It is well known that the finite difference time domain (FDTD) method is a powerful numerical analysis tool for solving electromagnetic problems. In a simulated area, in order to discretize an object which is much smaller than the others, a very small space increment is needed and hence the time step should be decreased too for stability consideration in traditional FDTD. The small space and time increments will respectively increase the memory requirement and calculation time. To overcome these problems, some numerical methods were developed, such as the subcell and nonuniform grid method, to handle the small feature size. This thesis describes an efficient method for generating FDTD subcell equations. We construct a second order macromodel system instead of the subcell region in conventional FDTD. The macromodel system can be reduced with model order reduction techniques (MOR) and then translated into new FDTD update equations. When the problem contains several objects of the same size and material properties, the MOR subcell has the advantage of reusability. This means that the reduce-order model of the object needs to be generated only once nonetheless can be applied to every position where the objects originally occupied.

¡@In this thesis, a novel subgridding scheme is proposed based on the hybridization of the FDTD and CNDG-FDTD algorithms. The FDTD method is applied to the coarse grid region, while the CNDG-FDTD method is used in the fine grid region. Because of the unconditional stability of the CNDG scheme, the temporal step size can be set equal to that in the coarse grid region to speed up the computation in the fine grid region. Furthermore, the temporal interpolation at the fine and coarse grids interface is no longer necessary and thus the complexity of spatial interpolation is largely reduced. ¡@As the CNDG-FDTD method is free from the CFL condition restraint, it saves a large amount of CPU time. Numerical results agree very well with that of the FDTD scheme. But it requires a larger amount of computer memory, at least 20% more than the FDTD method. A modified version of the CNDG-FDTD scheme with increased memory efficiency is also presented. It has not only eliminated the restraint of the CFL condition, but also achieved a more efficient saving of CPU time and computer memory requirements.

A mathematical model considering ellipsoidal surface for the forming tube is proposed in this work to examine the plastic deformation behavior of a thin-walled tube during tube bulge hydroforming process in an open die. In the formulation of this mathematical model, nonuniform thinning in the free bulged region and sticking and sliding friction modes between the tube and die are considered. In the sticking friction mode, the elements in contact with the die do not move or slide after contact with the die. Whereas, in the sliding friction mode, the elements in contact with the die will continue to deform plastically in the subsequent forming process. The relationship between the internal pressure and the bulge height of the tube is examined. The effects of various forming parameters such as the die entry radius, the initial thickness, the length/diameter ratio, material property, etc., upon the forming pressure and the thickness distribution of products were discussed systematically.

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.

In part I, a numerical study of the mixed states in a mesoscopic type-II superconducting cylinder is described. Steady-state configurations and transient behavior of the magnetic vortices for various values of the applied magnetic field H are presented. Transitions between different multi-vortex states as H is changed is demonstrated by abrupt changes in vortex configurations and jumps in the B vs H plot. An efficient scheme to determine the equilibrium vortex configuration in a mesoscopic system at any given applied field, not limited to the symmetry of the system, is devised and demonstrated. In part II, a superconducting thin film is subject to a non-uniform magnetic field from a vertical magnetic dipole, consisting of two magnetic monopoles of opposite charges. For a film with constant thickness and with no pins, it has been found that the film carries two pairs of vortex-antivortex in the steady state in the imposed flux range of 2.15 < (Phi)+ < 2.90 (in units of flux quantum) and no vortex at all for (Phi)+ <= 2.15. Transitions from a superconducting state with 3 pairs of vortex-antivortex to one with 2 pairs, where a pair of vortex-antivortex annihilates, have been observed in the pseudo-time sequence. With a perturbation with antidots (holes), vortexantivortex pair has been created for lower magnetic fluxes down to (Phi)+ = 1.3. In the sample of size 16(Xi) x 16(Xi), the attraction force between the vortex and antivortex always dominates over the pinning force, so that they eventually come out of pins, move toward each other, and annihilate each other. The annihilation rate, measured with time taken for the annihilation, is reduced noticeably by the increase of the distance between pins, or the increase in the pin size. A simulation of the magnetic vortex pinning in the sample of size 32(Xi) x 32(Xi) suggests we are likely to achieve pinning of the vortex-antivortex pair with the sample size around this and vortex-antivortex separation of 22(Xi). Using this sample as a template, the maximum density of pinned vortices achievable is calculates to be about 7.6 x 10^14 vortices/m2 for (Xi) =~ 1.6A°.

The common idea of love is a fusion of the individuals into one. The idea has permeated throughout society so that it has now been taken for granted. Such an idea of fusion of two individuals is actually harmful rather than helpful. In this thesis, I will show why the fusion model is not a prime model of love that one should follow, starting with Sartre. He is the paradigmatic example of the traditional model of love going wrong. By taking the fusion model to its final culmination, love is impossible or among other things sadomasochistic. Beauvoir reads Sartre's view as a bad-faith version of love. She inserts her view by giving an account of the €œwoman in love which is an example of a woman under Sartre'€™s interpretation of love. After showing why love under Sartre cannot be true, Beauvoir states that authentic love can only happen if the individuals are equal. That way, love can have grounds for culmination and fusion. Irigaray looks at the fusion model as debunked. She sees what Sartre and Beauvoir try to do but they are still assuming major things. Irigaray states that genuine love is based on the differences particularly sexual differences €”which Sartre and Beauvoir have failed to realize. By looking at Irigaray'€™s account of love, the traditional fusion model is debunked and love based on differences is applauded.

none

¡@¡@Lewis Carroll in his Alice¡¦s Adventures in Wonderland and Through the Looking Glass creates in two journeys of dreams a singular space-time, in which the non-sense words, paradoxical conversations, anti-causality events, disordered time and labyrinthine space are permeated. It is, beyond doubt, a space-time of Virtual. Thus, Virtuality is the point of the thesis, and the Dream is the initial of Virtuality. The author attempts to reflect the thinking-gesture that Carroll ever develops in terms of Writing(form) and Dream (content). ¡@¡@First, Alice¡¦s story as a virtual text, demonstrates the Dream by the special language¡Xin particular Carroll¡¦s answerless riddles, the portmanteau words with meaning-implosion, and the homophones which show the displacement of sense¡Xto attack the representation of thought, allowing us to see the impotence of designation in language. Dream, functioning as the absolute difference of actuality, will not possibly be the sameness of actuality. The dream is thus not the permutation of the experience of actuality, even though they may be similar or mirrors of each other. However, this is not a representation of actuality, but a demonstration of repetition. If not, it will be mere actual, not virtual. For Carroll, Dream is a virtual field that coexists with actuality, and both virtuality and actuality should be regarded as absolute Difference, with respective reality. ¡@¡@Moreover, Alice¡¦s adventure, with its un-sequential events¡Xas the plot ¡§murdered time¡¨ in story suggests¡Xcreates a time without its chronological flowing, but a time suspended. The time is on the one hand a moment that suspensive, and is a most intensive instant on the other hand, where all the forces encounter, resonate and emit at this ultimate second. Thus, the Dream becomes a purely intensive world, and Alice is the continuum of intensities which constitutes by dynamically linked events. Plus, through the differentiating and repetition of the Dream, Alice¡¦s Adventures in Wonderland and Through the Looking Glass folds another book with the same title, a Double of eternal absent in actuality¡Xthe shine of virtual names by Lewis Carroll thus emerges.

In the present study, a two-dimensional numerical model based on a time-independent finite difference method was developed and the model is used to analysis the dynamic interaction among wave, sloshing fluid in tank and the floating tank. The free surface of wave and sloshing fluid in the tank are all assumed to be a single value function and the wave breaking is, therefore, not considered in the study. The numerical model is firstly validated by some bench make studies. Extensive simulation were made to discuss the effects of geometry of the floating tank, the ratio of depth to breadth of fluid in tank, the fundamental freq of floating tank ¡V structure system etc.