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Physically based simulation of human hair is a well studied and well known problem. But the “pure” physically based representation of hair (and other animation elements) is not the only concern of the animators, who want to “control” the creation and animation phases of the content. This paper describes a sketch-based tool, with which a user can both create hair models with different styling parameters and produce animations of these created hair models using physically and key frame-based techniques. The model creation and animation production tasks are all performed with direct manipulation techniques in real-time.  相似文献   
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A parametric study of linearly tapered slot antenna (LTSA) in air and a method for optimization of its pattern are presented. A method of moments code is utilized to investigate the behavior of LTSA’s as the length, height and the taper angle varies. It is shown that the antenna pattern can be improved using a top layer of dielectric material with varying permittivity.  相似文献   
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安南  张申生  胡涛 《计算机工程》2003,29(6):17-18,26
介绍了Cit-CSP--Cit/E-commerce信息安全保障平台子系统,并阐述了它所提供的消息摘要、块加密、加密(公钥)、签名和MAC等功能和服务。  相似文献   
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本文研究了无线局域网中使信号频谱得到优化的一种简单OFDM子载波加载算法。此算法基于边缘自适应(Margin Adaptive)加载准则及其在室内无线信道上的性能。  相似文献   
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In this work we present the discrete models for dynamic fracture of structures built of brittle materials. The models construction is based on Voronoi cell representation of the heterogeneous structure, with the beam lattice network used to model the cohesive and compressive forces between the neighboring cells. Each lattice component is a geometrically exact shear deformable beam which can describe large rigid body motion and the most salient fracture mechanisms. The latter can be represented through the corresponding form of the beam constitutive equations, which are derived either at microscale with random distribution of material properties or at a mesoscale with average deterministic values. The proposed models are also placed within the framework of dynamics, where special attention is paid to constructing the lattice network mass matrix as well as the corresponding time-stepping schemes. Numerical simulations of compression and bending tests is given to illustrate the models performance.  相似文献   
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The early twentieth-century invention of the airplane brought on a cultural euphoria that influenced the works and writings of urbanists, architects, artists, and science-fiction writers during the 1920s and 1930s. Le Corbusier's urban design for Rio de Janeiro—which he sketched, so he claimed, from an airplane—offers a visual basis to study how the aesthetic experience of flight was translated spatially, visually, and politically into his design of the future city. The polemics informing Le Corbusier's aerial "discovery" of South American geography revealed that there was a new empowerment in the act of looking from above, and that the spatial characteristics of his subsequent design interventions evoked that empowerment.  相似文献   
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A consistent formulation of the geometrically linear shell theory with drilling rotations is obtained by the consistent linearization of the geometrically non-linear shell theory considered in Parts I and II of this work. It was also shown that the same formulation can be recovered by linearizing the governing variational principle for the three-dimensional geometrically non-linear continuum with independent rotation field. In the finite element implementation of the presented shell theory, relying on the modified method of incompatible modes, we were able to construct a four-node shell element which delivers a very high-level performance. In order to simplify finite element implementation, a shallow reference configuration is assumed over each shell finite element. This approach does not impair the element performance for the present four-node element. The results obtained herein match those obtained with the state-of-the-art implementations based on the classical shell theory, over the complete set of standard benchmark problems.  相似文献   
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