[Objective] To discuss the effects of major mapping methods for DNA sequence on the accuracy of protein coding regions prediction,and to find out the effective mapping methods.[Method] By taking Approximate Correlatio...[Objective] To discuss the effects of major mapping methods for DNA sequence on the accuracy of protein coding regions prediction,and to find out the effective mapping methods.[Method] By taking Approximate Correlation(AC) as the full measure of the prediction accuracy at nucleotide level,the windowed narrow pass-band filter(WNPBF) based prediction algorithm was applied to study the effects of different mapping methods on prediction accuracy.[Result] In DNA data sets ALLSEQ and HMR195,the Voss and Z-Curve methods are proved to be more effective mapping methods than paired numeric(PN),Electron-ion Interaction Potential(EIIP) and complex number methods.[Conclusion] This study lays the foundation to verify the effectiveness of new mapping methods by using the predicted AC value,and it is meaningful to reveal DNA structure by using bioinformatics methods.展开更多
This paper studies the cascading failure on random networks and scale-free networks by introducing the tolerance parameter of edge based on the coupled map lattices methods. The whole work focuses on investigating som...This paper studies the cascading failure on random networks and scale-free networks by introducing the tolerance parameter of edge based on the coupled map lattices methods. The whole work focuses on investigating some indices including the number of failed edges, dynamic edge tolerance capacity and the perturbation of edge. In general, it assumes that the perturbation is attributed to the normal distribution in adopted simulations. By investigating the effectiveness of edge tolerance in scale-free and random networks, it finds that the larger tolerance parameter λ can more efficiently delay the cascading failure process for scale-free networks than random networks. These results indicate that the cascading failure process can be effectively controlled by increasing the tolerance parameter λ. Moreover, the simulations also show that, larger variance of perturbation can easily trigger the cascading failures than the smaller one. This study may be useful for evaluating efficiency of whole traffic systems, and for alleviating cascading failure in such systems.展开更多
Fatigue failure is a common failure mode under the action of cyclic loads in engineering applications,which often occurs with no obvious signal.The maximum structural stress is far below the allowable stress when the ...Fatigue failure is a common failure mode under the action of cyclic loads in engineering applications,which often occurs with no obvious signal.The maximum structural stress is far below the allowable stress when the structures are damaged.Aiming at the lightweight structure,fatigue topology optimization design is investigated to avoid the occurrence of fatigue failure in the structural conceptual design beforehand.Firstly,the fatigue life is expressed by topology variables and the fatigue life filter function.The continuum fatigue optimization model is established with the independent continuous mapping(ICM)method.Secondly,fatigue life constraints are transformed to distortion energy constraints explicitly by taking advantage of the distortion energy theory.Thirdly,the optimization formulation is solved by the dual sequence quadratic programming(DSQP).And the design scheme of lightweight structure considering the fatigue characteristics is obtained.Finally,numerical examples illustrate the practicality and effectiveness of the fatigue optimization method.This method further expands the theoretical application of the ICM method and provides a novel approach for the fatigue optimization problem.展开更多
A physical value mapping (PVM) algorithm based on finite element mesh from the stamped part in stamping process to the product is presented, In order to improve the efficiency of the PVM algorithm, a search way from...A physical value mapping (PVM) algorithm based on finite element mesh from the stamped part in stamping process to the product is presented, In order to improve the efficiency of the PVM algorithm, a search way from the mesh of the product to the mesh of the stamped part will be adopted. At the same time, the search process is divided into two steps: entire search (ES) and local search (LS), which improve the searching efficiency. The searching area is enlarged to avoid missing projection elements in ES process. An arc-length method is introduced in LS process. The validity is confirmed by the results of the complex industry-forming product.展开更多
In this paper, by means of the variable-coefficient mapping method based on elliptical equation, we obtain explicit solutions of nonlinear Schrodinger equation with variable-coefficient. These solutions include Jacobi...In this paper, by means of the variable-coefficient mapping method based on elliptical equation, we obtain explicit solutions of nonlinear Schrodinger equation with variable-coefficient. These solutions include Jacobian elliptic function solutions, solitary wave solutions, soliton-like solutions, and trigonometric function solutions, among which some are found for the first time. Six figures are given to illustrate some features of these solutions. The method can be applied to other nonlinear evolution equations in mathematical physics.展开更多
In order to support just-in-time reconfiguration of business process execution language (BPEL) process, a template-based mapping method is proposed to map business level process to BPEL process. The method builds up...In order to support just-in-time reconfiguration of business process execution language (BPEL) process, a template-based mapping method is proposed to map business level process to BPEL process. The method builds up mapping relationships between the key points of business level process and BPEL process, which helps users to adjust the business level process with simplified operations, and automatically maps the changes to BPEL. In addition, a case of the application of the method in a clothing enterprise was illustrated.展开更多
In this paper, we extend the mapping transformation method through introducing variable coefficients.By means of the extended mapping transformation method, many explicit and exact general solutions with arbitrary fun...In this paper, we extend the mapping transformation method through introducing variable coefficients.By means of the extended mapping transformation method, many explicit and exact general solutions with arbitrary functions for some nonlinear partial differential equations, which contain solitary wave solutions, trigonometric function solutions, and rational solutions, are obtained.展开更多
This paper proposes a new rapid and efficient method for woolen textile simulation- mapping synthesize. This method uses a stochastic function to simulate fuzz on some types of wool textile. The wool yarns are simulat...This paper proposes a new rapid and efficient method for woolen textile simulation- mapping synthesize. This method uses a stochastic function to simulate fuzz on some types of wool textile. The wool yarns are simulated on the basis of Phong illumination model. In order to obtain a visual effect of the wool textile with fuzz, the light intensity of fuzz is synthesized as a color parameter in the Phong illumination model after the yams have been simulated. The model of woolen textile with fuzz can be built eventually.With synthesis mapping methods, user can choose his favorite fuzz density on the wool by controlling some appropriate parameters.展开更多
The stochastic response of a noisy system with non-negative restoring force is investigated. The generalized cell mapping (GCM) method compute the transient and stationary probability density functions (PDFs) real...The stochastic response of a noisy system with non-negative restoring force is investigated. The generalized cell mapping (GCM) method compute the transient and stationary probability density functions (PDFs) real-power is used to Combined with the global properties of the noise-free system, the evolutionary process of the tran- sient PDFs is revealed. The results show that stochastic P-bifurcation occurs when the system parameter varies in the response analysis and the stationary PDF evolves from bimodal to unimodal along the unstable manifold during the bifurcation.展开更多
Oil and gas exploration near faults in shallow strata is investigated in this study based on an analysis of oil-source faults in reservoire-cap rock combinations without a source rock.The oil-source faults were mapped...Oil and gas exploration near faults in shallow strata is investigated in this study based on an analysis of oil-source faults in reservoire-cap rock combinations without a source rock.The oil-source faults were mapped by superimposition of the distribution area of oil-source faults and the leakage area of cap rocks.This method is applied to the mapping of oil-source faults for two sets of reservoire-cap rock combinations without a source rock in the Banqiao area of the Qikou Sag in the Bohai Bay Basin,eastern China.Combination B is formed by a mudstone cap rock of the middle sub-member of the 1st member of the Shahejie Formation(E3s1 M)with its underlying reservoir,while Combination C is formed by a mudstone cap rock of the 2nd member of the Dongying Formation(E_(3)d_(2))with its underlying reservoir.The results show that the oil-source faults of Combination B are relatively better developed and mainly occur in the northeast and southeast,while those of Combination C are not as well developed and are only distributed at the southeastern edge of the study area with a small proportion in the north.These results are consistent with the fact that oil and gas are mainly distributed near oil-source faults,proving the method proposed is workable in determining the oil-source faults in reservoire-cap rock combinations without a source rock.展开更多
A new system of set-valued variational inclusions involving generalized H(·, ·)-accretive mapping in real q-uniformly smooth Banach spaces is introduced, and then based on the generalized resolvent operato...A new system of set-valued variational inclusions involving generalized H(·, ·)-accretive mapping in real q-uniformly smooth Banach spaces is introduced, and then based on the generalized resolvent operator technique associated with H(·, ·)-accretivity, the existence and approximation solvability of solutions using an iterative algorithm is investigated.展开更多
Hydrogeological map is one of the important carriers of groundwater related information.It directly reflects the hydrogeological conditions and previous investigation and research results of a mapping area.The hydroge...Hydrogeological map is one of the important carriers of groundwater related information.It directly reflects the hydrogeological conditions and previous investigation and research results of a mapping area.The hydrogeological map of China is a map reflecting the characteristics of hydrogeology and groundwater dynamics on a national scale.On the basis of the hydrogeological map of China(1:4000000)compiled in 1988,this map compilation attempted to update and enhance the existing map,with the latest survey results from the project of National Investigation and Evaluation of Groundwater Resources and Environmental Problems led by China Geological Survey.Task of the mapping program included redefining groundwater types,quantifying the classification standard of the groundwater and adding the pore-fissure water in laterite layer of hilly basin.The multilayer structures for porous,karst and porous-fractured groundwater and their water-rich grades are reflected on the map.Based on the comprehensive summary of the latest hydrogeological data of China,this research conducts an in-depth analysis of the regional distribution characteristics of groundwater in China,utilizes a digital mapping process and establishes a cartographic database for the purpose of further use.With the enrichment of the content and the continuous improvement of cognitive level,mapping content can be updated quickly,which has practical significance for the concept of surveying and mapping and scientific popularization.展开更多
A crisis in a Duffing-van del Pol system with fuzzy uncertainties is studied by means of the fuzzy generalised cell mapping (FGCM) method. A crisis happens when two fuzzy attractors collide simultaneously with a fuz...A crisis in a Duffing-van del Pol system with fuzzy uncertainties is studied by means of the fuzzy generalised cell mapping (FGCM) method. A crisis happens when two fuzzy attractors collide simultaneously with a fuzzy saddle on the basin boundary as the intensity of fuzzy noise reaches a critical point. The two fuzzy attractors merge discontinuously to form one large fuzzy attractor after a crisis. A fuzzy attractor is characterized by its global topology and membership function. A fuzzy saddle with a complicated pattern of several disjoint segments is observed in phase space. It leads to a discontinuous merging crisis of fuzzy attractors. We illustrate this crisis event by considering a fixed point under additive and multiplicative fuzzy noise. Such a crisis is fuzzy noise-induced effects which cannot be seen in deterministic systems.展开更多
The present work introduces a novel concurrent optimization formulation to meet the requirements of lightweight design and various constraints simultaneously.Nodal displacement of macrostructure and effective thermal ...The present work introduces a novel concurrent optimization formulation to meet the requirements of lightweight design and various constraints simultaneously.Nodal displacement of macrostructure and effective thermal conductivity of microstructure are regarded as the constraint functions, which means taking into account both the loadcarrying capabilities and the thermal insulation properties.The effective properties of porous material derived from numerical homogenization are used for macrostructural analysis. Meanwhile, displacement vectors of macrostructures from original and adjoint load cases are used for sensitivity analysis of the microstructure. Design variables in the form of reciprocal functions of relative densities are introduced and used for linearization of the constraint function. The objective function of total mass is approximately expressed by the second order Taylor series expansion. Then, the proposed concurrent optimization problem is solved using a sequential quadratic programming algorithm, by splitting into a series of sub-problems in the form of the quadratic program. Finally, several numerical examples are presented to validate the effectiveness of the proposed optimization method. The various effects including initial designs, prescribed limits of nodal displacement, and effective thermal conductivity on optimized designs are also investigated. An amount of optimized macrostructures and their corresponding microstructures are achieved.展开更多
By using the modified mapping method, we find some new exact solutions of the generalized Boussinesq equation and the Boussinesq-Burgers equation. The solutions obtained in this paper include Jacobian elliptic functio...By using the modified mapping method, we find some new exact solutions of the generalized Boussinesq equation and the Boussinesq-Burgers equation. The solutions obtained in this paper include Jacobian elliptic function solutions, combined Jacobian elliptic function solutions, soliton solutions, triangular function solutions.展开更多
It is an important topic to improve the redundancy of optimized configuration to resist the local failure in topology optimization of continuum structures.Such a fail-safe topology optimization problem has been solved...It is an important topic to improve the redundancy of optimized configuration to resist the local failure in topology optimization of continuum structures.Such a fail-safe topology optimization problem has been solved effectively in the ficld of statics.In this paper,the fail-safe topology optimization problem is extended to the field of frequency topology optimization.Based on the independent continuous mapping(ICM)method,the model of fail-safe topology optimization is established with the objective of minimal weight integrating with the discrete condition of topological variables and the constraint of the fundamental frequency.The fail-safe optimization model established above is substituted by a sequence of subproblems in the form of the quadratic program with exact second-order information and solved efficiently by the dual sequence quadratic programming(DSQP)algorithm.The numerical result reveals that the optimized fail-safe structure has more complex configuration and preserved materials than the structure obtained from the traditional frequency topology optimization,which means that the optimized fail-safe structure has higher redundancy.Moreover,the optimized fail-safe structure guarantees that the natural frequency meets the constraint of fundamental frequency when the local failure ocurs,which can avoid the structural frequency to be sensitive to local failure.The fail-safe optimirzation topology model is proved effective and feasible by four numerical examples.展开更多
By making use of extended mapping method and auxiliary equation for finding new periodic wave solu tions of nonlinear evolution equations in mathematical physics, we obtain some new periodic wave solutions for general...By making use of extended mapping method and auxiliary equation for finding new periodic wave solu tions of nonlinear evolution equations in mathematical physics, we obtain some new periodic wave solutions for generalized Klein-Cordon equation and Benjamin equation, which cannot be found in previous work. This method also can be used to find new periodic wave solutions of other nonlinear evolution equations.展开更多
New exact solutions, expressed in terms of the Jacobi elliptic functions, to the nonlinear Klein-Gordon equation are obtained by using a modified mapping method. The solutions include the conditions for equation's pa...New exact solutions, expressed in terms of the Jacobi elliptic functions, to the nonlinear Klein-Gordon equation are obtained by using a modified mapping method. The solutions include the conditions for equation's parameters and travelling wave transformation parameters. Some figures for a specific kind of solution are also presented.展开更多
In this paper, we make use of the auxiliary equation and the expanded mapping methods to find the new exact periodic solutions for (2+1)-dimensional dispersive long wave equations in mathematical physics, which are...In this paper, we make use of the auxiliary equation and the expanded mapping methods to find the new exact periodic solutions for (2+1)-dimensional dispersive long wave equations in mathematical physics, which are expressed by Jacobi elliptic functions, and obtain some new solitary wave solutions (m → 1). This method can also be used to explore new periodic wave solutions for other nonlinear evolution equations.展开更多
基金Supported by Ningxia Natural Science Foundation (NZ1024)the Scientific Research the Project of Ningxia Universities (201027)~~
文摘[Objective] To discuss the effects of major mapping methods for DNA sequence on the accuracy of protein coding regions prediction,and to find out the effective mapping methods.[Method] By taking Approximate Correlation(AC) as the full measure of the prediction accuracy at nucleotide level,the windowed narrow pass-band filter(WNPBF) based prediction algorithm was applied to study the effects of different mapping methods on prediction accuracy.[Result] In DNA data sets ALLSEQ and HMR195,the Voss and Z-Curve methods are proved to be more effective mapping methods than paired numeric(PN),Electron-ion Interaction Potential(EIIP) and complex number methods.[Conclusion] This study lays the foundation to verify the effectiveness of new mapping methods by using the predicted AC value,and it is meaningful to reveal DNA structure by using bioinformatics methods.
基金supported by National Basic Research Program of China (Grant No 2006CB705500)Chang-Jiang Scholars and Innovative Research Team in University of China (Grant No IRT0605)the National Natural Science Foundation of China (Grant No70631001)
文摘This paper studies the cascading failure on random networks and scale-free networks by introducing the tolerance parameter of edge based on the coupled map lattices methods. The whole work focuses on investigating some indices including the number of failed edges, dynamic edge tolerance capacity and the perturbation of edge. In general, it assumes that the perturbation is attributed to the normal distribution in adopted simulations. By investigating the effectiveness of edge tolerance in scale-free and random networks, it finds that the larger tolerance parameter λ can more efficiently delay the cascading failure process for scale-free networks than random networks. These results indicate that the cascading failure process can be effectively controlled by increasing the tolerance parameter λ. Moreover, the simulations also show that, larger variance of perturbation can easily trigger the cascading failures than the smaller one. This study may be useful for evaluating efficiency of whole traffic systems, and for alleviating cascading failure in such systems.
基金This work was supported by the National Natural Science Foundation of China(11872080)Beijing Natural Science Foundation(3192005).
文摘Fatigue failure is a common failure mode under the action of cyclic loads in engineering applications,which often occurs with no obvious signal.The maximum structural stress is far below the allowable stress when the structures are damaged.Aiming at the lightweight structure,fatigue topology optimization design is investigated to avoid the occurrence of fatigue failure in the structural conceptual design beforehand.Firstly,the fatigue life is expressed by topology variables and the fatigue life filter function.The continuum fatigue optimization model is established with the independent continuous mapping(ICM)method.Secondly,fatigue life constraints are transformed to distortion energy constraints explicitly by taking advantage of the distortion energy theory.Thirdly,the optimization formulation is solved by the dual sequence quadratic programming(DSQP).And the design scheme of lightweight structure considering the fatigue characteristics is obtained.Finally,numerical examples illustrate the practicality and effectiveness of the fatigue optimization method.This method further expands the theoretical application of the ICM method and provides a novel approach for the fatigue optimization problem.
基金This project is supported by National Natural Science Foundation ofChina(No.l9832020) and National Outstanding Youth Science Foundation ofChina(No.10125208).
文摘A physical value mapping (PVM) algorithm based on finite element mesh from the stamped part in stamping process to the product is presented, In order to improve the efficiency of the PVM algorithm, a search way from the mesh of the product to the mesh of the stamped part will be adopted. At the same time, the search process is divided into two steps: entire search (ES) and local search (LS), which improve the searching efficiency. The searching area is enlarged to avoid missing projection elements in ES process. An arc-length method is introduced in LS process. The validity is confirmed by the results of the complex industry-forming product.
基金The project supported by the Natural Science Foundation of Zhejiang Province of China under Grant No. Y605312.
文摘In this paper, by means of the variable-coefficient mapping method based on elliptical equation, we obtain explicit solutions of nonlinear Schrodinger equation with variable-coefficient. These solutions include Jacobian elliptic function solutions, solitary wave solutions, soliton-like solutions, and trigonometric function solutions, among which some are found for the first time. Six figures are given to illustrate some features of these solutions. The method can be applied to other nonlinear evolution equations in mathematical physics.
基金the National High-Technology Research and Development Program of China (863 Program) (2006AA04Z158, 2006AA01A106)the National Basic Research Program of China (973 Program) (2005CB 321807, 2007CB310805)
文摘In order to support just-in-time reconfiguration of business process execution language (BPEL) process, a template-based mapping method is proposed to map business level process to BPEL process. The method builds up mapping relationships between the key points of business level process and BPEL process, which helps users to adjust the business level process with simplified operations, and automatically maps the changes to BPEL. In addition, a case of the application of the method in a clothing enterprise was illustrated.
文摘In this paper, we extend the mapping transformation method through introducing variable coefficients.By means of the extended mapping transformation method, many explicit and exact general solutions with arbitrary functions for some nonlinear partial differential equations, which contain solitary wave solutions, trigonometric function solutions, and rational solutions, are obtained.
文摘This paper proposes a new rapid and efficient method for woolen textile simulation- mapping synthesize. This method uses a stochastic function to simulate fuzz on some types of wool textile. The wool yarns are simulated on the basis of Phong illumination model. In order to obtain a visual effect of the wool textile with fuzz, the light intensity of fuzz is synthesized as a color parameter in the Phong illumination model after the yams have been simulated. The model of woolen textile with fuzz can be built eventually.With synthesis mapping methods, user can choose his favorite fuzz density on the wool by controlling some appropriate parameters.
基金Project supported by the National Natural Science Foundation of China(Nos.11172233,11302169,11302170,and 11472212)the Fundamental Research Funds for the Central Universities(No.3102014JCQ01079)
文摘The stochastic response of a noisy system with non-negative restoring force is investigated. The generalized cell mapping (GCM) method compute the transient and stationary probability density functions (PDFs) real-power is used to Combined with the global properties of the noise-free system, the evolutionary process of the tran- sient PDFs is revealed. The results show that stochastic P-bifurcation occurs when the system parameter varies in the response analysis and the stationary PDF evolves from bimodal to unimodal along the unstable manifold during the bifurcation.
基金The National Natural Science Foundation of China(grant IDs 41872157,42072157).
文摘Oil and gas exploration near faults in shallow strata is investigated in this study based on an analysis of oil-source faults in reservoire-cap rock combinations without a source rock.The oil-source faults were mapped by superimposition of the distribution area of oil-source faults and the leakage area of cap rocks.This method is applied to the mapping of oil-source faults for two sets of reservoire-cap rock combinations without a source rock in the Banqiao area of the Qikou Sag in the Bohai Bay Basin,eastern China.Combination B is formed by a mudstone cap rock of the middle sub-member of the 1st member of the Shahejie Formation(E3s1 M)with its underlying reservoir,while Combination C is formed by a mudstone cap rock of the 2nd member of the Dongying Formation(E_(3)d_(2))with its underlying reservoir.The results show that the oil-source faults of Combination B are relatively better developed and mainly occur in the northeast and southeast,while those of Combination C are not as well developed and are only distributed at the southeastern edge of the study area with a small proportion in the north.These results are consistent with the fact that oil and gas are mainly distributed near oil-source faults,proving the method proposed is workable in determining the oil-source faults in reservoire-cap rock combinations without a source rock.
基金Supported by the National Natural Science Foundation of China(Grant No.11371015)the Key Project of Chinese Ministry of Education(Grant No.211163)+3 种基金Sichuan Youth Science and Technology Foundation(GrantNo.2012JQ0032)the Foundation of China West Normal University(Grant No.11A028,11A029)the Fundamental Research Funds of China West Normal University(Grant No.13D016)the Natural Science Foundation ofSichuan Provincial Education Department(Grant No.14ZB0142)
文摘A new system of set-valued variational inclusions involving generalized H(·, ·)-accretive mapping in real q-uniformly smooth Banach spaces is introduced, and then based on the generalized resolvent operator technique associated with H(·, ·)-accretivity, the existence and approximation solvability of solutions using an iterative algorithm is investigated.
文摘Hydrogeological map is one of the important carriers of groundwater related information.It directly reflects the hydrogeological conditions and previous investigation and research results of a mapping area.The hydrogeological map of China is a map reflecting the characteristics of hydrogeology and groundwater dynamics on a national scale.On the basis of the hydrogeological map of China(1:4000000)compiled in 1988,this map compilation attempted to update and enhance the existing map,with the latest survey results from the project of National Investigation and Evaluation of Groundwater Resources and Environmental Problems led by China Geological Survey.Task of the mapping program included redefining groundwater types,quantifying the classification standard of the groundwater and adding the pore-fissure water in laterite layer of hilly basin.The multilayer structures for porous,karst and porous-fractured groundwater and their water-rich grades are reflected on the map.Based on the comprehensive summary of the latest hydrogeological data of China,this research conducts an in-depth analysis of the regional distribution characteristics of groundwater in China,utilizes a digital mapping process and establishes a cartographic database for the purpose of further use.With the enrichment of the content and the continuous improvement of cognitive level,mapping content can be updated quickly,which has practical significance for the concept of surveying and mapping and scientific popularization.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 10772140 and 10872155)
文摘A crisis in a Duffing-van del Pol system with fuzzy uncertainties is studied by means of the fuzzy generalised cell mapping (FGCM) method. A crisis happens when two fuzzy attractors collide simultaneously with a fuzzy saddle on the basin boundary as the intensity of fuzzy noise reaches a critical point. The two fuzzy attractors merge discontinuously to form one large fuzzy attractor after a crisis. A fuzzy attractor is characterized by its global topology and membership function. A fuzzy saddle with a complicated pattern of several disjoint segments is observed in phase space. It leads to a discontinuous merging crisis of fuzzy attractors. We illustrate this crisis event by considering a fixed point under additive and multiplicative fuzzy noise. Such a crisis is fuzzy noise-induced effects which cannot be seen in deterministic systems.
基金supported by the National Natural Science Foundation of China (Grants 11202078, 51405123)the Fundamental Research Funds for the Central Universities (Grant 2017MS077)
文摘The present work introduces a novel concurrent optimization formulation to meet the requirements of lightweight design and various constraints simultaneously.Nodal displacement of macrostructure and effective thermal conductivity of microstructure are regarded as the constraint functions, which means taking into account both the loadcarrying capabilities and the thermal insulation properties.The effective properties of porous material derived from numerical homogenization are used for macrostructural analysis. Meanwhile, displacement vectors of macrostructures from original and adjoint load cases are used for sensitivity analysis of the microstructure. Design variables in the form of reciprocal functions of relative densities are introduced and used for linearization of the constraint function. The objective function of total mass is approximately expressed by the second order Taylor series expansion. Then, the proposed concurrent optimization problem is solved using a sequential quadratic programming algorithm, by splitting into a series of sub-problems in the form of the quadratic program. Finally, several numerical examples are presented to validate the effectiveness of the proposed optimization method. The various effects including initial designs, prescribed limits of nodal displacement, and effective thermal conductivity on optimized designs are also investigated. An amount of optimized macrostructures and their corresponding microstructures are achieved.
基金Project supported by the State Key Program for Basic Research of China (Grant No 2004CB418304)the National Natural Science Foundation of China (Grant No 40405010)
文摘By using the modified mapping method, we find some new exact solutions of the generalized Boussinesq equation and the Boussinesq-Burgers equation. The solutions obtained in this paper include Jacobian elliptic function solutions, combined Jacobian elliptic function solutions, soliton solutions, triangular function solutions.
基金the National Natural Science Foundation of China(Grant 11872080).
文摘It is an important topic to improve the redundancy of optimized configuration to resist the local failure in topology optimization of continuum structures.Such a fail-safe topology optimization problem has been solved effectively in the ficld of statics.In this paper,the fail-safe topology optimization problem is extended to the field of frequency topology optimization.Based on the independent continuous mapping(ICM)method,the model of fail-safe topology optimization is established with the objective of minimal weight integrating with the discrete condition of topological variables and the constraint of the fundamental frequency.The fail-safe optimization model established above is substituted by a sequence of subproblems in the form of the quadratic program with exact second-order information and solved efficiently by the dual sequence quadratic programming(DSQP)algorithm.The numerical result reveals that the optimized fail-safe structure has more complex configuration and preserved materials than the structure obtained from the traditional frequency topology optimization,which means that the optimized fail-safe structure has higher redundancy.Moreover,the optimized fail-safe structure guarantees that the natural frequency meets the constraint of fundamental frequency when the local failure ocurs,which can avoid the structural frequency to be sensitive to local failure.The fail-safe optimirzation topology model is proved effective and feasible by four numerical examples.
基金The project supported by the Natural Science Foundation of Anhui Province of China under Grant No. 01041188 and the Foundation of Classical Courses of Anhui Province
文摘By making use of extended mapping method and auxiliary equation for finding new periodic wave solu tions of nonlinear evolution equations in mathematical physics, we obtain some new periodic wave solutions for generalized Klein-Cordon equation and Benjamin equation, which cannot be found in previous work. This method also can be used to find new periodic wave solutions of other nonlinear evolution equations.
文摘New exact solutions, expressed in terms of the Jacobi elliptic functions, to the nonlinear Klein-Gordon equation are obtained by using a modified mapping method. The solutions include the conditions for equation's parameters and travelling wave transformation parameters. Some figures for a specific kind of solution are also presented.
基金Project supported by the Anhui Key Laboratory of Information Materials and Devices (Anhui University),China
文摘In this paper, we make use of the auxiliary equation and the expanded mapping methods to find the new exact periodic solutions for (2+1)-dimensional dispersive long wave equations in mathematical physics, which are expressed by Jacobi elliptic functions, and obtain some new solitary wave solutions (m → 1). This method can also be used to explore new periodic wave solutions for other nonlinear evolution equations.