The use of Robin boundary conditions as interfacial transmission conditions in nonoverlapping domain decomposition iterative procedures was introduced by P.~L.~Lions and later discussed by a number of authors. In all of these discussions, the weighting of the flux and the trace of the solution were independent of the iterative step number. Recently, Douglas and Huang have considered an extension in which the weighting has depended on the iterative index and proved that an acceleration in the convergence rate similar to that occurring for alternating-direction iteration using a cycle of pseudo-time steps results. Combined methods have received a lot of attention on the study of the boundary value problems of elliptic equation with singularities domain. The objects of this paper are to extend this accelerated procedure to a singularity problem on a sectorial domain. We show that the convergence rate similar to that occurring for alternating-direction iteration results. Also, a combined method and the methodology of weighting parameter can be used to solve a singularity problem.

When we use the FDTD method to analyze electromagnetic problems, it has to properly discretize the space and time. Automeshing can non-uniformly discretize the simulated structure and generate gradual grids. To improve the efficiency of automeshing, we optimize the parameter of automeshing using the genetic algorithm. Without sacrificing accuracy, it searches a suitable ratio to reduce the generated grids and to save simulation time. At last, we optimize the PIFA using genetic algorithm and search automatically the height of the substrate and the feed position in order to obtain optimal performance. When we use the genetic algorithm, it is the key point to define an objective function evaluating the fitness of the optimized problem. It is important that the function has to appropriately describe the performance at that time.

In this work, based on both experimental and theoretical approach, the contact ESD behavior on a PCB circuit is investigated. The discharge mechanisms of ESD (Electrostatic Discharge) phenomena are discussed by both practical measurement and mathematic analysis. Simplified mathematic models include CR-R¡BCR-C and CR-L are proposed to explain the low frequency phenomena of ESD discharge events. Moreover, some experimental setups with good repeatability are demonstrated for measuring the ESD-induced noise on high-speed PCB and some countermeasures are suggested to reduce ESD damage.

A continuous formulation to calculate the dynamic stiffness matrix of structural members with distributed masses is presented in detail and verified with some simple examples. The dynamic model of a specific bridge (the Marga-Marga bridge in Chile) was developed using this formulation, and the model was then used to obtain the transfer functions of the motions at different points of the bridge due to seismic excitation. The model included rubber pads, used for base isolation, as additional members. The transfer functions were obtained with and without rubber pads to investigate their effect. The dynamic stiffness of complete pile foundations was calculated by a semi-analytical solution with Poulos?? assumption. General observations on group effects under various conditions were obtained from the result of these studies. The dynamic stiffness of the pile foundations for the Marga-Marga bridge was then obtained and used to study the soil structure interaction effects on the seismic response of the bridge. Records obtained during a real earthquake were examined and interpreted in light of the results from all these analyses. Finally, conclusions and recommendations on future studies are presented.

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Conventional gm-c filters have limited voltage swings in low voltage operation. CMOS companding filters replace gm-c filters in low voltage environment for high dynamic range. The square-root domain filter and log-domain filter belongs to this companding filter category. In this thesis, a second order low pass square root domain filter (SRD filter) based on the up-down TL (translinear loop) circuit structure is presented. The SRD filter consists of four geometric-mean cells and three squarer/divider cells. The advantages of the proposed circuits are low supply voltage, low power consumption, high bandwidth, and low total harmonic distortion (THD). The circuit has been fabricated with 0.35£gm CMOS technology. It operates with a supply voltage of 1.5V, and the bias current varies from 0.5£gA to 30£gA. Measurement results show that the cutoff frequency can be tuned from 3.12MHz to 8.11MHz when the Capacitance (C) is 5pF.The total harmonic distortion is 0.28%, and the power consumption is 1.09mW.

Workshop Mensch-Computer-Vernetzung Vergabe der IP-Adressen

Fachhochsch., Diplomarbeit.-07--Zugl.: Bielefeld, 2006. / Literaturverz. S. XIII - XVI.

Thesis (Ph. D.)--West Virginia University, 2000. / Title from document title page. Document formatted into pages; contains xiii, 325 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 138-144).

Zugl.: Düsseldorf, Univ., Diss., 2009