The objective of the proposed research is to design and develop a series of radio frequency identification (RFID) tag structures that exhibit good performance characteristics with cost optimization and can be realized on flexible substrates such as liquid crystal polymer (LCP), paper-based substrate and magnetic composite material for conformal applications. The demand for flexible RFID tags has recently increased tremendously due to the requirements of automatic identification in various areas. Several major challenges existing in today's RFID technologies need to be addressed before RFID can eventually march into everyone's daily life, such as how to design high performance tag antennas with effective impedance matching for passive RFID IC chips to optimize the power performance, how to fabricate ultra-low-cost RFID tags in order to facilitate mass production, how to integrate sensors with passive RFID tags for pervasive sensing applications, and how to realize battery-free active RFID tags in which changing battery is not longer needed. In this research, different RFID tag designs are realized on flexible substrates. The design techniques presented set the framework for answering these technical challenges for which, the focus will be on RFID tag structure design, characterization and optimization from the perspectives of both costs involved and technical constraints.

Granular materials are composed of solid, discrete particles and exhibit mechanical behavior that differs from those of fluids and solids. The rheology of granular flows is principal to a suite of natural hazards. Laboratory experiments and numerical models have adequately reproduced several features observed in terrestrial gravity driven geophysical flows; however, quantitative comparison to field observations exposes a failure to explain the high mobility and duration of many of these flows. The ability of a granular material to resist deformation is a function of the force chain network inherent to the material. This investigation addresses the evolutionary character of force chains in unconfined, two-dimensional, gravity driven granular flows. Our particular emphasis concerns the effects of stress localization on the substrate by dynamic force chain evolution and the implications for bed erosion in dense granular flows. Experimental systems employing photoelastic techniques provide an avenue for quantitative force analysis via image processing and provide dataset that can be used validate discrete element modeling approaches. We show that force chains cause extreme bed force localization throughout dynamic granular systems in spatial and temporal space; and that these localized forces can propagate extensively into the substrate, even ahead of the flow front.

No description available.

<p>In the present work studies were performed to provide understanding for further model development of the two-phase phenomena, film formation from o/w emulsions and slag foaming.</p><p>The drying of o/w emulsions of different oil viscosities on hydrophobic and hydrophilic substrates was studied. The hydrophobic substrate was found to destabilise the oil droplets and to result in a different mechanism for forming continuous oil film. Studies of adsorption behaviour of a series of non-ionic diblock copolymers at relevant interfaces showed that the adsorption behaviour at hydrophobic and hydrophilic solid surfaces differed at high polymer concentration. Emulsion droplets were found to interact with the hydrophobic interface. Adsorption at silicone oil-water interface resembled adsorption at solid hydrophobic surfaces.</p><p>Gas was generated through chemical reaction at the interface between two immiscible liquids and the bubbles formation from the generated was studied optically. The gas bubble size was seen to be uninfluenced by the reaction rate. However, bubble formation was seen to take place in one of the phases, held up at the interface before detaching from the interface with a surrounding aqueous film. It was argued that this may affect the final bubble sizes.</p><p>Slag foaming at high temperatures was studied in laboratory scale with X-ray imaging under dynamic conditions. The foam displayed a fluctuating behaviour, which the presently available models are not able to take into account. The concept of foaming index was found to be unsatisfactory in describing the foaming behaviour under dynamic conditions, thus emphasizing the need for alternative theories. The rate of fluctuations was seen to be related to the difference between rate of gas generation and rate of gas escape from the system (U_g-U_e) as well as the bubble sizes. Thus, it seems like model development of dynamic foaming phenomenon has to take the effective chemical reaction rate as well as the bubble sizes into consideration</p>

<p>In the era of VLSI the technological advancements have lead us to integrate not only digital circuits of high device density but both digital and analog circuits on to the same chip. In recent years the number of devices on a chip has spectacularly increased, all</p><p>because of the downward scaling in sizes of the devices. But because of this dramatic scaling the devices have become more sensitive to the power-ground noise. Now in designing a mix signal system within single silicon die that has high speed digital circuits</p><p>along with high performance analog circuits the digital switching noise becomes a foremost concern for the correct functioning of the system.</p><p>The purpose of the thesis is to evaluate the reduction of Simultaneous Switching Noise in analog signal band with in the chip. The experiment is done by the use of DCVSL circuits combined with a novel method of implementation, instead of the common static circuits in the core design. These DCVSL circuits have the property to draw periodic currents from the power supply. So if the circuit draws equal amount of current at each clock cycle independent of the input fed to it, the generated noise’s frequency content, produced due to current spikes will then be shifted above the input clock frequency.</p><p>The idea is to reduce Simultaneous Switching Noise (SSN) by half of the clock frequency in the frequency band. This frequency band often contains to the analog signal band of a digital-to-analog converter. To evaluate the method two pipelined adders have been implemented in 0.13 μm CMOS technology. The proposed method (test circuit) is</p><p>implemented using DCVSL techniques and the reference circuit using static CMOS logic. For testing of the design we generated the input data on-chip. The pseudo-random data is generated by implementing two different length PRBS. We have also implemented a ROM containing specific test patterns. In the end, we have achieved a 10 dB decrease of noise level at the substrate node on the chip.</p>

Title from PDF of title page. / Document formatted into pages; contains 71 pages. / Thesis (M.S.E.E.)--University of South Florida, 2003. / Includes bibliographical references. / Text (Electronic thesis) in PDF format. / ABSTRACT: This thesis concentrates on RF/microwave characterization and modeling of planar spiral inductors and pad stack parasitics. The inductors varied in size from 1.9 to 15.3 nH. Several approaches were examined for modeling the planar spiral inductors. The approach developed herein is built around an existing composite model (available in commercial computer-aided design software), with added series and shunt impedances at both the input and output of the existing composite model. Artificial neural network (ANN) software was used to determine the correction impedance values. Another approach investigated was to model the S-parameters of the inductor using a space- mapping model of the input parameters for the existing model. The correction impedance modeling approach was theoretically sound but the level of accuracy need for the ANN model was not obtainable. The space mapping approach had merit but a substrate and parameter scalable model could not be achieved. / ABSTRACT: A pad stack is a section of microstrip line that a surface mounted element is affixed to; these pad stacks are standardized for specific element sizes, so for example any 0805 (80 mils by 50 mils) element may have the same pad stack whether it is a capacitor, inductor or resistor. The pad stack models were necessary because a capacitor model originally developed at the University of South Florida did not include parasitic effects for different input connections. The pad stack parasitic models can be broken down into three types: dual-input, tri-input, and quad-input. Each of the dual- and tri- input models have input angles of either 0 degrees, 45 degrees, or 90 degrees. The models were developed using a combination of microstrip and lumped elements. / System requirements: World Wide Web browser and PDF reader. / Mode of access: World Wide Web.

Thesis (Ph. D.)--University of Washington, 2002. / Vita. Includes bibliographical references (leaves 189-202).

This dissertation presents the theory and practice of designing, synthesizing and using peptidomimetics to disrupt protein-protein interactions. Our general strategy is to design and synthesize peptidomimetics that will mimic peptide secondary structures (alpha-helices and beta-sheets). Chapter One is a theoretical examination of the feasibility of using beta-sheet mimics called molecular clamps to inhibit substrate-receptor interactions by blocking the substrate rather than the receptor or enzyme. Several natural and synthetic examples of this approach are given in support of this concept. We also present the results of a kinetic modeling study and a consideration of which types of systems would be the best candidates for a substrate-targeted inhibitor approach. Chapter Two relates a continuation of previous work in our lab to synthesize five novel beta-protected hydrazino amino acids. These hydrazines are essential precursors for synthesizing constrained beta-strand mimetics. We showed that we could selectively deprotect the alpha-nitrogen of the hydrazines, and we synthesized several novel examples of polar beta-protected hydrazino amino acids. Chapter Three discusses the design and synthesis of small-molecule and peptidomimetic MDM2 inhibitors, including our work on synthesizing a new class of alpha-helix mimics that have improved water solubility compared with previously reported examples of alpha-helix mimics. As with the constrained beta-strand mimics described in Chapter Two, the synthesis of novel hydrazino amino acid precursors is a key step in synthesizing our alpha-helix mimics. One isoleucine hydrazine derivative was synthesized, and progress was made toward synthesizing two other hydrazines from tryptophan. In addition, the synthesis of three potential small-molecule inhibitors of MDM2 is described. Chapter Four describes the use of the GLIDE program to design and evolve an alpha-helix mimic that will interact with the pro-apoptotic protein Bax. Progress toward the synthesis of this compound is also reported.

Malaria remains a serious concern for people living and traveling to warm climates in Africa, Asia, and some parts of America. Understanding the mechanism of the malaria parasite in the liver phase could lead to important discoveries for preventative and treatment therapeutics before the disease develops into the blood stage. While in vitro liver cell culture models have been explored, a device that mimics the liver cell architecture with the capability of high-resolution imaging has never been created. In this research, a cell culture microfluidic device was designed and fabricated with a membrane integrated design to mimic the architecture of a liver, cell chamber dimensions affable for high-resolution imaging, and fluidic port design for optical access to both sides of the membrane for the study of malaria parasite invasion.

Indentation is used as a technique for mechanical characterization of materials for a long time. In the last few decades, new techniques of mechanical characterization at micro and nano level using indentation have been developed. Mechanical character-ization of thin films has become an important area of research because of their crucial role in modern technological applications. Theoretical and computational models of indentation are less time consuming,cost effective, and flexible. Many researchers have investigated mechanical properties of thin films using theoretical and computational models. In this study, an indentation model for a thin layer-substrate geometry with the possibility of nonhomogeneous or homogeneous interface of finite thickness between layer and substrate has been developed. The layer and substrate can be nonhomogeneous or homogeneous. Three types of indenters are modeled: 1) Uniform pressure indenter 2) Flat indenter 3) Smooth indenter. Contact depth, maximum interfacial normal stress and maximum interfacial shear stress play an important role in design and mechanical characterization of thin films using indentation and the effect of modeling the interface as homogeneous and nonhomogeneous on these parameters is studied. A sensitivity analysis is also conducted to find the effect of indentation area, substrate to layer Young's modulus ratio, layer to interface thickness ratio on contact depth and critical interfacial stresses.