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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

A SIMULATION-BASED FRAMEWORK FOR AS-BUILT DOCUMENTATION OF CONSTRUCTION PROCESS AND PRODUCT INFORMATION

Moghani, Elmira Unknown Date
No description available.
32

Simulation Of Yacht Movements In Gocek Bays

Numanoglu Genc, Asli 01 March 2004 (has links) (PDF)
Fethiye-G&ouml / cek area is one of the nine coastal Specially Protected Area (SPA) in Turkey. Since mid-80&rsquo / s G&ouml / cek town has developed to be a yachting center, and the bays of G&ouml / cek have acquired a well-earned international fame as a paradise for boating vacations. However, the uncontrolled yachting in this bay area presents a growing pressure on the environment, and the coastal and marine ecosystem. In this thesis a computer model for simulating the movements of yachts in G&ouml / cek Bays is developed. The computer model uses the Multinomial Logit Model (MNL) to find the probabilities for the boaters to select the next bay to visit. The model predicts the number of boats in each bay at the end of a day, the number of boats visited each bay during the day and the distribution of boater categories among the bays throughout the simulation time. In order to get the data needed for the inputs, a questionnaire was formed, and a detailed survey was carried out in G&ouml / cek Bays. In addition to the questionnaires, the number of the boats anchored were also observed in the field studies. The model is applied to the G&ouml / cek Bays and the results obtained are compared with the data obtained in the field. In the following years, the yacht movements and distributions at various anchor locations can be predicted with this model. These predictions will be useful in a future management plan that aims to control of yacht movement and anchoring.
33

Simulation Modeling Of Shop Floor Activities For Smes In Virtual Enterprises

Bahtiyar, Mustafa 01 June 2005 (has links) (PDF)
The globalization of the markets and the worldwide competition forces the SMEs to implement new technologies and organize themselves using new concepts in order to maintain their competitivity. This type of temporary alliance is called as Virtual Enterprise (VE). SMEs seem to be appropriate units for building this type of temporary alliances when their properties (such as flexibility, adaptability and agility) are taken into account. This study is concerned with the simulation modeling of shop floor activities for SMEs in VEs. Analyzing the SMEs with their current and new work load over the existing one by using simulation tool may help the VE management unit to see the most appropriate SMEs for the projects. Because of mentioned advantages, this thesis will test whether the simulation tool will or will not be used in the selection of the VE partner. The simulation methodology for modeling shop floor activities of SMEs was developed by using ARENA simulation tool in this thesis. A hydraulic cylinder company was selected for pilot application. Manufacturing of twelve basic hydraulic cylinders was studied in the developed model. Four different queue rules were applied to the developed model to optimize the system efficiency. By analyzing the output statistical results of ARENA which were obtained with the usage of the input variables of SME (such as resource capacities, process times, setup and remove times of parts, variables wrt to workers, etc.) best manufacturing policy for pilot SME was able to be found. To see the response of the system under different circumstances, grinding and hardening operations for a drive shaft manufacturing were assigned to the company. This new job was applied on two models (Base Model and Optimized System Model) and the statistical results of each were examined.
34

Simulation Of A Flexible Manufacturing System: A Pilot Implementation

Yucel, Necati Deniz 01 September 2005 (has links) (PDF)
Manufacturing industry has made extensive use of simulation as a means of trying to model the impact of variability on manufacturing system behavior and to explore various ways of coping with change and uncertainty. Simulation helps find optimal solutions to a number of problems at both design and application stages of Flexible Manufacturing Systems (FMS&rsquo / s) serving to improve the &ldquo / flexibility&rdquo / level The flexibility requirement of FMS necessitates the dissemination of every activity that concerns production, throughout all the levels of a company forcing almost every level of employee face with simulation software, either in terms of preparing models, modifying runs or evaluating results. This problem of inadequate capability of personnel to utilize simulation effectively can be overcome through the design of custom interfaces and integration of simulation software with everyday-use programs. This research mainly focuses on realizing the modeling and simulation of FMS&rsquo / s by the use of the existing system in Middle East Technical University, Mechanical Engineering Department, Computer Integrated Manufacturing Laboratory as a test-bed. Additionally, the means of integration of simulation with auxiliary programs is demonstrated. The models developed throughout the study using ARENA&reg / are used to come up with different scenarios of production. Sample results and decisions about production issues that can be attained through the use of simulation are provided. The described model creation procedures, the generated models, and result assessments are expected to act as a guideline for other simulations regarding FMS&rsquo / s.
35

Software Architecture Simulation

Mårtensson, Frans, Jönsson, Per January 2002 (has links)
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.
36

Simulační modelování bezpilotního letounu / Fixed-wing UAV simulation modeling

Příleský, Libor January 2014 (has links)
Nowadays number of UAVs is still increasing. If we want to design their autopilot system, we need a simulation model to test and tune our autopilot design. This thesis is about creating such model fo small fixed wing UAV. This thesis contain information how to create the model, which equations to use and what various parameters mean. One of the possibilities is parameter identification from measured data. In later part of this paper is a small research of this topic and implementation of two of them. Virtual model, which is obtained at the end of this work, accomplished its primary goal and was used to initial autopilot design. Implemented identification methods worked as well, but we didn't succeed in upgrading the model parameters due to the defects during the data measurement.
37

Integrated automotive manufacturing supply

Van Dyk, Petrus Jakobus Schoeman 10 June 2005 (has links)
Supply planning and traffic flow planning are major activities in the automotive manufacturing environment worldwide. Supply planning directly influences the traffic within a manufacturing plant. The impact of supply planning strategies like Just-in-Time, Just-in-Sequence and Direct Supply on plant traffic is rarely considered, as supply and traffic flow planning are traditionally seen as separate activities. BMW SA and other automotive manufacturers are facing various specific problems relating to supply and traffic flow planning. One of these problems is in selecting the best supplier transportation medium among various alternatives for the supply of each part family, taking into account the effects on plant traffic. Several variables have to be considered during this decision making process, and no concrete decision support tool exists at present to assist during this process. Another specific problem faced by automotive manufacturers today lies in accessing the impact of physical relocation decisions on plant traffic. Several proposed plant layout changes and changes to the location of supplier delivery points exist for BMW Plant 9 in Rosslyn. These proposed changes will imply large relocation expenses, and will inevitably have a major impact on the traffic flow within the plant. The respective impact of these proposed layout changes have to be investigated, analysed and compared. Tools developed during this project will assist automotive manufacturers during the supply planning phase of their logistics planning process. Even though these tools can function independently, their real value is only realised once they are used in conjunction with each other as a Decision Support System (DSS) (see chapter 6: Decision Support Systems). In essence, this DSS consists of a Supply Medium Decision Support Tool (SMDST) and a traffic flow simulation model. The effects of certain decisions considered during the supply planning process (as described inChapter 2: Problem Statement) and the impact of these decisions on plant traffic can now be systematically evaluated (see Figure A): -- Firstly: by means of the SMDST, which provides critical information about the cost implication and number of deliveries required for all possible combinations of part families and delivery vehicles used -- Secondly: the simulation model’s input data file can easily be updated in accordance to the SMDST’s information in preparation of a new simulation experiment -- Thirdly: the traffic flow simulation model can be run. The model will automatically use the updated input data file and create unique results files for the scenario currently under analysis -- Fourthly: the simulation model’s results files can be viewed and compared to those of previous scenarios (See figure A in 00front) All the user requirements as stated in the user requirements specifications (sections 8.2 and 9.2) have been met. Every component of the DSS was developed generically as far as possible, allowing the user to adapt it to other similar manufacturing plants with relative ease. By utilising this DSS, scenarios can be evaluated and compared faster, more efficiently and by means of more quantitative measures than before, considerably reducing uncertainty and risk of planning. Certainly, this system supports automotive manufacturers in their quest towards manufacturing excellence in an ever-increasing internationally competitive and complex environment. / Dissertation (MEng (Industrial Engineering))--University of Pretoria, 2004. / Industrial and Systems Engineering / unrestricted
38

A Modeling Approach for Evaluating Network Impacts of Operational-Level Transportation Projects

Diekmann, Joshua James 26 May 2000 (has links)
This thesis presents the use of microscopic traffic simulation models to evaluate the effects of operational-level transportation projects such as ITS. A detailed framework outlining the construction and calibration of microscopic simulation models is provided, as well as the considerations that must be made when analyzing the outputs from these models. Two case studies are used to reinforce the concepts presented. In addition, these case studies give valuable insight for using the outlined approach under real-world conditions. The study indicates a promising future for the use of microsimulation models for the purpose of evaluating operational-level projects, as the theoretical framework of the models is sound, and the computational strategies used are feasible. There are, however, instances where simulation models do not presently model certain phenomena, or where simulation models are too computationally intensive. Comprehensive models that integrate microscopic simulation with land use planning and realistic predictions of human behavior, for instance, cannot practically be modeled in contemporary simulation packages. Other than these instances, the largest obstacles to using simulation packages were found to be the manpower required and the complexity of constructing a model. Continuing research efforts and increasing computer speeds are expected to resolve the former issues. Both of the latter concerns are alleviated by the approach presented herein. Within the approach framework detailed in this thesis, particular emphasis is given to the calibration aspects of constructing a microscopic simulation model. Like the simulation process as a whole, calibration is both an art and a science, and relies on sound engineering judgement rather than indiscriminate, formulaic processes. / Master of Science
39

Informing Colorectal Cancer Screening In Northern Canada Using Participatory Simulation Modeling

Smith, Heather Anne 05 October 2020 (has links)
Background: Mortality from colorectal cancer (CRC) in the Northwest Territories (NWT), a northern region of Canada, is nearly double the national rate. While mortality could be reduced with greater adherence to CRC screening, this requires colonoscopy access which is limited, and difficult to predict in a complex remote health system. Simulation modeling has been used to plan CRC screening but the impact on decision-making and utility in complex remote health system is unclear. Aim: This thesis aims to estimate the colonoscopy requirements and outcomes of CRC screening in the NWT using simulation modeling in a way that will inform feasible patient-centered strategies to enhance screening. Methods: We conducted a systematic review of the validity and utility of simulation modeling in CRC screening delivery (Chapter 1, 2). Next, a retrospective cohort study of CRC screening participation and outcomes between 2014-2019 was conducted (Chapter 3). We used this data and the findings of the systematic review to inform our participatory simulation modeling approach (Chapter 4). With end-users of the simulation model (clinicians, administrators, and patients), we revised an existing simulation model, OncoSim-CRC, to estimate the resource requirements and outcomes of various strategies to deliver a CRC screening program in the NWT. Each scenario model was run for 500 million cases and model validity was assessed. To enhance ongoing collaboration, we shared the concepts of a Communities of Practice (CoP) framework with stakeholders and assisted in generating consensus on priorities for a CoP to address (Chapter 5). Results: The systematic review showed that simulation models have been used to generate evidence critical to informing decision making for a broad range of decisions related to CRC screening delivery. However, the impact of these models on decision making, end-user engagement, and model validity were rarely described. In the retrospective cohort study, we observed that fecal immunohistochemical test(FIT)-based CRC screening did not appear to prevent CRC or provide earlier detection, but did result in more frequent positive pathology results than anticipated for average risk screening. Factors associated with this include long wait times for colonoscopy, over 1 in 3 FIT positive individuals had clinical signs and symptoms of CRC, and higher relative risk of advanced neoplasia among indigenous individuals. These findings and the involvement of end-users, informed the simulation model study. Under the parameters of the model, we estimate that colonoscopy demand with a CRC screening program would surpass capacity within 1-2 years, and continue to increase over the next 10-15 years due to adenoma surveillance. If this colonoscopy demand is met, we estimate screen detected cancers would increase by 110%, and clinically detected cases reduce by 26%. Increasing the phase-in period or revising adenoma follow-up guidelines would reduce demand and still improve cancer detection and prevention. A framework for a CoP, and consensus on priorities among stakeholders were established. Conclusion: Participatory simulation modeling was a useful method of informing CRC screening delivery in a remote northern population. The simulated scenarios provide decision-makers with strategies to enhance programmatic screening while conserving colonoscopy resources. The findings of this thesis helps to characterize the current outcomes of CRC screening in the NWT, and identifies opportunities to improve CRC screening effectiveness for a remote and, largely indigenous population.
40

Using Computer Simulation Modeling To Evaluate The Bioterrorismresponse Plan At A Local Hospital Facility

Bebber, Robert 01 January 2007 (has links)
The terrorist attacks of September 11th, 2001 and the subsequent anthrax mail attack have forced health care administrators and policy makers to place a new emphasis on disaster planning at hospital facilities--specifically bioterrorism planning. Yet how does one truly "prepare" for the unpredictable? In spite of accreditation requirements, which demand hospitals put in to place preparations to deal with bioterrorism events, a recent study from the General Accounting Office (GAO) concluded that most hospitals are still not capable of dealing with such threats (Gonzalez, 2004). This dissertation uses computer simulation modeling to test the effectiveness of bioterrorism planning at a local hospital facility in Central Florida, Winter Park Memorial Hospital. It is limited to the response plan developed by the hospital's Emergency Department. It evaluates the plan's effectiveness in dealing with an inhalational anthrax attack. Using Arena computer simulation software, and grounded within the theoretical framework of Complexity Science, we were able to test the effectiveness of the response plan in relation to Emergency Department bed capacity. Our results indicated that the response plan's flexibility was able to accommodate an increased patient load due to an attack, including an influx of the "worried well." Topics of future work and study are proposed.

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