The purpose of computer-aided design of new adaptive pulsed arc technologies of welding is: to de- sign optimum algorithms of pulsed control over main energy parameters of welding.It permits:to in- crease welding ...The purpose of computer-aided design of new adaptive pulsed arc technologies of welding is: to de- sign optimum algorithms of pulsed control over main energy parameters of welding.It permits:to in- crease welding productivity, to stabilize the welding regime, to control weld formation,taking into ac- count its spatial position, to proveal specie strength of the welded and coatings. Computer- aided design reduces the time of development of new pulsed arc technology:provides the optimization of technological referes according to the operating conditions of welded joints,the prediction of the ser- vice life of the welds.The developed methodology of computer-aided design of advanced technologies, models, original software, adaptive algorithms of pulsed control, and spend equipment permits to regulate penetration,the weld shape, the sizes of heat - affected zone; to predict sired properties and quality of welded joints.展开更多
This paper attempts to set a unified scene for various linear time-invariant (LTI) control system design schemes, by transforming the existing concept of “computer-aided control system design” (CACSD) to novel “com...This paper attempts to set a unified scene for various linear time-invariant (LTI) control system design schemes, by transforming the existing concept of “computer-aided control system design” (CACSD) to novel “computer-automated control system design” (CAutoCSD). The first step towards this goal is to accommodate, under practical constraints, various design objectives that are desirable in both time and frequency domains. Such performance-prioritised unification is aimed at relieving practising engineers from having to select a particular control scheme and from sacrificing certain performance goals resulting from pre-commitment to such schemes. With recent progress in evolutionary computing based extra-numeric, multi-criterion search and optimisation techniques, such unification of LTI control schemes becomes feasible, analytical and practical, and the resultant designs can be creative. The techniques developed are applied to, and illustrated by, three design problems. The unified approach automatically provides an integrator for zero-steady state error in velocity control of a DC motor, and meets multiple objectives in the design of an LTI controller for a non-minimum phase plant and offers a high-performance LTI controller network for a non-linear chemical process.展开更多
Based on the case-based designing (CBD), it is presented that the similarity of the fixtures is described by the fixture information of workpiece and the structure information of feature. Then, the computer-aided fixt...Based on the case-based designing (CBD), it is presented that the similarity of the fixtures is described by the fixture information of workpiece and the structure information of feature. Then, the computer-aided fixture design system is created on case-based reasoning (CBR), in which the attributes information of the main features of workpiece and structure of fixture as case index code are designed for the retrieve of the similar cases, and the structure and hierarchical relation of case library are set up for store. Meanwhile, the algorithm based on the knowledge-guided in the retrieve of the similar cases, the strategy of case adaptation and case storage in which the case identification number is used to distinguish from similar cases are presented. The application of the system in some projects improves the design efficiency and gets a good result.展开更多
This paper addresses linear time algorithms for parallel machine scheduling problems. We introduce a kind of threshold algorithms and discuss their main features. Three linear time threshold algorithm classes DT, PT a...This paper addresses linear time algorithms for parallel machine scheduling problems. We introduce a kind of threshold algorithms and discuss their main features. Three linear time threshold algorithm classes DT, PT and DTm are studied thoroughly. For all classes, we study their best possible algorithms among each class. We also present their application to several scheduling problems, The new algorithms are better than classical algorithms in time complexity and/or worst-case ratio. Computer-aided proof technique is used in the proof of main results, which greatly simplifies the proof and decreases case by case analysis.展开更多
A simple robust ＂strut algorithm＂ is presented which, when given a graph embedded in 3D space, thickens its edges into solid struts. Various applications, crystallographic and sculptural, are shown in which smooth h...A simple robust ＂strut algorithm＂ is presented which, when given a graph embedded in 3D space, thickens its edges into solid struts. Various applications, crystallographic and sculptural, are shown in which smooth high-genus forms are the output. A toolbox of algorithmic techniques allow for a variety of novel, visually engaging forms that express a mathematical aesthetic. In sculptural examples, hyperbolic tessellations in the Poincare plane are transformed in several ways to three-dimensional networks of edges embodied within a plausibly organic organization. By the use of different transformations and adjustable parameters in the algorithms, a variety of attractive forms result. The techniques produce watertight boundary representations that can be built with solid freeform fabrication equipment. The final physical output satisfies the ＂coolness criterion,＂ that passers by will pick them up and say ＂Wow, that＇s cool!＂展开更多
A robust and efficient algorithm is presented to build multiresolution models (MRMs) of arbitrary meshes without requirement of subdivision connectivity. To overcome the sampling difficulty of arbitrary meshes, edge c...A robust and efficient algorithm is presented to build multiresolution models (MRMs) of arbitrary meshes without requirement of subdivision connectivity. To overcome the sampling difficulty of arbitrary meshes, edge contraction and vertex expansion are used as downsampling and upsampling methods. Our MRMs of a mesh are composed of a base mesh and a series of edge split operations, which are organized as a directed graph. Each split operation encodes two parts of information. One is the modification to the mesh, and the other is the dependency relation among splits. Such organization ensures the efficiency and robustness of our MRM algorithm. Examples demonstrate the functionality of our method.展开更多
通过对现有报文分类算法的分析和性能比较,并结合分类规则所具有的特性提出了一种新的基于IXP1200网络处理器的多维报文分类算法,称为PCBNP(packet classification based on network processor),并达到了报文的线速转发.算法除了通过减...通过对现有报文分类算法的分析和性能比较,并结合分类规则所具有的特性提出了一种新的基于IXP1200网络处理器的多维报文分类算法,称为PCBNP(packet classification based on network processor),并达到了报文的线速转发.算法除了通过减少分类的规则数和分类的域宽来加快分类的速度外,还采用重定向排序索引、位向量表示匹配规则等技术来加快分类的速度,特别是利用了规则的动态分布规律来确定查找报文字段的顺序,通过先查找“分布最均匀的字段”来达到在所有的字段被查找之前提前找到报文匹配的过滤规则的目的.算法具有高速、多维和可扩展的特性,与现有的算法比较,该算法在综合性能上优于已有的报文分类算法.展开更多
文摘The purpose of computer-aided design of new adaptive pulsed arc technologies of welding is: to de- sign optimum algorithms of pulsed control over main energy parameters of welding.It permits:to in- crease welding productivity, to stabilize the welding regime, to control weld formation,taking into ac- count its spatial position, to proveal specie strength of the welded and coatings. Computer- aided design reduces the time of development of new pulsed arc technology:provides the optimization of technological referes according to the operating conditions of welded joints,the prediction of the ser- vice life of the welds.The developed methodology of computer-aided design of advanced technologies, models, original software, adaptive algorithms of pulsed control, and spend equipment permits to regulate penetration,the weld shape, the sizes of heat - affected zone; to predict sired properties and quality of welded joints.
文摘This paper attempts to set a unified scene for various linear time-invariant (LTI) control system design schemes, by transforming the existing concept of “computer-aided control system design” (CACSD) to novel “computer-automated control system design” (CAutoCSD). The first step towards this goal is to accommodate, under practical constraints, various design objectives that are desirable in both time and frequency domains. Such performance-prioritised unification is aimed at relieving practising engineers from having to select a particular control scheme and from sacrificing certain performance goals resulting from pre-commitment to such schemes. With recent progress in evolutionary computing based extra-numeric, multi-criterion search and optimisation techniques, such unification of LTI control schemes becomes feasible, analytical and practical, and the resultant designs can be creative. The techniques developed are applied to, and illustrated by, three design problems. The unified approach automatically provides an integrator for zero-steady state error in velocity control of a DC motor, and meets multiple objectives in the design of an LTI controller for a non-minimum phase plant and offers a high-performance LTI controller network for a non-linear chemical process.
基金TheNationalHighTechnologyResearchandDevelopmentProgramofChina ( 863Program ) (No .2 0 0 2AA4110 3 0 ) ,theNaturalScientificResearchProgramCollegeofUniversityofJiangsuProvince (No .0 3KJD5 2 0 2 46)
文摘Based on the case-based designing (CBD), it is presented that the similarity of the fixtures is described by the fixture information of workpiece and the structure information of feature. Then, the computer-aided fixture design system is created on case-based reasoning (CBR), in which the attributes information of the main features of workpiece and structure of fixture as case index code are designed for the retrieve of the similar cases, and the structure and hierarchical relation of case library are set up for store. Meanwhile, the algorithm based on the knowledge-guided in the retrieve of the similar cases, the strategy of case adaptation and case storage in which the case identification number is used to distinguish from similar cases are presented. The application of the system in some projects improves the design efficiency and gets a good result.
基金the National Natural Science Foundation of China(10301028,60021201)A preliminary version of this paper appeared in the proceedings of the 1st International Conference on Algorithmic Applications in Management,Lecture Notes in Computer Science 3521
文摘This paper addresses linear time algorithms for parallel machine scheduling problems. We introduce a kind of threshold algorithms and discuss their main features. Three linear time threshold algorithm classes DT, PT and DTm are studied thoroughly. For all classes, we study their best possible algorithms among each class. We also present their application to several scheduling problems, The new algorithms are better than classical algorithms in time complexity and/or worst-case ratio. Computer-aided proof technique is used in the proof of main results, which greatly simplifies the proof and decreases case by case analysis.
文摘A simple robust ＂strut algorithm＂ is presented which, when given a graph embedded in 3D space, thickens its edges into solid struts. Various applications, crystallographic and sculptural, are shown in which smooth high-genus forms are the output. A toolbox of algorithmic techniques allow for a variety of novel, visually engaging forms that express a mathematical aesthetic. In sculptural examples, hyperbolic tessellations in the Poincare plane are transformed in several ways to three-dimensional networks of edges embodied within a plausibly organic organization. By the use of different transformations and adjustable parameters in the algorithms, a variety of attractive forms result. The techniques produce watertight boundary representations that can be built with solid freeform fabrication equipment. The final physical output satisfies the ＂coolness criterion,＂ that passers by will pick them up and say ＂Wow, that＇s cool!＂
文摘A robust and efficient algorithm is presented to build multiresolution models (MRMs) of arbitrary meshes without requirement of subdivision connectivity. To overcome the sampling difficulty of arbitrary meshes, edge contraction and vertex expansion are used as downsampling and upsampling methods. Our MRMs of a mesh are composed of a base mesh and a series of edge split operations, which are organized as a directed graph. Each split operation encodes two parts of information. One is the modification to the mesh, and the other is the dependency relation among splits. Such organization ensures the efficiency and robustness of our MRM algorithm. Examples demonstrate the functionality of our method.
文摘通过对现有报文分类算法的分析和性能比较,并结合分类规则所具有的特性提出了一种新的基于IXP1200网络处理器的多维报文分类算法,称为PCBNP(packet classification based on network processor),并达到了报文的线速转发.算法除了通过减少分类的规则数和分类的域宽来加快分类的速度外,还采用重定向排序索引、位向量表示匹配规则等技术来加快分类的速度,特别是利用了规则的动态分布规律来确定查找报文字段的顺序,通过先查找“分布最均匀的字段”来达到在所有的字段被查找之前提前找到报文匹配的过滤规则的目的.算法具有高速、多维和可扩展的特性,与现有的算法比较,该算法在综合性能上优于已有的报文分类算法.
