Process of optimizing coordinated control is divided into two stages. At the first stage, the study improves a robust optimal control model of single-point intersection to optimize cycle and split. At the second stage...Process of optimizing coordinated control is divided into two stages. At the first stage, the study improves a robust optimal control model of single-point intersection to optimize cycle and split. At the second stage, the study combines all links with intersections of arterial road as a complete system, and applies cell transmission model to simulate traffic flow on urban signalized arterial road. We propose a coordinated control model based on the platform to optimize offset between adjacent intersections. Genetic algorithm is executed by MATLAB to solve the model. The performance evaluations show that the model not only effectively reduces average delay and stopping rate of vehicles on arterial road and largely enhances traffic capacity of arterial road, but also lowers the sensitivity of signal control for flow fluctuations.展开更多
Recently, iteratively reweighted methods have attracted much interest in compressed sensing, outperforming their unweighted counterparts in most cases. In these methods, decision variables and weights are optimized al...Recently, iteratively reweighted methods have attracted much interest in compressed sensing, outperforming their unweighted counterparts in most cases. In these methods, decision variables and weights are optimized alternatingly, or decision variables are optimized under heuristically chosen weights. In this paper,we present a novel weighted l1-norm minimization problem for the sparsest solution of underdetermined linear equations. We propose an iteratively weighted thresholding method for this problem, wherein decision variables and weights are optimized simultaneously. Furthermore, we prove that the iteration process will converge eventually. Using the homotopy technique, we enhance the performance of the iteratively weighted thresholding method. Finally, extensive computational experiments show that our method performs better in terms of both running time and recovery accuracy compared with some state-of-the-art methods.展开更多
Given an undirected graph with edge weights,the max-cut problem is to find a partition of the vertices into twosubsets,such that the sumof theweights of the edges crossing different subsets ismaximized.Heuristics base...Given an undirected graph with edge weights,the max-cut problem is to find a partition of the vertices into twosubsets,such that the sumof theweights of the edges crossing different subsets ismaximized.Heuristics based on auxiliary function can obtain high-quality solutions of the max-cut problem,but suffer high solution cost when instances grow large.In this paper,we combine clustered adaptive multistart and discrete dynamic convexized method to obtain high-quality solutions in a reasonable time.Computational experiments on two sets of benchmark instances from the literature were performed.Numerical results and comparisons with some heuristics based on auxiliary function show that the proposed algorithm is much faster and can obtain better solutions.Comparisons with several state-ofthe-science heuristics demonstrate that the proposed algorithm is competitive.展开更多
Based on the range space property (RSP), the equivalent conditions between nonnegative solutions to the partial sparse and the corresponding weighted l1-norm minimization problem are studied in this paper. Different...Based on the range space property (RSP), the equivalent conditions between nonnegative solutions to the partial sparse and the corresponding weighted l1-norm minimization problem are studied in this paper. Different from other conditions based on the spark property, the mutual coherence, the null space property (NSP) and the restricted isometry property (RIP), the RSP- based conditions are easier to be verified. Moreover, the proposed conditions guarantee not only the strong equivalence, but also the equivalence between the two problems. First, according to the foundation of the strict complemenrarity theorem of linear programming, a sufficient and necessary condition, satisfying the RSP of the sensing matrix and the full column rank property of the corresponding sub-matrix, is presented for the unique nonnegative solution to the weighted l1-norm minimization problem. Then, based on this condition, the equivalence conditions between the two problems are proposed. Finally, this paper shows that the matrix with the RSP of order k can guarantee the strong equivalence of the two problems.展开更多
Detailed routing has become much challenging in modern circuit designs due to the extreme scaling of chip size and the complicated design rules.In this paper,we give an effective algorithm for detailed routing conside...Detailed routing has become much challenging in modern circuit designs due to the extreme scaling of chip size and the complicated design rules.In this paper,we give an effective algorithm for detailed routing considering advanced technology nodes.First,we present a valid pin-access candidates generation technology for handling complex pin shapes.Then,we propose a tree-based nets components selection algorithm to decide connecting order for multiple nets components.Finally,combined with global routing results and advanced technology nodes,an initial routing results optimization algorithm is presented to achieve the final detailed routing results.Experimental results on industry benchmarks show that,our proposed algorithm not only achieves 100%routability on real industrial cases in a reasonable runtime,but also optimizes total wirelength,total vias and other advanced technology nodes simultaneously.展开更多
基金supported by the National Natural Science Foundation of China(No.61174175)the Science & Technology Development Plan of Shandong Province(No.2011GGX10504)+4 种基金the Science Foundation of Shandong Jiaotong University(No.Z201111)the Natural Science Foundation of Shandong Province(No.ZR2009GM032)the Independent Innovation Foundation of Shandong University(No.2009TS046)the Natural Science Foundation of Shandong Province(No.ZR2010FM036)the Science & Technology Projects of Higher Education of Shangdong Province(No. J09LG55)
文摘Process of optimizing coordinated control is divided into two stages. At the first stage, the study improves a robust optimal control model of single-point intersection to optimize cycle and split. At the second stage, the study combines all links with intersections of arterial road as a complete system, and applies cell transmission model to simulate traffic flow on urban signalized arterial road. We propose a coordinated control model based on the platform to optimize offset between adjacent intersections. Genetic algorithm is executed by MATLAB to solve the model. The performance evaluations show that the model not only effectively reduces average delay and stopping rate of vehicles on arterial road and largely enhances traffic capacity of arterial road, but also lowers the sensitivity of signal control for flow fluctuations.
基金supported by National Natural Science Foundation of China(Grant Nos.61672005 and 11571074)。
文摘Recently, iteratively reweighted methods have attracted much interest in compressed sensing, outperforming their unweighted counterparts in most cases. In these methods, decision variables and weights are optimized alternatingly, or decision variables are optimized under heuristically chosen weights. In this paper,we present a novel weighted l1-norm minimization problem for the sparsest solution of underdetermined linear equations. We propose an iteratively weighted thresholding method for this problem, wherein decision variables and weights are optimized simultaneously. Furthermore, we prove that the iteration process will converge eventually. Using the homotopy technique, we enhance the performance of the iteratively weighted thresholding method. Finally, extensive computational experiments show that our method performs better in terms of both running time and recovery accuracy compared with some state-of-the-art methods.
基金supported partially by the National Natural Science Foundation of China(Nos.11226236 and 11301255)the Natural Science Foundation of Fujian Province of China(No.2012J05007)the Science and Technology Project of the Education Bureau of Fujian,China(Nos.JA13246 and JK2012037).
文摘Given an undirected graph with edge weights,the max-cut problem is to find a partition of the vertices into twosubsets,such that the sumof theweights of the edges crossing different subsets ismaximized.Heuristics based on auxiliary function can obtain high-quality solutions of the max-cut problem,but suffer high solution cost when instances grow large.In this paper,we combine clustered adaptive multistart and discrete dynamic convexized method to obtain high-quality solutions in a reasonable time.Computational experiments on two sets of benchmark instances from the literature were performed.Numerical results and comparisons with some heuristics based on auxiliary function show that the proposed algorithm is much faster and can obtain better solutions.Comparisons with several state-ofthe-science heuristics demonstrate that the proposed algorithm is competitive.
基金Research supported by the National Natural Science Foundation of China under Grant 61672005
文摘Based on the range space property (RSP), the equivalent conditions between nonnegative solutions to the partial sparse and the corresponding weighted l1-norm minimization problem are studied in this paper. Different from other conditions based on the spark property, the mutual coherence, the null space property (NSP) and the restricted isometry property (RIP), the RSP- based conditions are easier to be verified. Moreover, the proposed conditions guarantee not only the strong equivalence, but also the equivalence between the two problems. First, according to the foundation of the strict complemenrarity theorem of linear programming, a sufficient and necessary condition, satisfying the RSP of the sensing matrix and the full column rank property of the corresponding sub-matrix, is presented for the unique nonnegative solution to the weighted l1-norm minimization problem. Then, based on this condition, the equivalence conditions between the two problems are proposed. Finally, this paper shows that the matrix with the RSP of order k can guarantee the strong equivalence of the two problems.
文摘Detailed routing has become much challenging in modern circuit designs due to the extreme scaling of chip size and the complicated design rules.In this paper,we give an effective algorithm for detailed routing considering advanced technology nodes.First,we present a valid pin-access candidates generation technology for handling complex pin shapes.Then,we propose a tree-based nets components selection algorithm to decide connecting order for multiple nets components.Finally,combined with global routing results and advanced technology nodes,an initial routing results optimization algorithm is presented to achieve the final detailed routing results.Experimental results on industry benchmarks show that,our proposed algorithm not only achieves 100%routability on real industrial cases in a reasonable runtime,but also optimizes total wirelength,total vias and other advanced technology nodes simultaneously.