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Ramaswamy, Deepak 1974. "Simulation tools for microelectromechanical systems." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/8625.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2001.Includes bibliographical references (p. 101-104).
In this thesis efficient techniques to solve complex 3-D electromechanical problems are developed. Finite element discretization of complex structures such as the micromirror lead to thousands of internal degrees of freedom. Their mostly rigid motion is exploited leading to a mixed rigid-elastic formulation. This formulation's advantage is apparent when it is incorporated in an efficient coupled domain simulation technique and examples are presented exploring geometry effects on device behavior. Then for system level simulation where full device simulation costs add up we need models with much reduced order with little degradation in accuracy. We describe a model reduction formulation for the electromechanical problem based on implicit techniques which accurately capture the original model behavior.
by Deepak Ramaswamy.
Ph.D.
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Khalid, Ruzelan. "Component-Based Tools for Educational Simulations." Thesis, University of Canterbury. Computer Science and Software Engineering, 2013. http://hdl.handle.net/10092/8540.
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e-Learning is an effective medium for delivering knowledge and skills. In spite of improvements in electronic delivery technologies, e-Learning is still a long way away from offering anything close to efficient and effective learning environments. To improve e-Learning experiences, much literature supports simulation based e-Learning. This thesis begins identifying various types of simulation models and their features that induce experiential learning. We focus on designing and constructing an easy-to-use Discrete Event Simulation (DES) tool for building engaging and informative interactive DES models that allow learners to control the models’ parameters and visualizations through runtime interactions. DES has long been used to support analysis and design of complex systems but its potential to enhance learning has not yet been fully utilized. We first present an application framework and its resulting classes for better structuring DES models. However, importing relevant classes, establishing relationships between their objects and representing lifecycles of various types of active objects in a language that does not support concurrency demand a significant cognitive workload. To improve this situation, we utilize two design patterns to ease model structuring and logic representation (both in time and space) through a drag and drop component approach. The patterns are the Delegation Event Model, used for linking between components and delegating tasks of executing and updating active objects’ lifecycles, and the MVC (Model-View-Controller) pattern, used for connecting the components to their graphical instrumentations and GUIs. Components implementing both design patterns support the process-oriented approach, can easily be tailored to store model states and visualizations, and can be extended to design higher level models through hierarchical simulation development. Evaluating this approach with both teachers and learners using ActionScript as an implementation language in the Flash environment shows that the resulting components not only help model designers with few programming skills to construct DES models, but they also allow learners to conduct various experiments through interactive GUIs and observe the impact of changes to model behaviour through a range of engaging visualizations. Such interactions can motivate learners and make their learning an enjoyable experience.
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Vogelsang, Stefan. "Monitoring Tools File Specification." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-199034.
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This paper describes the format of monitoring data files that are collected for external measuring sites and at laboratory experiments at the Institute for Building Climatology (IBK). The Monitoring Data Files are containers for storing time series or event driven data collected as input for transient heat and moisture transport simulations. Further applications are the documentation of real world behaviour, laboratory experiments or the collection of validation data sets for simulation results ( whole building / energy consumption / HAM ). The article also discusses the application interface towards measurement data verification tools as well as data storage solutions that can be used to archive measurement data files conveniently and efficiently.
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El-Mounayri, Hazim A. "Generic solid modelling based machining process simulation." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/NQ30083.pdf.
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Schalin, Mikael. "Computational tools for simulation of phase transformations." Doctoral thesis, KTH, Materials Science and Engineering, 1999. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-2779.
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A new software package, Thermite, for thermodynamiccalculations and process simulation is developed around theThermo-Calc databank. Thermite is a computational toolbox forequilibrium calculations and simulation of phasetransformations. It provides graphic visualisation and allowsmanipulation of the presented data.
Two types of phase transformations have been implemented inthe software. First, it was used to simulate solidification ofalloys using the Gulliver-Scheil model. Simulations were madewith both Gulliver-Scheil model and with the DICTRA softwareand the predictions were compared with experimentalinformation. The interpretation of experimental cooling curveswas examined in detail and the role of back diffusion in thesolidified material has been considered. It was shown thatcooling curves with respect to time could be calculated fromenthalpy by integrating over the solidified layers.
Secondly, it was used to study the role of phase interfacesfor solid-solid transformations. The Hillert-Sundman treatmentof solute drag has been extended to multi-component systems.Using this extended treatment, the influences of the differentmodel parameters for partitionless transformation wereinvestigated and a comparison was made with earlier work. Theeffect of solute drag on the movement of grain boundaries wasstudied.
A technique was also developed to interface Thermo-Calc withother programs. This technique was used to link the DICTRAsoftware to the Thermite software package. The whole Thermitepackage is strictly organised in independent libraries toenable the substitution of each library. In particular, alibrary called Thermo-Calc C library has been designed tosupply thermodynamic calculations to many differentapplications.
Keywords:thermodynamic calculations, simulation, phasetransformations, equilibrium, solidification, solute drag,massive transformations
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Figueiredo, Sérgio Miguel Calafate de. "Evaluation of network simulation and modelimg tools." Master's thesis, Universidade de Aveiro, 2008. http://hdl.handle.net/10773/1964.
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Mestrado em Engenharia Electrónica e TelecomunicaçõesA crescente globalização da Internet e consequente procura de largura de banda nas redes IP existentes fez emergir a necessidade de um melhor planeamento das redes de telecomunicações. Tendo em vista esse fim foram criadas ferramentas aptas a auxiliar a gestão de redes, como software de monitorização, e em particular os simuladores de redes. Estes permitem a obtenção de resultados preciosos sem a consumo de recursos que a criação de uma testbed real requer. Um desses simuladores é o Opnet Modeler, um software comercial que possibilita a configuração de cenários a vários níveis, como as características dos protocolos, perfis de utilizadores e de mobilidade, ou a estrutura e dimensão da rede. Esta dissertação propôe-se a numa primeira parte a analisar vários aspectos respeitantes à utilização do Opnet Modeler no prisma do gestor de redes, em especial em redes à escala de Campus, explorando algumas das vantagens e lacunas na sua utilização para diversos fins, tais como o design ou restruturação de redes e a análise da qualidade de serviço de diferentes aplicações. Uma componente indispensável à gestão de redes é a previsão de qualidade de serviço. O facto do comportamento do tráfego numa rede variar devido a factores como a alteração do número de utilizadores ou dos seus perfis de tráfego, leva a que seja várias vezes necessário estimar o comportamento da rede sem o perfeito conhecimento desta ou dos seus recursos. O nível de tráfego actualmente desperdiçado devido a uma incorrecta estimativa por parte dos ISP’s da utilização de redes mais complexas representa ao mesmo tempo custos desnecessários e recursos subaproveitados. A procura de um modelo de tráfego que possibilite uma aproximação mais exacta dos parâmetros previstos em relação à realidade leva a que haja uma maior investigação nesta área. Nesta dissertação é testado um framework modelador que se baseia apenas em medições (ou resultados de simulações) de tráfego e correspondentes parâmetros de qualidade de serviço dos pontos de acesso da rede, sem o conhecimento a priori da matriz de tráfego e da topologia da rede, para prever a qualidade de serviço em condições distintas. ABSTRACT: The growing Internet globalization and consequent demand for bandwidth in the existing IP networks lead to the emerging need of a better network telecommunications planning. In order to accomplish that, apt network management tools were created, like monitoring software and network simulators, in particular. These allow the collection of precious results exempt of the resources consumption that the use of a real testbed would require. One of those simulators is Opnet Modeler, commercial software that allows to configure the scenarios at multiple levels, like protocol characteristics, profiles and mobility profiles, or the network size and structure. This dissertation proposes to analyze various aspects related to Opnet Modeler use in a network manager perspective, in particular in Campus scale networks, aiming to explore its advantages and gaps when used for goals such as network design or restructuration and for different services’ QoS analysis. One essential component in network management is QoS prediction. The fact that the network traffic behavior varies due to details like the change in the number of users or their traffic profiles, many times leads to the need of assessing the network behavior without the perfect knowledge of the network or its resources. The currently wasted bandwidth by the ISP’s and network managers due to an incorrect assessment of the utilization in more complex networks represents unnecessary costs and wasted resources. The pretension to obtain a traffic model that allows a more exact approximation of the predicted parameters relatively to the reality lead to a major increase in the research in this area. In this dissertation, the evluation of a modeling framework is performed; that model, based only in traffic measurements (or simulation results) and corresponding QoS parameters at the network access points, that is, without the a priori knowledge of the network’s traffic matrix and topology, is able to predict the network’s QoS for different conditions.
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Gentry, Retha D., Lisa Ousley, and Candice Short. "Innovative Dermatology Tools for Use in Simulation." Digital Commons @ East Tennessee State University, 2019. https://dc.etsu.edu/etsu-works/8373.
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Sentausa, Erwin. "Time course simulation replicability of SBML-supporting biochemical network simulation tools." Thesis, University of Skövde, School of Humanities and Informatics, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-33.
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Background: Modelling and simulation are important tools for understanding biological systems. Numerous modelling and simulation software tools have been developed for integrating knowledge regarding the behaviour of a dynamic biological system described in mathematical form. The Systems Biology Markup Language (SBML) was created as a standard format for exchanging biochemical network models among tools. However, it is not certain yet whether actual usage and exchange of SBML models among the tools of different purpose and interfaces is assessable. Particularly, it is not clear whether dynamic simulations of SBML models using different modelling and simulation packages are replicable.
Results: Time series simulations of published biological models in SBML format are performed using four modelling and simulation tools which support SBML to evaluate whether the tools correctly replicate the simulation results. Some of the tools do not successfully integrate some models. In the time series output of the successful
simulations, there are differences between the tools.
Conclusions: Although SBML is widely supported among biochemical modelling and simulation tools, not all simulators can replicate time-course simulations of SBML models exactly. This incapability of replicating simulation results may harm the peer-review process of biological modelling and simulation activities and should be addressed accordingly, for example by specifying in the SBML model the exact algorithm or simulator used for replicating the simulation result.
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Mallory, Richard Smith. "Tools for explaining complex qualitative simulations /." Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.
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Adourian, Chahe. "Bidirectional integration of geometric and dynamic simulation tools." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=96756.
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Mechanisms to share information from Mechanical Computer Assisted Design (MCAD) to simulation model have been demonstrated using various approaches. However, in all cases the information sharing is unidirectional - from the MCAD to Multi-Body Systems (MBS) simulation - which lacks the bidirectional mapping required in a concurrent engineering context where both models need to develop in parallel while remaining consistent.We present a modelling library and a model mapping that permits and encourages parallel development of the mechanical assembly in both the MBS simulation and MCAD environments while supporting both bidirectional initial full transfer and incremental updates. Furthermore, with the adopted approach and with a careful selection of the simulation language, MCAD parts can be extended with non-mechanical behaviour in the simulation tool.Des mécanismes pour partager l'information entre un modèle CAD et un modèle de simulation ont été démontrés utilisant divers approches. Pourtant, dans tous les cas, le partage d'information était unidirectionnel - allant du modèle CAD vers le modèle de simulation - donc ne possédant pas les qualités bidirectionnelles nécessaires dans le contexte de l'ingénierie collaborative ou les modèles doivent rester consistantes en permanence.Nous présentons notre librairie de modélisation et de transformations entre modèles qui permettent et encouragent le développement parallèle de l'assemblage mécanique dans les deux environnements de simulation de conception. Notre approche supporte le partage et la synchronisation des deux modèles dans les deux sens et de façon incrémentale si nécessaire. En complément, avec l'approche que nous avons adopté, les modèles mécaniques peuvent être associés a des modèles comportementales non mécanique dans l'outil de simulation.
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Rhoads, Russell A. Gilman Scott D. "Wargaming and simulation as tools for CONOPS development /." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Sep%5FRhoads.pdf.
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Thesis (M.S. in Modeling Virtual Environments and Simulations (MOVES))--Naval Postgraduate School, Sept. 2004.Thesis advisor(s): Saverio M. Manago, Thomas W. Lucas. Includes bibliographical references (p. 87-89). Also available online.
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Gilman, Scott D., and Russell A. Rhoads. "Wargaming and simulation as tools for CONOPS development." Thesis, Monterey, California. Naval Postgraduate School, 2004. http://hdl.handle.net/10945/1423.
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Approved for public release; distribution is unlimitedThe purpose of this thesis is to use wargaming and simulation to gain insight into the effective employment of a new Command, Control, Communications, Computers, Intelligence, Surveillance, and Reconnaissance (C4ISR) system, the Adaptive Joint C4ISR Node (AJCN). The AJCN provides the supported commander with several capabilities, to include: range extension, waveform bridging, signal intelligence, electronic warfare, and information operations. Two methods are used to gain insight to the support generation of the concept of operations for the AJCN's employment. The first method is wargaming. The wargaming method utilized a class of NPS students and the JCATS combat simulation model. The wargaming generated insights concerning the AJCN's employment. The second method is the use of a constructive simulation model, POA 2. Insights gained from the two methods include: the need for commanders to differentiate the AJCN and its supporting platform; the need for effective information processing techniques; the importance of maintaining at least two-tiers of AJCN coverage to enhance situational awareness of the supported units.
Major, United States Army
Captain, United States Army
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Zhang, Zhao Kang. "Downhole fluid flow simulation during tripping operations." Thesis, Robert Gordon University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364683.
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Unthank, Gary. "An investigation into logistic centre design tools." Thesis, University of Sunderland, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326329.
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Choi, Hong Fei. "Numerical simulation of atrium fire using two CFD tools." Thesis, University of Macau, 2007. http://umaclib3.umac.mo/record=b1694321.
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Deglaire, Paul. "Analytical Aerodynamic Simulation Tools for Vertical Axis Wind Turbines." Doctoral thesis, Uppsala universitet, Elektricitetslära, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-132073.
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Wind power is a renewable energy source that is today the fastest growing solution to reduce CO2 emissions in the electric energy mix. Upwind horizontal axis wind turbine with three blades has been the preferred technical choice for more than two decades. This horizontal axis concept is today widely leading the market. The current PhD thesis will cover an alternative type of wind turbine with straight blades and rotating along the vertical axis. A brief overview of the main differences between the horizontal and vertical axis concept has been made. However the main focus of this thesis is the aerodynamics of the wind turbine blades. Making aerodynamically efficient turbines starts with efficient blades. Making efficient blades requires a good understanding of the physical phenomena and effective simulations tools to model them. The specific aerodynamics for straight bladed vertical axis turbine flow are reviewed together with the standard aerodynamic simulations tools that have been used in the past by blade and rotor designer. A reasonably fast (regarding computer power) and accurate (regarding comparison with experimental results) simulation method was still lacking in the field prior to the current work. This thesis aims at designing such a method. Analytical methods can be used to model complex flow if the geometry is simple. Therefore, a conformal mapping method is derived to transform any set of section into a set of standard circles. Then analytical procedures are generalized to simulate moving multibody sections in the complex vertical flows and forces experienced by the blades. Finally the fast semi analytical aerodynamic algorithm boosted by fast multipole methods to handle high number of vortices is coupled with a simple structural model of the rotor to investigate potential aeroelastic instabilities. Together with these advanced simulation tools, a standard double multiple streamtube model has been developed and used to design several straight bladed rotor ranging from 2 kW to 20 kW.Felaktigt tryckt som Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 704
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Karlsson, Mattias. "COMPARISON AND EVALUATION OF HARDWARE MODELLING AND SIMULATION TOOLS." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Data- och elektroteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-16734.
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Avionics Division of Saab AB develops advanced electronics that need to be robust and work in harsh environments with for example extreme temperatures and cosmic radiation without any failure. To succeed with this the electronics need to be simulated and tested. Therefore this thesis work is done to strengthen the Avionics Division’s knowledge of hardware modelling and simulation by evaluating the simulation tools LTSpice, PSpice and SystemVision, their functions and capabilities. In this thesis a survey is carried out with help of a questionnaire to study the Avionics Division’s needs for simulation. The survey is underlying an analysis of the analyses that can be performed by the simulation tools for example Sensitivity analysis, Worst Case analysis, Monte Carlo analysis and Parametric Sweep analysis. The different analyses are discussed in the thesis. The questionnaire is also underlying an analysis of the tools LTSpice, PSpice and SystemVision. The result of the analysis is summarized in Table 1. A case study of a circuit simulation in SystemVision, based on an existing circuit used by Avionics Division, is also done within this thesis work. The study is done to evaluate the tool’s usability, to see if it is easy to perform a simulation and if it is easy to find and use suitable models from the model library. The case study describes how a simulation is performed in SystemVision and how an AC analysis of a Butterworth filter is done. A stability and reliability check of the tool is performed as well as a robustness simulation. The analyses were easy to do and the overall impression is that SystemVision is reliable and user friendly structured. In order to check and compare the results of the AC analysis the same analysis is performed using LTSpice. The comparison shows that the results differ. This depending on that the models of the circuit were some what different in LTSpice and SystemVision. The final conclusion is that SystemVision would fit within Avionics Division’s workflow. Using SystemVision demands education of the engineers to secure maximum use of all the advantages of SystemVision.
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Andrew, Steven Paul. "Tools for the simulation and analysis of aerodynamic models." Ohio : Ohio University, 1999. http://www.ohiolink.edu/etd/view.cgi?ohiou1176224995.
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Pongratananukul, Nattorn. "ANALYSIS AND SIMULATION TOOLS FOR SOLAR ARRAY POWER SYSTEMS." Doctoral diss., University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2565.
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This dissertation presents simulation tools developed specifically for the design of solar array power systems. Contributions are made in several aspects of the system design phases, including solar source modeling, system simulation, and controller verification. A tool to automate the study of solar array configurations using general purpose circuit simulators has been developed based on the modeling of individual solar cells. Hierarchical structure of solar cell elements, including semiconductor properties, allows simulation of electrical properties as well as the evaluation of the impact of environmental conditions. A second developed tool provides a co-simulation platform with the capability to verify the performance of an actual digital controller implemented in programmable hardware such as a DSP processor, while the entire solar array including the DC-DC power converter is modeled in software algorithms running on a computer. This "virtual plant" allows developing and debugging code for the digital controller, and also to improve the control algorithm. One important task in solar arrays is to track the maximum power point on the array in order to maximize the power that can be delivered. Digital controllers implemented with programmable processors are particularly attractive for this task because sophisticated tracking algorithms can be implemented and revised when needed to optimize their performance. The proposed co-simulation tools are thus very valuable in developing and optimizing the control algorithm, before the system is built. Examples that demonstrate the effectiveness of the proposed methodologies are presented. The proposed simulation tools are also valuable in the design of multi-channel arrays. In the specific system that we have designed and tested, the control algorithm is implemented on a single digital signal processor. In each of the channels the maximum power point is tracked individually. In the prototype we built, off-the-shelf commercial DC-DC converters were utilized. At the end, the overall performance of the entire system was evaluated using solar array simulators capable of simulating various I-V characteristics, and also by using an electronic load. Experimental results are presented.Ph.D.
Department of Electrical and Computer Engineering
Engineering and Computer Science
Electrical Engineering
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Corona, Thomas Joseph. "Tools for electromagnetic field simulation in the KATRIN experiment." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/53239.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Physics, 2009.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 130-135).
The Karlsruhe Tritium Neutrino (KATRIN) experiment is a tritium beta decay experiment designed to make a direct, model independent measurement of the electron neutrino mass. To accomplish this task, the experiment employs precisely defined electric and magnetic fields for particle transport and mass spectroscopy. In order to simulate particle trajectories in the experiment, it is essential to have methods for calculating these fields quickly and accurately. The application of the methods of direct elliptic integral calculation, zonal harmonic expansion and interpolation from an adaptive-refinement field mesh is described within the object-oriented KatrinField framework, as well as an analysis of their comparative strengths and weaknesses in reproducing the electromagnetic fields found in KATRIN.
by Thomas Joseph Corona.
S.M.
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Roy, Scott Allen. "Simulation tools for the analysis of single electronic systems." Thesis, University of Glasgow, 1994. http://theses.gla.ac.uk/7655/.
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Developments in theory and experiment have raised the prospect of an electronic technology based on the discrete nature of electron tunnelling through a potential barrier. This thesis deals with novel design and analysis tools developed to study such systems. Possible devices include those constructed from ultrasmall normal tunnelling junctions. These exhibit charging effects including the Coulomb blockade and correlated electron tunnelling. They allow transistor-like control of the transfer of single carriers, and present the prospect of digital systems operating at the information theoretic limit. As such, they are often referred to as single electronic devices. Single electronic devices exhibit self quantising logic and good structural tolerance. Their speed, immunity to thermal noise, and operating voltage all scale beneficially with junction capacitance. For ultrasmall junctions the possibility of room temperature operation at sub picosecond timescales seems feasible. However, they are sensitive to external charge; whether from trapping-detrapping events, externally gated potentials, or system cross-talk. Quantum effects such as charge macroscopic quantum tunnelling may degrade performance. Finally, any practical system will be complex and spatially extended (amplifying the above problems), and prone to fabrication imperfection. This summarises why new design and analysis tools are required. Simulation tools are developed, concentrating on the basic building blocks of single electronic systems; the tunnelling junction array and gated turnstile device. Three main points are considered: the best method of estimating capacitance values from physical system geometry; the mathematical model which should represent electron tunnelling based on this data; application of this model to the investigation of single electronic systems.
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Zhong, Shishengxiong, and Jinzhe Zhao. "A comparison of simulation tools for supply chain management." Thesis, Linnéuniversitetet, Institutionen för datavetenskap och medieteknik (DM), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-97103.
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This report provides a comparison of discrete-event simulation tools for supply chain models. We use different simulation tools (Arena and AnyLogic) to analyze and inspect the C14 supply chain management benchmark, as well as, a real-world business supply chain model that is provided by Vantai company in China. In this study, we consider different aspects of these simulation tools (such as, the capability of discrete-event simulation, visualization, simulation efficiency and accuracy, and debugging) to explore their advantages and disadvantages. We hope that our simulation results will have a positive impact on the supply chain management of the companies that provided us with data for this study; furthermore, the comparison results may be useful to developers and researchers in future simulation studies.
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Owen, Christopher. "Selection of simulation tools for improving supply chain performance." Thesis, Aston University, 2013. http://publications.aston.ac.uk/20896/.
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Simulation is an effective method for improving supply chain performance. However, there is limited advice available to assist practitioners in selecting the most appropriate method for a given problem. Much of the advice that does exist relies on custom and practice rather than a rigorous conceptual or empirical analysis. An analysis of the different modelling techniques applied in the supply chain domain was conducted, and the three main approaches to simulation used were identified; these are System Dynamics (SD), Discrete Event Simulation (DES) and Agent Based Modelling (ABM). This research has examined these approaches in two stages. Firstly, a first principles analysis was carried out in order to challenge the received wisdom about their strengths and weaknesses and a series of propositions were developed from this initial analysis. The second stage was to use the case study approach to test these propositions and to provide further empirical evidence to support their comparison. The contributions of this research are both in terms of knowledge and practice. In terms of knowledge, this research is the first holistic cross paradigm comparison of the three main approaches in the supply chain domain. Case studies have involved building ‘back to back’ models of the same supply chain problem using SD and a discrete approach (either DES or ABM). This has led to contributions concerning the limitations of applying SD to operational problem types. SD has also been found to have risks when applied to strategic and policy problems. Discrete methods have been found to have potential for exploring strategic problem types. It has been found that discrete simulation methods can model material and information feedback successfully. Further insights have been gained into the relationship between modelling purpose and modelling approach. In terms of practice, the findings have been summarised in the form of a framework linking modelling purpose, problem characteristics and simulation approach.
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Claffey, Douglas J. "ADVANCED SIMULATION TOOLS TO MODEL AND ANALYZE OPERATIONAL ENVIRONMENTS." International Foundation for Telemetering, 1999. http://hdl.handle.net/10150/606813.
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International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, NevadaAdvances in high-level architectures in both hardware and software now allow 3D software modeling and interactive simulation to be done from the desktop computer. This paper will address the increasing demand for 3D software modeling and simulation applications throughout the aerospace industry, what kinds of tools are currently available, how operational data is being used in real-world applications, and how to couple real-time data with terrain models and simulation tools to model and analyze operational environments. The following specific areas will be addressed: · The creation of real-world environments by merging virtual objects and ground data with interactive simulation and advanced graphics. · Recent advances in software modeling and simulation tools, which mirror general industry trends. · The ongoing effort to establish standards for modeling and simulation applications throughout the aerospace industry. · Examples of applications using high-level architecture-enabling technology like the visual display of detailed terrain data, drag-and-drop imagery, the enhancement of graphical performance without compromising the quality of rendered data, and expanded support for raster file format images.
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Hsu, Chia-Jui. "Dataflow integration and simulation techniques for DSP system design tools." College Park, Md. : University of Maryland, 2007. http://hdl.handle.net/1903/6901.
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Thesis (Ph. D.) -- University of Maryland, College Park, 2007.Thesis research directed by: Electrical Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Zhang, Lei. "Modeling and Verification of Simulation tools for Carburizing and Carbonitriding." Digital WPI, 2017. https://digitalcommons.wpi.edu/etd-dissertations/484.
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"The CHTE surface hardening simulation tools, CarboNitrideTool© and CarbTool© have been enhanced to improve the accuracy of the simulation and to predict the microstructure and microhardness profiles after the heat treatment process. These tools can be used for the prediction of both gas and low pressure carburizing processes. The steel alloys in the data base include 10XX, 48XX, 51XX, 86XX, 93XX and Pyrowear 53. They have been used by CHTE members to design efficient carburizing cycles to maximum the profit by controlling the cost and time. In the current software, the model has successfully predicted the carbon concentration profiles for gas carburizing process and many low pressure carburizing processes. In some case, the simulation toll may not work well with the low pressure carburizing process, especially with AISI 9310 alloy. In the previous simulation, a constant carbon flux boundary condition was used. However, it has been experimentally proven that the flux is a function of time. The high carbon potential may cause soot and carbides at the outer edge. The soot and carbides will impede the diffusion of carbon during the low pressure carburizing process. The constant carbon flux cannot be appropriately used as the boundary condition. An improved model for the process is proposed. In the modeling, carbon potential and mass transfer coefficient are calculated and used as the boundary condition. CarbonitrideToolⒸ has been developed for the prediction of both carbon and nitrogen profiles for carbonitriding process. The microstructure and hardness profile is also needed by the industry. The nitrogen is an austenite stabilizer which result in high amount of retained austenite (RA). RA plays important role in the hardness. The model has been developed to predict the Martensite start temperature (Ms) which can be used for RA prediction. Mixture rule is used then to predict the hardness profiles. Experiments has been conducted to verify the simulation. The hardness profile is also predicted for tempered carburized alloys. Hollomon-Jaffe equation was used. A matrix of tempering experiments are conducted to study the Hollomon Jaffe parameter for AISI 8620 and AISI 9310 alloy. Constant C value is calculated with a new mathematical method. With the calculation result, the hardness profile can be predicted with input of tempering time and temperature. Case depth and surface hardness are important properties for carburized steel that must be well controlled. The traditional testing is usually destructive. Samples are sectioned and measured by either OES or microhardness tester. It is time consuming and can only be applied on sampled parts. The heat treating industry needs a physics based, verified simulation tool for surface hardening processes to accurately predict concentration profiles, microstructure and microhardness profiles. There is also a need for non-destructive measurement tool to accurately determine the surface hardness and case depth. Magnetic Barkhausen Noise (MBN) is one of the promising way to test the case depth and hardness. MBN measures the pulses generating by the interaction between magnetic domain walls in the ferromagnetic material and the pinning sites such as carbides, impurities and dislocation. These signals are analyzed to evaluate the properties of the carburized steel. "
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Kumar, Yogesh. "Study of Power and Renewable Systems Modeling and Simulation Tools." University of Toledo / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1449868982.
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San, Jose Angel. "Analysis, design, implementation and evaluation of graphical design tool to develop discrete event simulation models using event graphs and SIMKIT." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2001. http://handle.dtic.mil/100.2/ADA397405.
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Thesis (M.S. in Operations Research) Naval Postgraduate School, Sept. 2001.Thesis advisor(s): Buss, Arnold; Miller, Nita. "September 2001." Includes bibliographical references (p. 109-110). Also available in print.
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Scott, Jessica Stacy. "GPU programming for real-time watercolor simulation." Thesis, Texas A&M University, 2004. http://hdl.handle.net/1969.1/1572.
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This thesis presents a method for combining GPU programming with traditional programming to create a fluid simulation based watercolor tool for artists. This application provides a graphical interface and a canvas upon which artists can create simulated watercolors in real time. The GPU, or Graphics Processing Unit, is an effcient and highly parallel processor located on the graphics card of a computer; GPU programming is touted as a way to improve performance in graphics and nongraphics applications. The effectiveness of this method in speeding up large, general purpose programs, however, is found here to be disappointing. In a small application with minimal CPU/GPU interaction, theoretical speedups of 10 times maybe achieved, but with the limitations of communication speed between the GPU and the CPU, gains are slight when this method is used in conjunction with traditional programming.
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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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Molenaar, Robert. "Design and implementation of biosystem control and tools for biosystem simulation." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0017/NQ44519.pdf.
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Hasan, Syed Sharjeel Ul, and Shabbir Ahmed Khan. "Perceptions of students who participated in business simulation at Umeå School of Business, Sweden : A model for educational simulations." Thesis, Umeå universitet, Handelshögskolan vid Umeå universitet, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-46462.
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Purpose: The goal of this study is to emphasize the use of business simulation as a learning tool in educational institutions. For instance, the two master’s programs (marketing & entrepreneurship, provided by Umeå Business School at master’s level), comprised of four core courses each, but only one module out the four provided utilized simulation for learning purpose. Generally self study, class lectures and case studies are used as the main pedagogy tools in the class room setting. In case of Umeå Business School, the use of simulations and gaming was rather limited in Umea School of Business (USBE) despite the fact that simulations are used to the point of saturation in American universities. This research is focused towards exploring the perceptions of students who undertook a business simulation at Umeå Business School, Sweden. Furthermore, it also provides a model for an effective simulation from educational point of view. Method: Hypotheses were developed to investigate the perceptions held by the students at USBE regarding their perceived effectiveness of simulation as a learning tool. A deductive approach was followed by using theories and scientific research by which hypotheses were generated and tested for answering the literature gaps. Quantitative research strategy was used and questionnaires were sent only to qualified respondents (those students of USBE who had already taken simulation at least once in any modules of their study tenure). Hypotheses were generated to find out correlations between the variables and tested through Pearson coefficient using SPSS testing methods. Findings/conclusion: The findings revealed that students consider simulation the most learning tool compared to others. Simulation is considered practical learning, learning through a gaming approach, an exercise that replicates realistic environment in class room. It provides an enjoyable way of learning and the retention of learnt concept is in high to medium range. Empirical findings show that there is a positive correlation between the variable students who would like to use simulation again with the variable that students will register a course which provides simulation. There is a strong positive correlation among variable of perceiving simulation as exciting and variable perceiving it as a fun way of learning. Positive correlation exists among variables of being excited to know of simulation in a course and variable of considering simulation being a learning experience. Lastly we found that there is positive and highest correlation in perception of students regarding likeness and learning with regards to simulation. This means that compared to other tools there is more likeness of simulation amongst students and they perceive it as most learning tool compared to class lectures, guest lectures, self study and group discussions. The study concluded with providing a basic model of an effective simulation which was developed in line with literature review and empirical findings from this research
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Jeppsson, Johan. "Simulation of Phase Transformations and coarsening : Computational tools for alloy development." Doctoral thesis, KTH, Metallografi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-31454.
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The final properties of an alloy are highly interlaced with its microstructure. It is therefore essential to control the evolution of the microstructure of the material during the fabrication process. Nowadays, materials design involves an increasing part of computational design to complement the traditional experimental trial and error approach. Such simulations of the process can decrease the number of material prototypes and shorten the development time for new alloys. In this thesis several microstructure models, aimed for process design, have been suggested. The ambition has been to develop physically based models that are capable to represent the evolution of hundreds of grain or particle sizes, where the models should be possible to run on a standard computer with simulation times less than one day. To achieve this goal, simplified approaches have been suggested, which are accurate enough for the growth rate of grains and particles. The microstructure models have all in common that size distributions of grains or particles are simulated with mean-field approaches. Several of the models also utilize composition and temperature dependent thermodynamic and kinetic properties continually throughout the simulations. These properties have been calculated with programming interfaces to Thermo-Calc and DICTRA together with appropriate thermodynamic and kinetic databases. The materials that have been considered in the present thesis are low alloyed steels, aluminium alloys and cemented carbides. The models are however generic in the sense that all materials can be handled if appropriate thermodynamic, kinetic and property databases exist for the alloy.QC 20110316
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Pei, Dekun. "Development of simulation tools, control strategies, and a hybrid vehicle prototype." Thesis, Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45904.
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This thesis (1) reports the development of simulation tools and control strategies for optimizing hybrid electric vehicle (HEV) energy management, and (2) reports the design and testing of a hydraulic hybrid school bus (HHB) prototype. A hybrid vehicle is one that combines two or more energy sources for use in vehicle propulsion. Hybrid electric vehicles have become popular in the consumer market due to their greatly improved fuel economy over conventional vehicles. The control strategy of an HEV has a paramount effect on its fuel economy performance. In this thesis, backward-looking and forward-looking simulations of three HEV architectures (parallel, power-split and 2-mode power-split) are developed. The Equivalent Cost Minimization Strategy (ECMS), which weights electrical power as an equivalent fuel usage, is then studied in great detail and improvements are suggested. Specifically, the robustness of an ECMS controller is improved by linking the equivalence factor to dynamic programming and then further tailoring its functional form. High-fidelity vehicle simulations over multiple drive-cycles are performed to measure the improved performance of the new ECMS controller, and to show its potential for online application.
While HEVs are prominent in the consumer market and studied extensively in current literature, hydraulic hybrid vehicles (HHVs) only exist as heavy utility vehicle prototypes. The second half of this thesis reports design, construction, and testing of a hydraulic hybrid school bus prototype. Design considerations, simulation results, and preliminary testing results are reported, which indicate the strong potential for hydraulic hybrids to improve fuel economy in the school bus vehicle segment.
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Bolinger, Roman Wilhelm. "The deployment of digital simulation tools to verify cyclic voltammetry experiments /." Zürich, 2000. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=13637.
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Zou, Xi. "Simulation tools for biomechanical applications with PGD-based reduced order models." Doctoral thesis, Universitat Politècnica de Catalunya, 2018. http://hdl.handle.net/10803/481988.
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Numerical simulation tools are generally used in all modern engineering fields, especially those having difficulties in performing large number of practical experiments, such as biomechanics. Among the computational methods, Finite Element (FE) is an essential tool. Nowadays, the fast-growing computational techniques, from the upgrading hardware to the emerging of novel algorithm, have already enabled extensive applications in biomechanics. For applications that require fast response and/or multiple queries, Reduced Order Modelling (ROM) methods have been developed based on existing methods such as FE, and have eventually enabled real-time numerical simulation for a large variety of engineering problems.
In this thesis, several novel computational techniques are developed to explore the capability of Proper Generalised Decomposition (PGD), which is an important approach of ROM. To assess the usability of the PGD-based ROM for biomechanical applications, a real human femur bone is chosen to study its mechanical behaviour as an example. Standard image-based modelling procedure in biomechanics is performed to create an FE model which is then validated with in vitro experimental results.
As a basis of this work, the medical image processing has to be performed, in order to generate an available FE model. This model is validated according to data collected from a previously performed \textit{in vitro} experimental test. The full procedure of image-based model generation and the validation of generated model is described in Chapter 2.
As a major objective of this thesis, a non-intrusive scheme for the PGD framework is developed in Chapter 3. It is implemented using in-house developed Matlab (Mathworks, USA) code to conduct the PGD work flow, and calling Abaqus as an external solver for devised fictitious mechanical problems.
The transformation of data from computed tomography (CT) image set to FE model including inhomogeneous material properties is subjected to some physical constraints, and when applying the load, there are also geometric constraints limiting the locations where load could be applied. These constraints will lead to a constrained parameter space, which possibly has difficulty to be separated in a Cartesian fashion. Therefore, a novel strategy to separate the parameters in a collective manner is proposed in Chapter 4.
Chapter 5 details a comprehensive application in biomechanics, the methodologies proposed in Chapter 3 and 4 are applied on the practical model generated in Chapter 2. As a typical application of the PGD vademecum, a material property identification problem is discussed. Further PGD vademecum is generated using the identified material properties with variable loading locations, and with this vademecum, real-time mechanical response of the femur is available.
In addition, for the purpose of extending the methodologies to orthotropic materials, which is commonly used in biomechanics, in Chapter 6 another linear elastic model is investigated with the non-intrusive PGD scheme. Nowadays, isogeometric analysis (IGA) is a very popular tool in computational mechanics. It is appealing to take advantage of non-uniform rational B-splines (NURBS) to discretise the model. For PGD, using B-splines for the discretisation of the parameter space could improve the quality of vademecum, especially for problems involving sensitivities with respect to the parameters during the online computations.
It is important and necessary to extend the PGD framework to nonlinear solid mechanics, because most biological soft tissues have been observed nonlinear mechanical behaviours. Consequently, in Chapter 7 we have developed a PGD framework for the St.Venant-Kirchhoff constitutive model using the Picard linearisation which is consistent with the fixed-point iteration algorithm commonly used in PGD.
In Chapter 8, conclusive remarks are addressed as well as forecasts of possible future works.
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Delalic, Berina. "Improved control of the consumer substations by using dynamic simulation tools." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for energi- og prosessteknikk, 2014. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-27131.
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Simulation models are becoming important engineering tool that helps in design and adjustment of physical systems. This paper shows application of Modelica programing language through Dymola simulation environment in analysis and discussion on control system in district heating substation. As a central component of heating substation, the model of plate heat exchanger water-to-water was created and implemented in Modelica/Dymola. Verification of that model was done by measurements performed at Laboratory of Department of energy and Process Engineering, Norwegian University of Science and Technology. Beside of the heat exchanger model, the heat substation model was completed using components from Buildings library developed at Lawrence Berkley National Laboratory. Afterwards, the substation model was integrated in system of four buildings connected to the district heating network in order to show potentials for lowering supply and return water temperature. It has been proven to be very promising, with benefits such as opportunity for low temperature heat sources and reducing the heat losses in district heating network.This assignment is realised as a part of the collaborative project Sustainable Energy and Environment in Western Balkans that aims to develop and establish five new internationally recognized MSc study programs for the field of Sustainable Energy and Environment, one at each of the five collaborating universities in three different Western Balkan countries. The project is funded through the Norwegian Programme in Higher Education, Research and Development in the Western Balkans, Programme 3: Energy Sector (HERD Energy) for the period 2011-2013.
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Atyia, Thamir Hassan. "General simulation and design tools for control of electro-mechanical systems." Thesis, University of Newcastle Upon Tyne, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.273364.
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Seehusen, Ashley Elizabeth. "Haptic information in minimally invasive surgery tools for use in simulation." Thesis, University of Bristol, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.247222.
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Alici, Semra. "Dynamic data reconciliation using process simulation software and model identification tools." Access restricted to users with UT Austin EID Full text (PDF) from UMI/Dissertation Abstracts International, 2001. http://wwwlib.umi.com/cr/utexas/fullcit?p3025133.
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Granados, Martinez Alejandro. "Haptics-based simulation tools for teaching and learning digital rectal examinations." Thesis, Imperial College London, 2015. http://hdl.handle.net/10044/1/61896.
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Anorectal and prostate abnormalities are commonly diagnosed via Digital Rectal Examinations (DRE). DRE is challenging to learn as opportunities for practice are limited, it is hard to standardise, there is a lack of feedback and ineffective assessment since visual cues are minimal, and there is vague information as to what constitutes adequate performance. Traditionally, trainees learn initially on plastic benchtop models and on patients later on. However, models are reported to have severe limitations and awareness of ethical issues has curtailed training opportunities. In order to overcome these limitations, a quantitative approach to better understand DREs via a visualization and analysis framework based on position and pressure sensors is presented, together with a series of progressive haptics-enabled learning tools for knowledge acquisition, procedural skills rehearsal and confidence development that aim to fill the existing gap in traditional teaching methods. These tools allow a trainee to literally see-through whilst practicing on benchtop models, visualise anatomical variability of MRI-scanned healthy volunteers, playback of expert performance, execute a series of Cognitive Task Analysis-based steps, rehearse procedural skills via haptics and deformation modelling of patient-specific anatomy, provide formative and summative feedback, and build up communication skills on a hybrid simulator. Experimental studies to validate the visualisation and analysis framework on both benchtop models and real subjects, and to quantify performance of experts from different specialties are presented. Results of evaluation studies with experts to validate the feedback tool and the haptics-based simulator are discussed, and a pre-evaluation study related to the learning tools with medical students is presented. The proposed quantitative analysis has the potential for enhancing the understanding of DRE, and thus to improve learning. The presented body of knowledge, together with the input from the various clinical specialties that routinely perform DRE, relevant educational theory and innovative technology design, constitute an important contribution that may help overcome limitations of current DRE training methods.
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Adiwijaya, Bambang Senoaji. "Simulation and optimization tools to study design principles of biological networks." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/37973.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Biological Engineering Division, 2006.Includes bibliographical references.
Recent studies have developed preliminary wiring diagrams for a number of important biological networks. However, the design principles governing the construction and operation of these networks remain mostly unknown. To discover design principles in these networks, we investigated and developed a set of computational tools described below. First, we looked into the application of optimization techniques to explore network topology, parameterization, or both, and to evaluate relative fitness of networks operational strategies. In particular, we studied the ability of an enzymatic cycle to produce dynamic properties such as responsiveness and transient noise filtering. We discovered that non-linearity of the enzymatic cycle allows more effective filtering of transient noise. Furthermore, we found that networks with multiple activation steps, despite being less responsive, are better in filtering transient noise. Second, we explored a method to construct compact models of signal transduction networks based on a protein-domain network representation. This method generates models whose number of species, in the worst case, scales quadratically to the number of protein-domain sites and modification states, a tremendous saving over the combinatorial scaling in the more standard mass-action model was estimated to consist of more that 10⁷ species and was too large to simulate; however, a simplified model consists of only 132 state variables and produced intuitive behavior. The resulting models were utilized to study the roles of a scaffold protein and of a shared binding domain to pathway functions.
by Bambang Senoaji Adiwijaya.
Ph.D.
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Deora, Gautam Krishnakumar. "Simulation and Mathematical Tools for Performance Analysis of Low-Complexity Receivers." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/31127.
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In recent years, research on the design and performance evaluation of suboptimal receiver implementations has received considerable attention owing to complexity in the realization of the optimal receiver algorithms over wireless channels. This thesis addresses the effects of using reduced complexity receivers for the Satellite Digital Audio Radio (SDAR), Code Division Multiple Access (CDMA) and UltraWideband (UWB) communications technologies.
A graphical-user-interface simulation tool has been developed to predict the link reliability performance of the SDAR services in the continental United States. Feasibility study of receiving both satellite and terrestrial repeater signals using a selection diversity (single antenna) receiver has also been performed.
The thesis also develops a general mathematical framework for studying the efficacy of a sub-optimal generalized selection combining (GSC) diversity receiver over generalized fading channel models. The GSC receiver adaptively combines a subset of M diversity paths with the highest instantaneous signal-to-noise ratios (SNR) out of the total L available diversity paths. The analytical framework is applicable for rake receiver designs in CDMA and UWB communications.Master of Science
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Kaufman, Andrew. "Interactive tools for biomechanical modeling and realistic animation." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/1492.
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We describe a semi-automatic technique for modeling and animating complex musculoskeletal systems using a strand based muscle model. Using our interactive tools, we are able to generate the motion of tendons and muscles under the skin of a traditionally animated character. This is achieved by integrating the traditional animation pipeline with a biomechanical simulator capable of dynamic simulation with complex routing constraints on muscles and tendons. We integrate our musculoskeletal modeling and animation toolkit into a professional 3D production environment, thereby enabling artists and scientists to create complex musculoskeletal systems that were previously inaccessible to them. We demonstrate the applications of our tools to the visual effects industry with several animations of the human hand and applications to the biomechanics community with a novel model of the human shoulder.
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Wikström, Jonas. "3D Model of Fuel Tank for System Simulation : A methodology for combining CAD models with simulation tools." Thesis, Linköpings universitet, Maskinkonstruktion, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-71370.
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Engineering aircraft systems is a complex task. Therefore models and computer simulations are needed to test functions and behaviors of non existing systems, reduce testing time and cost, reduce the risk involved and to detect problems early which reduce the amount of implementation errors. At the section Vehicle Simulation and Thermal Analysis at Saab Aeronautics in Linköping every basic aircraft system is designed and simulated, for example the fuel system. Currently 2-dimensional rectangular blocks are used in the simulation model to represent the fuel tanks. However, this is too simplistic to allow a more detailed analysis. The model needs to be extended with a more complex description of the tank geometry in order to get a more accurate model. This report explains the different steps in the developed methodology for combining 3-dimensional geometry models of any fuel tank created in CATIA with dynamic simulation of the fuel system in Dymola. The new 3-dimensional representation of the tank in Dymola should be able to calculate fuel surface location during simulation of a maneuvering aircraft. The first step of the methodology is to create a solid model of the fuel contents in the tank. Then the area of validity for the model has to be specified, in this step all possible orientations of the fuel acceleration vector within the area of validity is generated. All these orientations are used in the automated volume analysis in CATIA. For each orientation CATIA splits the fuel body in a specified number of volumes and records the volume, the location of the fuel surface and the location of the center of gravity. This recorded data is then approximated with the use of radial basis functions implemented in MATLAB. In MATLAB a surrogate model is created which are then implemented in Dymola. In this way any fuel surface location and center of gravity can be calculated in an efficient way based on the orientation of the fuel acceleration vector and the amount of fuel. The new 3-dimensional tank model is simulated in Dymola and the results are compared with measures from the model in CATIA and with the results from the simulation of the old 2-dimensional tank model. The results shows that the 3-dimensional tank gives a better approximation of reality and that there is a big improvement compared with the 2-dimensional tank model. The downside is that it takes approximately 24 hours to develop this model.Att utveckla ett nytt flygplanssystem är en väldigt komplicerad arbetsuppgift. Därför används modeller och simuleringar för att testa icke befintliga system, minska utvecklingstiden och kostnaderna, begränsa riskerna samt upptäcka problem tidigt och på så sätt minska andelen implementerade fel. Vid sektionen Vehicle Simulation and Thermal Analysis på Saab Aeronautics i Linköping designas och simuleras varje grundflygplanssystem, ett av dessa system är bränslesystemet. För närvarande används 2-dimensionella rätblock i simuleringsmodellen för att representera bränsletankarna, vilket är en väldigt grov approximation. För att kunna utföra mer detaljerade analyser behöver modellerna utökas med en bättre geometrisk beskrivning av bränsletankarna. Denna rapport går igenom de olika stegen i den framtagna metodiken för att kombinera 3- dimensionella tankmodeller skapade i CATIA med dynamisk simulering av bränslesystemet i Dymola. Den nya 3-dimensionella representationen av en tank i Dymola bör kunna beräkna bränsleytans läge under en simulering av ett manövrerande flygplan. Första steget i metodiken är att skapa en solid modell av bränslet som finns i tanken. Därefter specificeras modellens giltighetsområde och alla tänkbara riktningar hos accelerationsvektorn som påverkar bränslet genereras, dessa används sedan i den automatiserade volymanalysen i CATIA. För varje riktning delar CATIA upp bränslemodellen i ett bestämt antal delar och registrerar volymen, bränsleytans läge samt tyngdpunktens position för varje del. Med hjälp av radiala basfunktioner som har implementerats i MATLAB approximeras dessa data och en surrogatmodell tas fram, denna implementeras sedan i Dymola. På så sätt kan bränsleytans och tyngdpunktens läge beräknas på ett effektivt sätt, baserat på riktningen hos bränslets accelerationsvektor samt mängden bränsle i tanken. Den nya 3-dimensionella tankmodellen simuleras i Dymola och resultaten jämförs med mätningar utförda i CATIA samt med resultaten från den gamla simuleringsmodellen. Resultaten visar att den 3-dimensionella tankmodellen ger en mycket bättre representation av verkligheten och att det är en stor förbättring jämfört med den 2-dimensionella representationen. Nackdelen är att det tar ungefär 24 timmar att få fram denna 3-dimensionella representation.
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Summad, Emad. "A Monte-Carlo approach to tool selection for sheet metal punching and nibbling." Thesis, Durham University, 2001. http://etheses.dur.ac.uk/4137/.
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Selecting the best set of tools to produce certain geometrical shapes/features in sheet metal punching is one of the problems that has a great effect on product development time, cost and achieved quality. The trend nowadays is, where at all possible, to limit design to the use of standard tools. Such an option makes the problem of selecting the appropriate set of tools even more complex, especially when considering that sheet metal features can have a wide range of complex shapes. Another dimension of complexity is limited tool rack capacity. Thus, an inappropriate tool selection strategy will lead to punching inefficiency and may require frequent stopping of the machine and replacing the required tools, which is a rather expensive and time consuming exercise. This work demonstrates that the problem of selecting the best set of tools is actually a process of searching an explosive decision tree. The difficulty in searching such types of decision trees is that intermediate decisions do not necessarily reflect the total cost implication of carrying out such a decision. A new approach to solve such a complex optimisation problem using the Monte Carlo Simulation Methods has been introduced in this thesis. The aim of the present work was to establish the use of Monte Carlo methods as an "assumptions or rule free" baseline or benchmark for the assessment of search strategies. A number of case studies are given, where the feasibility of Monte Carlo Simulation Methods as an efficient and viable method to optimise such a complex optimisation problem is demonstrated. The use of a Monte Carlo approach for selecting the best set of punching tools, showed an interesting point, that is, the effect of dominant "one-to-one" feature/tool matches on the efficiency of the search. This naturally led on to the need of a search methodology that will be more efficient than the application of the Monte Carlo method alone. This thesis presents some interesting speculations for a hybrid approach to tool selection to achieve a better solution than the use of the Monte Carlo method alone to achieve the optimum solution in a shorter time.
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Ihlenfeldt, Steffen, Christian Brecher, Matthias Putz, and David Billington. "Conference on Thermal Issues in Machine Tools: Proceedings." Verlag Wissenschaftliche Scripten, 2018. https://tud.qucosa.de/id/qucosa%3A32644.
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Inhomogeneous and changing temperature distributions in machine tools lead to sometimes considerable quality problems in the manufacturing process. In addition, the switching on and off of aggregates, for example, leads to further fluctuations in the temperature field of machine tools. More than 100 specialists discussed these and other topics from the field of thermal research at the 1st Conference on Termal Issues in Machine Tools in Dresden from 22 to 23 March.:Efficient modelling and computation of structure-variable thermal behavior of machine tools
S. Schroeder, A. Galant, B. Kauschinger, M. Beitelschmidt
Parameter identification software for various thermal model types
B. Hensel, S. Schroeder, K. Kabitzsch
Minimising thermal error issues on turning centre
M. Mareš, O. Horejš, J. Hornych
The methods for controlled thermal deformations in machine tools
A. P. Kuznetsov, H.-J. Koriath, A.O. Dorozhko
Efficient FE-modelling of the thermo-elastic behaviour of a machine tool slide in lightweight design
C. Peukert, J. Müller, M. Merx, A. Galant, A. Fickert, B. Zhou, S. Städtler, S. Ihlenfeldt, M. Beitelschmidt
Development of a dynamic model for simulation of a thermoelectric self-cooling system for linear direct drives in machine tools
E. Uhlmann, L. Prasol, S.Thom, S. Salein, R. Wiese
System modelling and control concepts of different cooling system structures for machine tools
J. Popken, L. Shabi, J. Weber, J. Weber
The electric drive as a thermo-energetic black box
S. Winkler, R. Werner
Thermal error compensation on linear direct drive based on latent heat storage
I. Voigt, S. Winkler, R. Werner, A. Bucht, W.-G. Drossel
Industrial relevance and causes of thermal issues in machine tools
M. Putz, C. Richter, J. Regel, M. Bräunig
Clustering by optimal subsets to describe environment interdependencies
J. Glänzel, R. Unger, S. Ihlenfeldt
Using meta models for enclosures in machine tools
F. Pavliček, D. P. Pamies, J. Mayr, S. Züst, P. Blaser, P. Hernández-Becerro, K. Wegener
Model order reduction of thermal models of machine tools with varying boundary conditions
P. Hernández-Becerro, J. Mayr, P. Blaser, F. Pavliček, K. Wegener
Effectiveness of modelling the thermal behaviour of the ball screw unit with moving heat sources taken into account
J. Jedrzejewski, Z. Kowal, W. Kwasny, Z. Winiarski
Analyzing and optimizing the fluidic tempering of machine tool frames
A. Hellmich, J. Glänzel, A. Pierer
Thermo-mechanical interactions in hot stamping
L. Penter, N. Pierschel
Experimental analysis of the heat flux into the grinding tool in creep feed grinding with CBN abrasives
C. Wrobel, D. Trauth, P. Mattfeld, F. Klocke
Development of multidimensional characteristic diagrams for the real-time correction of thermally caused TCP-displacements in precise machining
M. Putz, C. Oppermann, M. Bräunig
Measurement of near cutting edge temperatures in the single point diamond turning process
E. Uhlmann, D. Oberschmidt, S. Frenzel, J. Polte
Investigation of heat flows during the milling processes through infrared thermography and inverse modelling
T. Helmig, T. Augspurger, Y. Frekers, B. Döbbeler, F. Klocke, R. Kneer
Thermally induced displacements of machine tool structure, tool and workpiece due to cutting processes
O. Horejš, M. Mareš, J. Hornych
A new calibration approach for a grey-box model for thermal
error compensation of a C-Axis
C. Brecher, R. Spierling, M. Fey
Investigation of passive torque of oil-air lubricated angular contact ball bearing and its modelling
J. Kekula, M. Sulitka, P. Kolář, P. Kohút, J. Shim, C. H. Park, J. Hwang
Cooling strategy for motorized spindle based on energy and power criterion to reduce thermal errors
S. Grama, A. N. Badhe, A. Mathur
Cooling potential of heat pipes and heat exchangers within a machine tool spindleo
B. Denkena, B. Bergman, H. Klemme, D. Dahlmann
Structure model based correction of machine tools
X. Thiem, B. Kauschinger, S. Ihlenfeldt
Optimal temperature probe location for the compensation of transient thermal errors
G. Aguirre, J. Cilla, J. Otaegi, H. Urreta
Adaptive learning control for thermal error compensation on 5-axis machine tools with sudden boundary condition changes
P. Blaser, J. Mayr, F. Pavliček, P. Hernández-Becerro, K. Wegener
Hybrid correction of thermal errors using temperature and deformation sensors
C. Naumann, C. Brecher, C. Baum, F. Tzanetos, S. Ihlenfeldt, M. Putz
Optimal sensor placement based on model order reduction
P. Benner, R. Herzog, N. Lang, I. Riedel, J. Saak
Workpiece temperature measurement and stabilization prior to dimensional measurement
N. S. Mian, S. Fletcher, A. P. Longstaff
Measurement of test pieces for thermal induced displacements on milling machines
H. Höfer, H. Wiemer
Model reduction for thermally induced deformation compensation of metrology frames
J. v. d. Boom
Local heat transfer measurement
A. Kuntze, S. Odenbach, W. Uffrecht
Thermal error compensation of 5-axis machine tools using a staggered modelling approach
J. Mayr, T. Tiberini. P. Blaser, K. Wegener
Design of a Photogrammetric Measurement System for Displacement and Deformation on Machine Tools
M. Riedel, J. Deutsch, J. Müller. S. Ihlenfeldt
Thermography on Machine Tools
M. Riedel, J. Deutsch, J. Müller, S. Ihlenfeldt
Test piece for thermal investigations of 5-axis machine tolls by on-machine measurement
M. Wiesener. P. Blaser, S. Böhl, J. Mayr, K. Wegener
48
Joy, Dawn, and Karthik Sekaran. "Electronic Pump Control and Benchmarking of Simulation Tools : AMESim and GT Suite." Thesis, Linköpings universitet, Fluida och mekatroniska system, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-69567.
Full textAbstract:
Load sensing pumps in hydraulic system of wheel loaders helps in increasing the energy efficiency of wheel loaders. Present day machines have hydro mechanical load sensing system. After the advent of hydro mechanical load sensing concept, over the years, lots of research has been carried out relevant to electro hydraulic load sensing, trying to control the pump electronically. Currently, Volvo Construction Equipments (VCE) is interested in investigating the possibility of implementing electro hydraulic load sensing system in the wheel loaders. Research works has shown existence of several configurations of electro hydraulic load sensing pumps. Successful simulation results of an electro hydraulic load sensing pump configuration would provide a backing for the proposal of building and testing that configuration of electro hydraulic load sensing pump prototype. Also, the thesis work aims in benchmarking hydraulic system simulation capabilities of AMESim and GT- Suite by simulating the existing hydro mechanical load sensing system in both in both the simulation packages.The thesis work has been carried out at Virtual Product Development (VPD) division of Volvo Construction Equipments (VCE), Eskilstuna, Sweden.
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Hall, Robert A. "Reliability analysis and discrete event simulation as tools for mining equipment management." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0035/NQ52824.pdf.
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Schmitt, Tobias [Verfasser]. "Degradation models and simulation tools for lithium and zinc batteries / Tobias Schmitt." Ulm : Universität Ulm, 2020. http://d-nb.info/1208766996/34.
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