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Developing A Gis And Hydrological Modeling Approach For Sustainable Water Resources Management In The West Bank -- Palestine, Walid Wajeeh Sabbah
Developing A Gis And Hydrological Modeling Approach For Sustainable Water Resources Management In The West Bank -- Palestine, Walid Wajeeh Sabbah
Theses and Dissertations
This research deals with setting up a GIS and hydrological modeling based approach for sustainable water resources management in the West Bank of Palestine. This water sustainability approach took into consideration the water balance, the social, the economic, the demographic, the environmental, and the institutional components in order to enhance and promote the sustainable development in Palestine, both on the short and long runs. To evaluate the water balance component, a methodology was introduced to create the Water Sustainability Map (WSM). Since the groundwater is currently the only accessible water source by the Palestinians, the WSM is represented by the …
Modeling And Slew-Maneuver Control Of A Flexible Spacecraft, Jeremy E. Eckhart
Modeling And Slew-Maneuver Control Of A Flexible Spacecraft, Jeremy E. Eckhart
Master's Theses - Daytona Beach
Slew-maneuver control problem is studied for a flexible spacecraft consisting of a rigid main body to which a long flexible appendage is attached. Nonlinear dynamical system models are developed using both distributed parameter modeling and discrete parameter modeling; these models are shown to be equivalent for appropriately chosen system parameters. Lyapunov-based nonlinear feedback controllers are designed for the control of rigid-body motion while suppressing the lowest frequency vibrational mode. In case of large-angle maneuvers, these nonlinear controllers are shown to outperform the linearization-based controllers including the filtered proportional-derivative (PD) controllers as well as the linear quadratic regulator (LQR) controllers. Finally, …
Electrothermomechanical Modeling Of A Surface-Micromachined Linear Displacement Microactuator, Christian D. Lott
Electrothermomechanical Modeling Of A Surface-Micromachined Linear Displacement Microactuator, Christian D. Lott
Theses and Dissertations
The electrothermomechanical characteristics of an electrically-heated polycrystallinesilicon microactuator are explored. Using finite-difference techniques, an electrothermal model based on the balance of heat dissipation and heat losses is developed. For accurate simulation, the relevant temperature dependent properties from the microactuator material are included in the model. The electrothermal model accurately predicts the steady-state power required to hold position, and the energy consumed during the thermal transient. Thermomechanical models use the predictions of temperature from the electrothermal solution to calculate displacement and force from pseudo-rigid-body approximations and commercial finite-element code. The models are verified by comparing experimental data to simulation results of …
A New Paradigm Of Modeling Watershed Water Quality, Fan Zhang
A New Paradigm Of Modeling Watershed Water Quality, Fan Zhang
Electronic Theses and Dissertations
Accurate models to reliably predict sediment and chemical transport in watershed water systems enhance the ability of environmental scientists, engineers and decision makers to analyze the impact of contamination problems and to evaluate the efficacy of alternative remediation techniques and management strategies prior to incurring expense in the field. This dissertation presents the conceptual and mathematical development of a general numerical model simulating (1) sediment and reactive chemical transport in river/stream networks of watershed systems; (2) sediment and reactive chemical transport in overland shallow water of watershed systems; and (3) reactive chemical transport in three-dimensional subsurface systems. Through the decomposition …
Modeling And Simulation Of Long Term Degradation And Lifetime Of Deep-Submicron Mos Device And Circuit, Zhi Cui
Electronic Theses and Dissertations
Long-term hot-carrier induced degradation of MOS devices has become more severe as the device size continues to scale down to submicron range. In our work, a simple yet effective method has been developed to provide the degradation laws with a better predictability. The method can be easily augmented into any of the existing degradation laws without requiring additional algorithm. With more accurate extrapolation method, we present a direct and accurate approach to modeling empirically the 0.18-ìm MOS reliability, which can predict the MOS lifetime as a function of drain voltage and channel length. With the further study on physical mechanism …
The Development Of A Fuzzy Model To Quantify Training Andeducational Factors And The Resulting Impact On Student Successand Lear, Chandre Butler
The Development Of A Fuzzy Model To Quantify Training Andeducational Factors And The Resulting Impact On Student Successand Lear, Chandre Butler
Electronic Theses and Dissertations
The utilization of fuzzy mathematical modeling for quantification of the quality of training and educational delivery is an innovative application that can result in measurable and repeatable results. This research was designed to apply proven quantification techniques and Industrial Engineering methodologies to a nontraditional environment. The outcomes of this research provide the foundation, initial steps and preliminary validation for the development of a systematic fuzzy theoretical model to be applied for the quantification of various areas within training and education delivery. The test bed for this methodology is Orange County Public School system, the twelfth largest school district in the …
An Automated Methodology For A Comprehensive Definition Of The Supply Chain Using Generic Ontological Components, Mohamed Fayez
An Automated Methodology For A Comprehensive Definition Of The Supply Chain Using Generic Ontological Components, Mohamed Fayez
Electronic Theses and Dissertations
Today, worldwide business communities are in the era of the Supply Chains. A Supply Chain is a collection of several independent enterprises that partner together to achieve specific goals. These enterprises may plan, source, produce, deliver, or transport materials to satisfy an immediate or projected market demand, and may provide the after sales support, warranty services, and returns. Each enterprise in the Supply Chain has roles and elements. The roles include supplier, customer, or carrier and the elements include functional units, processes, information, information resources, materials, objects, decisions, practices, and performance measures. Each enterprise, individually, manages these elements in addition …
Modeling The Fate And Transport Of Chlorinated Benzenes In Baton Rouge Bayou, Sudheer Nimmagadda
Modeling The Fate And Transport Of Chlorinated Benzenes In Baton Rouge Bayou, Sudheer Nimmagadda
LSU Master's Theses
Knowledge of the fate and transport of chlorinated benzenes is necessary at certain sites for effective remediation of contaminated soils using plants. Current research is examining the capability of wetland plants to catalyze degradation or attenuate migration, but again requires knowledge of the uptake of contaminants from an aqueous environment. A two stage model was used to estimate the rate of uptake of contaminants from sediments. The first stage of the model predicts pollutant leaching rates from sediments to the overlying water, which would then be fed into the plant or bioreactor model systems. In this study the flux from …
Numerical Modeling Of Synthetic Jets In Quiescent Air With Moving Boundary Conditions, Nicholas D. Castro
Numerical Modeling Of Synthetic Jets In Quiescent Air With Moving Boundary Conditions, Nicholas D. Castro
Theses and Dissertations
Flow control is a key factor in optimizing the performance of any vehicle moving through fluids. Particularly, in aerodynamics there are many potential benefits for implementing synthetic jets to achieve aircraft designs with less moving parts, uper- maneuverability, and separation control for fuel economy. Piezoelectric synthetic jets are of special interest because of their lightweight and low power consumption. Numerous publications on such jets are available. Actuator properties and boundary conditions relevant to this particular application however are often overlooked. The focus of this project is to numerically model synthetic jets in quiescent air to study the influence of cavity …
Analysis And Shape Modeling Of Thin Piezoelectric Actuators, Makram Mouhli
Analysis And Shape Modeling Of Thin Piezoelectric Actuators, Makram Mouhli
Theses and Dissertations
The field of smart materials is an increasingly growing area of research. In aerodynamics applications especially, transducers have to fulfill a series of requirements such as light weight, size, energy consumption, robustness and durability. Piezoelectric transducers, devices which transform an electrical signal into motion, fulfill many of these requirements. Specifically, piezoelectric composites are of interest due to their added toughness and ease of integration into a structure. Resulting composites have a characteristic initial curvature with accompanying residual stresses that are responsible for enhanced performance, relative to flat actuators, when the active material is energized. A number of transducer designs based …