为了改善高压直流系统的故障后的恢复性能,在研究低压限流单元(voltage dependent current order limiter,VDCOL)对直流系统无功功率消耗和电压稳定性影响的基础上,提出了一种分段变速率低压限流单元(piecewise-variable-rate VDCOL,PVR...为了改善高压直流系统的故障后的恢复性能,在研究低压限流单元(voltage dependent current order limiter,VDCOL)对直流系统无功功率消耗和电压稳定性影响的基础上,提出了一种分段变速率低压限流单元(piecewise-variable-rate VDCOL,PVR-VDCOL)的控制方法,该方法通过将电压下降或恢复过程划分为几个不同的阶段,并在每个阶段根据电压水平的不同而设置不同的功率恢复速率。推导了控制器初值的计算公式,制定了利用Simplex算法优化控制器参数的流程,并重点分析了分段数目对控制器性能的影响及其确定方法。在PSCAD/EMTDC中对提出的PVR-VDCOL和传统线性VDCOL的控制效果进行了对比仿真,并对不同分段数目下的仿真结果进行了对比分析,仿真结果表明提出的PVR-VDCOL能够有效改善直流系统的恢复性能。展开更多
The mid-facet of a simplex in n-dimensional Euclidean space which was introduced quite recently is an important geometric element. An analytic expression for the mid-facet area of a simplex is firstly given. In order ...The mid-facet of a simplex in n-dimensional Euclidean space which was introduced quite recently is an important geometric element. An analytic expression for the mid-facet area of a simplex is firstly given. In order to obtain the expression,the exterior differential method was presented. Furthermore, the properties of the mid-facets of a simplex analogous to median lines of a triangle (such as for all mid-facets of a simplex,there exists another simplex such that its edge-lengths equal to these mid-facets area respectively, and all of the mid-facets of a simplex have a common point) were proved. Finally, by applying the analytic expression, a number of inequalities which combine edge-lengths, circumradius, median line, bisection area and facet area with the mid-facet area for a simplex were established.展开更多
A simplex particle swarm optimization(simplex-PSO) derived from the Nelder-Mead simplex method was proposed to optimize the high dimensionality functions.In simplex-PSO,the velocity term was abandoned and its referenc...A simplex particle swarm optimization(simplex-PSO) derived from the Nelder-Mead simplex method was proposed to optimize the high dimensionality functions.In simplex-PSO,the velocity term was abandoned and its reference objectives were the best particle and the centroid of all particles except the best particle.The convergence theorems of linear time-varying discrete system proved that simplex-PSO is of consistent asymptotic convergence.In order to reduce the probability of trapping into a local optimal value,an extremum mutation was introduced into simplex-PSO and simplex-PSO-t(simplex-PSO with turbulence) was devised.Several experiments were carried out to verify the validity of simplex-PSO and simplex-PSO-t,and the experimental results confirmed the conclusions:(1) simplex-PSO-t can optimize high-dimension functions with 200-dimensionality;(2) compared PSO with chaos PSO(CPSO),the best optimum index increases by a factor of 1×102-1×104.展开更多
A global convergent algorithm is proposed to solve bilevel linear fractional-linear programming, which is a special class of bilevel programming. In our algorithm, replacing the lower level problem by its dual gap equ...A global convergent algorithm is proposed to solve bilevel linear fractional-linear programming, which is a special class of bilevel programming. In our algorithm, replacing the lower level problem by its dual gap equaling to zero, the bilevel linear fractional-linear programming is transformed into a traditional sin- gle level programming problem, which can be transformed into a series of linear fractional programming problem. Thus, the modi- fied convex simplex method is used to solve the infinite linear fractional programming to obtain the global convergent solution of the original bilevel linear fractional-linear programming. Finally, an example demonstrates the feasibility of the proposed algorithm.展开更多
For physical ozone absorption without reaction,two parametric estimation methods,i.e.the common linear least square fitting and non-linear Simplex search methods,were applied,respectively,to determine the ozone mass t...For physical ozone absorption without reaction,two parametric estimation methods,i.e.the common linear least square fitting and non-linear Simplex search methods,were applied,respectively,to determine the ozone mass transfer coefficient during absorption and both methods give almost the same mass transfer coefficient.While for chemical absorption with ozone decomposition reaction,the common linear least square fitting method is not applicable for the evaluation of ozone mass transfer coefficient due to the difficulty of model linearization for describing ozone concentration dissolved in water.The nonlinear Simplex method obtains the mass transfer coefficient by minimizing the sum of the differences between the simulated and experimental ozone concentration during the whole absorption process,without the limitation of linear relationship between the dissolved ozone concentration and absorption time during the initial stage of absorption.Comparison of the ozone concentration profiles between the simulation and experimental data demonstrates that Simplex method may determine ozone mass transfer coefficient during absorption in an accurate and high efficiency way with wide applicability.展开更多
OBJECTIVE How infection of Herpes simplex virus typeⅠ(HSV-1) induces enhancement of autophagy.MEHTODS The wild type HSV-1 strain Kos 1.1 was propagated in Vero cells and purified.SK-N-SH cells seeded in DMEM/F12 were...OBJECTIVE How infection of Herpes simplex virus typeⅠ(HSV-1) induces enhancement of autophagy.MEHTODS The wild type HSV-1 strain Kos 1.1 was propagated in Vero cells and purified.SK-N-SH cells seeded in DMEM/F12 were exposed to HSV-1 with 6 h or 12 h and multiplicity of infection(MOI) for 10 or 40 in each experiment.The infectious titers of the HSV-1 samples were determined by plaque assays.MDC staining to test the number of autophagosome within the cell after infection with time and moi was indicated in each experiment.At the molecular level,Western blotting and immunofluorescence analyses were done to study the expression of the proteins related to the cell autophagy.The mRNA transcribed from the gene related to autophagy was quantified by reverse transcription followed by real-time PCR.After intranasal infection of different transgenic mice,immunoflurorence studies were done to detected the expression of Aβ42 and proteins related to autophagy from the brain sections.Morris water maze experiment was performed to test the change of spatial learning and memory between different transgenic mice.RESULTS SK-N-SH cell showed time-and moi-dependent increase of MDC positive staining after HSV-1 infection.Western blotting analysis showed that LC3-Ⅱ was less in mock-infected cells but it was detected after 12 h from 10 to 40 moi HSV-1 infected cells.The level increased in a viral concentration-dependent manner.In agreement with the Western blotting results,direct fluorescence microscopy revealed that the signals of LC3 were consistent with their localization on autophagic compartments.P62,another protein related to autophagoysome formation,also increased with MOI.15 ku fragment of intracellular apolipoproteins E(APOE) protein increased after infection,but at the mRNA level it remained the same.The expression of APP showed less decrease but intracellular Aβ42 increased significantly compared with the mock group.Within the brain,after intranasal infection for 7 d,autophagy related proteins LC3 b and P62 increased as well,at the same time Aβ42 was found co-localized with LC3 b within the cell.Behavior test revealed that 17-month-old APOE4 mice had pool spatial learning and memory after infection compared with other groups.CONCLUSION HSV-1 induces an autophagic response and accelerates the fragmentation of APOE protein.展开更多
In this paper, a hybrid simplex-improved genetic algorithm (HSIGA) which combines simplex method (SM) and genetic algorithm (GA) is proposed to solve global numerical optimization problems. In this hybrid algorithm so...In this paper, a hybrid simplex-improved genetic algorithm (HSIGA) which combines simplex method (SM) and genetic algorithm (GA) is proposed to solve global numerical optimization problems. In this hybrid algorithm some improved genetic mechanisms, for example, non-linear ranking selection, competition and selection among several crossover offspring, adaptive change of mutation scaling and stage evolution, are adopted; and new population is produced through three ap-proaches, i.e. elitist strategy, modified simplex strategy and improved genetic algorithm (IGA) strategy. Numerical experi-ments are included to demonstrate effectiveness of the proposed algorithm.展开更多
文摘为了改善高压直流系统的故障后的恢复性能,在研究低压限流单元(voltage dependent current order limiter,VDCOL)对直流系统无功功率消耗和电压稳定性影响的基础上,提出了一种分段变速率低压限流单元(piecewise-variable-rate VDCOL,PVR-VDCOL)的控制方法,该方法通过将电压下降或恢复过程划分为几个不同的阶段,并在每个阶段根据电压水平的不同而设置不同的功率恢复速率。推导了控制器初值的计算公式,制定了利用Simplex算法优化控制器参数的流程,并重点分析了分段数目对控制器性能的影响及其确定方法。在PSCAD/EMTDC中对提出的PVR-VDCOL和传统线性VDCOL的控制效果进行了对比仿真,并对不同分段数目下的仿真结果进行了对比分析,仿真结果表明提出的PVR-VDCOL能够有效改善直流系统的恢复性能。
文摘The mid-facet of a simplex in n-dimensional Euclidean space which was introduced quite recently is an important geometric element. An analytic expression for the mid-facet area of a simplex is firstly given. In order to obtain the expression,the exterior differential method was presented. Furthermore, the properties of the mid-facets of a simplex analogous to median lines of a triangle (such as for all mid-facets of a simplex,there exists another simplex such that its edge-lengths equal to these mid-facets area respectively, and all of the mid-facets of a simplex have a common point) were proved. Finally, by applying the analytic expression, a number of inequalities which combine edge-lengths, circumradius, median line, bisection area and facet area with the mid-facet area for a simplex were established.
基金Project(50275150) supported by the National Natural Science Foundation of ChinaProject(20070533131) supported by Research Fund for the Doctoral Program of Higher Education of China
文摘A simplex particle swarm optimization(simplex-PSO) derived from the Nelder-Mead simplex method was proposed to optimize the high dimensionality functions.In simplex-PSO,the velocity term was abandoned and its reference objectives were the best particle and the centroid of all particles except the best particle.The convergence theorems of linear time-varying discrete system proved that simplex-PSO is of consistent asymptotic convergence.In order to reduce the probability of trapping into a local optimal value,an extremum mutation was introduced into simplex-PSO and simplex-PSO-t(simplex-PSO with turbulence) was devised.Several experiments were carried out to verify the validity of simplex-PSO and simplex-PSO-t,and the experimental results confirmed the conclusions:(1) simplex-PSO-t can optimize high-dimension functions with 200-dimensionality;(2) compared PSO with chaos PSO(CPSO),the best optimum index increases by a factor of 1×102-1×104.
基金supported by the National Natural Science Foundation of China(70771080)the Special Fund for Basic Scientific Research of Central Colleges+2 种基金China University of Geosciences(Wuhan) (CUG090113)the Research Foundation for Outstanding Young TeachersChina University of Geosciences(Wuhan)(CUGQNW0801)
文摘A global convergent algorithm is proposed to solve bilevel linear fractional-linear programming, which is a special class of bilevel programming. In our algorithm, replacing the lower level problem by its dual gap equaling to zero, the bilevel linear fractional-linear programming is transformed into a traditional sin- gle level programming problem, which can be transformed into a series of linear fractional programming problem. Thus, the modi- fied convex simplex method is used to solve the infinite linear fractional programming to obtain the global convergent solution of the original bilevel linear fractional-linear programming. Finally, an example demonstrates the feasibility of the proposed algorithm.
基金Project(2011467001)supported by the Ministry of Environment Protection of ChinaProject(2010DFB94130)supported by the Ministry of Science and Technology of China
文摘For physical ozone absorption without reaction,two parametric estimation methods,i.e.the common linear least square fitting and non-linear Simplex search methods,were applied,respectively,to determine the ozone mass transfer coefficient during absorption and both methods give almost the same mass transfer coefficient.While for chemical absorption with ozone decomposition reaction,the common linear least square fitting method is not applicable for the evaluation of ozone mass transfer coefficient due to the difficulty of model linearization for describing ozone concentration dissolved in water.The nonlinear Simplex method obtains the mass transfer coefficient by minimizing the sum of the differences between the simulated and experimental ozone concentration during the whole absorption process,without the limitation of linear relationship between the dissolved ozone concentration and absorption time during the initial stage of absorption.Comparison of the ozone concentration profiles between the simulation and experimental data demonstrates that Simplex method may determine ozone mass transfer coefficient during absorption in an accurate and high efficiency way with wide applicability.
基金National Natural Science Fundation of China (81471232).
文摘OBJECTIVE How infection of Herpes simplex virus typeⅠ(HSV-1) induces enhancement of autophagy.MEHTODS The wild type HSV-1 strain Kos 1.1 was propagated in Vero cells and purified.SK-N-SH cells seeded in DMEM/F12 were exposed to HSV-1 with 6 h or 12 h and multiplicity of infection(MOI) for 10 or 40 in each experiment.The infectious titers of the HSV-1 samples were determined by plaque assays.MDC staining to test the number of autophagosome within the cell after infection with time and moi was indicated in each experiment.At the molecular level,Western blotting and immunofluorescence analyses were done to study the expression of the proteins related to the cell autophagy.The mRNA transcribed from the gene related to autophagy was quantified by reverse transcription followed by real-time PCR.After intranasal infection of different transgenic mice,immunoflurorence studies were done to detected the expression of Aβ42 and proteins related to autophagy from the brain sections.Morris water maze experiment was performed to test the change of spatial learning and memory between different transgenic mice.RESULTS SK-N-SH cell showed time-and moi-dependent increase of MDC positive staining after HSV-1 infection.Western blotting analysis showed that LC3-Ⅱ was less in mock-infected cells but it was detected after 12 h from 10 to 40 moi HSV-1 infected cells.The level increased in a viral concentration-dependent manner.In agreement with the Western blotting results,direct fluorescence microscopy revealed that the signals of LC3 were consistent with their localization on autophagic compartments.P62,another protein related to autophagoysome formation,also increased with MOI.15 ku fragment of intracellular apolipoproteins E(APOE) protein increased after infection,but at the mRNA level it remained the same.The expression of APP showed less decrease but intracellular Aβ42 increased significantly compared with the mock group.Within the brain,after intranasal infection for 7 d,autophagy related proteins LC3 b and P62 increased as well,at the same time Aβ42 was found co-localized with LC3 b within the cell.Behavior test revealed that 17-month-old APOE4 mice had pool spatial learning and memory after infection compared with other groups.CONCLUSION HSV-1 induces an autophagic response and accelerates the fragmentation of APOE protein.
基金Supported by National Natural Science Foundation of P.R.China(60474069)
文摘In this paper, a hybrid simplex-improved genetic algorithm (HSIGA) which combines simplex method (SM) and genetic algorithm (GA) is proposed to solve global numerical optimization problems. In this hybrid algorithm some improved genetic mechanisms, for example, non-linear ranking selection, competition and selection among several crossover offspring, adaptive change of mutation scaling and stage evolution, are adopted; and new population is produced through three ap-proaches, i.e. elitist strategy, modified simplex strategy and improved genetic algorithm (IGA) strategy. Numerical experi-ments are included to demonstrate effectiveness of the proposed algorithm.
