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
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
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
The geometry of each worn part is unique, so that a repair has to be tailored to each part individually. To ensure that a high quality repair is carried out, tool paths have to be generated adaptively for the tmique g...The geometry of each worn part is unique, so that a repair has to be tailored to each part individually. To ensure that a high quality repair is carried out, tool paths have to be generated adaptively for the tmique geometry and pose of the part being repaired. A polygonal modelling approach is introduced to rapidly construct a geometric model of the part to be repaired, together with a defect-free model with identical geometry and poise. The two models are compared so that the defects are identified for direct use by the laser cladding, machining and inspection processes.展开更多
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
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
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
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
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
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
基金This project is supported by General Electric Company and National Advanced Technology Project of China(No.863-511-942-018).
文摘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.
基金This project is supported by National Hi-tech Research Development Program of China(863 Program,No.2006AA04ZlI4)Research Fund for the Doctoral Program of Higher Education,China(No.20040335060)Zhejiang Provincial Scientific Personnel Educational Foundation,China(No.R603240).
文摘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.
基金the National Advanced Material Committee of China (NAMCC),国家自然科学基金
文摘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.
基金supported by National Natural Science Foundation of China(No. 50675040)Science and Technology R&D Project of Guangdong Province, China (No. 2006A10405005, No. 2007A010300015)Scientific Research Foundation for the Returned Overseas Chinese Scholars, Ministry of Education of China.
文摘The geometry of each worn part is unique, so that a repair has to be tailored to each part individually. To ensure that a high quality repair is carried out, tool paths have to be generated adaptively for the tmique geometry and pose of the part being repaired. A polygonal modelling approach is introduced to rapidly construct a geometric model of the part to be repaired, together with a defect-free model with identical geometry and poise. The two models are compared so that the defects are identified for direct use by the laser cladding, machining and inspection processes.
基金Supported by Chenguang Plan Project of Science and Technology Bureau in Wuhan (20065004116-11)
文摘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.
文摘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.
基金Supported by the National Natural Science Foundation of China under Grant No 11372096the Research Fund for the Doctoral Program of Higher Education of China
文摘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.
基金This work was supported by the National Natural Science Foundation of China (Grant No. 71471105).
文摘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.
基金This work was supported by the National Natural Science Foundation of China (Grant Nos. 61033003, 91130034, 61170183, 61100145, 61272071), PhD Programs Foundation of Ministry of Education of China (20100142110072, 20120142130008), National Science Foundation of Hubei Province (2011CDA027), and Scientific Research Foundation for the Excellent Middle-Aged and Youth Scientists of Shandong Province of China (BS2011SW025).
文摘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.
基金the National Key Research and Development Program of China(No.2017YFC0805100)the National Natural Science Foundation of China(No.51578137)+1 种基金the Priority Academic Program Development of the Jiangsu Higher Education Institutionsthe Open Research Fund Program of Jiangsu Key Laboratory of Engineering Mechanics。
文摘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.