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51.
52.
我国矿用牙轮钻头同世界先进水平相比有较大差距,大力开展矿用牙轮钻头CAD/CAM/CAE工作,促进学科交叉融合,是摆脱落后局面,参与全球性竞争的一项重要任务。 相似文献
53.
就当前我国正在运用的CAD/CAM软件特点做了归纳简介,提出使用我国自主版权的CAD/CAM系统软件已势在必行的观点,并认为其中的CAXA系列软件具有更多的优势,建议在科研、企业及高等职业技术教育中大力推广运用,以满足我国教学、科研和企业生产的发展需求。 相似文献
54.
结合企业异型件CAD/CAM系统的开发与应用实际,简要说明了应用CAD/CAM技术是实现烟草机械异型件国产化的必要途径,论述了CAD/CAM系统的开发所依据的技术原理和涉及到的关键技术问题,分析了应用该系统所产生的社会经济效益. 相似文献
55.
Simple and accurate closed‐form formulas obtained by using a differential evolution algorithm are presented for the synthesis of coplanar waveguides (CPW). The results of the synthesis formulas proposed in this article are compared with those of the quasi‐static analysis, the synthesis formulas reported by the other researchers and also the experimental works available in the literature. The accuracy of the proposed synthesis formulas is found to be better than 0.75% for 9256 CPWs samples. © 2008 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2008. 相似文献
56.
Multiresolution is currently one of the main schemes used in CAD modeling for representing objects, particularly when large-scale geometric data must be transferred interactively over a network, as in the case of collaborative design. Increasingly complex products and growing competition have turned design into a collaborative team effort. Furthermore, the widespread development of Internet viewers has also necessitated the transfer and display of large-scale CAD models over networks. In order to reduce the volume of transferred data, efforts have been made to transfer CSG (Constructive Solid Geometry) models rather than those based on B_rep (Boundary Representation). This paper presents an original new method for speeding up data transfer by using multiresolution CSG models at different levels of details (LOD). The multiresolution CSG algorithm generates a hierarchy of multiresolution CSG trees; at each level, the shape is further approximated and represented by a smaller number of CSG primitives. The paper analyzes the proposed algorithm, and demonstrates its feasibility. 相似文献
57.
在对等腰梯形焊管形状分析的基础上。精确计算了其周长,并在数学推导基础上,计算了各架次孔型尺寸,完成了等腰梯形焊管轧辊设计,使用结果表明;设计方法合理,孔型尺寸计算准确。使用效果良好。 相似文献
58.
59.
Computational models have been used widely in tissue engineering research and have proven to be powerful tools for bio-mechanical analysis (i.e., blood flow, growth models, drug delivery, etc). This paper focuses on developing higher-fidelity models for vascular structures and blood vessels that integrate computational shape representations with biomedical properties and features. Previous work in computer-aided vascular modeling comes from two communities. For those in biomedical imaging, the goal of past research has been to develop image understanding techniques for the interpretation of x-ray, magnetic resonance imaging (MRI), or other radiological data. These representations are predominantly discrete shape models that are not tied to physiological properties. The other corpus of existing work comes from those interested in developing physiological models for vascular growth and behavior based on bio-medical attributes. These models usually either have a highly simplified shape representation, or lack one entirely. Further, neither of these representations are suitable for the kind of interactive modeling required by tissue engineering applications.This paper aims to bridge these two approaches and develop a set of mathematical tools and algorithms for feature-based representation and computer-aided modeling of vascular trees for use in computer-aided tissue engineering applications. The paper offers a multi-scale representation based on swept volumes and a feature-based representation that can attribute the geometric representation with information about blood flow, pressure, and other biomedical properties. The paper shows how the resulting representation can be used as part of an overall approach for designing and visualizing vascular scaffolds. As a real-world example, we show how this computational model can be used to develop a tissue scaffold for liver tissue engineering. Such scaffolds may prove useful in a number of biomedical applications, including the growth of replacement tissue grafts and in vitro study of the pharmacological affects of new drugs on tissue cultures. 相似文献
60.
智能化的产品设计环境 总被引:6,自引:2,他引:4
随着计算机全面引入到产品设计全过程中,形成了计算机化的产品设计环境。本文深入分析产品设计过程中各种活动的演变规律及其信息处理方法,基于产品设计过程的进行模型理论,提出了智能化的产品设计环境IIIPDE的总体构思,分析了系统结构和信息流程。该系统具有较强的适应性,对分布式协同设计环境的构架也有适用性。本文最后总结了智能化产品设计环境中涉及到的关键技术环节和有待进一步研究的问题。 相似文献