In order to solve the springback problem in sheet metal forming, the trial and error method is a widely used method in the factory, which is time-consuming and costly for its non-direction and non-quantitative. Finite...In order to solve the springback problem in sheet metal forming, the trial and error method is a widely used method in the factory, which is time-consuming and costly for its non-direction and non-quantitative. Finite element simulation is an e ective method to predict the springback of complex shape parts, but its precision is sensitive to the simulation model, particularly material model and boundary conditions. In this paper, the simple iterative method is introduced to establish the iterative compensation algorithm, and the convergence criterion of iterative parameters is put forward. In addition, the new algorithm is applied to the V-free bending and stretch-bending processes, and the convergence of curvature and bending angle is proved theoretically and verified experimentally. At the same time,the iterative compensation experiments for plane bending show that, the new method can predict the next compensaantido tnh ev atlaureg ebta cseurdv oatnu trhe ew sitphri tnhgeb earcrko ro fo fe laecshs ttehsat,n s0 o. 5 th%a ta rteh eo btatraigneet db aefntedri n2 g-3 a nitgelrea tiwoitnhs.t Thhei se rrreosre aorf clhe sps rtohpaons e±s 0 a.1%new iterative compensation algorithm to predict springback in sheet metal forming process, where each compensation value depends only on the iteration parameter di erence before and after springback for the same forming process of same material.展开更多
Platform planning is one of the important problems in the command and control(C2) field. Hereto, we analyze the platform planning problem and present nonlinear optimal model aiming at maximizing the task completion qu...Platform planning is one of the important problems in the command and control(C2) field. Hereto, we analyze the platform planning problem and present nonlinear optimal model aiming at maximizing the task completion qualities. Firstly, we take into account the relation among tasks and build the single task nonlinear optimal model with a set of platform constraints. The Lagrange relaxation method and the pruning strategy are used to solve the model. Secondly, this paper presents optimization-based planning algorithms for efficiently allocating platforms to multiple tasks. To achieve the balance of the resource assignments among tasks, the m-best assignment algorithm and the pair-wise exchange(PWE)method are used to maximize multiple tasks completion qualities.Finally, a series of experiments are designed to verify the superiority and effectiveness of the proposed model and algorithms.展开更多
Chlorophyll fluorescence,particularly the parameter F_(v)/F_(m),has emerged as a reliable,non-invasive indicator of the maximum quantum efficiency of Photosystem II(PSII)in plants.Over the past decade,significant rese...Chlorophyll fluorescence,particularly the parameter F_(v)/F_(m),has emerged as a reliable,non-invasive indicator of the maximum quantum efficiency of Photosystem II(PSII)in plants.Over the past decade,significant research has leveraged F_(v)/F_(m) to evaluate plant responses to a wide range of biotic and abiotic stresses,as well as to support crop improvement and ecological monitoring.This review synthesizes recent progress in understanding the physiological basis,measurement techniques,and applied significance of F_(v)/F_(m) across diverse plant systems.We highlight methodological advancements in fluorescence imaging and remote sensing,identify consistent patterns and contrasting findings in stress-response studies,and explore how F_(v)/F_(m) correlates with other physiological and molecular indicators.Despite its widespread use,challenges remain regarding data interpretation,environmental variability,and integration with multi-parameter models.This review also addresses critical knowledge gaps and proposes future research directions,including AI-driven analysis,a least-squares support vector machine(LSSVM)model,and high-resolution phenotyping.By consolidating findings from recent literature,this work provides a comprehensive reference for researchers aiming to harness F_(v)/F_(m) in both basic and applied plant sciences.展开更多
The H9N2 subtype avian influenza virus(AIV)continues to propagate and undergo evolution within China,thereby posing a significant threat to the poultry industry.This study encompassed the collection of 436 samples and...The H9N2 subtype avian influenza virus(AIV)continues to propagate and undergo evolution within China,thereby posing a significant threat to the poultry industry.This study encompassed the collection of 436 samples and swabs in East China over the period spanning 2018 to 2019,from which 31 strains of the H9N2 subtype viruses were isolated and purified.We revealed that the HA and NA genes of the 31 isolates categorized within the Y280 branch,while the PB2 and M genes were associated with the G1 branch,and the remaining genes aligned with the F/98 branch.Despite this alignment,antigenic mapping demonstrated differences between the 2018 and 2019 strains,with the early vaccine strains displaying low serological reactivity toward these isolates.Notably,the CK/SH/49/19 isolate exhibited lethality in mice,characterized by a PB2 E627V mutation and a HA deletion at amino acid position 217.Mechanistically,in vitro studies showed that the influenza virus CK/SH/49/19 carrying PB2627V and HA 217M mutations displayed enhanced replication capacity,attributed to the heightened activity of the polymerase with PB2627V.Moreover,the absence of the amino acid at the HA 217 site obstructed viral adsorption and internalization,resulted in lower activation pH,and impeded the virus budding process.Critically,in vivo experiments revealed that CK/SH/49/19(PB2627V,HA 217Δ)triggered a robust activation of interferon response and interferon-stimulated genes.This study furnished a theoretical foundation for the scientific prevention and control strategies against H9N2 subtype avian influenza.展开更多
Nonlinear m-term approximation plays an important role in machine learning, signal processing and statistical estimating. In this paper by means of a nondecreasing dominated function, a greedy adaptive compression num...Nonlinear m-term approximation plays an important role in machine learning, signal processing and statistical estimating. In this paper by means of a nondecreasing dominated function, a greedy adaptive compression numerical algorithm in the best m -term approximation with regard to tensor product wavelet-type basis is pro-posed. The algorithm provides the asymptotically optimal approximation for the class of periodic functions with mixed Besov smoothness in the L q norm. Moreover, it depends only on the expansion of function f by tensor pro-duct wavelet-type basis, but neither on q nor on any special features of f.展开更多
In this paper, a new class of over-relaxed proximal point algorithms for solving nonlinear operator equations with (A,η,m)-monotonicity framework in Hilbert spaces is introduced and studied. Further, by using the gen...In this paper, a new class of over-relaxed proximal point algorithms for solving nonlinear operator equations with (A,η,m)-monotonicity framework in Hilbert spaces is introduced and studied. Further, by using the generalized resolvent operator technique associated with the (A,η,m)-monotone operators, the approximation solvability of the operator equation problems and the convergence of iterative sequences generated by the algorithm are discussed. Our results improve and generalize the corresponding results in the literature.展开更多
A Leverrier-like algorithm is presented which allows the computation of the transfer function of a linear regular system from its m-D state-space description,without inverting a multivariable polynomial matrix. This a...A Leverrier-like algorithm is presented which allows the computation of the transfer function of a linear regular system from its m-D state-space description,without inverting a multivariable polynomial matrix. This algorithm is an extension of the classic Leverrier's algorithm for 1-D system and it reduces the computational cost.ra-D Cayley-Hamilton theorem is also shown by the algorithm.展开更多
We consider the inverse problem of finding cavities within some object from electrostatic measurements on the boundary. By a cavity we understand any object with a different electrical conductivity from the background...We consider the inverse problem of finding cavities within some object from electrostatic measurements on the boundary. By a cavity we understand any object with a different electrical conductivity from the background material of the body. We give an algorithm for solving this inverse problem based on the output nonlinear least-square formulation and the regularized Newton-type iteration. In particular, we present a number of numerical results to highlight the potential and the limitations of this method.展开更多
Let A be m by n matrix, M and N be positive definite matrices of order in and n respectively. This paper presents an efficient method for computing (M-N) singular value decomposition((M-N) SVD) of A on a cube connecte...Let A be m by n matrix, M and N be positive definite matrices of order in and n respectively. This paper presents an efficient method for computing (M-N) singular value decomposition((M-N) SVD) of A on a cube connected single instruction stream-multiple data stream(SIMD) parallel computer. This method is based on a one-sided orthogonalization algorithm due to Hestenes. On the cube connected SIMD parallel computer with o(n) processors, the (M -- N) SVD of a matrix A requires a computation time of o(m3 log m/n).展开更多
An adaptive MIMO detection algorithm for LTE-A system which is based on sphere detection is proposed in this paper. The proposed algorithm uses M-algorithm for reference to remove unreliable constellation candidates b...An adaptive MIMO detection algorithm for LTE-A system which is based on sphere detection is proposed in this paper. The proposed algorithm uses M-algorithm for reference to remove unreliable constellation candidates before search, and the number of constellation reservation is adaptively adjusted according to SNR. Simulations of LTE-A downlink show that the BER performance of the proposed detection algorithm is nearly the same as maximum likelihood (ML) detection algorithm. However, the complexity is reduced by about 30% compared with full constellation sphere detection.展开更多
根据支持向量机(SVM)的计算理论,结合高光谱影像的数据特点,利用最近点算法(NPA)求两类最优超平面,为每类设立一个合理的权指标,提出了基于NPA的加权"1 V m"SVM算法来实现高光谱遥感影像多分类,降低了计算的复杂度和计算量,...根据支持向量机(SVM)的计算理论,结合高光谱影像的数据特点,利用最近点算法(NPA)求两类最优超平面,为每类设立一个合理的权指标,提出了基于NPA的加权"1 V m"SVM算法来实现高光谱遥感影像多分类,降低了计算的复杂度和计算量,提高了SVM高光谱遥感影像分类的可操作性和分类效率。展开更多
基金Supported by Hebei Provincial Natural Science Foundation of in China(Grant Nos.E2015203244,E2016203266)Program for the Youth Top-notch Talents of Hebei Province
文摘In order to solve the springback problem in sheet metal forming, the trial and error method is a widely used method in the factory, which is time-consuming and costly for its non-direction and non-quantitative. Finite element simulation is an e ective method to predict the springback of complex shape parts, but its precision is sensitive to the simulation model, particularly material model and boundary conditions. In this paper, the simple iterative method is introduced to establish the iterative compensation algorithm, and the convergence criterion of iterative parameters is put forward. In addition, the new algorithm is applied to the V-free bending and stretch-bending processes, and the convergence of curvature and bending angle is proved theoretically and verified experimentally. At the same time,the iterative compensation experiments for plane bending show that, the new method can predict the next compensaantido tnh ev atlaureg ebta cseurdv oatnu trhe ew sitphri tnhgeb earcrko ro fo fe laecshs ttehsat,n s0 o. 5 th%a ta rteh eo btatraigneet db aefntedri n2 g-3 a nitgelrea tiwoitnhs.t Thhei se rrreosre aorf clhe sps rtohpaons e±s 0 a.1%new iterative compensation algorithm to predict springback in sheet metal forming process, where each compensation value depends only on the iteration parameter di erence before and after springback for the same forming process of same material.
基金supported by the National Natural Science Foundation of China(61573017 61703425)+2 种基金the Aeronautical Science Fund(20175796014)the Shaanxi Province Natural Science Foundation Research Project(2016JQ6062 2017JM6062)
文摘Platform planning is one of the important problems in the command and control(C2) field. Hereto, we analyze the platform planning problem and present nonlinear optimal model aiming at maximizing the task completion qualities. Firstly, we take into account the relation among tasks and build the single task nonlinear optimal model with a set of platform constraints. The Lagrange relaxation method and the pruning strategy are used to solve the model. Secondly, this paper presents optimization-based planning algorithms for efficiently allocating platforms to multiple tasks. To achieve the balance of the resource assignments among tasks, the m-best assignment algorithm and the pair-wise exchange(PWE)method are used to maximize multiple tasks completion qualities.Finally, a series of experiments are designed to verify the superiority and effectiveness of the proposed model and algorithms.
基金supported by the National Natural Science Foundation of China(32000197,32200429).
文摘Chlorophyll fluorescence,particularly the parameter F_(v)/F_(m),has emerged as a reliable,non-invasive indicator of the maximum quantum efficiency of Photosystem II(PSII)in plants.Over the past decade,significant research has leveraged F_(v)/F_(m) to evaluate plant responses to a wide range of biotic and abiotic stresses,as well as to support crop improvement and ecological monitoring.This review synthesizes recent progress in understanding the physiological basis,measurement techniques,and applied significance of F_(v)/F_(m) across diverse plant systems.We highlight methodological advancements in fluorescence imaging and remote sensing,identify consistent patterns and contrasting findings in stress-response studies,and explore how F_(v)/F_(m) correlates with other physiological and molecular indicators.Despite its widespread use,challenges remain regarding data interpretation,environmental variability,and integration with multi-parameter models.This review also addresses critical knowledge gaps and proposes future research directions,including AI-driven analysis,a least-squares support vector machine(LSSVM)model,and high-resolution phenotyping.By consolidating findings from recent literature,this work provides a comprehensive reference for researchers aiming to harness F_(v)/F_(m) in both basic and applied plant sciences.
基金supported by National Natural Science Foundation of China[Grant number:32272992(JP),31772775(JP)]National Key Research and Development Program of China[Grant number:2021YFD1800205(JP)].
文摘The H9N2 subtype avian influenza virus(AIV)continues to propagate and undergo evolution within China,thereby posing a significant threat to the poultry industry.This study encompassed the collection of 436 samples and swabs in East China over the period spanning 2018 to 2019,from which 31 strains of the H9N2 subtype viruses were isolated and purified.We revealed that the HA and NA genes of the 31 isolates categorized within the Y280 branch,while the PB2 and M genes were associated with the G1 branch,and the remaining genes aligned with the F/98 branch.Despite this alignment,antigenic mapping demonstrated differences between the 2018 and 2019 strains,with the early vaccine strains displaying low serological reactivity toward these isolates.Notably,the CK/SH/49/19 isolate exhibited lethality in mice,characterized by a PB2 E627V mutation and a HA deletion at amino acid position 217.Mechanistically,in vitro studies showed that the influenza virus CK/SH/49/19 carrying PB2627V and HA 217M mutations displayed enhanced replication capacity,attributed to the heightened activity of the polymerase with PB2627V.Moreover,the absence of the amino acid at the HA 217 site obstructed viral adsorption and internalization,resulted in lower activation pH,and impeded the virus budding process.Critically,in vivo experiments revealed that CK/SH/49/19(PB2627V,HA 217Δ)triggered a robust activation of interferon response and interferon-stimulated genes.This study furnished a theoretical foundation for the scientific prevention and control strategies against H9N2 subtype avian influenza.
基金Supported by National Natural Science Foundation of China (No. 60872161, 10501026, 60675010 and 10626029)Natural Science Foundation of Tianjin (No. 08JCYBJC09600)China Postdoctoral Science Foundation ( No. 20070420708).
文摘Nonlinear m-term approximation plays an important role in machine learning, signal processing and statistical estimating. In this paper by means of a nondecreasing dominated function, a greedy adaptive compression numerical algorithm in the best m -term approximation with regard to tensor product wavelet-type basis is pro-posed. The algorithm provides the asymptotically optimal approximation for the class of periodic functions with mixed Besov smoothness in the L q norm. Moreover, it depends only on the expansion of function f by tensor pro-duct wavelet-type basis, but neither on q nor on any special features of f.
文摘In this paper, a new class of over-relaxed proximal point algorithms for solving nonlinear operator equations with (A,η,m)-monotonicity framework in Hilbert spaces is introduced and studied. Further, by using the generalized resolvent operator technique associated with the (A,η,m)-monotone operators, the approximation solvability of the operator equation problems and the convergence of iterative sequences generated by the algorithm are discussed. Our results improve and generalize the corresponding results in the literature.
基金Supported by NSFC Project 19971057, Science and Technology Foundation of Shanhai Higher Eduction Project 03DZ04, and The Special Funds for Major Specialities of Shanghai Eduction Committee. Partly supported by Chinese Scholarship Council.
文摘A Leverrier-like algorithm is presented which allows the computation of the transfer function of a linear regular system from its m-D state-space description,without inverting a multivariable polynomial matrix. This algorithm is an extension of the classic Leverrier's algorithm for 1-D system and it reduces the computational cost.ra-D Cayley-Hamilton theorem is also shown by the algorithm.
文摘We consider the inverse problem of finding cavities within some object from electrostatic measurements on the boundary. By a cavity we understand any object with a different electrical conductivity from the background material of the body. We give an algorithm for solving this inverse problem based on the output nonlinear least-square formulation and the regularized Newton-type iteration. In particular, we present a number of numerical results to highlight the potential and the limitations of this method.
文摘Let A be m by n matrix, M and N be positive definite matrices of order in and n respectively. This paper presents an efficient method for computing (M-N) singular value decomposition((M-N) SVD) of A on a cube connected single instruction stream-multiple data stream(SIMD) parallel computer. This method is based on a one-sided orthogonalization algorithm due to Hestenes. On the cube connected SIMD parallel computer with o(n) processors, the (M -- N) SVD of a matrix A requires a computation time of o(m3 log m/n).
文摘An adaptive MIMO detection algorithm for LTE-A system which is based on sphere detection is proposed in this paper. The proposed algorithm uses M-algorithm for reference to remove unreliable constellation candidates before search, and the number of constellation reservation is adaptively adjusted according to SNR. Simulations of LTE-A downlink show that the BER performance of the proposed detection algorithm is nearly the same as maximum likelihood (ML) detection algorithm. However, the complexity is reduced by about 30% compared with full constellation sphere detection.
