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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

Design, performance and fit of fabrics for female body armour

Yang, Dan January 2011 (has links)
This thesis focuses on the development of a new technique which enables a novel type of front panel for female body armour to be engineered, providing female contour, high level protection, and therefore comfort in wearing. The traditional cutting and stitching method can be used to form a dome shape to accommodate the bust area but it gives rise to weakness against projectile impact at the seams. A novel type of fabric with the advantage in mouldability is needed as an alternative to the conventional plain woven fabric in making female body armour without the need of cutting or folding but ease in manufacture. Dome-shaped fabric and angle-interlock woven fabric are two potential candidates. The analysis and comparisons determine the selection of the fabric with superior dome depth which is more suitable for the female body armour application. Ballistic evaluations on the selected fabric were carried out from two aspects: the overall ballistic performance investigation and the parametric study. The result provided a better understanding of kinetic energy absorption capability of single-piece selected fabrics. Additionally, the ballistic performance of fabric panels was further evaluated in the factory in order to ensure the selected fabric could achieve the commercial requirement. After the investigations of mouldability and ballistic resistance of the selected fabric, a mathematical model was created, which determines the pattern geometry for the front panel of the female body armour. This mathematical model takes the body figure size and bra size as the input, and the output is the profile of the front panel of female body armour. This work enables the speedy creation of a front panel of the female body armour in the selected fabric. This is an important advance and a novel approach for making seamless female body armour with satisfactory ballistic performance.
32

Optimized Method of Estimating Mineral Reserves Using the O'Hara Mathematical Model for Underground Mining in Peru

Torres-Sanchez, V., Torres-Sanchez, V., Olivas-Maldonado, P., Diaz-Huaina, G., Raymundo-Ibanez, C., Perez, Moises 28 February 2020 (has links)
Peru / This research project is aimed at applying the proposed methodology to optimize the calculation of mining reserves using an empirical relationship for dilution, as proposed by O'Hara. This methodology uses three key parameters: dilution, mineral value, and total costs. In general, costs include mining costs, processing within plants, and administrative expenses related to producing a mineralized block. Similarly, to calculate the mineral value, studies on changes in mineral prices over the last 30 years were included to provide more representative values. The research was applied to mineralized block number 1000, which yielded positive results since dilution could be easily calculated using three key parameters: operating method, dip, and vein width. The dilution value of 12.25% was valid, as it was within the range of 10% to 23%. This range was considered based on other studies that apply this operating method. Then, the methodology was analyzed in three more settings, each represented by a mineralized block. The blocks assessed were 1001, 1002, and 1003, and the results indicated that the dilution found was acceptable at values of 18%, 19%, and 22%, respectively.
33

Development and Implementation of a P4 Parallel Through-the-Road Hybrid Electric Vehicle

Orr, Matthieu January 2023 (has links)
The increasing demand for sustainable transportation solutions has led to the rapid evolution of hybrid and electric vehicles. This thesis, undertaken as part of the EcoCAR Mobility Challenge, presents the development and implementation of a control system for a P4 parallel through-the-road hybrid electric vehicle. A comprehensive vehicle model was developed using MATLAB Simulink. This model was used to model overall vehicle performance and component-specific performance throughout the EcoCAR Mobility Challenge and served as the foundation for the subsequent stages of control system development. Extensive component and vehicle testing formed the crux of this thesis. These bench tests provide invaluable data that aided in the implementation of the component control loops into the MAC Team vehicle. On-road vehicle testing further refined the energy management strategy, drivability, and charge sustaining of the high voltage battery. The vehicle control system has 10 control modules that successfully operated the MAC Team vehicle for over 1500km on public roads. The methodologies and findings can guide future projects aiming to optimize hybrid vehicle performance. / Thesis / Master of Applied Science (MASc) / With hybrid electric vehicles and electric vehicles rising in popularity, the EcoCAR Mobility Challenge and its sponsors created an opportunity for McMaster University and 10 other universities across North America to modify a 2019 Chevrolet Blazer into a hybrid electric vehicle. This thesis focuses on the development of the control strategy for the McMaster University vehicle. A mathematical vehicle model was developed to run vehicle simulations in order to evaluate vehicle performance and the performance of individual components. Individual components were tested in order to develop control loops for these components. These control loops and other control modules were used during vehicle testing. On-road vehicle testing refined the vehicle control strategy evidenced by the over 1500km driven on public roads.
34

Multiscale Analysis of Void Coalescence in Ductile Metals

Jones, Matthew Kenneth 11 December 2004 (has links)
A mulitscale approach is used to model the coalescence of voids. At the microscale, cylindrical and spherical voids in nickel and the magnesium alloy AM60 are simulated through finite element analyses. The nickel cylindrical void simulations are compared to a set of experiments to validate this micromechanical finite element approach used to study void coalescence. At the macroscale, the coalescence portion of a microstructure-property material model is modified to reflect the behavior of three-dimensional spherical voids using results from the micromechanical simulations. An analysis of an automotive component illustrates the influence of void coalescence at the structural scale.
35

A dynamical model of campylobacteriosis in Ohio

Helba, Johanna H. 21 September 2017 (has links)
No description available.
36

MATHEMATICAL MODEL TO PREDICT THE SKIN DISPOSITION OF DEET AND OTHER VOLATILE COMPOUNDS

SANTHANAM, ARJUN 05 October 2004 (has links)
No description available.
37

Mathematical Model of Neurochemical Mechanisms in a Single GABA Neuron

Rodriguez, Evelyn January 2016 (has links)
No description available.
38

A Theoretical Model and Study of Mathematical Anxiety

Spilotro, Savannah January 2018 (has links)
The study of mathematical anxiety has seen an increased importance in the past few decades in the field of mathematical education. As this topic is of great interest in education research, this thesis investigates the previous contributions made by other researchers via a literature review of mathematical education papers. Furthermore, a literature review of mathematical models of learning is presented. In the hopes of closing the gap between these two streams of research, this thesis conducts a study of mathematical anxiety at the first year university level through a survey and data analysis, and proposes a theoretical model of learning. Throughout the data analysis, the prevalence, effects, and correlates of mathematical anxiety are examined. Using a version of the Mathematical Anxiety Rating Scale refined by Plake \& Parker in 1982, factors such as gender, high school performance, and program choices are shown to be correlated to mathematical anxiety, as is consistent with previous literature. On the other hand, the model of learning offers a theoretical perspective in understanding the relationship between knowledge, effort, and anxiety, and how these variables interact during a learning experience. This model suggests that given an individual's aptitude, drive, and susceptibility for anxiety, that they may reach various levels of knowledge, effort, and anxiety throughout an academic term. / Thesis / Master of Science (MSc)
39

Testing for Seropositivity of the Human Immunodeficiency Virus / Mathematical modelling of the AIDS pandemic

Boulanger, Cynthia Rose 12 1900 (has links)
This paper considers a series of models and the effect of HIV antibody testing on the dynamics of the disease. We examine HIV antibody testing in conjunction with persuasive techniques designed to encourage tested infected to behave in a sexually responsible manner. The population under consideration is a homosexual population. Analytical methods are used to obtain information about the qualitative behaviour of the models. Areas requiring further study are discussed. / Thesis / Master of Science (MSc)
40

METHODS FOR MODELING THE SPREAD OF INFECTIOUS DISEASE

Li, Michael January 2019 (has links)
Mathematical and statistical models are widely used in studying infectious disease. They provide important insights – including mechanisms of the spread of infectious disease, forecast epidemic size and duration, and effects of intervention strategies – which are useful in studying and combating infectious disease. Over the last couple of decades, modeling techniques have advanced tremendously due to improvements in computational power, data availability, and data accessibility; this enables researchers to use various modeling approaches to capture more realistic aspects of infectious disease epidemics. Despite having flexible modeling techniques, these approaches use different modeling assumptions to incorporate information and propagate uncertainty, often arriving at inconsistent conclusions. My work focuses on exploring and improving methods for modeling the spread of infectious disease; in particular, exploring the state of the art techniques for disease modeling in real epidemic outbreaks and simulation settings. Motivated by a synthetic forecasting challenge inspired by the 2014 West African Ebola outbreak, I compared simple Markov chain Monte Carlo approaches to simulated epidemics (Chapter 2). Using high-resolution data from an ongoing rabies contact- tracing study, I apply robust techniques to reassess global historical risk estimates of canine rabies (Chapter 3), and show that disease trait correlations bias generation time estimates, with implications for conclusions about control (Chapter 4). In Chapter 5, I developed a method to improve modeling trait relationships while incorporating phylogenetic relationships by reformulating phylogenetic mixed models to improve flexibility and speed. / Dissertation / Doctor of Philosophy (PhD)

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