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101.
三层土壤中垂直棒接地电阻的解析计算方法 总被引:1,自引:1,他引:1
基于等值土壤电阻率的概念,导出了三层土壤中垂直棒接地电阻解析计算公式。验证计算结果表明:解析公式与计算机数值计算法结果相比较,计算误差小,具有实用价值。 相似文献
102.
103.
Robust and Rapid Generation of Animated Faces from Video Images: A Model-Based Modeling Approach 总被引:1,自引:0,他引:1
Zhengyou Zhang Zicheng Liu Dennis Adler Michael F. Cohen Erik Hanson Ying Shan 《International Journal of Computer Vision》2004,58(2):93-119
We have developed an easy-to-use and cost-effective system to construct textured 3D animated face models from videos with minimal user interaction. This is a particularly challenging task for faces due to a lack of prominent textures. We develop a robust system by following a model-based approach: we make full use of generic knowledge of faces in head motion determination, head tracking, model fitting, and multiple-view bundle adjustment. Our system first takes, with an ordinary video camera, images of a face of a person sitting in front of the camera turning their head from one side to the other. After five manual clicks on two images to indicate the position of the eye corners, nose tip and mouth corners, the system automatically generates a realistic looking 3D human head model that can be animated immediately (different poses, facial expressions and talking). A user, with a PC and a video camera, can use our system to generate his/her face model in a few minutes. The face model can then be imported in his/her favorite game, and the user sees themselves and their friends take part in the game they are playing. We have demonstrated the system on a laptop computer live at many events, and constructed face models for hundreds of people. It works robustly under various environment settings. 相似文献
104.
The process of penetrating into granite was simulated by using program LS-DYNA3D. The granite was represented by the isotropic elastic-plastic model with failure criterion and the projectile was modeled by rigid model. The depth of penetration from simulations is identical with experiments. Penetration deceleration vs striking velocity was acquired at the same time, which can assist in the design of penetration weapons with payload and fuse. Through numerical simulation, that material model is considered with straightforward physical meaning, a few parameters which can be determined easily are more practical for engineering calculation along with experiments. 相似文献
105.
ZHUYing-dan WANGJi-hui TANHua GAOGuo-qiang 《武汉理工大学学报(材料科学英文版)》2004,19(2):94-97
The present work considered the capillary micro-flow through a fiber bundle. The resin heights in the fiber btundle as a function of time were used to detemine the experimental valises of capillary pressure and the permeability by the nonlinear regression,fitting method. The fitting curves showed a good agreement with experiments. However, these values of capillary pressure from short-time experiments were much lower than the theoretical results from the Yang-Laplace Equation. More accurate capillary presswre was predicted from the presented long-run experiment. 相似文献
106.
以钢种为Q235,直径为φ14的圆钢精轧最后三道为研究对象,采用Gleeble 1500D热模拟实验机研究并分析了不同变形工艺和冷速对实验钢组织的影响,同时针对实验结果,提出了一种晶粒细化的工艺制度. 相似文献
107.
108.
朱红斌 《冶金标准化与质量》2004,42(1):5-8
综述了ISO TC17 SC17秘书处制定的最新盘条和钢丝国际标准的内容和特点 ,提出我国盘条和钢丝国家标准与国际标准接轨的“双向原则”及具体实施方法。 相似文献
109.
介绍唐钢大盘重碳素焊条钢热轧盘条的研制及生产情况。针对该钢种化学成分及力学性能进行了统计、回归分析 ,并对化学成分进行优化 相似文献
110.
The effect of rare earth element Ce on microstructure, electrical conductivity and mechanical properties was studied.Using optical microscope, scanning electron microscope, transmission electron microscope and X-ray diffractometer, the microstructure and phase composition of aluminum rod for electrical purpose were measured and analyzed.The results indicate that rare earth element Ce can considerably refine grain size of aluminum rod for electrical purpose,improve the regular distribution pattern of the impurity, such as silicon and iron which present in the aluminum matrix,form stable metal compound with pernicious impurity.This metal compound precipitates on the crystal boundary.As a result, the solid solubility of impurity in aluminum reduce, and the electrical conductivity of aluminum rod for electrical purpose is improved.It is found that the mechanical properties of aluminum rod for electrical purpose are improved by rare earth element in certain range of RE addition. 相似文献