A new reliability-based multidisciplinary design optimization (RBMDO) framework is proposed by combining the single-loop-based reliability analysis (SLBRA) method with multidisciplinary feasible (MDF) method. Th...A new reliability-based multidisciplinary design optimization (RBMDO) framework is proposed by combining the single-loop-based reliability analysis (SLBRA) method with multidisciplinary feasible (MDF) method. The Kriging approximate model with updating is introduced to reduce the computational cost of MDF caused by the complex structure. The computational efficiency is remarkably improved as the lack of iterative process during reliability analysis. Special attention is paid to a turbine blade design optimization by adopting the proposed method. Results show that the method is much more efficient than the commonly used double-loop based RBMDO method. It is feasible and efficient to apply the method to the engineering design.展开更多
This paper deals with a type of servicing machines model, which service station has a life time of the kth Er-langian distribution and can be repaired just like a new one. The cyclic time and the inefficiency quantiti...This paper deals with a type of servicing machines model, which service station has a life time of the kth Er-langian distribution and can be repaired just like a new one. The cyclic time and the inefficiency quantities of this system in equilibrium are obtained.展开更多
A new 3M-dimensional Lie algebra X is constructed firstly. Then, the corresponding loop algebra X is produced, whose commutation operation defined by us is as simple and straightforward as that in the loop algebra A1....A new 3M-dimensional Lie algebra X is constructed firstly. Then, the corresponding loop algebra X is produced, whose commutation operation defined by us is as simple and straightforward as that in the loop algebra A1.It follows that a generalscheme for generating multi-component integrable hierarchy is proposed. By taking advantage of X, a new isospectral problem is established, and then well-known multi-component TC hierarchy is obtained. Finally,an expanding loop algebra FM of the loop algebra X is presented. Based on the FM, the multi-component integrable coupling system of the generalized multi-component TC hierarchy has been worked out. The method in this paper can be applied to other nonlinear evolution equations hierarchies. It is easy to find that we can construct any finite-dimensional Lie algebra by this approach.展开更多
A type of new loop algebra GM is constructed by making use of the concept of cycled numbers. As its application, an isospectral problem is designed and a new multi-component integrable hierarchy with multi-potential f...A type of new loop algebra GM is constructed by making use of the concept of cycled numbers. As its application, an isospectral problem is designed and a new multi-component integrable hierarchy with multi-potential functions is worked out, which can be reduced to the famous KN hierarchy.展开更多
A new matrix Lie algebra and its corresponding Loop algebra are constructed firstly,as its application,the multi-component TC equation hierarchy is obtained,then by use of trace identity the Hamiltonian structure of t...A new matrix Lie algebra and its corresponding Loop algebra are constructed firstly,as its application,the multi-component TC equation hierarchy is obtained,then by use of trace identity the Hamiltonian structure of the above system is presented.Finally,the integrable couplings of the obtained system is worked out by the expanding matrix Loop algebra.展开更多
Developing low-carbon economy and enhancing carbon productivity are basic approaches to coordinating economic development and protecting global environment, which are also the major ways to address climate change unde...Developing low-carbon economy and enhancing carbon productivity are basic approaches to coordinating economic development and protecting global environment, which are also the major ways to address climate change under the framework of sustainable development. In this paper, the authors analyze the annual rate of carbon productivity growth, the differences of carbon productivity of different countries, and the factors for enhancing carbon productivity. Consequently, the authors clarify their viewpoint that the annual rate of carbon productivity growth can be used to weigh the efforts that a country takes to address climate change, and propose policies and suggestions on promoting carbon production.展开更多
A simple 3M-dimensional loop algebra X is produced, whose commutation operation defined by us is A1 as simple and straightforward as that in the loop algebra A1. It follows that a general scheme for generating multi-...A simple 3M-dimensional loop algebra X is produced, whose commutation operation defined by us is A1 as simple and straightforward as that in the loop algebra A1. It follows that a general scheme for generating multi-component integrable hierarchy is proposed. By taking advantage of X, a new isospectral problem is established, and then by making use of the Tu scheme the well-known multi-component Levi hierarchy is obtained. Finally, an expanding loop algebra FM of the loop algebra .X is presented, based on the FM, the multi-component integrable coupling system of the multi-component Levi hierarchy is worked out. The method in this paper can be applied to other nonlinear evolution equation hierarchies.展开更多
This study aimed to explore the effect of 5% tembotrione oil dispersion(OD)-38% atrazine suspension concentrate(SC) tank mixture on the weeds in spring maize fields and the safety of the mixture. To be specific, rando...This study aimed to explore the effect of 5% tembotrione oil dispersion(OD)-38% atrazine suspension concentrate(SC) tank mixture on the weeds in spring maize fields and the safety of the mixture. To be specific, randomized block design was adopted for the field experiments. The results showed that the application of tankmixture of 5% tembotrione OD at 90 g a.i./hm^(2)and 38% atrazine SC at 570 g a.i./hm^(2)and the mixture of 5% tembotrione OD at 90 g a.i./hm^(2)and 38% atrazine SC at 1140 g a.i./hm^(2)respectively controlled 94.7%~96.3% and 94.0%~96.3% of the grass weeds, 94.7%~96.0% and 93.7%~95.7% fresh weight of grass weeds, 95.3%~96.3%and 93.3%~97.3% of broadleaf weeds, and 94.7%~96.0% and 93.3%~96.3% fresh weight of broadleaf weeds. The efficacy was better than that of the 5% tembotrione alone and the control herbicide and no phytotoxicity of the mixtures was identified.The tank mixture of tembotrione and atrazine should be promoted in the spring maize field for weed control and the recommended dosages were 90 g a.i./hm^(2)for 5%tembotrione and 570 g a.i./hm^(2)for 38% atrazine.展开更多
Educational achievement and age correlatives may have significant bearings on generation, maintenance, and sustenance of environment to disseminate education for comprehensive development of learners as permeation of ...Educational achievement and age correlatives may have significant bearings on generation, maintenance, and sustenance of environment to disseminate education for comprehensive development of learners as permeation of learning and its diffusion rate may vary depending upon different achievements on literacy scale for different age groups. More so, for disable learners as such learners need additional initiatives and assisting environment of even more literate fellow beings constituting surroundings. From this perspective, this paper makes a descriptive analytical effort to present census (2011) results in evaluating overall literacy position and that for disable ones alongwith environment availability through simple statistical tools展开更多
Based on the nonlinear continuum damage model (CDM) developed by Chaboehe, a modified model for high cycle fatigue of TC4 alloy was proposed. Unsymmetrical cycle fatigue tests were conducted on rod specimens at room...Based on the nonlinear continuum damage model (CDM) developed by Chaboehe, a modified model for high cycle fatigue of TC4 alloy was proposed. Unsymmetrical cycle fatigue tests were conducted on rod specimens at room temperature. Then the material parameters needed in the CDM were obtained by the fatigue tests, and the stress distribution of the specimen was calculated by FE method. Compared with the linear damage model (LDM), the dam- age results and the life prediction of the CDM show a better agreement with the test and they are more precise than the LDM. By applying the CDM developed in this study to the life prediction of aeroengine blades, it is concluded that the root is the most dangerous region of the whole blade and the shortest life is 58 211 cycles. Finally, the Cox propor- tional hazard model of survival analysis was applied to the analysis of the fatigue reliability. The Cox model takes the covariates into consideration, which include diameter, weight, mean stress and tensile strength. The result shows that the mean stress is the only factor that accelerates the fracture process.展开更多
In this paper, we give the conception of implicit congruence and nonimplicit congruence in a unique factorization domain R and establish some structures of irreducible polynomials over R . A classical result, E...In this paper, we give the conception of implicit congruence and nonimplicit congruence in a unique factorization domain R and establish some structures of irreducible polynomials over R . A classical result, Eisenstein′s criterion, is generalized.展开更多
This Paper gives a method to construct indecomposable positive definite integral Hermitianforman imnginary quadratic field Q with gin discriminant and g。n rank.It is shown that for ally natural numbers n and a, there...This Paper gives a method to construct indecomposable positive definite integral Hermitianforman imnginary quadratic field Q with gin discriminant and g。n rank.It is shown that for ally natural numbers n and a, there are n-ary Indecomposable positivedefinite intopal Herlllltian lattices over Q(resp. Q)with discriminant a, exceptfor four(resp. one) exceptions. In these exceptional cases there are no lattices with the desiredproperties.展开更多
This paper is concerned with limit cycles which bifurcate from a period annulus of a quadratic reversible Lotka-Volterra system with sextic orbits.The authors apply the property of an extended complete Chebyshev syste...This paper is concerned with limit cycles which bifurcate from a period annulus of a quadratic reversible Lotka-Volterra system with sextic orbits.The authors apply the property of an extended complete Chebyshev system and prove that the cyclicity of the period annulus under quadratic perturbations is equal to two.展开更多
A tunable metamaterial filter is designed based on split-ring resonators(SRRs) in this paper. The metamaterial filter has a compact size of 15 mm×20 mm, and miniaturization is realized by using the SRRs. By loadi...A tunable metamaterial filter is designed based on split-ring resonators(SRRs) in this paper. The metamaterial filter has a compact size of 15 mm×20 mm, and miniaturization is realized by using the SRRs. By loading tunable devices, the continuous operation of the filter is realized at X band(from 10.7 GHz to 12 GHz), the bandwidth is about 13%, the minimum return loss is 35 dB, and the maximum insertion loss is 0.37 d B. The results illustrate that the metamaterial filter shows the compact size, wide bandwidth and good band pass characteristics.展开更多
基金Supported by the National High Technology Research and Development Program of China("863" Program) (2009AA04Z418, 2007AA04Z404)the National "111" Project(B07050)~~
文摘A new reliability-based multidisciplinary design optimization (RBMDO) framework is proposed by combining the single-loop-based reliability analysis (SLBRA) method with multidisciplinary feasible (MDF) method. The Kriging approximate model with updating is introduced to reduce the computational cost of MDF caused by the complex structure. The computational efficiency is remarkably improved as the lack of iterative process during reliability analysis. Special attention is paid to a turbine blade design optimization by adopting the proposed method. Results show that the method is much more efficient than the commonly used double-loop based RBMDO method. It is feasible and efficient to apply the method to the engineering design.
文摘This paper deals with a type of servicing machines model, which service station has a life time of the kth Er-langian distribution and can be repaired just like a new one. The cyclic time and the inefficiency quantities of this system in equilibrium are obtained.
基金中国科学院资助项目,the Science Foundation of Liuhui Center of Tianjin University and Nankai University,辽宁省自然科学基金
文摘A new 3M-dimensional Lie algebra X is constructed firstly. Then, the corresponding loop algebra X is produced, whose commutation operation defined by us is as simple and straightforward as that in the loop algebra A1.It follows that a generalscheme for generating multi-component integrable hierarchy is proposed. By taking advantage of X, a new isospectral problem is established, and then well-known multi-component TC hierarchy is obtained. Finally,an expanding loop algebra FM of the loop algebra X is presented. Based on the FM, the multi-component integrable coupling system of the generalized multi-component TC hierarchy has been worked out. The method in this paper can be applied to other nonlinear evolution equations hierarchies. It is easy to find that we can construct any finite-dimensional Lie algebra by this approach.
基金The project supported by National Natural Science Foundation of China under.Grant No. 10371070
文摘A type of new loop algebra GM is constructed by making use of the concept of cycled numbers. As its application, an isospectral problem is designed and a new multi-component integrable hierarchy with multi-potential functions is worked out, which can be reduced to the famous KN hierarchy.
基金supported by Science Foundation of the Educational Department of Shandong Province of China
文摘A new matrix Lie algebra and its corresponding Loop algebra are constructed firstly,as its application,the multi-component TC equation hierarchy is obtained,then by use of trace identity the Hamiltonian structure of the above system is presented.Finally,the integrable couplings of the obtained system is worked out by the expanding matrix Loop algebra.
基金Major Project of Key Research Bases of Humanities and Social Sciences of Ministry of Education(05JJD630035)Major International Joint Research Program Founded by National Natural Science Foundation of China(50246003)Major Project(90410016)
文摘Developing low-carbon economy and enhancing carbon productivity are basic approaches to coordinating economic development and protecting global environment, which are also the major ways to address climate change under the framework of sustainable development. In this paper, the authors analyze the annual rate of carbon productivity growth, the differences of carbon productivity of different countries, and the factors for enhancing carbon productivity. Consequently, the authors clarify their viewpoint that the annual rate of carbon productivity growth can be used to weigh the efforts that a country takes to address climate change, and propose policies and suggestions on promoting carbon production.
基金the National Natural Science Foundation of China under,南开大学-天津大学合作项目,天津大学校科研和教改项目,the Educational Committee of Liaoning Province of China under Gant
文摘A simple 3M-dimensional loop algebra X is produced, whose commutation operation defined by us is A1 as simple and straightforward as that in the loop algebra A1. It follows that a general scheme for generating multi-component integrable hierarchy is proposed. By taking advantage of X, a new isospectral problem is established, and then by making use of the Tu scheme the well-known multi-component Levi hierarchy is obtained. Finally, an expanding loop algebra FM of the loop algebra .X is presented, based on the FM, the multi-component integrable coupling system of the multi-component Levi hierarchy is worked out. The method in this paper can be applied to other nonlinear evolution equation hierarchies.
文摘This study aimed to explore the effect of 5% tembotrione oil dispersion(OD)-38% atrazine suspension concentrate(SC) tank mixture on the weeds in spring maize fields and the safety of the mixture. To be specific, randomized block design was adopted for the field experiments. The results showed that the application of tankmixture of 5% tembotrione OD at 90 g a.i./hm^(2)and 38% atrazine SC at 570 g a.i./hm^(2)and the mixture of 5% tembotrione OD at 90 g a.i./hm^(2)and 38% atrazine SC at 1140 g a.i./hm^(2)respectively controlled 94.7%~96.3% and 94.0%~96.3% of the grass weeds, 94.7%~96.0% and 93.7%~95.7% fresh weight of grass weeds, 95.3%~96.3%and 93.3%~97.3% of broadleaf weeds, and 94.7%~96.0% and 93.3%~96.3% fresh weight of broadleaf weeds. The efficacy was better than that of the 5% tembotrione alone and the control herbicide and no phytotoxicity of the mixtures was identified.The tank mixture of tembotrione and atrazine should be promoted in the spring maize field for weed control and the recommended dosages were 90 g a.i./hm^(2)for 5%tembotrione and 570 g a.i./hm^(2)for 38% atrazine.
文摘Educational achievement and age correlatives may have significant bearings on generation, maintenance, and sustenance of environment to disseminate education for comprehensive development of learners as permeation of learning and its diffusion rate may vary depending upon different achievements on literacy scale for different age groups. More so, for disable learners as such learners need additional initiatives and assisting environment of even more literate fellow beings constituting surroundings. From this perspective, this paper makes a descriptive analytical effort to present census (2011) results in evaluating overall literacy position and that for disable ones alongwith environment availability through simple statistical tools
基金Supported by National Natural Science Foundation of China(No.60879002)Key Technologies R and D Program of Tianjin (No.10ZCKFGX03800)
文摘Based on the nonlinear continuum damage model (CDM) developed by Chaboehe, a modified model for high cycle fatigue of TC4 alloy was proposed. Unsymmetrical cycle fatigue tests were conducted on rod specimens at room temperature. Then the material parameters needed in the CDM were obtained by the fatigue tests, and the stress distribution of the specimen was calculated by FE method. Compared with the linear damage model (LDM), the dam- age results and the life prediction of the CDM show a better agreement with the test and they are more precise than the LDM. By applying the CDM developed in this study to the life prediction of aeroengine blades, it is concluded that the root is the most dangerous region of the whole blade and the shortest life is 58 211 cycles. Finally, the Cox propor- tional hazard model of survival analysis was applied to the analysis of the fatigue reliability. The Cox model takes the covariates into consideration, which include diameter, weight, mean stress and tensile strength. The result shows that the mean stress is the only factor that accelerates the fracture process.
文摘In this paper, we give the conception of implicit congruence and nonimplicit congruence in a unique factorization domain R and establish some structures of irreducible polynomials over R . A classical result, Eisenstein′s criterion, is generalized.
文摘This Paper gives a method to construct indecomposable positive definite integral Hermitianforman imnginary quadratic field Q with gin discriminant and g。n rank.It is shown that for ally natural numbers n and a, there are n-ary Indecomposable positivedefinite intopal Herlllltian lattices over Q(resp. Q)with discriminant a, exceptfor four(resp. one) exceptions. In these exceptional cases there are no lattices with the desiredproperties.
基金Project supported by the National Natural Science Foundation of China(Nos.11226152,11201086)the Science and Technology Foundation of Guizhou Province(No.[2012]2167)+1 种基金the Foundation for Distinguished Young Talents in Higher Education of Guangdong(No.2012LYM_0087)the Talent Project Foundation of Guizhou University(No.201104)
文摘This paper is concerned with limit cycles which bifurcate from a period annulus of a quadratic reversible Lotka-Volterra system with sextic orbits.The authors apply the property of an extended complete Chebyshev system and prove that the cyclicity of the period annulus under quadratic perturbations is equal to two.
基金supported by the Key Laboratory Foundation of China Electronics Technology Group Corporation(No.ZX15ZS391)the National Fund for International Cooperation in Science and Technology(No.2014DFR10020)the Natural Science Foundation of Shanxi Province(Nos.2014021020-1 and 2015021083)
文摘A tunable metamaterial filter is designed based on split-ring resonators(SRRs) in this paper. The metamaterial filter has a compact size of 15 mm×20 mm, and miniaturization is realized by using the SRRs. By loading tunable devices, the continuous operation of the filter is realized at X band(from 10.7 GHz to 12 GHz), the bandwidth is about 13%, the minimum return loss is 35 dB, and the maximum insertion loss is 0.37 d B. The results illustrate that the metamaterial filter shows the compact size, wide bandwidth and good band pass characteristics.