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In order to observe the physical values (magnetic flux density and eddy current) in 3D magnetic field analysis, an interactive and highly manipulative visualization system depicting stereo images is intalled in a graphics workstation with high functional graphic processors. The system has the following characteristics:
  • 1 An interactive and highly manipulative menu window with many functions: it enables visualization of complex phenomena in a 3D field through observation of various combinations of physical values from various viewpoints.
  • 2 Simultaneous display of both magnetic flux density and eddy current by using the appropriate use of two colour display methods for stream lines and distribution maps of density: this function facilitates observation of the mutual relations between two physical values in a 3D field.
  • 3 Animations and stereo displays: since they give extremely distinct images, observers can easily understand even highly complex 3D phenomena.
In this paper, the calculation method of density vectors, their display methods, and interactive functions are described. Some examples are also illustrated.  相似文献   
3.
A method is proposed for compositing 3-D images produced by different programs, taking depth order into consideration. The method can add the following effects to composited images: antialiased images with scaling are displayed by a simple algorithm; the algorithm can add shading effects due to various types of light, such as area sources and skylight; and ray tracing can be performed in localized regions, producing realistic results without the computational expense of ray tracing the whole image. In addition to the above processes, such shading effects as fog and texture mapping can be processed with conventional methods. Thus, it becomes possible to display complex scenes with various shading effects, using relatively small computers. The multiscanning method used for antialiasing and a data structure for processing it are described. Examples are presented to demonstrate the capability of the system  相似文献   
4.
The display of natural scenes such as mountains, trees, the earth as viewed from space, the sea, and waves have been attempted. Here a method to realistically display snow is proposed. In order to achieve this, two important elements have to be considered, namely the shape and shading model of snow, based on the physical phenomenon. In this paper, a method for displaying snow fallen onto objects, including curved surfaces and snow scattered by objects, such as skis, is proposed. Snow should be treated as particles with a density distribution since it consists of water particles, ice particles, and air molecules. In order to express the material property of snow, the phase functions of the particles must be taken into account, and it is well-known that the color of snow is white because of the multiple scattering of light. This paper describes a calculation method for light scattering due to snow particles taking into account both multiple scattering and sky light, and the modeling of snow.  相似文献   
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Adhesive and surface-chemical properties of poly(styrene macromer-butyl acrylate) copolymers, poly (styrene-butyl acrylate macromer) copolymers and poly (styrene-butyl acrylate) random copolymers were investigated. The results were as follows:

(1) The adhesive properties of the copolymers which were prepared by the macromer-technique were different from the random copolymers.

(2) It was found that there were differences in the surface and molecular structure between the copotymers which were prepared by the macromer technique and the random copolymers. These differences were evident from the results of measurements of the surface free energy of the copolymers and of the interfacial tension of water/toluene in the presence of the copolymers.

(3) The reason why there were differences in the surface and molecular structure seemed to be that the copolymers which were prepared by the macromer technique had graft chains and a different inner-structure from the random copolymers. Therefore, it was suggested that the graft copolymers which were prepared by the macromer technique had a phase-separated structure.  相似文献   
7.
Emulsifier-free emulsion polymerization of styrene in acetone–water medium was carried out using potassium persulfate as initiator. Below acetone content of 40 vol %, stable emulsion was prepared and polymerizations were remarkably fast compared with those in pure water. The particle size decreased from 0.5 to 0.17 μm with an increase in acetone content in the range 0–40 vol %, and the distributions were very sharp. The optimum polymerization for the preparation of the stable emulsion was: styrene, 20 vol %; acetone/water, 40/60 (v/v); KPS, 3.4 × 10?3 mole/l; temp., 90°C.  相似文献   
8.
Urease-immobilized ethylene-vinyl alcohol copolymer (EVA) membrane was prepared by the covalent bonding of urease on EVA membrane activated with cyanuric chloride. The urease-immobilized EVA membrane had optimum pH at about 7.0 similar to native urease. The Michaelis constant (Km) and the maximum velocity (Vm) of the urease-immobilized EVA membrane were smaller than those of native urease. When the EVA membrane, prepared on a polyethylene (PE) plate by the phase inversion method, was used as a support, urease was asymmetrically distributed in the direction of cross section of the urease-immobilized EVA membrane. The permeation decomposition of urea through the asymmetrically urease-immobilized EVA membrane depended on the asymmetric distribution of urease in the membrane. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 63: 1579–1588, 1997  相似文献   
9.
The vinyltrimethoxysilane‐grafted ethylene‐propylene copolymer/trifunctional methoxysilane (EPR‐g‐VTMS/RTMS) composites were prepared via in situ silica sol–gel reactions. Five trifunctional methoxysilane compounds (n‐hexyltrimethoxysilane, n‐decyltrimethoxysilane, n‐tetradecyltrimethoxysilane, n‐octadecyltrimethoxysilane, and phenyltrimethoxysilane) have been selected for this study. The water‐cross‐linked EPR‐g‐VTMS/RTMS composites were characterized by attenuated total reflectance‐Fourier transform infrared spectroscopy, gel content, solid‐state 29Si CP/MAS NMR, wide‐angle x‐ray scattering, tensile strength, and field emission scanning electron microscopy measurements. The type of RTMS additive has a substantial influence on the nature of siloxane band networks and eventually the mechanical tensile properties. This finding suggests that the interaction and/or entanglement between the EPR‐g‐VTMS matrix and the substituent of the RTMS additives are crucial for the modifying mechanical properties. Moreover, for the water‐cross‐linked EPR‐g‐VTMS/CnTMS (n = 6, 10, 14, and 18) composites, the joint evidence provided by attenuated total reflectance‐Fourier transform infrared spectroscopy, 29Si CP/MAS NMR, and wide‐angle x‐ray scattering results suggested the formation of ladder‐type poly(n‐alkyl silsesquioxane)s and the presence of the highly ordered structure with a thickness equal to the length of two n‐alkyl groups in all‐trans conformation. POLYM. ENG. SCI., 2011. © 2010 Society of Plastics Engineers.  相似文献   
10.
A unidirectional continuous-carbon-fibre-reinforced composite was subjected to stress in the direction perpendicular to the fibre direction. By X-ray diffraction, the stress on the incorporated fibre in the composite under transverse load was monitored, and the effects of the environment (water, heat) on stress transfer in the composite were investigated. The adhesion between the matrix and the fibre was irreversibly destroyed by the water absorption and/or cyclic heating, which is found to bring worse stress transfer to the incorporated fibre. X-ray diffraction is a powerful tool for monitoring the stress transfer and its environmental deterioration behaviour in the composite in situ and non-destructively.  相似文献   
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