Dissertations / Theses: 'Sewer design Mathematical models'

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Stovold, Matthew R. "Modeling urban stormwater disposal systems for their future management and design." University of Western Australia. School of Environmental Systems Engineering, 2007. http://theses.library.uwa.edu.au/adt-WU2007.0111.

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[Truncated abstract]This thesis investigates aspects of urban stormwater modeling and uses a small urban catchment (NE38) located in the suburb of Nedlands in Perth, Western Australia to do so. The MUSIC (Model for Urban Stormwater Improvement Conceptualisation) model was used to calibrate catchment NE38 using measured stormwater flows and rainfall data from within the catchment. MUSIC is a conceptual model designed to model stormwater flows within urban environments and uses a rainfall-runoff model adapted to generate results at six minute time steps. Various catchment scenarios, including the use of porous asphalt as an alternative road surface, were applied to the calibrated model to identify effective working stormwater disposal systems that differ from the current system. Calibrating catchment NE38 using the MUSIC model was attempted and this involved matching modeled stormwater flows to stormwater flows measured at the catchment drainage point. This was achieved by measuring runoff contributing areas (roads) together with rainfall data measured from within the catchment and altering the seepage constant parameter for all roadside infiltration sumps. ... The MUSIC model generated future scenario outcomes for alternative stormwater disposal systems that displayed similar or improved levels of performance with respect to the current system. The following scenarios listed in increasing order of effectiveness outline future stormwater disposal systems that may be considered in future urban design. 1. 35% porous asphalt application with no sumps in 2036 2. 35% porous asphalt application with no sumps in 2064 3. 68% porous asphalt application with no sumps in 2036 4. 68% porous asphalt application with no sumps in 2064. Future scenarios using the current stormwater disposal system (with roadside infiltration sumps) with porous asphalt were also run. These scenarios reduced stormwater runoff and contaminant loading on the catchment drainage point however the inclusion of a roadside infiltration sump system may not appeal to urban designers due to the costs involved with this scenario. Climate change will affect the design of future stormwater disposal systems and thus, the design of these systems must consider a rainfall reducing future. Based on the findings of this thesis, current stormwater runoff volumes entering catchment drainage points can be reduced together with contaminant loads in urban environments that incorporate porous asphalt with a stormwater disposal design system that is exclusive of roadside infiltration sumps.

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Wu, Guangxi. "Sensitivity and uncertainty analysis of subsurface drainage design." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/28529.

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Literature on subsurface drainage theories, determination of drainage parameters, and analysis approaches of uncertainty was reviewed. Sensitivity analysis was carried out on drain spacing equations for steady state and nonsteady state, in homogeneous soils and in layered soils. It was found that drain spacing is very sensitive to the hydraulic conductivity, the drainage coefficient, and the design midspan water table height. Spacing is not sensitive to the depth of the impermeable layer and the drain radius. In transient state, spacing is extremely sensitive to the midspan water table heights if the water table fall is relatively small. In that case steady state theory will yield more reliable results and its use is recommended. Drain spacing is usually more sensitive to the hydraulic conductivity of the soil below the drains than to that of the soil above the drains. Therefore, it is desirable to take samples from deeper soil when measuring hydraulic conductivity. A new spacing formula was developed for two-layered soils and a special case of three-layered soils with drains at the interface of the top two layers. This equation was compared with the Kirkham equation. The new formula yields spacings close to the Kirkham equation if the hydraulic conductivity of the soil above the drains is relatively small; otherwise, it tends to give more accurate results. First and second order analysis methods were employed to analyze parameter uncertainty in subsurface drainage design. It was found that conventional design methods based on a deterministic framework may result in inadequate spacing due to the uncertainty involved. Uncertainty may be incorporated into practical design by using the simple equations and graphs presented in this research; the procedure was illustrated through an example. Conclusions were drawn from the present study and recommendations were made for future research.
Applied Science, Faculty of
Graduate

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Pavlík, Ondřej. "Matematické modelování retenčních objektů městského odvodnění." Doctoral thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-233818.

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This work deals with the use of 3D mathematical models of fluid in water management practice. Using 3D mathematical model was assessed retention tank Jeneweinova, which is situated on a sewer network of the city of Brno and is an important object of urban drainage. Retention basin designed to keep overflow from CSO chambers to Svratka and Svitavský náhon during storm events. Retention tank Jeneweinova is suitable for the assessment, because tank was designed bassed the Master Plan drainage of Brno using 1D mathematical model. Another factor was the physical model, which was build in LVV Vin FAST BUT. And finally, near the retention tank will be installed measurement on the sewerage network, which will be able to verify the results whitch has been predicted in this work. Mathematical model of retention tanks Jeneweinova was build in software FLOW-3D. FLOW-3D is a general purpose CFD (Computational Fluid Dynamics) software for flow of fluid in steady and unsteady mode and uses computational techniques to solve the equations of motion of fluids. This software is mainly used for the calculation of hydraulic fluids, gas flow and heat transfer simulations. Results from 3D mathematical model has been compared with the values in the physical and 1D mathematical model.

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Zhang, Bo. "Design, modelling and simulation of a novel micro-electro-mechanical gyroscope with optical readouts." Thesis, Cape Peninsula University of Technology, 2007. http://hdl.handle.net/20.500.11838/1101.

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Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2007
Micro Electro-Machnical Systems (MEMS) applications are fastest development technology present. MEMS processes leverage mainstream IC technologies to achieve on chip sensor interface and signal processing circuitry, multi-vendor accessibility, short design cycles, more on-chip functions and low cost. MEMS fabrications are based on thin-film surface microstructures, bulk micromaching, and LIGA processes. This thesis centered on developing optical micromaching inertial sensors based on MEMS fabrication technology which incorporates bulk Si into microstructures. Micromachined inertial sensors, consisting of the accelerometers and gyroscopes, are one of the most important types of silicon-based sensors. Microaccelerometers alone have the second largest sales volume after pressure sensors, and it is believed that gyroscopes will soon be mass produced at the similar volumes occupied by traditional gyroscopes. A traditional gyroscope is a device for measuring or maintaining orientation, based on the principle of conservation of angular momentum. The essence of the gyroscope machine is a spinning wheel on an axle. The device, once spinning, tends to resist changes to its orientation due to the angular momentum of the wheel. In physics this phenomenon is also known as gyroscopic inertia or rigidity in space. The applications are limited by the huge volume. MEMS Gyroscopes, which are using the MEMS fabrication technology to minimize the size of gyroscope systems, are of great importance in commercial, medical, automotive and military fields. They can be used in cars for ASS systems, for anti-roll devices and for navigation in tall buildings areas where the GPS system might fail. They can also be used for the navigation of robots in tunnels or pipings, for leading capsules containing medicines or diagnostic equipment in the human body, or as 3-D computer mice. The MEMS gyroscope chips are limited by high precision measurement because of the unprecision electrical readout system. The market is in need for highly accurate, high-G-sustainable inertial measuring units (IMU's). The approach optical sensors have been around for a while now and because of the performance, the mall volume, the simplicity has been popular. However the production cost of optical applications is not satisfaction with consumer. Therefore, the MEMS fabrication technology makes the possibility for the low cost and micro optical devices like light sources, the waveguide, the high thin fiber optical, the micro photodetector, and vary demodulation measurement methods. Optic sensors may be defined as a means through which a measurand interacts with light guided in an optical fiber (an intrinsic sensor) or guided to (and returned from) an interaction region (an extrinsic sensor) by an optical fiber to produce an optical signal related to the parameter of interest. During its over 30 years of history, fiber optic sensor technology has been successfully applied by laboratories and industries worldwide in the detection of a large number of mechanical, thermal, electromagnetic, radiation, chemical, motion, flow and turbulence of fluids, and biomedical parameters. The fiber optic sensors provided advantages over conventional electronic sensors, of survivability in harsh environments, immunity to Electro Magnetic Interference (EMI), light weight, small size, compatibility with optical fiber communication systems, high sensitivity for many measurands, and good potential of multiplexing. In general, the transducers used in these fiber optic sensor systems are either an intensity-modulator or a phase-modulator. The optical interferometers, such as Mach-Zehnder, Michelson, Sagnac and Fabry-Perot interferometers, have become widely accepted as a phase modulator in optical sensors for the ultimate sensitivity to a range of weak signals. According to the light source being used, the interferometric sensors can be simply classified as either a coherence interferometric sensor if a the interferometer is interrogated by a coherent light source, such as a laser or a monochromatic light, or a lowcoherence interferometric sensor when a broadband source a light emitting diode (LED) or a superluminescent diode (SLD), is used. This thesis proposed a novel micro electro-mechanical gyroscope system with optical interferometer readout system and fabricated by MEMS technology, which is an original contribution in design and research on micro opto-electro-mechanical gyroscope systems (MOEMS) to provide the better performances than the current MEMS gyroscope. Fiber optical interferometric sensors have been proved more sensitive, precision than other electrical counterparts at the measurement micro distance. The MOMES gyroscope system design is based on the existing successful MEMS vibratory gyroscope and micro fiber optical interferometer distances sensor, which avoid large size, heavy weight and complex fabrication processes comparing with fiber optical gyroscope using Sagnac effect. The research starts from the fiber optical gyroscope based on Sagnac effect and existing MEMS gyroscopes, then moving to the novel design about MOEMS gyroscope system to discuss the operation principles and the structures. In this thesis, the operation principles, mathematics models and performances simulation of the MOEMS gyroscope are introduced, and the suitable MEMS fabrication processes will be discussed and presented. The first prototype model will be sent and fabricated by the manufacture for the further real time performance testing. There are a lot of inventions, further research and optimize around this novel MOEMS gyroscope chip. In future studying, the research will be putted on integration three axis Gyroscopes in one micro structure by optical sensor multiplexing principles, and the new optical devices like more powerful light source, photosensitive materials etc., and new demodulation processes, which can improve the performance and the interface to co-operate with other inertial sensors and navigation system.

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Viriththamulla, Gamage Indrajith. "Mathematical programming models and heuristics for standard modular design problem." Diss., The University of Arizona, 1991. http://hdl.handle.net/10150/185431.

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In this dissertation, we investigate the problem of designing standard modules which can be used in a wide variety of products. The basic problem is: given a set of parts and products, and a list of the number of each part required in each product, how do we group parts into modules and modules into products to minimize costs and satisfy requirements. The design of computers, electronic equipments, tool kits, emergency vehicles and standard military groupings are among the potential applications for this work. Several mathematical programming models for modular design are developed and the advantages and weaknesses of each model have been analyzed. We demonstrate the difficulties, due to nonconvexity, of applying global optimization methods to solve these mathematical models. We develop necessary and sufficient conditions for satisfying requirements exactly, and use these results in several heuristic methods. Three heuristic structures; decomposition, sequential local search, and approximation, are considered. The decomposition approach extends previous work on modular design problems. Sequential local search uses a standard local solution routine (MINOS) and sequentially adds cuts on the objective function to the original model. The approximation approach uses a "least squares" relaxation to find upper and lower bounds on the objective of the optimal solution. Computational results are presented for all three approaches and suggest that the approximation approach performs better than the others (with respect to speed and solution quality). We conclude the dissertation with a stochastic variation of the modular design problem and a solution heuristic. We discuss an approximation model to the continuous formulation, which is a geometric programming model. We develop a heuristic to solve this problem using monotonicity properties of the functions. Computational results are given and compared with an upper bound.

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Malone, Brett. "Multidisciplinary optimization in aircraft design using analysis technology models." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-10102009-020042/.

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Kim, In-Gyu. "Essays on the design of procurement auctions." Diss., Virginia Tech, 1992. http://hdl.handle.net/10919/40184.

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This dissertation is a collection of articles on the design of procurement auctions. Chapter 1 provides a primer to the subsequent three essays. Rather than addressing all the issues involved, it illustrates some basic concepts about auctions, both institutionally and theoretically. It also highlights some problems that arise when auction theory is applied to procurement auctions.
Ph. D.

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Waterhouse, Timothy Hugh. "Optimal experiemental design for nonlinear and generalised linear models /." [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18919.pdf.

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Mirjalili, Vahid. "Modelling the structural efficiency of cross-sections in limited torsion stiffness design." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=99780.

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Most of the current optimization techniques for the design of light-weight structures are unable to generate structural alternatives at the concept stage of design. This research tackles the challenge of developing an optimization method for the early stage of design. The main goal is to propose a procedure to optimize material and shape of stiff shafts in torsion.
Recently introduced for bending stiffness design, shape transformers are presented in this thesis for optimizing the design of shafts in torsion. Shape transformers are geometric parameters defined to classify shapes and to model structural efficiency. The study of shape transformers are centered on concept selection in structural design. These factors are used to formulate indices of material and shape selection for minimum mass design. An advantage of the method of shape transformers is that the contribution of the shape can be decoupled from the contribution of the size of a cross-section. This feature gives the designer insight into the effects that scaling, shape, as well as material have on the overall structural performance.
Similar to the index for bending, the performance index for torsion stiffness design is a function of the relative scaling of two cross-sections. The thesis examines analytically and graphically the impact of scaling on the torsional efficiency of alternative cross-sections. The resulting maps assist the selection of the best material and shape for cross-sections subjected to dimensional constraints. It is shown that shape transformers for torsion, unlike those for bending, are generally function of the scaling direction.
The efficiency maps ease the visual contrast among the efficiency of open-walled cross-sections and that of close-walled cross-sections. As expected, the maps show the relative inefficiency of the former compared to the latter. They can also set the validity range of thin- and thick-walled theory in torsion stiffness design. The analytical results are validated with the numerical data obtained from ANSYS to guarantee the consistency of the models. The thesis concludes with three case studies that demonstrate the method.

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LeBlanc, Andrew Roland. "Engineering design decomposition." Thesis, Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/16044.

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Murphy, Ryan John. "Mechanochemical and experimental models in mathematical biology." Thesis, Queensland University of Technology, 2022. https://eprints.qut.edu.au/228428/1/Ryan%20John_Murphy_Thesis.pdf.

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Experiments that probe epithelial tissue dynamics, cell competition, and tumour growth are fundamental to understand processes in developmental biology, cancer progression and treatment. However, interpreting complex biological experiments is challenging. To address this challenge, we develop and use a range of mathematical models. First, we focus on epithelial tissue dynamics. Second, we use real-time cell cycle imaging to reveal the structure of growing tumour spheroids. We then revisit the seminal Greenspan tumour growth model and use statistical analysis to quantitatively connect it to experimental data for the first time to reveal experimental design choices that lead to reliable biological insight.

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Wong, Chi-kwong, and 黃志光. "Lane-based optimization method for traffic signal design." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B31246096.

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Su, Wei, and 蘇薇. "Partner selection and production-distribution planning for the design of optimal supply chain networks." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B41757853.

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Marston, Matthew C. "Game based design : a game theory based approach to engineering design." Diss., Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/15877.

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Larson, Bradley Jared. "Mathematical Framework for Early System Design Validation Using Multidisciplinary System Models." BYU ScholarsArchive, 2012. https://scholarsarchive.byu.edu/etd/3000.

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A significant challenge in the design of multidisciplinary systems (e.g., airplanes, robots, cell phones) is to predict the effects of design decisions at the time these decisions are being made early in the design process. These predictions are used to choose among design options and to validate design decisions. System behavioral models, which predict a system's response to stimulus, provide an analytical method for evaluating a system's behavior. Because multidisciplinary systems contain many different types of components that have diverse interactions, system behavioral models are difficult to develop early in system design and are challenging to maintain as designs are refined. This research develops methods to create, verify, and maintain multidisciplinary system models developed from models that are already part of system design. First, this research introduces a system model formulation that enables virtually any existing engineering model to become part of a large, trusted population of component models from which system behavioral models can be developed. Second, it creates a new algorithm to efficiently quantify the feasible domain over which the system model can be used. Finally, it quantifies system model accuracy early in system design before system measurements are available so that system models can be used to validate system design decisions. The results of this research are enabling system designers to evaluate the effects of design decisions early in system design, improving the predictability of the system design process, and enabling exploration of system designs that differ greatly from existing solutions.

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Browning, Alexander P. "Stochastic mathematical models of cell proliferation assays." Thesis, Queensland University of Technology, 2017. https://eprints.qut.edu.au/110808/1/Alexander_Browning_Thesis.pdf.

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Cell proliferation assays are routinely used to study collective cell behaviour, and can be interpreted with mathematical models. In this thesis, we apply a computational Bayesian technique to calibrate stochastic discrete mathematical models of cell migration and cell proliferation in the context of a cell proliferation assay. Initially, we use a lattice-based model to explore the optimal duration of a cell proliferation assay. Next, we estimate the parameters in a lattice-free model using three independent experimental data sets. Our model is able to both describe and predict the evolution of the population and spatial structure in a cell proliferation assay.

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Thompson, Mery H. "Optimum experimental designs for models with a skewed error distribution with an application to stochastic frontier models /." Connect to e-thesis, 2008. http://theses.gla.ac.uk/236/.

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Thesis (Ph.D.) - University of Glasgow, 2008.
Ph.D. thesis submitted to the Faculty of Information and Mathematical Sciences, Department of Statistics, 2008. Includes bibliographical references. Print version also available.

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Tang, Baobao. "Development of Mathematical and Computational Models to Design Selectively Reinforced Composite Materials." Thesis, University of Louisiana at Lafayette, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10163313.

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Different positions of a material used for structures experience different stresses, sometimes at both extremes, when undergoing processing, manufacturing, and serving. Taking the three-point bending as an example, the plate experiences higher stress in the middle span area and lower stress in both sides of the plate. In order to ensure the performance and reduce the cost of the composite, placement of different composite material with different mechanical properties, i.e. selective reinforcement, is proposed.

Very few study has been conducted on selective reinforcement. Therefore, basic understanding on the relationship between the selective reinforcing variables and the overall properties of composite material is still unclear and there is still no clear methodology to design composite materials under different types of loads.

This study started from the analysis of composite laminate under three point bending test. From the mechanical analysis and simulation result of homogeneously reinforced composite materials, it is found that the stress is not evenly distributed on the plate based on through-thickness direction and longitudinal direction. Based on these results, a map for the stress distribution under three point bending was developed. Next, the composite plate was selectively designed using two types of configurations. Mathematical and finite element analysis (FEA) models were built based on these designs. Experimental data from tests of hybrid composite materials was used to verify the mathematical and FEA models. Analysis of the mathematical model indicates that the increase in stiffness of the material at the top and bottom surfaces and middle-span area is the most effective way to improve the flexural modulus in three point bending test. At the end of this study, a complete methodology to perform the selective design was developed.

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Butler, Renee J. "Supply chain design for new products." Diss., Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/25652.

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朱國基 and Kwok-kei Chu. "Design and control of a six-legged mobile robot." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31225895.

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Hernandez, Gabriel. "A probabilistic-based design approach with game theoretical representations of the enterprise design process." Thesis, Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/33422.

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Banach, Antoni StanisŁaw. "Feedback design for nonlinear distributed-parameter systems by extended linearization." Diss., Virginia Tech, 1992. http://hdl.handle.net/10919/39429.

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A feedback design procedure known as extended linearization consists in replacing a mathematical model of a nonlinear dynamical system with its family of linearizations, parametrized by the operating point, and then combining feedback gains designed for representatives of the family into a single nonlinear feedback law. The principles of the procedure, applicable both to lumped-parameter and distributed-parameter systems, are discussed at the outset. The development shows limits on feedback laws that can be designed, as well as nonuniqueness of solutions, inherent in the method.
Ph. D.

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Zhang, Yang. "Advances in LTL load plan design." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/34712.

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A load plan specifies how freight is routed through a linehaul terminal network operated by a less-than-truckload (LTL) carrier. Determining the design of the load plan is critical to effective operations of such carriers. This dissertation makes contributions in modeling and algorithm design for three problems in LTL load plan design: (1) Refined execution cost estimation. Existing load plan design models use approximations that ignore important facts such as the nonlinearity of transportation costs with respect to the number of trailers, and empty travel beyond what is required for trailer balance that results from driver rules. We develop models that more accurately capture key operations of LTL carriers and produce accurate operational execution costs estimates; (2) Dynamic load planning. Load plans are traditionally revised infrequently by LTL carriers due to the difficulty of solving the associated optimization problem. Technological advances have now enabled carriers to consider daily load plan updates. We develop technologies that efficiently and effectively adjust a nominal load plan for a given day based on the actual freight to be served by the carrier. We present an integer programming based local search procedure, and a greedy randomized adaptive search heuristic; and (3) Stochastic load plan design. Load plan design models commonly represent origin-destination freight volumes using average demands, which do not describe freight volume fluctuations. We investigate load plan design models that explicitly utilize information on freight volume uncertainty and design load plans that most cost-effectively deal with varying freight volumes and lead to the lowest expected cost. We present a Sample Average Approximation approach and a variant of the method for solving the stochastic integer programming formulations.

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Smith, Ernest Price. "An optimal replacement-design model for a reliable water distribution network system." Diss., Virginia Tech, 1994. http://hdl.handle.net/10919/37455.

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Fett, Elise H. 1962. "AN INTEGRATED PROGRAM FOR THE DESIGN OF GROUP PILE SYSTEMS." Thesis, The University of Arizona, 1987. http://hdl.handle.net/10150/276410.

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Yang, Dong-Shan. "Deformation-based seismic design models for waterfront structures." Thesis, online access from Digital Dissertation Consortium access full-text, 1999. http://libweb.cityu.edu.hk/cgi-bin/er/db/ddcdiss.pl?9933214.

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Lai, Lin-Ying. "Suboptimal period design for a maneuvering missile to evade tracking filters." Diss., Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/53564.

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The engagement between an antiship missile and a ship’s defense system is investigated. The missile is equipped with proportional navigation guidance for homing in on its ship target. The ship’s defense system consists of a radar, an estimation system (the extended Kalman filter and the “jump filter” are used), and a gun system. The performance index is defined as the estimated number of hits (EHITS) of projectiles on the missile. The main objective of this dissertation is to determine maneuvering periods for the missile which minimize the EHITS to evade the ship’s gunfire under different engagement conditions. The maneuvering periods are design parameters in the missile’s controls of both the vertical and the horizontal planes. The engagement conditions are the follows: the maximum amplitude of the maneuvering functions, the homing in position of the missile on the ship, the measurement noise condition of the ship’s radar, and the missile’s model assumed in the ship’s filters. The missile’s control functions considered are periodic and of specific types (sinusoidal, square and sawtooth waveforms); therefore, the periods which minimize the EHITS in this study are suboptimal for the general engagement problem. Two methods are used to obtain the suboptimal periods: one is the ”brute force" method of computing the EHITS for certain equally spaced periods, the other uses an optimization software to search for the minimum point. The results show that the curve of EHITS vs. period is monotonically decreasing until it reaches a minimum point. The optimal period increases with an increase in measurement noise. Among the three waveforms used, the square wave gives the smallest optimal period and the sawtooth wave gives the largest one. The sinusoidal waveform with the period of 1.9 seconds is recommended. We consider the missile's performance against a perfect radar, a modern radar, and an earlier model radar. The optimum EHITS resulting from the optimal periods are between two and three EHITS for all three radars considered.
Ph. D.

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Jiang, Yu, and 姜宇. "Reliability-based transit assignment : formulations, solution methods, and network design applications." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/207991.

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Du, Plessis Sydney Charles. "Investigation of process parameters and development of a mathematical model for the purposes of control design and implementation for a wastewater treatment process." Thesis, Cape Peninsula University of Technology, 2009. http://hdl.handle.net/20.500.11838/1194.

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Thesis (DTech (Electrical Engineering))--Cape Peninsula University of Technology, 2009
The problem for effective and optimal control of wastewater treabnent plants is very important recently because of the increased requirements to the qualitY of the effluent The activated sludge process is a type of wastewater process characterized with complex dynamics and because of this proper control design and implementation strategies are necessary and important for its operation. Since the early seventies, when a major leap forward was made by the widespread introduction of dissolved oxygen control, little progress has been made. The most critical phase in the solution of any control problem is the modelling stage. The primary building block of any modem control exercise is to construct and identify a model for the system to be controlled. The existing full Activated Sludge Model 1 (ASM1) and especially University of Cape Town (UCT) models of the biological processes in the activated sludge process, called in the thesis biological models, are highly complex because they are characterised with a lot of variables that are difficult to be measured on-line, complex dependencies and nonlinear interconnections between the biological variables, many kinetic parameters that are difficult to be determined, . different time scales for the process dynamics. The project considers reduction of the impact of the complexity of the process model over the methods for control design and proposes a solution to the above difficulties by development of a reduced model with small number of variables, but still with the same characteristics as the original full model for the purposes of real time.

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Roy, Roger A. "An Application of Landscape Design to Student Academic Success." Fogler Library, University of Maine, 2006. http://www.library.umaine.edu/theses/pdf/RoyRA2006.pdf.

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Xu, Li Da. "Fuzzy multiobjective mathematical programming in economic systems analysis: design and method." PDXScholar, 1986. https://pdxscholar.library.pdx.edu/open_access_etds/471.

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Economic systems analysis is a systems analysis technique of setting out the factors that have to be taken into account in making economic systems decisions. The inquiring and operational systems of the technique are almost exclusively designed for well-structured systems. In review of economic systems analysis against systems thinking, there is a growing tendency to discard the analytical approach as inappropriate for dealing with an ill-structured issue. Therefore, economic systems analysis needs both the inquiring and operational systems which are appropriate for ill-structured systems. The foregoing leads to the introduction of an extensive methodology. Mainly, the weakness of economic systems analysis methodology can be traced to the philosophical paradigm upon which the technique is based. In this study, four main aspects of both the inquiring and operational systems of economic systems analysis are being explored: (1) A new philosophical paradigm is proposed as the foundation of general methodology in place of the traditional Newtonian-Kantian inquiring system. (2) The new philosophical paradigm needs new problem formulation and analysis space; therefore, a multidimensional, synergetic, and autopoietic model is proposed for systems synthesis and systems analysis. (3) The new philosophical paradigm is characterized as a Singerian inquiry, and as a result, Marglin's multiobjective analysis is replaced by a Singerian multiobjective analysis. (4) Markov communication theory and fuzzy sets theory are proposed as tools for handling complexity. Markov communication theory and fuzzy sets theory are introduced for systems design and multiple objective analysis. This study reports on the first application of a Singerian fuzzy multiobjective mathematical algorithm in economic systems analysis, concluding that fuzzy systems theory, especially Markov communication theory, can realize approximate reasoning in economic systems analysis. Fuzzy modeling offers a deeper understanding of complexity and a means of expressing the insights that result from that understanding; moreover, it provides a means of incorporating subjectivity and adaptation. Therefore, fuzzy modeling increases the validity of the systems approach for dealing with ill-structured systems. The proposed method represents an important theoretical improvement of Marglin's approach. The results, however, also hold practical importance, for they are of practical interest to systems analysts who would improve systems design and multiobjective analysis.

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Correia, Sara Alexandra Chanoca. "Development of improved mathematical models for the design and control of gas-fired furnaces." Thesis, University of South Wales, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369080.

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Bardhan, Jaydeep Porter 1978. "Efficient numerical algorithms for surface formulations of mathematical models for biomolecule analysis and design." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/37897.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2006.
Includes bibliographical references (p. 179-183).
This thesis presents a set of numerical techniques that extend and improve computational modeling approaches for biomolecule analysis and design. The presented research focuses on surface formulations of modeling problems related to the estimation of the energetic cost to transfer a biomolecule from the gas phase to aqueous solution. The thesis discusses four contributions to modeling biomolecular interactions. First, the thesis presents an approach to allow accurate discretization of the most prevalent mathematical definitions of the biomolecule-solvent interface; also presented are a number of accurate techniques for numerically integrating possibly singular functions over the discretized surfaces. Such techniques are essential for solving surface formulations numerically. The second part of the thesis presents a fast multiscale numerical algorithm, FFTSVD, that efficiently solves large boundary-element method problems in biomolecule electrostatics. The algorithm synthesizes elements of other popular fast algorithms to achieve excellent efficiency and flexibility. The third thesis component describes an integral-equation formulation and boundary-element method implementation for biomolecule electrostatic analysis.
(cont.) The formulation and implementation allow the solution of complicated molecular topologies and physical models. Furthermore, by applying the methods developed in the first half of the thesis, the implementation can deliver superior accuracy for competitive performance. Finally, the thesis describes a highly efficient numerical method for calculating a biomolecular charge distribution that minimizes the free energy' change of binding to another molecule. The approach, which represents a novel PDE-constrained methodology, builds on well-developed physical theory. Computational results illustrate not only the method's improved performance but also its application to realistic biomolecule problems.
by Jaydeep Porter Bardhan.
Ph.D.

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Mishra, Sharmistha. "Using mathematical models to characterize HIV epidemics for the design of HIV prevention strategies." Thesis, Imperial College London, 2014. http://hdl.handle.net/10044/1/24913.

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Since 2000, we have been trying to characterize and classify HIV epidemics to guide the strategic design of HIV prevention policies and focus HIV programmes and resource allocation by a regions' epidemic type. We have used arbitrary thresholds of HIV prevalence across different risk-groups in a given population, 'static' mathematical models and classical epidemiological measures of the population attributable fraction that do not account for chains of transmission. As a result, these traditional approaches could be missing the underlying transmission dynamics and the role of key populations - such as female sex workers and their clients - on HIV spread. In this thesis, I build on a growing paradigm shift on how we should re-classify HIV epidemics based on the epidemiological features that lead to HIV emergence and persistence (i.e. the 'epidemic drivers' that influence the basic reproductive ratio, R0). I examine the extent to which our traditional approaches have been underestimating the contribution of sex work to HIV spread and likely misclassifying epidemic type by developing dynamic mathematical models of HIV transmission and simulating a large number of plausible 'synthetic' HIV epidemics. I then develop - as proof-of-concept - a novel algorithm to diagnose epidemic type using these synthetic epidemics and glean the key epidemiological data that would be most useful to help distinguish between 'epidemic drivers', and therefore would be most useful to collect as part of HIV surveillance and future empirical research.

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O'Reilly, Małgorzata Marzena. "Necessary conditions for the variant optimal design of linear consecutive systems." Title page, contents and summary only, 2001. http://web4.library.adelaide.edu.au/theses/09PH/09pho668.pdf.

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"October 2001." Bibliography: leaves 99-103. Establishes several sets of conditioning relating to the variant optimal deign of linear consecutive-k-out-of-n systems and includes a review of existing research in the theory of variant optimal design of linear consecutive-k-out-of-n systems.

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Mason, Brian H. "Analysis and design of composite curved frames." Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-06102009-063304/.

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Sen, Sagar. "A model-driven approach to design engineered physical systems /." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=101173.

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The constant growth in complexity of engineered physical (electrical, mechanical etc.) systems has led to the development of software tools to store and reuse design knowledge to simplify the creation of such systems. Models that encode structure and behaviour of components in the system are currently being developed based on the techniques prescribed by Model Driven Engineering (MDE). We use MDE concepts to develop appropriate modelling formalisms to allow creation of models of a target Engineered Physical System ( EPS) at different levels of abstraction. Each level of abstraction presents a certain view of the EPS to a domain expert in the development team. For instance, a high-level view is suitable for a person in a managerial role. An engineer who deals with the same system at a lower level of abstraction develops a model using idealized physical components. A physicist's concern is the physical meaningfulness of the model. The physicist's model verifies if the model prescribed by the manager via the engineer adheres to the laws of conservation of energy and momentum. Finally, a mathematician or a computer scientist obtains a solution to the constrained equations imposed by the dynamical system by solving it analytically or numerically. This model usually takes the form of a set of Differential Algebraic Equations provided by the physicist.
We design model transformations to transform models from a high-level modelling language to lower-level language. We present visual Graph Grammar rules to perform these transformations. We start with a high-level representation of the physical system which is a model in the High-level Physical System Model modelling language. This model is transformed in subsequent steps to a set of trajectories that describe the state of the physical system over time. We show that this hierarchy of transformations to encode knowledge about physical systems drastically reduces design space size at the high-level of abstraction. We search the space of an example EPS using a design heuristic based randomized algorithm to determine the speedup in search due to reduction in the number of design variables.

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Ramachandran, Selvaraj. "Hypoid gear optimization." PDXScholar, 1992. https://pdxscholar.library.pdx.edu/open_access_etds/4419.

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A hypoid gear optimization procedure using the method of feasible directions has been developed. The objective is to reduce the gear set weight with bending strength, contact strength and facewidth-diametral pitch ratio as constraints. The objective function weight, is calculated from the geometric approximation of the volume of the gear and pinion. The design variables selected are number of gear teeth, diametral pitch, and facewidth. The input parameters for starting the initial design phase are power to be transmitted, speed, gear ratio, type of application, mounting condition, type of loading, and the material to be used. In the initial design phase, design parameters are selected or calculated using the standard available procedures. These selected values of design parameters are passed on to the optimization routine as starting points.

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LEE, SEUNG JOO. "RELIABILITY-BASED OPTIMAL STRUCTURAL AND MECHANICAL DESIGN." Diss., The University of Arizona, 1987. http://hdl.handle.net/10150/184136.

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Structural reliability technology provides analytical tools for management of uncertainty in all relevant design factors in structural and mechanical systems. Generally, the goal of analysis is to compute probabilities of failure in structural components or system having single or multiple failure mode. Alternately, modern optimization methods provide efficient numerical algorithms for locating optima, particularly in large-scale systems having prescribed deterministic constraints. Optimization procedure can accommodate random variables either directly in its objective function or as one of the primary constraints. The combination of elementary optimization and probabilistic design techniques is the subject of this study. Presented herein is a general strategy for optimization when the design factors are random variables and some or all of the constraints are probability statements. A literature review has indicated that optimization technology in a reliability context has not been fully explored for the general case of nonlinear performance functions and nonnormal variates associated multiple failure modes. This research focuses upon development of the theory to address this general problem. Because analysis algorithms are complicated, a computer code, program RELOPT, is constructed to automate the analysis. The objective function to be minimized is arbitrary, but would generally be the total expected lifetime costs including all initial costs as well as all costs associated with failure. Uncertainty is assumed to be possible in all design factors (including the factors to be determined), and they are modeled as random variables. In general, all of the constraints can be probability statements. The generalized reduce gradient (GRG) method was used for optimization calculations. Options for point probability calculations are first order reliability analysis using the Rackwitz-Fiessler (R-F) or advanced reliability analysis using Wu/FPI. For system reliability analysis either the first order Cornell's bounds or the second order Ditlevsen's bounds can be specified. Several examples are presented to illustrate the full range of capabilities of RELOPT. The program is validated by checking with independent and exact solutions. An example is provided which demonstrates that the cost of running RELOPT can be substantial as the size of the problem increases.

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Sun, Ximeng 1979. "A model-driven approach to scenario-based requirements engineering /." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=101655.

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A model-driven approach to scenario-based requirements engineering is proposed. The approach, which is based on Computer Automated Multi-Paradigm Modeling (CAMPaM), aims to improve the software process. A framework is given and implemented to reason about models of systems at multiple levels of abstraction, to transform between models in different formalisms, and to provide and evolve modeling formalisms.
The model-driven approach starts with modeling requirements of a system in scenario models and the subsequent automatic transformation to state-based behavior models. Then, either code can be synthesized or models can be further transformed into models with additional information such as explicit timing information or interactions between components. These models, together with the inputs (e.g., queries, performance metrics, test cases, etc.) generated directly from the scenario models, can be used for a variety of purposes, such as verification, analysis, simulation, animation and so on.
A visual modeling environment is built in AToM3 using Meta-Modeling and Model Transformation. It supports modeling in Sequence Diagrams, automatic transformation to Statecharts, and automatic generation of requirements text from Sequence Diagrams.
An application of the model-driven approach to the assessment of use cases for dependable systems is shown.

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譚熙嘉 and Hei-Ka Patrick Tam. "Optimization approaches to robust pole assignment in control system design." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B3123933X.

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Pang, Yong, and 龐勇. "Advance in two-dimensional RF pulse design and transmit SENSE." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B40887856.

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Campbell, William James. ""When Mathematical Activity Moves You"| An Exploration of the Design and Use of Purposefully Embodied Mathematical Activities, Models, Contexts, and Environments." Thesis, University of Colorado at Boulder, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10288604.

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This dissertation describes a mathematics curriculum and instruction design experiment involving a series of embodied mathematical activities conducted in two Colorado elementary schools Activities designed for this experiment include multi-scalar number line models focused on supporting students’ understanding of elementary mathematics. Realistic Mathematics Education (RME) served as a roadmap for the development of models and problem contexts during the design process, and maintained the focus on mathematics as human activity. Key ideas and insights from scholars who have employed embodied, enactive, ecological, multimodal, and inclusive materialist theories of mathematical activity/cognition on spatiality, human vision, and perception also informed the work. Departing from the sedentary approach to U.S. elementary school mathematics learning and instruction, the designed activities intentionally required students to use their bodies and tools in space to coordinate solutions to mathematical problems. As a design experiment, the research took place in two phases over the course of a year. Phase 1 occurred over 17 days in a suburban 2^nd grade public school classroom, and phase 2 consisted of six 55-minute clinical interviews with six student pairs from two 3^rd grade classrooms in an urban public school. Findings from this research included students using the designed models to support mathematical arguments and to increase levels of precision in their mathematical activity. Themes also emerged around the ways that students responded to affordances and constraints of the models, by shifting orientations, authority, and re-purposing and creating new tools. Multi-scalar mathematical models, activities, and activity spaces afforded novel and intentionally embodied ways for students to participate in model-centric mathematical activity.

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Bakkalbasi, Omer. "Flow path network design and layout configuration for material delivery systems." Diss., Georgia Institute of Technology, 1989. http://hdl.handle.net/1853/25617.

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Chen, Jou-Jun Robert. "Load and resistance factor design of shallow foundations for bridges." Thesis, Virginia Tech, 1989. http://hdl.handle.net/10919/44627.

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Load Factor Design (LFD), adopted by AASHTO in the mid-1970, is currently used for bridge superstructure design. However, the AASHTO specifications do not have any LFD provisions for foundations. In this study, a LFD format for the design of shallow foundations for bridges is developed.

Design equations for reliability analysis are formulated. Uncertainties in design parameters for ultimate and serviceability limit states are evaluated. A random field model is employed to investigate the combined inherent spatial variability and systematic error for serviceability limit state. Advanced first order second moment method is then used to compute reliability indices inherent in the current AASHTO specifications. Reliability indices for ultimate and serviceability limit states with different safety factors and dead to live load ratios are investigated. Reliability indices for ultimate limit state are found to be in the range of 2.3 to 3.4, for safety factors between 2 and 3. This is shown to be in good agreement with Meyerhof's conclusion (1970). Reliability indices for serviceability limit state are found to be in the range of 0.43 to 1.40, for ratios of allowable to actual settlement between 1.0 to 2.0. This appears to be in good agreement with what may be expected. Performance factors are then determined using target reliability indices selected on the basis of existing risk levels.

Master of Science

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Crane, Scott P. "Structural acoustic design optimization of cylinders using FEM/BEM." Thesis, Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/17699.

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Ibbotson, Scott Mechanical &amp Manufacturing Engineering Faculty of Engineering UNSW. "Analysing the critical design parameters for reuse." Awarded by:University of New South Wales. School of Mechanical and Manufacturing Engineering, 2006. http://handle.unsw.edu.au/1959.4/27354.

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Reuse of components as opposed to material recovery, recycling or disposal has been identified as one of the most efficient EOL strategies for products. The concept behind reuse is that some components and subassemblies have a design life that exceeds the life of the product itself. In order for reuse to be successfully implemented as an EOL strategy, a designer needs to incorporate into a product a philosophy of Design for Reuse (DfRe) at the early design stage. Reliable methods to assess the remaining life of used components based on a products usage life are also required. Furthermore, current industry practices and literature advocate that there is no methodology to decide which parameters need to be redesigned so as to change the life of a selected component to a desired level. The objective of this research is to develop a methodology to assess the reuse potential of product groups based on component failure mechanisms and their associated critical lifetime prediction design parameters. Utilising these clustered groups mathematical models were then developed to establish the useful life of the components for each clustered group. Finally, a means of equating useful life to design life was established and the relationship between, the failure mechanisms, critical lifetime prediction design parameters and design life were represented in graphical format. In order to achieve the proposed objective, Cluster analysis, in particular Group Technology (GT) and Hierarchical clustering were employed to group components with similar failure mechanisms. Following this, multiple linear regression was used to establish mathematical models based on condition monitoring data for each of the clustered groups and their related critical lifetime prediction design parameters. A sensitivity analysis was conducted using the mathematical models, in order to produce graphical relations between the useful life and design parameters of a product. The validity of the suggested methodology was tested on electric motors and a gearbox as both these components have demonstrated great reuse potential. The results demonstrate that the methodology can assist designers in estimating the design life and associated design parameters with great accuracy, and subsequently aiding in a stratagem for reuse.

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Kaczorowski, Przemyslaw Robert. "Thermal-based multi-objective optimal design of liquid cooled power electronic modules." Thesis, Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/16448.

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Chan, Chi-keung, and 陳志強. "Minimum bounding boxes and volume decomposition of CAD models." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B29947340.

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Williams, Christopher Bryant. "Platform design for customizable products and processes with non-uniform demand." Thesis, Available online, Georgia Institute of Technology, 2004:, 2003. http://etd.gatech.edu/theses/available/etd-04082004-180453/unrestricted/williams%5fchristopher%5fb%5f200312%5fms.pdf.

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Dissertations / Theses on the topic 'Sewer design Mathematical models'

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