To see the other types of publications on this topic, follow the link: Simulation.
Dissertations / Theses on the topic 'Simulation'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Simulation.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Frenzel, Erik. "Co-Simulation von LIGGGHTS® und SimulationX® zur Simulation des Zerkleinerungsprozesses in Brechern." Universitätsbibliothek Chemnitz, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-206919.
Full textAbstract:
In vielen Bereichen der Tagebautechnik spielt die Zerkleinerung von Material/ -strömen eine wesentliche Rolle, wobei sich je nach Material verschiedene Anforderungen an das Brechersystem ergeben. In Folge dessen werden Brecher auftragsspezifisch, meist für einen speziellen Gesteinstyp oder Einsatzort entwickelt oder modifiziert. Eine aussagekräftige Prognose der im Bruchprozess auftretenden Lasten auf den Brecher ist somit essentieller Bestandteil im Entwicklungsprozess.
Ein viel versprechender Ansatz, um das Materialverhalten in der Lastprognose zu berücksichtigen, ist die numerische Simulation des Materialbruchverhaltens mit Hilfe der Diskreten-Elemente-Methode (DEM). Das Verhalten der sogenannten Partikel wird über Kontakt- und bond-Modelle beschrieben und soll das makroskopische Verhalten des jeweiligen Gesteins möglichst realitätsnah abbilden.
Die Problematik ist, dass in SimulationX® keine Module zur DEM-Simulation vorhanden sind und umgekehrt in der DEM-Simulationsumgebung LIGGGHTSG® (LAMMPS improved for general granular and granular heat transfer simulations) keine derartige Maschinensimulation möglich ist. Der Ausweg ist die Co-Simulation zweier unterschiedlicher Simulationsumgebungen durch die Nutzung des ,,Functional Mock-Up Interface“-Standards (FMI).
Berechnungsergebnis sind die dynamischen Lasten auf den Brecher unter Berücksichtigung des Materialverhaltens. Somit können früher in der Brecherentwicklung Prognosen zu auftretenden Lasten getroffen und Einflussuntersuchungen von Maschinenkonfigurationen zur Effizienzsteigerungen durchgeführt werden, was zuvor auf Grund des Einzelanfertigungscharakters nicht möglich oder nicht wirtschaftlich war.
2
Dave, Jagrut Durdant. "Parallel Discrete Event Simulation Techniques for Scientific Simulations." Thesis, Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/6942.
Full textAbstract:
Exponential growth in computer technology, both in terms of individual CPUs and parallel technologies over the past decades has triggered rapid progress in large scale simulations. However, despite these achievements it has become clear that many conventional state-of-the-art techniques are ill-equipped to tackle problems that inherently involve multiple scales in configuration space. Our difficulty is that conventional ("time driven" or "time stepped") techniques update all parts of simulation space (fields, particles) synchronously, i.e. at time intervals assumed to be the same throughout the global computation domain or at best varying on a sub-domain basis (in adaptive mesh refinement algorithms).
Using a serial electrostatic model, it was recently shown that discrete event techniques can lead to more than two orders of magnitude speedup compared to the time-stepped approach. In this research, the focus is on the extension of this technique to parallel architectures, using parallel discrete event simulation. Previous research in parallel discrete event simulations of scientific phenomena has been limited
This thesis outlines a technique for converting a time-stepped simulation in the scientific domain into an equivalent parallel discrete event model. As a candidate simulation, an electromagnetic hybrid plasma simulation is considered. The experiments and analysis show the trade-offs on performance by varying the following factors: the simulations model characteristics (e.g. lookahead), applications load balancing, and accuracy of simulation results. The experiments are performed on a high performance cluster, using a conservative synchronization mechanism. Initial performance results are encouraging, demonstrating very good parallel speedup for large-scale model configurations containing tens of thousands of cells. Overheads for inter-processor communication remain a challenge for smaller computations.
3
Lee, David C. (David Chunyi) 1978. "Simulating Turbo codes using a modular simulation platform." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/87259.
Full text
4
Huang, Ya-Lin. "Ad hoc distributed simulation: a method for embedded online simulations." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/49060.
Full textAbstract:
The continual growth of computing power in small devices has motivated the development of novel approaches to optimizing operational systems efficiently and effectively. These optimization problems are often so complex that solving them analytically may be difficult, if not prohibited. One method for solving such problems is to use online simulation. However, challenges in using online simulation include the issues of responsiveness (e.g., because of communication delays), scalability, and failure resistance. To tackle these issues, this study proposes embedding online simulations into a network of sensors that monitors the system under investigation.
This thesis explores an approach termed “ad hoc distributed simulation,” which is based on embedding online simulations into a sensor network and adding communication and synchronization among simulators to model operational systems. This approach offers several potential advantages over existing approaches: (1) it can provide rapid response to system dynamics as well as efficiency since data exchange is local to the sensor network, (2) it can achieve better scalability to incorporate more sensors, and (3) it can provide better robustness to failures because portions of the system are still under local control. This research addresses several statistical issues in this ad hoc approach: (1) rapid and effective estimation of the input processes at model boundaries, (2) estimation of system-wide performance measures from individual simulator outputs, and (3) correction mechanisms responding to unexpected events or inaccuracies within the model.
This thesis examines ad hoc distributed simulation analytically and experimentally, mainly focusing on the accuracy of predicting the performance of open queueing networks. First, the analytical part formalizes the ad hoc approach and evaluates its accuracy at modeling certain class of open queueing networks with regard to the steady-state system performance measures. This work concerning steady-state metrics is extended to a broader class of networks by an empirical study, which presents evidence to show that the ad hoc approach can generate predictions comparable to those from sequential simulations. Furthermore, a “buffered-area” mechanism is proposed to substantially reduce prediction bias with a moderate increase in execution time.
In addition to those steady-state studies, another empirical study targets the prediction accuracy of the ad hoc approach at open queueing networks with short-term system-state transients. This study demonstrates that, with slight modification to the prior design of the ad hoc queueing simulation method for those steady-state studies, system dynamics can be well modeled. The results, again, support the conclusion that the ad hoc approach is competitive to the sequential simulation method in terms of prediction accuracy.
5
Wang, Xingang. "Multi-solver simulation with simulation backplane." Thesis, University of Southampton, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296386.
Full text
6
Bertelrud, P. Anders I. "An object-oriented simulator for the visual simulation environment." Thesis, This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-08142009-040521/.
Full text
7
Andersson, Håkan. "Parallel Simulation : Parallel computing for high performance LTE radio network simulations." Thesis, Mittuniversitetet, Institutionen för informationsteknologi och medier, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-12390.
Full textAbstract:
Radio access technologies for cellular mobile networks are continuously being evolved to meet the future demands for higher data rates, and lower end‐to‐end delays. In the research and development of LTE, radio network simulations play an essential role. The evolution of parallel processing hardware makes it desirable to exploit the potential gains of parallelizing LTE radio network simulations using multithreading techniques in contrast to distributing experiments over processors as independent simulation job processes. There is a hypothesis that parallel speedup gain diminishes when running many parallel simulation jobs concurrently on the same machine due to the increased memory requirements. A proposed multithreaded prototype of the Ericsson LTE simulator has been constructed, encapsulating scheduling, execution and synchronization of asynchronous physical layer computations. In order to provide implementation transparency, an algorithm has been proposed to sort and synchronize log events enabling a sequential logging model on top of non‐deterministic execution. In order to evaluate and compare multithreading techniques to parallel simulation job distribution, a large number of experiments have been carried out for four very diverse simulation scenarios. The evaluation of the results from these experiments involved analysis of average measured execution times and comparison with ideal estimates derived from Amdahl’s law in order to analyze overhead. It has been shown that the proposed multithreaded task‐oriented framework provides a convenient way to execute LTE physical layer models asynchronously on multi‐core processors, still providing deterministic results that are equivalent to the results of a sequential simulator. However, it has been indicated that distributing parallel independent jobs over processors is currently more efficient than multithreading techniques, even though the achieved speedup is far from ideal. This conclusion is based on the observation that the overhead caused by increased memory requirements, memory access and system bus congestion is currently smaller than the thread management and synchronization overhead of the proposed multithreaded Java prototype.
8
Singh, Harpreet. "Computer simulations of realistic microstructures implications for simulation-based materials design/." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/22564.
Full textAbstract:
Thesis (Ph. D.)--Materials Science and Engineering, Georgia Institute of Technology, 2008.<br>Committee Chair: Dr. Arun Gokhale; Committee Member: Dr. Hamid Garmestani; Committee Member: Dr. Karl Jacob; Committee Member: Dr. Meilin Liu; Committee Member: Dr. Steve Johnson.
9
Acél, Peter Paul Acél Peter Paul Acél Peter Paul Acél Peter Paul. "Methode zur Durchführung betrieblicher Simulationen : effiziente Optimierung der diskreten Simulation /." [S.l.] : [s.n.], 1996. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=11459.
Full text
10
Azhar, Mueed [Verfasser], and Jan G. [Akademischer Betreuer] Korvink. "Simulation of NMR experiments using particle simulation methods." Freiburg : Universität, 2018. http://d-nb.info/1155722485/34.
Full text
11
Gubba, Ravikumar Krishnanjan. "Distributed simulation of power systems using real time digital simulator." Master's thesis, Mississippi State : Mississippi State University, 2009. http://library.msstate.edu/etd/show.asp?etd=etd-06152009-222641.
Full text
12
Solis, Adrian (Adrian Orbita). "MIT Device Simulation WebLab : an online simulator for microelectronic devices." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/33364.
Full textAbstract:
Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, June 2005.<br>Includes bibliographical references (p. 149-157).<br>In the field of microelectronics, a device simulator is an important engineering tool with tremendous educational value. With a device simulator, a student can examine the characteristics of a microelectronic device described by a particular model. This makes it easier to develop an intuition for the general behavior of that device and examine the impact of particular device parameters on device characteristics. In this thesis, we designed and implemented the MIT Device Simulation WebLab ("WeblabSim"), an online simulator for exploring the behavior of microelectronic devices. WeblabSim makes a device simulator readily available to users on the web anywhere, and at any time. Through a Java applet interface, a user connected to the Internet specifies and submits a simulation to the system. A program performs the simulation on a computer that can be located anywhere else on the Internet. The results are then sent back to the user's applet for graphing and further analysis. The WeblabSim system uses a three-tier design based on the iLab Batched Experiment Architecture. It consists of a client applet that lets users configure simulations, a laboratory server that runs them, and a generic service broker that mediates between the two through SOAP-based web services. We have implemented a graphical client applet, based on the client used by the MIT Microelectronics WebLab.<br>(cont.) Our laboratory server has a distributed, modular design consisting of a data store, several worker servers that run simulations, and a master server that acts as a coordinator. On this system, we have successfully deployed WinSpice, a circuit simulator based on Berkeley Spice3F4. Our initial experiences with WeblabSim indicate that it is feature-complete, reliable and efficient. We are satisfied that it is ready for beta deployment in a classroom setting, which we hope to do in Fall 2004.<br>by Adrian Solis.<br>M.Eng.
13
Hassan, Aamir. "VANET Simulation." Thesis, Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-2687.
Full textAbstract:
<p>The number of automobiles has been increased on the road in the past few years. Due to high density of vehicles, the potential threats and road accident is increasing. Wireless technology is aiming to equip technology in vehicles to reduce these factors by sending messages to each other.</p><p>The vehicular safety application should be thoroughly tested before it is deployed in a real world to use. Simulator tool has been preferred over out door experiment because it simple, easy and cheap. VANET requires that a traffic and network simulator should be used together to perform this test. Many tools exist for this purpose but most of them have the problem with the proper interaction. In this thesis, we aim at simulating vehicular networks with external stimulus to analyze its effect on wireless communication but to do this job a good simulator is also needed. So we will first debate on the shortcoming of current simulators and come up with our own recommendations to perform our simulation.</p>
14
Wuerz, Daniela. "Mental Simulation." Diss., lmu, 2007. http://nbn-resolving.de/urn:nbn:de:bvb:19-82498.
Full text
15
Kesserwan, Nader. "Flight simulation." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0018/MQ55071.pdf.
Full text
16
Mochel, Thomas. "Objektorientierte Simulation : ein neues Konzept zur Simulation diskreter Systeme /." Aachen : Shaker, 1993. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=005334857&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
Full text
17
O'Keefe, R. M. "Developing simulation models : an interpreter for visual active simulation." Thesis, University of Southampton, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.236359.
Full text
18
Persson, Simon. "Simulation of processing equipment and evaluation of simulation software." Thesis, Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-79073.
Full textAbstract:
The cab assembly line in Oskarshamn is one of the world's most high tech production unit. With close to 300 robots the cab is assembled with merely programmed robots and no input from humans. Scania CV AB is a world leading manufacturer of trucks with high influence on the market globally. Even though robots do most of the work, there have been human brains behind the robot execution, and there is constant work ongoing to further increase efficiency and cycle times to meet the increasing global demand for logistics services. The robots are mainly programmed offline, using the ABB software Robotstudio, which basically creates a digital representation of the actual control system without interfering with the production. Testing upgraded programs as well as simulating them offline before implementation is an essential daily operation to make the production meet the demands. This thesis is divided into two objectives, one theoretical and one practical. The theoretical part focuses on the software, and consists of a critical analysis of a series of different software solutions for programming robots offline, as well as a look into how the offline programming processes work today in-house. The practical objective is to further improve the quality of the simulations conducted through creating tools to answer the calls from functional packages for the different processing equipment used on site. These functional packages lets you perform spot welding, gluing or gripping for instance, and as it is an outsourced service a lot of the coding is encrypted which prevents simulations being conducted with the pre-programmed routines, it makes the simulations crash. This report presents conclusions made regarding the use of offline programming equipment both in the regards of daily operations as well as long term strategies with digital twins and digitization. It also proves that the functional packages still can be simulated even though the code has been manipulated and encrypted at one point. It holds the complete ways of how to, from a 3D CAD model, create mechanisms, synchronize external axes, and creating smart components to answer digital inputs and presenting digital outputs to the system to have a fully functional simulation run.
19
Aryal, Babu Ram. "Developing the computer simulation model of buzz electronics simulation." Online version, 2009. http://www.uwstout.edu/lib/thesis/2009/2009aryalb.pdf.
Full text
20
Buchta, Christian, and Sara Dolnicar. "Learning by simulation. Computer simulations for strategic marketing decision support in tourism." SFB Adaptive Information Systems and Modelling in Economics and Management Science, WU Vienna University of Economics and Business, 2003. http://epub.wu.ac.at/1718/1/document.pdf.
Full textAbstract:
This paper describes the use of corporate decision and strategy simulations as a decision-support instrument under varying market conditions in the tourism industry. It goes on to illustrate this use of simulations with an experiment which investigates how successful different market segmentation approaches are in destination management. The experiment assumes a competitive environment and various cycle-length conditions with regard to budget and strategic planning. Computer simulations prove to be a useful management tool, allowing customized experiments which provide insight into the functioning of the market and therefore represent an interesting tool for managerial decision support. The main drawback is the initial setup of a customized computer simulation, which is time-consuming and involves defining parameters with great care in order to represent the actual market environment and to avoid excessive complexity in testing cause-effect-relationships. (author's abstract)<br>Series: Report Series SFB "Adaptive Information Systems and Modelling in Economics and Management Science"
21
Meleady, Rose. "Simulating social dilemmas : promoting cooperative behaviour through strategies of mental simulation." Thesis, University of Kent, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.633829.
Full textAbstract:
One of the most consistent findings in experimental social dilemmas research is the positive effect group discussion has on cooperative behaviour. At a time when cooperation is critical to tackle societal problems, ranging from debt to deforestation, understanding the dynamics of group discussion is a pressing need. Unfortunately, research investigating the processes underlying the effect has stalled in a state of disagreement, whilst applications have been discouraged by the realisation that discussion amongst all decision-makers is often difficult to establish. The first part of this thesis uniquely integrates previously competing 'single-cause' explanations of the group discussion effect into a single process model of group discussion, providing a more complete theoretical picture of how intenelated factors combine to facilitate discussion induced cooperation. On the basis of this theoretical analysis, complimentary approaches to the indirect and feasible implementation of group discussion are proposed, including the entirely new concept of imagined group discussion. Results within the second part of the thesis support the conclusion that when individuals imagine discussing a social dilemma with nominal group members they engage in cognitive processes consonant with those underlying the direct group discussion effect, thereby resulting in higher levels of cooperative behaviour. The third part of the thesis demonstrates that when the size of the group facing the dilemma is so large that even imagining a discussion amongst all decision-makers becomes impracticable (i.e. within global-level dilemmas), an imagined discussion with a single outgroup member successfully encourages collectively beneficial decision-making. The use of imagined communication techniques is therefore advocated as a simple, versatile and inexpensive means of encouraging cooperative behaviour without the limiting requirement of proximity between discussants.
22
Bylander, Ulf. "Flight Path Simulation Application : A flight simulator for charged particle transport." Thesis, Uppsala universitet, Högenergifysik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-227759.
Full textAbstract:
CTF3 is a test facility for a new CLIC high energy linear collider. For this beamsteering and beam focusing is vital. Because physically running a beamline and changingsetup is expensive and takes much effort it is beneficial to use a simulator for thebeamline. The transportation of the beam through the beamline can be representedwith matrix multiplications and for this reason MATLAB is a fitting environment tosimulate in. A Flight Path Simulator was written in MATLAB and was succefullyimplemented and tested for the CALIFES beamline of the two-beam test stand that ispart of the CTF3 facility.
23
Schmitz, Anja. "Basic anesthesia skills simulation curriculum for medical students development and empirical evaluation based on an instructional design model /." [S.l. : s.n.], 2006. http://nbn-resolving.de/urn:nbn:de:bsz:16-opus-71870.
Full text
24
Lamers, Eugen. "Contributions to Simulation Speed-up : Rare Event Simulation and Short-term Dynamic Simulation for Mobile Network Planning /." Wiesbaden : Vieweg + Teubner in GWV Fachverlage, 2008. http://d-nb.info/988382016/04.
Full text
25
Lamers, Eugen. "Contributions to simulation speed-up rare event simulation and short-term dynamic simulation for mobile network planning." Wiesbaden Vieweg + Teubner, 2007. http://d-nb.info/988382016/04.
Full text
26
Hultberg, Ida. "Modelling and Simulation of Unknown Factors in Simulation Based Acquisition." Thesis, University of Skövde, Department of Computer Science, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-715.
Full textAbstract:
<p>When a new product should be acquired, a model over its functionality is made. A quite new idea in the military area is to use simulations to find out what and how much to acquire. Since the product never has been on the market before it is hard to know how factors in the surroundings, like weather and other active objects, will affect it. Therefore these unknown factors that appear during the creation or acquiring of a new product need to be taken into consideration.</p><p>A literature study is performed about how modelling of simulations can be done, and how unknown factors can be considered when modelling a simulation. The study goes into if unknown factors are taken into consideration when modelling in the Process component in Simulation Based Acquisition (SBA). The result of this study shows that SBA facilitates in the process of finding and reducing unknown factors.</p>
27
Aronsson, Peter. "Automatic Parallelization of Simulation Code from Equation Based Simulation Languages." Licentiate thesis, Linköping University, Linköping University, PELAB - Programming Environment Laboratory, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-5720.
Full textAbstract:
<p>Modern state-of-the-art equation based object oriented modeling languages such as Modelica have enabled easy modeling of large and complex physical systems. When such complex models are to be simulated, simulation tools typically perform a number of optimizations on the underlying set of equations in the modeled system, with the goal of gaining better simulation performance by decreasing the equation system size and complexity. The tools then typically generate efficient code to obtain fast execution of the simulations. However, with increasing complexity of modeled systems the number of equations and variables are increasing. Therefore, to be able to simulate these large complex systems in an efficient way parallel computing can be exploited.</p><p>This thesis presents the work of building an automatic parallelization tool that produces an efficient parallel version of the simulation code by building a data dependency graph (task graph) from the simulation code and applying efficient scheduling and clustering algorithms on the task graph. Various scheduling and clustering algorithms, adapted for the requirements from this type of simulation code, have been implemented and evaluated. The scheduling and clustering algorithms presented and evaluated can also be used for functional dataflow languages in general, since the algorithms work on a task graph with dataflow edges between nodes.</p><p>Results are given in form of speedup measurements and task graph statistics produced by the tool. The conclusion drawn is that some of the algorithms investigated and adapted in this work give reasonable measured speedup results for some specific Modelica models, e.g. a model of a thermofluid pipe gave a speedup of about 2.5 on 8 processors in a PC-cluster. However, future work lies in finding a good algorithm that works well in general.</p><br>Report code: LiU-Tek-Lic-2002:06.
28
Meliorisz, Péter Bálint [Verfasser]. "Simulation of Proximity Printing : Simulation der Nahfeldbelichtung / Péter Bálint Meliorisz." Aachen : Shaker, 2011. http://d-nb.info/1098039688/34.
Full text
29
Cherif, Redha. "Software Process Simulation Modelling : A Multi Agent-Based Simulation Approach." Thesis, Blekinge Tekniska Högskola, Avdelningen för programvarusystem, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-5787.
Full textAbstract:
In this research we present one of the first actual applications of Multi Agent-Based Simulation (MABS) to the field of software process simulation modelling (SPSM). Although a few previous applications were attempted, we explain in our literature review how these failed to take full advantage of the agency paradigm. Our research resulted in a model of the software development process that integrates performance, cognition and artefact quality, for which we built a common simulation framework to implement and run MABS and System Dynamics (SD) simulators upon the same integrated models. Although it is not possible to fully verify and validate implementations and models like ours, we used a number of verification and validation techniques to increase our confidence in these. Our work is also quite unique in that it compares MABS to SD in the context of SPSM. Here, we uncovered quite interesting properties of each simulation approach and how MABS, for example, is "risk averse" when compared to SD. In our discussion section we also present a number of lessons learned regarding the two simulation paradigms as well as various shortcomings in the models we adopted and our own.
30
Guo, Song. "Simulation Software as a Service and Service-Oriented Simulation Experiment." Digital Archive @ GSU, 2012. http://digitalarchive.gsu.edu/cs_diss/69.
Full textAbstract:
Simulation software is being increasingly used in various domains for system analysis and/or behavior prediction. Traditionally, researchers and field experts need to have access to the computers that host the simulation software to do simulation experiments. With recent advances in cloud computing and Software as a Service (SaaS), a new paradigm is emerging where simulation software is used as services that are composed with others and dynamically influence each other for service-oriented simulation experiment on the Internet.
The new service-oriented paradigm brings new research challenges in composing multiple simulation services in a meaningful and correct way for simulation experiments. To systematically support simulation software as a service (SimSaaS) and service-oriented simulation experiment, we propose a layered framework that includes five layers: an infrastructure layer, a simulation execution engine layer, a simulation service layer, a simulation experiment layer and finally a graphical user interface layer. Within this layered framework, we provide a specification for both simulation experiment and the involved individual simulation services. Such a formal specification is useful in order to support systematic compositions of simulation services as well as automatic deployment of composed services for carrying out simulation experiments. Built on this specification, we identify the issue of mismatch of time granularity and event granularity in composing simulation services at the pragmatic level, and develop four types of granularity handling agents to be associated with the couplings between services. The ultimate goal is to achieve standard and automated approaches for simulation service composition in the emerging service-oriented computing environment. Finally, to achieve more efficient service-oriented simulation, we develop a profile-based partitioning method that exploits a system’s dynamic behavior and uses it as a profile to guide the spatial partitioning for more efficient parallel simulation. We develop the work in this dissertation within the application context of wildfire spread simulation, and demonstrate the effectiveness of our work based on this application.
31
Tomlinson, S. P. "The hydraulic automatic simulation package (HASP) : Modelling and simulation aspects." Thesis, University of Bath, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375337.
Full text
32
Pingaud, Hervé. "Simulation statique et simulation dynamique des échangeurs à plaques brasées." Toulouse, INPT, 1988. http://www.theses.fr/1988INPT028G.
Full textAbstract:
Programme integrant toutes les configurations de cette categorie d'echangeurs, a partir d'une description precise de sa geometrie. Determination des limites de son fonctionnement, particulierement des deviations des flux thermiques entre les passages. Description du modele. Illustration des performances du programme par quelques exemples en regimes permanent et transitoire
33
Bramler, Arild. "Towards improved simulation process capabilities : A simulation process maturity model." Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-44355.
Full textAbstract:
Purpose – The purpose of this thesis is to present the result of simulation process maturity (SPM) assessments in the pharmaceutical and manufacturing industry using a process maturity model derived from empirical research. The model is used to benchmark an organisations simulation capability and to apply the results of the assessment to develop a road map for implementing simulation process improvement as well as integration initiatives within the organisation. Methodology approach – This is a survey-based research on benchmarking simulation process in the industry. The SPM model was adopted as the reference model and data were collected through interviews with key simulation staff within each organisation with the aim of identifying anomalies or conformities in the way simulation projects are performed. A pragmatic scoring system was introduced based on the fulfilment of defined requirements to score findings from the interviews based on defined SPM tenets and the sample profiles SPM tier calculated. Findings – Each tenet of the SPM model consists of 3 maturity tiers with increasing level of complexity of the process. The results of the assessment showed that the overall average of SPM of the sample profile is at tier 2. Key discrepancies representing the lowest and highest ratings are found to be mostly related to process understanding and management commitment. A higher mean score is recognised for the samples displaying a deeper integration with top management and alignment with organisational strategic objectives. These maturity tiers and tenets reflect the extent of the implementation of contracting best practices within the studied industries. Research limitations/implications – This thesis uses a purposeful sampling approach designed at acquiring data on an organisational current simulation process. The assessment survey was conducted solely on qualified simulation personal within pharmaceutical and manufacturing. It is as such not clear whether the proposed SPM model will work within other types of industrial settings and if so how to organise the simulation activities in that setting. By purposively selecting the sample profile there are limitations concerning generalizability. Still, the conclusion based on the analysis of these benchmarking assessments may offer key take-aways in the context of process management. Practical implications – The findings suggest that benchmarking can be effective in measuring and improving simulation process capabilities within the pharmaceutical and manufacturing industry. The use of these benchmarking assessment can be instrumental in tracking the achievements of this process and enable management to measure the quality of the simulation activities in addition to offer guidance on what development actions to prioritise. By improving the simulation process, organisations will work towards furthering the integrity and credibility of its simulation studies. Originality/value – The existing literature does properly not present adequate empirical research in the field on maturity on the simulation process. Also, the analysis method used in this study will further help organisation to perform self-assessment and determine their respective SPM. This value is reflected in using the results for implementing simulation process improvement initiatives that will ensure that the process is conducted in the most effective and efficient way.
34
Tang, Wei. "Reconfigurable Hardware-Based Simulation Modeling of Flexible Manufacturing Systems." Diss., Virginia Tech, 2005. http://hdl.handle.net/10919/29925.
Full textAbstract:
This dissertation research explores a reconfigurable hardware-based parallel simulation mechanism that can dramatically improve the speed of simulating the operations of flexible manufacturing systems (FMS). Here reconfigurable hardware-based simulation refers to running simulation on a reconfigurable hardware platform, realized by Field Programmable Gate Array (FPGA). The hardware model, also called simulator, is specifically designed for mimicking a small desktop FMS. It is composed of several micro-emulators, which are capable of mimicking operations of equipment in FMS, such as machine centers, transporters, and load/unload stations.
To design possible architectures for the simulator, a mapping technology is applied using the physical layout information of an FMS. Under such a mapping method, the simulation model is decomposed into a cluster of micro emulators on the board where each machine center is represented by one micro emulator. To exploit the advantage of massive parallelism, a kind of star network architecture is proposed, with the robot sitting at the center. As a pilot effort, a prototype simulator has been successfully built.
A new simulation modeling technology named synchronous real-time simulation (SRS) is proposed. Instead of running conventional programs on a microprocessor, this new technology adopts several concepts from electronic area, such as using electronic signals to mimic the behavior of entities and using specifically designed circuits to mimic system resources. Besides, a time-scaling simulation method is employed. The method uses an on-board global clock to synchronize all activities performed on different emulators, and by this way tremendous overhead on synchronization can be avoided. Experiments on the prototype simulator demonstrate the validity of the new modeling technology, and also show that tremendous speedup compared to conventional software-based simulation methods can be achieved.<br>Ph. D.
35
Richart, Nicolas. "Conception et mise en oeuvre d'une plate-forme de pilotage de simltions numériques parallèles et distribuées." Thesis, Bordeaux 1, 2010. http://www.theses.fr/2010BOR13991/document.
Full textAbstract:
Le domaine de la simulation numérique évolue vers des simulations de phénomènes physiques toujours plus complexes. Cela se traduit typiquement par le couplage de plusieurs codes de simulation, où chaque code va gérer une physique (simulations multi-physiques) ou une échelle particulière (simulations multi-échelles). Dans ce cadre, l'analyse des résultats des simulations est un point clé, que ce soit en phase de développement pour valider les codes ou détecter des erreurs, ou en phase de production pour confronter les résultats à la réalité expérimentale. Dans tous les cas, le pilotage de simulations peut aider durant ce processus d'analyse des résultats. L'objectif de cette thèse est de concevoir et de réaliser une plate-forme logicielle permettant de piloter de telles simulations. Plus précisément, il s'agit à partir d'un client de pilotage distant d'accéder ou de modifier les données de la simulation de manière cohérente, afin par exemple de visualiser "en-ligne" les résultats intermédiaires. Pour ce faire, nous avons proposé un modèle de pilotage permettant de représenter des simulations couplées et d'interagir avec elles efficacement et de manière cohérente. Ces travaux ont été validés sur une simulation multi-échelles en physique des matériaux<br>The numerical simulations evolve more and more to simulations of complex physical phenomena through multi-scale or multi-physics codes. For these kind of simulations data analysis is a main issue for many reasons, as detecting bugs during the development phase or to understand the dynamic of the physical phenomena simulated during the production phase. The computational steering is a technique well suited to do all this kind of data analysis. The goal of this thesis is to design and develop a computational steering framework that take into account the complexity of coupled simulations. So, through a computational steering client we want to interact coherently with data generated in coupled simulations. This afford for example to visualize on-line the intermediate results of simulations. In order to make this possible we will introduce an abstract model that enables to represent coupled simulations and to know when we can interact coherently with them. These works have been validated on a legacy multi-scale simulation of material physics
36
Celik, Nurcin. "INTEGRATED DECISION MAKING FOR PLANNING AND CONTROL OF DISTRIBUTED MANUFACTURING ENTERPRISES USING DYNAMIC-DATA-DRIVEN ADAPTIVE MULTI-SCALE SIMULATIONS (DDDAMS)." Diss., The University of Arizona, 2010. http://hdl.handle.net/10150/195427.
Full textAbstract:
Discrete-event simulation has become one of the most widely used analysis tools for large-scale, complex and dynamic systems such as supply chains as it can take randomness into account and address very detailed models. However, there are major challenges that are faced in simulating such systems, especially when they are used to support short-term decisions (e.g., operational decisions or maintenance and scheduling decisions considered in this research). First, a detailed simulation requires significant amounts of computation time. Second, given the enormous amount of dynamically-changing data that exists in the system, information needs to be updated wisely in the model in order to prevent unnecessary usage of computing and networking resources. Third, there is a lack of methods allowing dynamic data updates during the simulation execution. Overall, in a simulation-based planning and control framework, timely monitoring, analysis, and control is important not to disrupt a dynamically changing system. To meet this temporal requirement and address the above mentioned challenges, a Dynamic-Data-Driven Adaptive Multi-Scale Simulation (DDDAMS) paradigm is proposed to adaptively adjust the fidelity of a simulation model against available computational resources by incorporating dynamic data into the executing model, which then steers the measurement process for selective data update. To the best of our knowledge, the proposed DDDAMS methodology is one of the first efforts to present a coherent integrated decision making framework for timely planning and control of distributed manufacturing enterprises.To this end, comprehensive system architecture and methodologies are first proposed, where the components include 1) real time DDDAM-Simulation, 2) grid computing modules, 3) Web Service communication server, 4) database, 5) various sensors, and 6) real system. Four algorithms are then developed and embedded into a real-time simulator for enabling its DDDAMS capabilities such as abnormality detection, fidelity selection, fidelity assignment, and prediction and task generation. As part of the developed algorithms, improvements are made to the resampling techniques for sequential Bayesian inferencing, and their performance is benchmarked in terms of their resampling qualities and computational efficiencies. Grid computing and Web Services are used for computational resources management and inter-operable communications among distributed software components, respectively. A prototype of proposed DDDAM-Simulation was successfully implemented for preventive maintenance scheduling and part routing scheduling in a semiconductor manufacturing supply chain, where the results look quite promising.
37
Scaparrotti, Giacomo. "Cross-simulator integration: ns3 as a network simulation back-end for Alchemist." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/20440/.
Full textAbstract:
Innovative distributed systems are often studied with the aid of simulation, especially in the case of large scale and situated systems. One of the key aspects of distributed systems is the presence of a set of nodes which must communicate with each other in order to perform their collective task. Consequently, the behaviour of the network plays a key role in determining how the distributed system will act as a whole, but support for realistic simulation of network communication may not be available in simulators that focus on higher-level phenomena, such as the execution of a program on the nodes belonging to a distributed system. Network simulation is usually performed with dedicated simulators which, on the other hand, mostly focus on low-level aspects, such as the behaviour of the physical channels and of the network protocols. The present works aims at filling this gap between high-level distributed system simulation and low-level network simulation by creating a cross-simulator integration between Alchemist, a simulator for large scale situated distributed systems, and ns3, a network simulator, which has been exploited in order to give Alchemist the ability to accurately simulate the network interactions between the nodes. Finally, the whole system has been tested to demonstrate how different network setups can affect the execution of a program in a distributed system.
38
Demange, Jonathan. "Un modèle d'environnement pour la simulation multiniveau - Application à la simulation de foules." Phd thesis, Université de Technologie de Belfort-Montbeliard, 2012. http://tel.archives-ouvertes.fr/tel-00863674.
Full textAbstract:
Cette thèse propose un modèle organisationnel et holonique de l'environnement pour la simulation des déplacements de piétons dans des bâtiments. Une foule de piétons peut être considérée comme un système composé d'un grand nombre d'entités en interaction, dont la dynamique globale ne peut se réduire à la somme des comportements de ses composants. La simulation multiniveau fondée sur les modèles multiagents holoniques constitue une approche permettant d'analyser la dynamique de tels systèmes. Elle autorise leur analyse en considérant plusieurs niveaux d'observation (microscopique, mésoscopique et macroscopique) et prend en compte les ressources de calcul disponibles. Dans ces systèmes, l'environnement est considéré comme l'une des parties essentielles. La dynamique des piétons composant la foule est alors clairement distinguée de celle de l'environnement dans lequel ils se déplacent. Un modèle organisationnel décrivant la structure et la dynamique de l'environnement est proposé. L'environnement est structurellement décomposé en zones, sous-zones, etc. Les organisations et les rôles de cet environnement sont projetés dans une société d'agents ayant en charge de simuler la dynamique de l'environnement et les différentes missions qui lui sont classiquement assignées dans les systèmes multiagents. Ce modèle précise également les règles de passage entre deux niveaux d'observation. Ainsi, chaque agent appartenant au modèle de l'environnement tente d'utiliser une approximation des comportements de ses sous-zones afin de limiter la consommation de ressources durant la simulation. La qualité de l'approximation entre ces deux niveaux d'observation est évaluée avec des indicateurs énergétiques. Ils permettent de déterminer si l'agent approxime correctement les comportements des agents associés aux sous-zones. En sus du modèle organisationnel et holonique proposé, nous présentons un modèle concret de la simulation de voyageurs dans un terminal d'aéroport. Ce modèle concret est implanté sur les plateformes JaSIM et Janus.
39
Poeffel, Alexander. "Simulation hochbelasteter Kreisel /." Zürich : Wirtschaftswissenschaftliche Fakultät der Universität Zürich, 2006. http://opac.nebis.ch:80/F/?func=service&doc_library=EBI01&doc_number=005275438&line_number=0001&func_code=WEB-FULL&service_type=MEDIA.
Full text
40
Steingass, Alexander. "Simulation von Navigationssystemen." [S.l.] : [s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=964538040.
Full text
41
Jones, Doreen M. "Robot wars simulation." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1997. http://handle.dtic.mil/100.2/ADA333463.
Full text
42
Kramper, Wolfgang. "Simulation von Schwarmverhalten." Berlin mbv, Mensch-und-Buch-Verl, 2010. http://d-nb.info/1002925584/04.
Full text
43
Mårtensson, Frans, and Per Jönsson. "Software Architecture Simulation." Thesis, Blekinge Tekniska Högskola, Institutionen för programvaruteknik och datavetenskap, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-4087.
Full textAbstract:
A software architecture is one of the first steps towards a software system. A software architecture can be designed in different ways. During the design phase, it is important to select the most suitable design of the architecture, in order to create a good foundation for the system. The selection process is performed by evaluating architecture alternatives against each other. We investigate the use of continuous simulation of a software architecture as a support tool for architecture evaluation. For this purpose, we study a software architecture of an existing software system in an experiment, where we create a model of it using a tool for continuous simulation, and simulate the model. Based on the results from the simulation, we conclude that the system is too complex to be modeled for continuous simulation. Problems we identify are that we need discrete functionality to be able to correctly simulate the system, and that it is very time-consuming to develop a model for evaluation purposes. Thus, we find that continuous simulation is not appropriate for evaluating a software architecture, but that the modeling process is a valuable tool for increasing knowledge and understanding about an architecture.
44
Du, Jianyi. "Combustion CFD simulation." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0018/NQ56437.pdf.
Full text
45
Abdel-Khalik, Hany Samy. "Adaptive Core Simulation." NCSU, 2004. http://www.lib.ncsu.edu/theses/available/etd-10252004-094938/.
Full textAbstract:
The work presented in this thesis is a continuation of a master?s thesis research project conducted by the author to gain insight into the applicability of inverse methods to developing adaptive simulation capabilities for core physics problems. Use of adaptive simulation is intended to improve the fidelity and robustness of important core attributes predictions such as core power distribution, thermal margins and core reactivity. Adaptive simulation utilizes a selected set of past and current reactor measurements of reactor observables to adapt the simulation in a meaningful way that is reflected in higher fidelity and robustness of the adapted core simulators models. We propose an inverse theory approach in which the multitudes of input data to core simulators, i.e. reactor physics and thermal-hydraulic data, are to be adjusted to improve agreement with measured observables while keeping core simulators models unadapted. At a first glance, devising such adaption for typical core simulators models would render the approach impractical. This follows, since core simulators are based on very demanding computational models, i.e. based on complex physics models with millions of input data and output observables. This would spawn not only several prohibitive challenges but also numerous disparaging concerns. The challenges include the computational burdens of the sensitivity-type calculations required to construct Jacobian operators for the core simulators models. Also, the computational burdens of the uncertainty-type calculations required to estimate the uncertainty information of core simulators input data presents a demanding challenge. The concerns however are mainly related to the reliability of the adjusted input data. We demonstrate that the power of our proposed approach is mainly driven by taking advantage of this unfavorable situation and show that significant reductions in both computational and storage burdens can be attained for a typical BWR core simulator adaption problem without compromising the quality of the adaption.
46
Hecht, Martin. "Simulation of peloids." kostenfrei, 2007. http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-29653.
Full text
47
Pope, Michael T. "VLSI systems simulation /." Title page, table of contents and abstract only, 1991. http://web4.library.adelaide.edu.au/theses/09PH/09php826.pdf.
Full text
48
Bradley, Colin Bueth. "Microclustered optimistic simulation." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=19273.
Full textAbstract:
Software-driven simulation as a design and verification tool has become almost ubiquitous in today's industrial and technology-based society. As systems grow in scale and complexity, often on a non-linear basis, demands on simulation change accordingly. Distributed simulation is one approach to deal with such growth. As distributed simulation becomes the norm in various contexts, focus has shifted to the efficiencies of such simulations. A popular approach has been to partition a given problem into sub-units in such a manner as to increase the efficiency of the simulation run. Further, efforts have been made to dynamically re-partition the problem units using run-time metrics. Noting the limitations of static partitioning and contrasting dynamic re-partitioning, this thesis approaches simulation efficiency by proposing an initial over-partitioning of the problem. Using run-time data, we hope to discover potential efficiencies and exploit them by dynamically amalgamating these ''micro-clusters'' as suggested by run-time analysis.<br>La simulation menée par logiciel comme outil de conception et de vérification est devenue presque omniprésente dans la société industrielle et basée sur la technologe d'aujourd'hui. Comme les systèmes se développent en éechelle et en complexité, souvent sur une base non linéaire, les exigences sur la simulation changent en conséquence. La simulation distribuée est une approche pour traiter d'une telle croissance. Alors que la simulation distribuée devient la norme dans divers contextes, le centre d'intérêt s'est porté sur l'efficacité de telles simulations. Une approche populaire a été de diviser un problème donné dans des sous-unités de manière à optimiser l'efficacité de la simulation. De plus, des efforts ont été faits pour répartir les unités de problème en utilisant des données d'exécution. Prenant en compte les limitations de la division statique des partitions et contraste dynamique, cette thèse approche l'efficacité de simulation en proposant une répartition de niveau supérieur du problème. En utilisant des données d'exécution, nous espérons découvrir des efficacités potentielles et les exploiter en amalgamant dynamiquement ces ''microamas'' comme suggérés par l'analyse d'exécution.
49
Oses, Noelia. "Component-based simulation." Thesis, Lancaster University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.414597.
Full text
50
Yu, Xiaoning. "Distributed interactive simulation." Thesis, Brunel University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310078.
Full text