检索结果-南通市图书馆

Optimal Risk Sharing for Maxmin Choquet Expected Utility Model

在线全文

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2024年第2期40卷 430-444页

作者： de-jian tian Shang-ri WU School of Mathematics China University of Mining and TechnologyXuzhou 221116China

This article analyzes the Pareto optimal allocations,agreeable trades and agreeable bets under the maxmin Choquet expected utility(MCEU)*** provide several useful characterizations for Pareto optimal allocations for risk averse *** derive the formulation descriptions for non-existence agreeable trades or agreeable bets for risk neutral *** build some relationships between ex-ante stage and interim stage on agreeable trades or bets when new information arrives.

关键词： maxmin Choquet expected utility model Pareto optimal allocation agreeable trade agreeable bet

Estimation of glacier ice storage in western China constrained by field ground-penetrating Radar surveys

在线全文

学校读者我要写书评

暂无评论

Advances in Climate Change Research 2022年第3期13卷 359-374页

作者： Peng-Bin LIANG Li-de tian Institute of International Rivers and Eco-Security Yunnan UniversityKunming 650500China Yunnan Key Laboratory of International Rivers and Transboundary Eco-security Kunming 650091China

Recent decades have witnessed the accelerated retreat of alpine glaciers,which likely portends a decline in the glacial ice melt on which large downstream populations rely for ***,estimating water storage in alpine glaciers is critical for predicting the trend of glacier *** study compiled a rich set of ice thickness observations for glaciers of varying sizes in western *** here presented a first-order assessment of the various errors involved in interpreting ice thickness from ground-penetrating radar(GPR)*** empirical Bayesian kriging(EBK)method was used for ice thickness interpolation and volume *** then established a new volume-scaling law specific to western China glaciers based on these 36 volume-area *** together with the Second Chinese Glacier Inventory(SCGI),we obtain a regional volume estimate of 4451±298 km^(3).By comparison,we believed that this result is the most reliable estimate of the total ice storage in western China and more reliably predicts gross glacier ***,our results show that the method of glacier division can strongly affect the total volume estimation,which previous studies *** emphasizes the need for more surveyed glaciers data and more accurate glacier inventory to improve the evaluation of the climate impact on glacier melting water resources and to help ensure the future survival of these alpine glaciers.

关键词： Ground-penetrating radar Glacier thickness survey Glacier volume volume-area scaling law Distributed model Western China

Ant colony optimization for assembly sequence planning based on parameters optimization

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Mechanical Engineering 2021年第2期16卷 393-409页

作者： Zunpu HAN Yong WANG de tian Renewable Energy School North China Electric Power UniversityBeijing 102206China College of Mechanical and Electronic Engineering Tarim UniversityAlar 843300China

As an important part of product design and manufacturing, assembly sequence planning (ASP) has a considerable impact on product quality and manufacturing costs. ASP is a typical NP-complete problem that requires effective methods to find the optimal or near-optimal assembly sequence. First, multiple assembly constraints and rules are incorporated into an assembly model. The assembly constraints and rules guarantee to obtain a reasonable assembly sequence. Second, an algorithm called SOS-ACO that combines symbiotic organisms search (SOS) and ant colony optimization (ACO) is proposed to calculate the optimal or near-optimal assembly sequence. Several of the ACO parameter values are given, and the remaining ones are adaptively optimized by SOS. Thus, the complexity of ACO parameter assignment is greatly reduced. Compared with the ACO algorithm, the hybrid SOS-ACO algorithm finds optimal or near-optimal assembly sequences in fewer iterations. SOS-ACO is also robust in identifying the best assembly sequence in nearly every experiment. Lastly, the performance of SOS-ACO when the given ACO parameters are changed is analyzed through experiments. Experimental results reveal that SOS-ACO has good adaptive capability to various values of given parameters and can achieve competitive solutions.

关键词： assembly sequence planning ant colony optimization symbiotic organisms search parameter optimization

The Coverage Holes of The Largest Component of Random Geometric Graph

在线全文

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2015年第4期31卷 855-862页

作者： Chang-long YAO tian-de GUO School of Mathematical Sciences Peking University School of Mathematical Sciences University of Chinese Academy of Sciences

In this paper, a domain in a cube is called a coverage hole if it is not covered by the largest component of the random geometric graph in this cube. We obtain asymptotic properties of the size of the largest coverage hole in the cube. In addition, we give an exponentially decaying tail bound for the probability that a line with length s do not intersect with the coverage of the infinite component of continuum percolation. These results have applications in communication networks and especially in wireless ad-hoc sensor networks.

关键词： random geometric graph continuum percolation wireless sensor networks, coverage

Flag-transitive point-primitive 2-(v,k,4) symmetric designs and two dimensional classical groups

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics(A Journal of Chinese Universities) 2011年第3期26卷 334-341页

作者： ZHOU Sheng-lin tian de-lu department of Mathematics South China University of Technology Guangzhou 510640 China

Let D be a 2-（v, k, 4） symmetric design and G be a flag-transitive point-primitive automorphism group of D with X ≥G ≤Aut（X） where X ≌ PSL2（q）.Then D is a 2-（15,8,4） symmetric design with X = PSL2（9） and ... 详细信息

关键词： Symmetric design flag-transitive point-primitive two dimensional classical group.

An Overview of Stochastic Quasi-Newton Methods for Large-Scale Machine Learning

在线全文

学校读者我要写书评

暂无评论

Journal of the Operations Research Society of China 2023年第2期11卷 245-275页

作者： tian-de Guo Yan Liu Cong-Ying Han School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 101408China School of Statistics and Data Science KLMDASRLEBPSand LPMCNankai UniversityTianjin 300071China

Numerous intriguing optimization problems arise as a result of the advancement of machine *** stochastic first-ordermethod is the predominant choicefor those problems due to its high ***,the negative effects of noisy gradient estimates and high nonlinearity of the loss function result in a slow convergence ***-order algorithms have their typical advantages in dealing with highly nonlinear and ill-conditioning *** paper provides a review on recent developments in stochastic variants of quasi-Newton methods,which construct the Hessian approximations using only gradient *** concentrate on BFGS-based methods in stochastic settings and highlight the algorithmic improvements that enable the algorithm to work in various *** research on stochastic quasi-Newton methods should focus on enhancing its applicability,lowering the computational and storage costs,and improving the convergence rate.

关键词： Stochastic quasi-Newton methods BFGS Large-scale machine learning

development of a New High-throughput Screening Model for Human High density Lipoprotein Receptor (CLA-1) Agonists

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 2005年第4期18卷 265-272页

作者： de-FENG tian BIN HONG SHU-YI SI Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100050 China

To develop a new high-throughput screening model for human high-density lipoprotein （HDL） receptor （CD36 and LIMPⅡ analogous-1, CLA-1） agonists using CLA-1-expressing insect cells. Methods With the total RNA of human hepatoma cells BEL-7402 as template, the complementary DNA （cDNA） of CLA-1 was amplified by reverse transcription-polymerase chain reaction （RT-PCR）. Bac-to-Bac baculovirus expression system was used to express CLA-1 in insect cells. CLA-1 cDNA was cloned downstream of polyhedrin promoter of Autographa californica nuclear polyhedrosis virus （AcNPV） into donor vector pFastBacl and recombinant pFastBacl-CLA-1 was transformed into E. coli DH10Bac to transpose CLA-1 cDNA to bacrnid DNA. Recombinant bacrnid-CLA-1 was transfected into Spodopterafrugiperda Sf9 insect cells to produce recombinant baculovirus particles. Recombinant CLA- 1 was expressed on the membrane of Sf9 cells infected with the recombinant baculoviruses. A series of parameters of DiI-lipoprotein binding assays of CLA-1-expressing Sf9 cells in 96-well plates were optimized. Results Western blot analysis and DiI-lipoprotein binding assays confirmed that CLA-1 expressed in insect cells had similar immunoreactivity and ligand binding activity as its native counterpart. A reliable and sensitive in vitro cell-based assay was established to assess the activity of CLA-1 and used to screen agonists from different sample libraries. Conclusion Human HDL receptor CLA-1 was successfully expressed in Sf9 insect cells and a novel high-throughput screening model for CLA-1 agonists was developed. Utilization of this model allows us to identify potent and selective CLA-1 agonists which might possibly be used as therapeutics for atherosclerosis.

关键词： HDL SR-BI CLA-1 Insect cells High-throughput screening model Agonist

Some Properties for the Largest Component of Random Geometric Graphs with Applications in Sensor Networks

在线全文

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2009年第4期25卷 579-592页

作者： Ge Chen tian-de Guo Chang-long Yao School of Mathematical Science Graduate University of Chinese Academy of Sciences Beijing 100049 China

In this paper we consider the standard Poisson Boolean model of random geometric graphs G（Hλ,s; 1） in Rd and study the properties of the order of the largest component L1 （G（Hλ,s; 1）） . We prove that ElL1 （G（Hλ,s; 1））] is smooth with respect to A, and is derivable with respect to s. Also, we give the expression of these derivatives. These studies provide some new methods for the theory of the largest component of finite random geometric graphs （not asymptotic graphs as s - co） in the high dimensional space （d 〉 2）. Moreover, we investigate the convergence rate of E[L1（G（Hλ,s; 1））]. These results have significance for theory development of random geometric graphs and its practical application. Using our theories, we construct and solve a new optimal energy-efficient topology control model of wireless sensor networks, which has the significance of theoretical foundation and guidance for the design of network layout.

关键词： Random geometric graph the largest component wireless sensor networks topology control

Convergence of Stochastic Gradient descent in deep Neural Network

在线全文

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2021年第1期37卷 126-136页

作者： Bai-cun ZHOU Cong-ying HAN tian-de GUO School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Big Data Mining and Knowledge Management Chinese Academy of SciencesBeijing 100190China

Stochastic gradient descent(SGD) is one of the most common optimization algorithms used in pattern recognition and machine *** algorithm and its variants are the preferred algorithm while optimizing parameters of deep neural network for their advantages of low storage space requirement and fast computation *** studies on convergence of these algorithms were based on some traditional assumptions in optimization ***,the deep neural network has its unique *** assumptions are inappropriate in the actual optimization process of this kind of *** this paper,we modify the assumptions to make them more consistent with the actual optimization process of deep neural *** on new assumptions,we studied the convergence and convergence rate of SGD and its two common variant *** addition,we carried out numerical experiments with LeNet-5,a common network framework,on the data set MNIST to verify the rationality of our assumptions.

关键词： stochastic gradient descent deep neural network convergence