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REVERSE MODELING FOR CONIC BLENDING FEATURE
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作者 Fan Shuqian Ke Yinglin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第4期482-489,共8页
A novel method to extract conic blending feature in reverse engineering is presented. Different from the methods to recover constant and variable radius blends from unorganized points, it contains not only novel segme... A novel method to extract conic blending feature in reverse engineering is presented. Different from the methods to recover constant and variable radius blends from unorganized points, it contains not only novel segmentation and feature recognition techniques, but also bias corrected technique to capture more reliable distribution of feature parameters along the spine curve. The segmentation depending on point classification separates the points in the conic blend region from the input point cloud. The available feature parameters of the cross-sectional curves are extracted with the processes of slicing point clouds with planes, conic curve fitting, and parameters estimation and compensation, The extracted parameters and its distribution laws are refined according to statistic theory such as regression analysis and hypothesis test. The proposed method can accurately capture the original design intentions and conveniently guide the reverse modeling process. Application examples are presented to verify the high precision and stability of the proposed method. 展开更多
关键词 Computer-aided design reverse engineering Feature recognition Geometric modeling Statistic theory Blending surface
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MODELING METHOD FOR PRODUCT STRUCTURE MAPPING BASED ON REVERSE SOLVING OF LOCUS AND MOTION 被引量:3
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作者 ZHANG Shuyou YI Guodong XU Xiaofeng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第5期114-119,共6页
Aiming at the problem of structure design in reverse-design of mechanism, a structure mapping method based on reverse solving of locus and motion (RSLM) is presented. The mechanism scheme meeting the requirements of... Aiming at the problem of structure design in reverse-design of mechanism, a structure mapping method based on reverse solving of locus and motion (RSLM) is presented. The mechanism scheme meeting the requirements of geometric and structural features is obtained through RSLM. The element instance subsets related to component are established based on the element type mapping, pair structure type mapping and design knowledge mapping between components and elements layer by layer. The assembly position mapping of elements is established based on the topological structure information of mechanism scheme, and the product modeling of structure mapping is realized. The algorithm program and prototype system of product structure mapping based on RSLM are developed. Application samples show that the method implements the integration of scheme design, assembly design and structure design, and modeling for product structure mapping based on RSLM. The feasibility of assembly is analyzed in scheme design that contributes to reducing the design error, and raising the design efficiency and quality. 展开更多
关键词 reverse solving Mapping Mechanism Assembly modeling
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NONLINEAR J-E CHARACTERISTICS IN THE ELECTRIC-THERMAL EQUILIBRIUM STATE FOR HIGH DENSITY POLYETHYLENE CONDUCTIVE COMPOSITES 被引量:2
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作者 Qiang Zheng Yi-hu Song Xiao-su Yi 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2001年第1期19-23,共5页
The nonlinear J-E characteristics under self-heating equilibrium for conductive composites based on high density polyethylene were studied. The results show that there are identical conduction mechanisms under self-he... The nonlinear J-E characteristics under self-heating equilibrium for conductive composites based on high density polyethylene were studied. The results show that there are identical conduction mechanisms under self-heating equilibrium for the composites with various initial resistivities determined by filler content or ambient temperature. The nonlinear conduction behavior was involved in the limited microstructure transformations of the conducting network induced by electrical field applied and the corresponding self-heating effect. A reversible thermal fuse (RTF) model was suggested to interpret the physical origin of the nonlinear J-E characteristics. 展开更多
关键词 J-E characteristics nonlinear conduction self-heating equilibrium reversible thermal fuse model
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A Spatio-temporal Data Model for Road Network in Data Center Based on Incremental Updating in Vehicle Navigation System 被引量:1
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作者 WU Huisheng LIU Zhaoli +1 位作者 ZHANG Shuwen ZUO Xiuling 《Chinese Geographical Science》 SCIE CSCD 2011年第3期346-353,共8页
The technique of incremental updating,which can better guarantee the real-time situation of navigational map,is the developing orientation of navigational road network updating.The data center of vehicle navigation sy... The technique of incremental updating,which can better guarantee the real-time situation of navigational map,is the developing orientation of navigational road network updating.The data center of vehicle navigation system is in charge of storing incremental data,and the spatio-temporal data model for storing incremental data does affect the efficiency of the response of the data center to the requirements of incremental data from the vehicle terminal.According to the analysis on the shortcomings of several typical spatio-temporal data models used in the data center and based on the base map with overlay model,the reverse map with overlay model (RMOM) was put forward for the data center to make rapid response to incremental data request.RMOM supports the data center to store not only the current complete road network data,but also the overlays of incremental data from the time when each road network changed to the current moment.Moreover,the storage mechanism and index structure of the incremental data were designed,and the implementation algorithm of RMOM was developed.Taking navigational road network in Guangzhou City as an example,the simulation test was conducted to validate the efficiency of RMOM.Results show that the navigation database in the data center can response to the requirements of incremental data by only one query with RMOM,and costs less time.Compared with the base map with overlay model,the data center does not need to temporarily overlay incremental data with RMOM,so time-consuming of response is significantly reduced.RMOM greatly improves the efficiency of response and provides strong support for the real-time situation of navigational road network. 展开更多
关键词 spatio-temporal data model reverse map with overlay model road network incremental updating vehicle navigation system data center vehicle terminal
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A New Mean Reversion Model of Close-End Fund
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作者 LIU Wei 《Wuhan University Journal of Natural Sciences》 CAS 2007年第3期447-451,共5页
On the basis of fractal theory, one of the nonlinear theories, this paper studies the validity of Chinese fund market fractal time sequence through Hurst exponent, calculates the H value and proposes a new close-end f... On the basis of fractal theory, one of the nonlinear theories, this paper studies the validity of Chinese fund market fractal time sequence through Hurst exponent, calculates the H value and proposes a new close-end fund mean reversion model. Meanwhile, this paper validates the mean reversion time sequence for consecutive 54 week data of fund market. The result indicates that this model can effectively prove that Chinese close-end fund market follows the biased random walk. The research also proves that the fund discount does have mean reversion tendency and averagely the fund with high discount has a higher excess yield than that of the fund with low discount. The mean excess yield and the ratio between discount rate deviation and standard deviation demonstrate a descending relationship. The optimum investment period based on "mean reversion" is one month. Consequently this model provides a new arbitrage method through the discount of close-end fund. 展开更多
关键词 close-end fund Hurst exponent mean reversion model arbitrage opportunity
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AN ENGINEERING MODEL FOR MULTICOMPONENT REVERSIBLE REACTION NETWORK
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作者 朱开宏 陈敏恒 袁渭康 《Chinese Journal of Chemical Engineering》 SCIE EI CAS 1985年第1期48-62,共15页
The treatment of a multicomponent reversible reaction network is extremely complicated because largenumber of rate constants must be precisely determined and because the calculation based on these rateconstants is ted... The treatment of a multicomponent reversible reaction network is extremely complicated because largenumber of rate constants must be precisely determined and because the calculation based on these rateconstants is tedious.In order to reduce the degrees of freedom of the process,the authors propose a methodin which the reactor and the separator are regarded as a whole.Based on this approach,an N-componentreversible reaction system can be dealt with as a two—component system.Consequently,a simple and ac-cessible way of the apparent rate determination is suggested.For fiist-order reactions,an explicit,simplifiedexpression has been derived for both lumped and distributed parameter reaction systems. 展开更多
关键词 CSTR ENG AN ENGINEERING MODEL FOR MULTICOMPONENT REVERSIBLE REACTION NETWORK CR IND
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Study on Project Progress Curve Model
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作者 Ding Shibao 《Engineering Sciences》 EI 2008年第1期74-77,共4页
Because of the discrepancy of project types,the project progress curves present different characteristics.Studying project progress curves can reduce management risk of project and overall grasp the enforcement condit... Because of the discrepancy of project types,the project progress curves present different characteristics.Studying project progress curves can reduce management risk of project and overall grasp the enforcement condition of the project.Combining project characteristic,this paper reaches 4 kinds of project progress curve patterns.If the front of the progress curve is concave,and its rear is protruding in the break point,it is named as S model.If its front is protruding and its rear is concave in the break point,it is named as the reverse side of S model.If the front and rear are concave in the break point,it is named as J model,and two half sections are both upward protruding,it is named as the reverse side of J model.Through a case study,it shows that application project progress curve model can better raise project management. 展开更多
关键词 progress curve model reverse side of S model reverse side of J model
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A Modified Lattice Model of the Reversible Effect of Axial Strain on the Critical Current of Polycrystalline REBa2Cu3O7-δ Films
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作者 苟晓凡 朱光 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第3期128-132,共5页
The strain effect on the critical current is one of the most important properties for polycrystalline YBa2 Cu3O7-δ (REBCO, RE: rare earth) films, in which the reversible effect is intrinsic in the range of strain ... The strain effect on the critical current is one of the most important properties for polycrystalline YBa2 Cu3O7-δ (REBCO, RE: rare earth) films, in which the reversible effect is intrinsic in the range of strain 0 and the irreversible strain εirr. By introducing the applied strain, a modified grain boundaries (GBs) in the REBCO film is developed. lattice model combining the strain and misorientation of A good agreement of the calculation on the lattice model with the experimental data shows that the lattice model is able to well describe the reversible effect of axial strain on the critical current of the REBCO film, and provides a good understanding of the mechanism of the reversible effect of the strain. Moreover, the effects of the crystallographic texture of the REBCO film and the residual strain εr on the variation of the critical current with the applied strain are extensively investigated. Furthermore by using the developed lattice model, the irreversible strain εirr of the REBCO film can be theoretically determined by comparing the calculation of the critical current-strain curve with the experimental data. 展开更多
关键词 REBCO A Modified Lattice Model of the Reversible Effect of Axial Strain on the Critical Current of Polycrystalline REBa2Cu3O FILMS Cu
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Managing economic and social profit of cooperative models in three-echelon reverse supply chain for waste electrical and electronic equipment 被引量:1
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作者 Jian Li Zhen Wang Bao Jiang 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2017年第5期125-134,共10页
In addition to maximizing economic benefits, reverse supply chains should further seek to maximize social benefits by increasing the quantity of waste electrical and electronic equipment (WEEE). The paper investigat... In addition to maximizing economic benefits, reverse supply chains should further seek to maximize social benefits by increasing the quantity of waste electrical and electronic equipment (WEEE). The paper investigates cooperative models with different parties in a three-echelon reverse supply chain for WEEE consisting of a single collector, a single remanufacturer, and two retailers based on complete information. In acldition, the optimal decisions of four cooperative models and the effect of the market demand of remanufactured WEEE products and the market share of two retailers on the optimal decisions are discussed. The results indicate that optimal total channel profit and recycle quantity in a reverse supply chain are maximized in a centralized model. The optimal total channel profit and recycle quantity increase with an increase in the market demand of remanufactured WEEE products. The three-echelon reverse supply chain consisting of duopolistic retailers maximizes total channel profit and recycle quantity in a reverse supply chain fbr WEEE. 展开更多
关键词 Waste electrical and electronic equipment(WEEE)reverse supply chains Recycle quantitySocial benefit Cooperative models Duopolistic retailers
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Reversible spiking neural P systems 被引量:1
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作者 Tao SONG Xiaolong SHI Jinbang XU 《Frontiers of Computer Science》 SCIE EI CSCD 2013年第3期350-358,共9页
Spiking neural (SN) P systems are a class of distributed parallel computing devices inspired by the way neurons communicate by means of spikes. In this work, we investigate reversibility in SN P systems, as well as ... Spiking neural (SN) P systems are a class of distributed parallel computing devices inspired by the way neurons communicate by means of spikes. In this work, we investigate reversibility in SN P systems, as well as the computing power of reversible SN P systems. Reversible SN P systems are proved to have Turing creativity, that is, they can compute any recursively enumerable set of non-negative integers by simulating universal reversible register machine. 展开更多
关键词 membrane computing spiking neural P system reversible computing model UNIVERSALITY reversible register machine
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Experimental Study on Medium and Low Cycle Fatigue Properties of Cast Steel GS20Mn5V
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作者 JIN Hui MO Jianhua +1 位作者 SUN Sijia ZHAO Jing 《Journal of Shanghai Jiaotong university(Science)》 EI 2021年第6期765-773,共9页
Owing to the remarkable advantages in mechanical behavior,cast steel nodes have been widely used in static structures.Nowadays,cast steel nodes also gain increasing popularity due to the superior fatigue performance i... Owing to the remarkable advantages in mechanical behavior,cast steel nodes have been widely used in static structures.Nowadays,cast steel nodes also gain increasing popularity due to the superior fatigue performance in dynamic structures,but they are not yet widely used because the fatigue properties of cast steel are not well understood.In this paper,the fatigue test of cast steel GS20Mn5V commonly used in steel castings is carried out.The strength of medium and low cycle fatigue and the fatigue limit are obtained.The feasibility of the estimated S-N(fatigue stress versus life)curve is tested.The double logarithmic linear model(DLLM)and the reversed generalized Pareto model(RGPM)are used to fit the experimental data,and the comparison is made.The P-S-N(the relationship between fatigue stress and life at different survival rates)curve obtained by the RGPM is proposed.The results show that the estimated S-N curve is not suitable for low cycle fatigue life,fitting the experimental data with the RGPM is the best,and obtaining the P-S-N curve from the RGPM is feasible. 展开更多
关键词 cast steel GS20Mn5V fatigue test double logarithmic linear model(DLLM) reversed generalize Pareto model(RGPM) S-N curve P-S-N curve
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