing stand-alone flash stages which would offer flexible scheduling in terms of the connection of various units (to build up the process) and efficient maintenance of the units throughout the year as the weather condition changes. In addition, operation at low temperatures throughout the year will reduce design and operating costs in terms of low temperature materials of construction and reduced amount of anti-scaling and anti-corrosion agents. Finally, an attempt was made to develop a hybrid dynamic MSF process model incorporating NN based correlation for TE. The model was validated at steady state condition using the data from the literature. Dynamic simulation with step changes in seawater and steam temperature was carried out to match the predictions by the steady state model. Dynamic optimisation problem is then formulated for the MSF process, subjected to seawater temperature change (up and down) over a period of six hours, to maximise a performance ratio by optimising the brine heater steam temperature while maintaining a fixed water demand.
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Arendt, Thorsten [Verfasser], and Gabriele [Akademischer Betreuer] Taentzer. "Quality Assurance of Software Models - A Structured Quality Assurance Process Supported by a Flexible Tool Environment in the Eclipse Modeling Project / Thorsten Arendt. Betreuer: Gabriele Taentzer." Marburg : Philipps-Universität Marburg, 2014. http://d-nb.info/1052995144/34.
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Dubaj, Ondrej. "Systém pro správu výsledků testů doplňující nástroj tmt." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2021. http://www.nusl.cz/ntk/nusl-445546.
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This diploma thesis deals with the area of software testing, more precisely with the topic of managing test results. The aim of this work is to find, set up and implement a system that complements the missing functionality of the TMT tool, which is going to replace the Nitrate tool in Red Hat as a test management system. The content of this work is a basic introduction to the tools Nitrate, TMT and other technologies used in Red Hat. Furthermore, the work presents the current state of the test infrastructure and collected user requirements for a new system for managing test results. Subsequently, the ReportPortal tool is introduced as a system for test results management and the missing functionality is defined. The rest of the work is devoted to setting up the system itself and implementing the missing functionality, along with implementing the infrastructure needed to import test results into ReportPortal. The work describes the method of deploying the system in use and feedback from users. The deployed system is evaluated and its further possible improvements are discussed.
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Vetiška, Jan. "Analýza stability řezného procesu obráběcího stroje vzhledem k samobuzenému kmitání." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-234199.
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The thesis deals with building and utilization of mechatronic models which are based on modeling of system of rigid and flexible bodies. Such models are then used for analysis of behavior of complex systems, for instance machine tools. The work is concentrated on analysis of self-excitation of a machine tool. The appearance of the self-excitation during the machining may be influenced by several methods described in the work. The evaluation of the appearance of the self-excitation is analyzed via so called lobe diagram. It is necessary to know transfer function describing the impact of acting forces on the deformation of the system (machine tool in this case) for compilation of the lobe diagram. The whole structure of the model shows compliant behavior which dramatically influences the transfer function thus the approach to the modeling of mechanical parts as flexible bodies is proposed. There are created models of modally reduced flexible bodies based on modified CAD models which have same modal properties as non-reduced FEM models up to the maximal excitation frequency. The reduced models have significantly lower number of degrees of freedom and it is possible to work with them in multi-body simulation tools and at the same time they contain the information about the deformations. The work utilizes Graig-Bamton method which is implemented to the ANSYS. The whole model is consequently built and analyzed in ADAMS. It is possible to export the linearized model of the system in form of state matrices which are used for writing of the transfer function. The conditions of stability of the machining process are then evaluated via the lobe diagram. The proposed thesis presents the modeling of mechatronic systems with stiff and rigid bodies. The approach may be used for analysis of machining tools as well as for development of advanced mechatronic systems with active damping, etc.
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Vanneste, Thomas. "Développement d'un outil de modélisation aéroélastique du vol battu de l'insecte appliqué à la conception d'un nano-drone résonant." Thesis, Valenciennes, 2013. http://www.theses.fr/2013VALE0021/document.
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Développer, à partir de zéro, un drone imitant le vol battu de l'insecte est une tâche ambitieuse et ardue pour un designer en raison du manque de savoir-faire en la matière. Pour en accélérer le développement pendant les phases de design préliminaires, un outil modélisant les phénomènes aéroélastiques du vol de l'insecte est un véritable atout pour le designer et est le sujet de cette thèse. Le cœur de cet outil est un solveur éléments finis 'structure' couplé, en utilisant une approche par tranche, à un modèle aérodynamique quasi-statique du vol de l'insecte prenant en compte la flexibilité de l'aile, à la fois selon l'envergure et la corde, mais aussi ses grands déplacements. L'ensemble est conçu de manière à contenir le coût de calcul tout en étant assez modulaire pour s'adapter à un large panel d'applications. Afin de valider l'intégralité de cet outil, un processus en deux étapes a été entrepris avec d'abord une approche numérique et ensuite une validation expérimentale grâce à un banc de caractérisation dédié. Les résultats du modèle concordent de manière satisfaisante dans les deux cas, capturant l'amortissement dû aux forces aérodynamiques, et ouvrent ainsi la voie à son utilisation pour le design de drones à ailes battantes. Pour démontrer l'intérêt de cette approche lors des phases de design préliminaires, deux applications sur un nano-drone résonant sont réalisées: la définition d'une stratégie d'actionnement efficace et la recherche d'une géométrie d'aile potentiellement intéressante d'un point de vue aérodynamique, en couplant l'outil de modélisation à un algorithme génétique. Les résultats obtenus sont cohérents avec ceux trouvés dans la nature et sont en cours d'implémentation sur le droneDeveloping insect-like flapping-wing drones from scratch is an ambitious and arduous task for designers due to a lack of well-established know-how. To speed up the development of such vehicles through the preliminary design stage, a framework modeling the aeroelastic phenomena encountered in insect flight is an asset and is the subject of this thesis. Its kernel is a FEM based structural solver coupled in a blade-element approach to a quasi-steady aerodynamic model of insect flight accounting for the wing flexibility, both in the spanwise and in the chordwise direction, and for its large displacement. The complete framework is devised so as to maintain the computation load low while being modular enough for a wide range of applications. To validate the overall aeroelastic framework, a two-steps process has been undertaken with in one hand numerical studies and in the other hand experimental ones acquired on a dedicated test bench. The framework computation agrees satisfactorily, capturing the damping due to the aerodynamic force, and thus paves the way for preliminary design applications of a flapping-wing vehicle. To exhibit the capabilities of the framework as a preliminary design tool, two applications on a resonant nano air vehicle are performed: the definition of an efficient actuation strategy and the search of an aerodynamic potentially interesting wing geometry by plugging the framework to a genetic algorithm. The results are coherent with the ones found in nature and are under implementation on the nano air vehicle
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Štetina, Jakub. "Simulační posouzení možností tlumení osy X těžkého obráběcího stroje." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2014. http://www.nusl.cz/ntk/nusl-231348.
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This master's thesis deals with the simulation assessment of axis X damping possibilities of Heavy Machine Tools. CAD model has been provided by company TOSHULIN a.s. In the thesis, there is described modelling of axis X as multi body system consisting of rigid and flexible bodies. The main goal is to create simplified model and get the information for strategic decision of manufacturer about damping possibilities of axis X. For the solution has been used several software products: SolidWorks 2013 - for simplifying the CAD models, Ansys 14.5. for modelling od flexible bodies, MSC.Adams for modelling multi body systems and Matlab 2012 for data processing and optimization.
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Provasi, Rodrigo. "Contribuição ao projeto de cabos umbilicais e tubos flexíveis: ferramentas de CAD e modelo de macro elementos." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/3/3152/tde-29072013-120723/.
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A Engenharia Offshore está sempre em evolução, motivada pela busca de novos poços de petróleo, o que acarreta em maiores lâminas dágua e demanda novas tecnologias que tornem o processo viável. Neste contexto, não apenas novos tipos de plataformas são desenvolvidas, mas também novos tipos de tubos flexíveis e cabos umbilicais. A maior dificuldade de gerar esses novos tipos de cabos é determinar a sua viabilidade. Tubos flexíveis e cabos umbilicais são de difícil modelagem, devido à interação entre as camadas, além de difícil concepção, dada a grande variedade de componentes e o grande número de configurações possíveis. O processo de concepção desses cabos é baseado nas funções que os elementos que os compõem têm de cumprir, levando aos tipos de componente que serão utilizados. O processo consiste em definir as funções que o cabo deverá executar e selecionar os elementos que o irão compor. Esse processo deve levar em conta as características estruturais e respeitar restrições definidas no projeto. Com o objetivo de tornar o processo de concepção desses cabos menos laboriosa, propõe-se neste trabalho uma ferramenta computacional do tipo CAD (do inglês Computer Aided Design), bem como um modelo de mecânica interna para tratar da interação entre as camadas. A ferramenta CAD aqui proposta difere das demais por facilitar em muito a definição do cabo e de suas funções. Ela inclui ainda ferramentas de verificação da configuração final através de um modelo 3D. Ela permite ao usuário criar uma configuração totalmente nova a partir de uma biblioteca de elementos previamente definido. O software ainda oferece a visualização tridimensional, que facilita a verificação de certos erros de projeto intrínsecos a esses tipos de cabo bem como a visualização de resultados advindos do modelo. Outra possibilidade que o CAD traz é a utilização de seus módulos bi e tridimensional como pré e pós processadores de outros modelos, não somente o proposto aqui. Isso aumenta em muito as possibilidades de utilização. Propõe-se um modelo de elementos finitos com elementos feitos sob medida, denominados aqui como macro-elementos. Nessa modelagem, os elementos são descritos com mais detalhes, procurando levar em conta as características dos elementos físicos que pretendem representar, minimizando o número de elementos necessários para descrever o problema como um todo. Com esse tipo de abordagem, pretende-se utilizar todas as potencialidades dos modelos numéricos, como por exemplo o abrandamento de certas hipóteses, com as do modelo analítico, incorporando características do elemento físico no modelo matemático. Nesse trabalho propõe-se elementos cilíndricos para capas e tubos equivalentes, elementos de tendão e elementos de ligação e contato.The offshore industry is in constant evolution due to the need of reaching new oil fields in increasingly water depths. In this scenario, not only new types of platforms are being designed, but also new types of flexible pipes and new umbilical cable configurations. The greatest difficulty to generate a new concept for a riser is to determine if it is viable or not. Flexible pipes and umbilical cables are complicated to model, due to the interactions between their layers, and to design, due to the great variety of components and possible arrangements. The design of those elements is based on the functions they are intended to perform, leading to the elements that will be selected. The process consists on defining the cable features and selecting the elements that will compose it. The process should take into account the desired structural characteristics and must respect constraints defined in the project. Aiming to turn the conception of these cables into a less laborious process, this work proposes Computer Aided Design (CAD) software, as well an internal mechanic model to deal with the layer interaction. The CAD tool proposed in this work differs from the others by making the cable definition and functions easier. It also includes tools for verification of the cable using a 3D model. It makes possible to the user to create a totally new configuration based on a predefined component library. The software also has a tri-dimensional visualization module, which makes the verification of certain errors attached to the project of such cables, as well enables the visualization of results from the model. Another possibility that the CAD offers is the use of the two and three-dimensional modules as pre- and post processors for other models, not only the one proposed here. This greatly increases its usage possibilities. It is also proposed a finite element model with custom-made elements, called here macro-elements. In this modeling, the elements are described with more details, taking into account the characteristics of the targeted physical elements, minimizing the number of the necessary elements to describe the problem as a whole. With this kind of approach, one intends to utilize all the potentialities from both numerical models, such as the relaxation of certain hypothesis, and analytical models, bundling into the mathematical model the physical characteristics of the element. It is proposed in this work cylindrical elements for sheaths and equivalent tubes, tendon elements and contact and connection elements.
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Bertoldi, Evandro. "Desenvolvimento de método e ferramenta para aplicação submarina de clamps de reparo de dutos ou proteção de sistemas de monitoramento." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2018. http://hdl.handle.net/10183/178216.
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O escoamento entre o poço marítimo e a unidade flutuante é realizado através de dutos definidos como risers. Os risers flexíveis são compostos por camadas intercaladas de diferentes materiais, como aço e polietileno, o qual cada camada possui uma função. Os mecanismos de falha mais reportados são referentes a danos na camada externa polimérica, o que leva à exposição de suas armaduras metálicas ao meio externo. Os risers rígidos são dutos fabricados normalmente em aço, formados por segmentos de dutos unidos por soldas, onde a causa de dano mais frequente é a corrosão. Tem-se como objetivo nesta dissertação, o projeto e desenvolvimento de uma ferramenta e de um método para operações submarinas em risers. A ferramenta deverá ser capaz de aplicar de forma automática, um clamp bipartido no reparo da camada externa polimérica de risers flexíveis, ou acoplar sistemas de monitoramento em risers rígidos. Já o método, deverá permitir a sua aplicação tanto no reparo quanto na proteção do sistema de monitoramento. Para isto, realizou-se uma revisão bibliográfica a fim de obter uma melhor compreensão sobre o tema estudado. Desenvolveu-se o projeto do método e da ferramenta, e, posteriormente, construiu-se o protótipo para a realização de testes de funcionamento em um duto rígido Por último, através de ensaios hidrostáticos de pressão interna e externa, realizaram-se ensaios para avaliação do comportamento do método aplicado em um duto rígido. Os ensaios comprovaram a eficácia do clamp quando aplicado em ambientes submarinos em grandes profundidades, porém apresentou vazamentos nos ensaios de pressão interna e externa. A resina epóxi utilizada não garantiu a estanqueidade, possivelmente devido a sua alta rigidez, aderência ineficaz em superfícies metálicas, ou presença de vazios ou porosidades. O ensaio de pressão interna indicou que as deformações não ultrapassaram o regime elástico tanto do duto quanto do clamp até aproximadamente 182 bar de pressão. No regime elástico, o ensaio apresentou deformações menores no clamp em relação ao duto, possivelmente porque a resina acabou absorvendo as deformações. O método demonstrou ser eficiente como recipiente para a resina, e também permitiu a montagem e fixação de um colar de sensores no seu interior. Os testes de funcionamento mostraram que a ferramenta projetada e construída mostrou-se adequada para a aplicação automática de um clamp bipartido em risers, e o método mostrou-se adequado para sua aplicação em risers, tanto no reparo quanto na proteção do sistema de monitoramento.The drain between the maritime oil well and the floating unit is made trough pipes, which is defined as risers. The flexible risers are composed by alternate layers from different materials as steel and polyethylene, each layer has its function. The failure mechanisms more reported are referent to the damage in the external polymeric layer which leads to the exposition of the metal armature to the outside. The rigid risers are pipes usually fabricated in steel made by ducts segments connect by spot welding, where the most common damage is corrosion. This essay aims to project and create a tool and a method for submarine operations in risers. The tool must be able to apply, in an automatic way, a bipartite clamp in the repair of the flexible rises in external polymeric layer or to attach monitoring systems to the rigid risers. The method must allow its application in the repair as much as the monitoring system protection. For this, it was made a bibliographic review to obtain a better comprehension from the studied theme. A project from the method and a tool were developed, later a prototype was built to make the operation tests in a rigid pipe. At last, by internal and external pressure hydrostatic trials, were made tests to evaluate the behavior of the method applied in a rigid pipe The trials proved the efficiency of the clamps when applied in submarine environments and in depth; however there were leaks in the internal and external pressure tests. The Epóxi resin did not guarantee the leak-tightness, possible due to its hardness, ineffective adherence in metal surfaces or presence of gaps and porosities. The internal pressure trial indicated that the deformations did not exceed the elastic regime in the pipe as in the clamp until, about 182 pressure bar. In the elastic regime, the trial presented minor deformation in the clamps related to the pipe possibly, because the resin absorbed the deformation. The method has proven efficient as recipient for the resin and also allowed the assembly and fixation of a sensor collar in its interior. The operation tests showed that the designed and built tool is proper for an automatic bipartite clamp application in risers and the method has proven proper for its application in risers in repair as much as monitoring system protection.
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Dugelas, Loic. "Stratégies probabilistes appliquées à la modélisation numérique discrète : le cas des filets pare-pierres." Thesis, Université Grenoble Alpes, 2020. https://tel.archives-ouvertes.fr/tel-02498238.
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L'objectif de ce travail de recherche est le développement d'outils numériques pour l'aide à la conception d'écrans souples de protection contre les chutes de blocs.Des modèles, basés sur la Méthode des Éléments Discrets (DEM), ont tout d'abord été développés à partir d'approches de modélisation issues de la littérature, pour deux écrans souples. La principale différence entre les deux écrans étudiés réside dans la nature de la nappe de filet : nappe à anneaux ou nappe ELITE. Pour l'écran équipé d'une nappe à anneaux, le modèle de structure développé s'est avéré suffisant pour obtenir un compromis en termes de pertinence, précision et efficacité. Par contre, pour l'écran équipé d'une nappe ELITE, de nouveaux développements numériques ont été nécessaires pour obtenir un tel compromis.L'obtention d'un modèle d'ouvrage complet efficace pour l'écran ELITE a nécessité la prise en compte du glissement entre les câbles constitutifs de la nappe. Deux approches ont été proposées pour l'intégration de ce glissement. La première approche intègre le glissement sans prendre en compte le frottement à l’interface entre les câbles, alors que la seconde permet cette prise en compte. Cependant, cette seconde approche ne peut être utilisée à l’échelle d’un ouvrage en raison de durées de calcul trop importantes.Les modèles d'écran développés ont été intégrés dans un outil d'aide à la conception, basé sur des approches de méta-modélisation. Cet outil permet de réaliser des études paramétriques et de sensibilité sur la réponse de l'ouvrage, ainsi que d'identifier les configurations optimales de l'ouvrageThis research aims at developing numerical tools to help the design of flexible fences against rockfall.Models based on the Discrete Element Method (DEM) are developed for two flexible fences, using modeling approaches taken from the literature. The main difference between the two flexible fences investigated is their interception structure: ring net or ELITE net. For the ring net flexible fence, the DEM model proved to be a sufficient compromise between relevance, accuracy, and efficiency. On the other side, for the flexible fence with a ELITE net, new numerical developments are necessary to reach such compromise.In order to get an efficient DEM model for the ELITE flexible fence, the sliding between the cables of the net has to be taken into account. Two approaches are proposed to integrate this sliding. In the first approach, the sliding is considered without friction between the cables, while in the second approach the friction is considered. However, the calculation duration obtained with the second approach was too important to integrate it into a complete fence model.The developed models have been integrated into a design assistance tool for flexible fences, based on surrogate modeling. Parametric and sensitivity analysis are carried out with this tool, and the optimal configurations of the fence are identified
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Wang, Weihua. "Tools for flexible electrochemical microfabrication /." Thesis, Connect to this title online; UW restricted, 2002. http://hdl.handle.net/1773/9854.
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Edmondson, Nigel Foden. "Economic generic automatic flexible assembly." Thesis, Loughborough University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.250963.
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Balkwill, J. D. G. "The dynamics of rotationally flexible eccentric cams." Thesis, Oxford Brookes University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363780.
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Cannava, Marcus N. "XBuild : flexible, generic, X-based user interface tools /." Online version of thesis, 1993. http://hdl.handle.net/1850/11711.
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Clements, Shaun. "On line vibration of a flexible rotor/bearing system." Thesis, University of Strathclyde, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302866.
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Wilkinson, S. P. "Development of flexible manufacturing system control algorithms using simulation tools and techniques." Thesis, Leeds Beckett University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358558.
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McQueen, Linda Blyth. "The co-incident flow of work pieces and cutting tools in a restricted category of flexible machining cells." Thesis, Loughborough University, 1993. https://dspace.lboro.ac.uk/2134/32915.
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The work reported in this thesis describes research carried out into the detailed design and operation of Flexible Machining Cells (FMC) incorporating automated work and tool flow, dual flow. Three modes of cell management are considered for dual flow cells, where the author examines both their operational and economic performance. A framework is defined for investigating these dual flow cells, and a structured approach providing a novel and detailed modelling capability is described. The question of how this approach compares to single flow modelling and the additional or alternative requirements for dual flow modelling is examined via the following key areas; the specification of material handling requirements, tool transportation and issue and finally, the control required to examine the interaction between the two flows operating concurrently. The framework is tested for its industrial applicability via an industrial case study. A major aim of this study is to examine the view that a hybrid cell management strategy, competitive management, could outperform the other strategies examined. The aim of this methodology is to provide a solution for the control of FMCs. Emphasis is placed on the ease of control and how the loading and control rules selection can maximise economic enhancement of a cells performance.
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Moreira, Andreza Cristina Beezão. "O problema de minimização de trocas de ferramentas." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/55/55134/tde-06012017-104534/.
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Especialmente nas últimas quatro décadas, muitos estudos se voltaram às variáveis determinantes para a implementação efetiva de sistemas flexíveis de manufatura, tais como seu design, sequenciamento e controle. Neste ínterim, o manejo apropriado do conjunto de ferramentas necessárias para a fabricação de um respectivo lote de produtos foi destacado como fator crucial no desempenho do sistema de produção como um todo. Neste trabalho, abordamos a otimização do número de inserções e remoções de ferramentas no magazine de uma ou mais máquinas numericamente controladas, admitindo-se que uma parcela significativa do tempo de produção é dispensada com estas trocas de ferramentas. De forma mais precisa, a minimização do número de trocas de ferramentas consiste em determinar a ordem de processamento de um conjunto de tarefas, bem como o carregamento ótimo do(s) compartimento(s) de ferramentas da(s) máquina(s), a fim de que o número de trocas seja minimizado. Como demostrado na literatura, mesmo o caso restrito à existência de apenas uma máquina de manufatura (MTSP, do inglês Minimization of Tool Switches Problem) é um problema NP-difícil, o que pode justificar o fato observado de que a maioria dos métodos de solução existentes o abordam de maneira heurística. Consequentemente, concluímos que a extensão ao contexto de múltiplas máquinas é também um problema NP-difícil, intrinsecamente complicado de se resolver. Nosso objetivo consiste em estudar formas eficientes de otimizar o número de trocas de ferramentas em ambientes equipados com máquinas flexíveis de manufatura. Para tanto, abordamos o problema básico, MTSP, e duas de suas variantes, em níveis crescentes de abrangência, que consideram o sequenciamento de tarefas em um conjunto de: (i) máquinas paralelas e idênticas (IPMTC, do inglês Identical Parallel Machines problem with Tooling Constraints); e (ii) máquinas paralelas e idênticas inseridas em um ambiente do tipo job shop (JSSPTC, do inglês Job Shop Scheduling Problem with Tooling Constraints). Classificamos as principais contribuições desta tese com respeito a três aspectos. Primeiramente, empurramos as fronteiras da literatura do MTSP propondo formulações matemáticas para os problemas IPMTC e JSSPTC. Desenvolvemos, também, algoritmos baseados em diferentes técnicas de resolução, como redução de domínio, Path relinking, Adaptive large neighborhood search e a elaboração de regras de despacho. Por último, com o intuito de bem avaliar a eficiência e o alcance de nossos métodos, propomos três novos conjuntos de instâncias teste. Acreditamos, assim, que este trabalho contribui positivamente com pesquisas futuras em um cenário abrangente dentro da minimização das trocas de ferramentas em um sistema flexível de manufatura.Several studies, especially in the last four decades, have focused on decisive elements for the effective implementation of flexible manufacturing systems, such as their design, scheduling and control. In the meantime, the appropriate management of the set of tools needed to manufacture a certain lot of products has been highlighted as a crucial factor in the performance of the production system as a whole. This work deals with the optimization of the number of insertions and removals from the magazine of one or more numerical controlled machines, assuming that a significant part of the production time is wasted with such tool switches. More precisely, the minimization of tool switches problem (MTSP) consists on determining the processing order of a set of jobs, as well as the optimal loading of the magazine(s) of the machine(s), so that the total number of switches is minimized. As formally demonstrated in the literature, the MTSP is a NP-hard problem even when considering the existence of only one manufacturing machine, which could justify the fact that most of the solution methods tackles it heuristically. We thus conclude that its extension to the case of multiples machines is also NP-hard and, therefore, a problem intrinsically difficult to solve. Our goal consists in studying efficient ways to optimize the number of tool switches in environments equipped with flexible manufacturing machines. For that, we address the basic problem, MTSP, and two MTSP variants, in increasing levels of reach, that consider the job sequencing in a set of: (i) identical parallel machines (Identical Parallel Machines problem with Tooling Constraints, IPMTC); and (ii) identical parallel machines inserted in a job shop environment (Job Shop Scheduling Problem with Tooling Constraints, JSSPTC). The main contributions of this thesis are classified according three aspects. First, we pushed the frontier of the MTSP literature by proposing mathematical formulations for IPMTC and JSSPTC. We also developed algorithms based on different solution techniques, such as domain reduction, Path Relinking, Adaptive Large Neighborhood Search and dispatching rules. Finally, to fully evaluate the effectiveness and limits of our methods, three new sets of benchmark instances were generated. We believe that this work contributes positively to the future of research in a broad scenario inside the minimization of tool switches in flexible manufacturing systems.
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Ast, Alexandra. "Control concepts for machine tools with parallel kinematics and flexible bodies." Aachen Shaker, 2008. http://d-nb.info/989104877/04.
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Hardwicke, Alexander. "Performance impacts of profiling multi-threaded applications with flexible analysis tools." Thesis, Malmö högskola, Fakulteten för teknik och samhälle (TS), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-20723.
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Syftet med denna studie var att undersöka hur användningen av profilers påverkade prestandan hos flertrådade applikationer. Studien genomfördes inom ramen för ett projekt med Edument AB som skapat en av de profilers som undersökts i studien. Mer specifikt så syftade studien till att ta reda på vilken ytterligare CPU-tid och RAM som användes och hur mycket längre tid det tog att exekvera en flertrådad applikation vid användningen av profilers. Uppsatsens hypotes var att valet av data som varje profiler registrerade skulle påverka prestanda, och att de som registrerade fler detaljer om applikationen skulle ha störst påverkan.Fem profilers valdes ut med olika egenskaper och funktioner och en testapplikation skrevs för att simulera en flertrådad applikation. En minimalistisk applikation skrevs också och användes för att registrera varje profilers påverkan på RAM och CPU, samt hur testapplikationen påverkades av profilern. Alltså, varje profiler har var för sig blivit profilerad för att försäkra att samma data konsekvent samlats in.Resultaten visade att valet av profiler kan ha stor påverkan på den profilerade applikationens prestanda. Användningen av en av profilerna ledde till att testapplikationen tog 513% så lång tid att exekvera och lade också till 1400% ytterligare RAM-användning. Efter en analys av insamlade data verkade det finnas ett samband mellan de funktioner som varje profiler erbjöd och påverkan på applikationens prestanda vilket stämmer överens med uppsatsens hypotes.The aim of this study was to investigate how the use of profilers impacted the performance of multi-threaded applications. This study was undertaken in the framework of a project for Edument AB, creators of one of the profilers investigated in this study. Specifically, the study aimed to find out what additional overhead can result in profiling multi-threaded applications, with regards to CPU use, memory use, and additional time taken to complete execution. The paper hypothesised that the selection of data that each profiler recorded would impact the performance, with those that recorded a very large amount of detail about the application being profiled would introduce a higher overhead.A selection of five profilers was made, each profiler offering a range of features and functionality, and a test application was written to simulate a multi-threaded application. A very lightweight application, referred to as the monitoring application, was also written which recorded the overhead each profiler used, along with the overhead of the test application and the time taken to run. Essentially, each profiler was itself profiled by the monitoring application, ensuring consistent overhead data was gathered for each profiler.The results of the study showed that the choice of profiler can have a substantial impact on the performance of the application being profiled. One profiler resulted in execution of the test application taking 513% as much time to run, and adding an overhead of 1400% memory use. After analysing this data, there appeared to be a correlation between what features the profilers recorded and the overhead, consistent with the hypothesis put forward at the beginning of the study.