Advanced Materials Research Vols. 121-122

Abstract: A novel approach to simulate soft tissue cutting in a virtual reality endoscopic simulator for surgical training is proposed in this paper. This approach is based on both the improved mass-spring model and the use of computational geometry. A virtual spring is introduced and harnessed to help compensate the shortcoming of the conventional mass-spring model, and a detection algorithm utilizing decomposition of affine coordinates is adopted for the purpose of determining the springs that intersect with the cutting plane. To speed up the simulation performance, algorithms and data structures for the cutting model are designed and implemented based on GPGPU (General-purpose computing on graphics processing units). The performance comparison on the GPU and CPU demonstrates that the proposed method is efficacious and practical.

Abstract: During the construction of a bridge, the construction procedures may change from the originally designed procedures due to some reasons like the weather. In this paper, the influence of construction procedures on the liner and stress is investigated for a prestressed continuous beam bridge with three spans. Finite element analysis indicated that construction procedures have great impact on the liner control and they affect the middle span and side span differently. Although different sets of construction procedures cause different stress at corresponding construction stages after the cantilever construction is finished, they have no significant influence on the stress of the finally built bridge. Test data agreed with finite element analysis. It is thus the influence of construction procedures on bridge liner control should not be neglected.

Abstract: The measurement and analysis system of nanoparticles size distribution was developed by using virtual instrument technology, while the photon counting technology was applied in the system to replace the expensive correlator. High speed photon pulse counter was designed. The real-time data of nanoparticles dynamic light scattering were analyzed in the mixed program of MATLAB and LabVIEW, where the time autocorrelation functions of nanoparticles light scattering signals of monodisperse and polydisperse are reversed by NNLS arithmetic. Experiments results show that the peak position, peak width and symmetry of inverse distribution are very close to the real simulate particles.

Abstract: By integrating network technology, virtual instrument technology, video image network transmission and web page fusion technology, the analysis system of ultrafine particles dynamic light scattering signals based on B/S mode was developed，Through internet explorer, the remote client can browse the real-time monitoring data, such as diameters of particles, the autocorrelation function curve, inversion results, power spectrum density, time-frequency distribution. The photon counting technology was applied in the system to replace the expensive correlator, the real-time data of ultrafine particles dynamic light scattering were analyzed by using Burg arithmetic of AR model, Much useful information of the particle size can be obtained by comparing the power spectrum of standard polystyrene particles scattered light signals of 450nm, 300nm, 200nm.

Abstract: Procedural texturing is a powerful way to add details to the surface of rendered objects. The Worley basis function of Cellular Texture is the most popular one and widely used to create various kinds of solid textures. However, most applications are implemented over 2D textures, which do not present varied illumination and viewpoint information. We present a method for creating surface height maps based on cellular textures and relighting them on 3D scenes. Furthermore, we implement our algorithm on GPU and show real-time relighting performance under arbitrary lighting directions.

Abstract: Curve fitting refers to the process of finding an appropriate function that fits a finite set of data points. Representing a set of data points by a function is quite beneficial in data analysis and reapplication, and this technique is often used in engineering and technical problems. Fitting accuracy and computational time are usually the most crucial factors to be taken care of in curve fitting problems. Previous researchers have demonstrated that genetic algorithms can effectively solve curve fitting problems, but the difficulty of parameter coding is also widely encountered in computational processes. Hence, this study addresses on applying real-valued genetic algorithm to deal with curve fitting problems. Detailed discussion is made on the optimization efficiency among various data, and finally, some key parameters to curve fitting results are found and presented.

Abstract: A new type of cathode gas sensor based on carbon nanotube film is presented to analyze CO and CH4 mixed gas. The structure and measuring principle of breakdown voltages are proposed to build support vector machine nonlinear model. As a result, the max relative error of CO and CH4 is 3.8% and 6.0%, respectively. This hints the sensor acts an accuracy measurement.

Abstract: Removed due to plagiarism

Abstract: As hierarchical storage is one of the highlights in researching and realizing of mass data storage, this paper mainly describes a study on data storage structure, evaluation of data importance and data management model of hierarchical storage.

Abstract: The Tridiagonal period Matrices, as an important tool, have much important applications ( such as in computational mathematics, physics, image processing and recognition, missile system design, nonlinear kinetics, economics and biology etc). In this paper, we give a fast algorithm for the inverse of the class of tridiagonal period matrices .