A computer modelling method for the three-dimensionaldynamic analysis of liquid crystal display cells is presented. Themethod is based on a variational approach to the Oseen-Frank freeenergy formulation considering three elastic constants and uses avectorial representation of the director field. A simpler approximateform that uses only two elastic constants but is faster to operate isobtained as a by-product of the full three-constant modelimplementation. The modelling uses finite elements on a mesh oftetrahedral elements for the calculation of directors and electricpotentials while finite differences in time are used in the time steppingprocess. Comparisons are made with results from a 2D dynamicprogram using a tensor model giving good agreement.

The influence of solute atoms on point-defect properties and defect generation by radiation damage in alloys is known to be important, and hence it is desirable to understand their effect on the basic mecha- nisms involved. Most computer modeling of these phenomena has only considered pure metals, but as part of a project to investigate displacement cascades in alloys, we have simulated dilute solutions of gold (Au) in copper (Cu), treating this as a "model" for a heavy, oversized solute alloy system. In the present paper, modified many-body interatomic potentials for the Cu-Au system are described that are suitable for modeling high-energy atomic collisions. The properties of point defects in pure copper and the dilute alloy, including solute-defect binding energies, are presented. The oversized solute has a larger binding energy with an interstitial atom than with a vacancy. The displacement threshold energy, Ea, of a Cu atom and a Au atom in the copper matrix has been investigated as a function of primary recoil direction, and the difference between the two species is found to be substantial. Furthermore, the pres- ence of a Au solute has a significant effect on the formation of Frenkel pairs by the replacement- collision-sequence mechanism. These results are discussed in terms of the mass and size difference of Cu and Au atoms.

By a thorough analysis of the contents and scope of the publiclogistics information, a role-based multilevel solution of information sharing isproposed. And by use of metadata theory, the unified description andclassification of the information are done with an aim to achieve heterogeneousdata sharing and exchanging. Based on this, a service-oriented-architecture(SOA)-based system framework is put forward in order to integrate and reuseexisting systems, data and service resources. By introducing web service andbusiness process execution language (BPEL), etc. into the solution, servicesreuse and businesses automatisation are achieved. In this way, the degree ofinformatisation of supply chains management can be deepened, the interactionsbetween governmental departments and enterprises can be enhanced and theprocess of customs e-governing can be accelerated. Finally, an application ofthe solution to a logistics customs clearance information sharing platform isalso given to show its applicability.

3D human motion analysis system is gaining more and more popularity and importance in sports training, game simulation and many other areas. Particle filter algorithm, as a powerful optimized method, can be applied to 3D human motion analysis system with more accurate results delivered and assured. An improved (hybrid) particle filter algorithm (IPFA) is proposed in this paper which integrates the advantages of partitioned particle filter algorithm (PPFA) with annealed particle filter algorithm (APFA). The results show that, the hybrid algorithm (IPFA) gives rise to more accurate results with less computational time consumed, compared to PPFA and APFA, and improves tracking efficiency and accuracy of 3D human motion substantially.

We present a new formulation for the dynamicmodeling of twisted nematic liquid crystal display cells based on aconstant charge assumption instead of the commonly used "fixedvoltage" model. This formulation is based on a tensor representationof the director field, which is solved using a combination offinite-element and finite-difference methods. It allows the accuratemodeling of liquid crystal pixel cells in thin-film-transistor-drivenactive matrix displays, extensively used in flat panel computer andtelevision displays.