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Discrete Approximation and Convergence Analysis for a Class of Decision-Dependent Two-Stage Stochastic Linear Programs

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Journal of the Operations Research Society of China 2024年第3期12卷 649-679页

作者： Jie Jiang zhi-ping chen College of Mathematics and Statistics Chongqing UniversityChongqing401331China School of Mathematics and Statistics Xi’an Jiaotong UniversityXi’an710049ShaanxiChina Center for Optimization Technique and Quantitative Finance Xi’an International Academy for Mathematics and Mathematical TechnologyXi’an710049ShaanxiChina

Customary stochastic programming with recourse assumes that the probability distribution of random parameters is independent of decision *** studies demonstrated that stochastic programming models with endogenous uncertainty can better reflect many real-world activities and applications accompanying with decision-dependent *** this paper,we concentrate on a class of decision-dependent two-stage stochastic programs(DTSPs)and investigate their discrete *** develop the discrete approximation methods for DTSPs,we first derive the quantitative stability results for *** on the stability conclusion,we examine two discretization schemes when the support set of random variables is bounded,and give the rates of convergence for the optimal value and optimal solution set of the discrete approximation problem to those of the original *** we extend the proposed approaches to the general situation with an unbounded support set by using the truncating *** an illustration of our discretization schemes,we reformulate the discretization problems under specific structures of the decision-dependent ***,an application and numerical results are presented to demonstrate our theoretical results.

关键词： Stochastic programming Decision-dependence Discrete approximation Stability Convergence rate

Development on test equipment of coal slurry mixing tank

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第3期11卷 175-180页

作者： Jin WANG Xu-wen ZHANG zhi-ping chen Jian-hua LAN Institute of Process Equipment Zhejiang UniversityHangzhou 310027China Shanghai Research Institute of Chemical Industry Shanghai 200062China

A coal slurry mixing tank is a key piece of equipment in the preparation of coal slurry for direct coal *** is a gas-liquid-solid three-phase mixing *** on the performance of the existing coal slurry mixing equipment,a type of test equipment for horizontal continuous coal slurry preparation was developed,but to this point has limited research *** test equipment consists of a mixing cylinder,mixer,stirring impeller and other *** mixing experiments were undertaken using the prototype,testing the performance of the device.A mathematical model was proposed specifically for the operation of a coal slurry mixing tank that is horizontally operated with high slurry concentration and rotary *** flow field in the horizontal coal mixing tank was simulated with the computational fluid dynamic (CFD) *** experimental results match well with the CFD simulation *** show that the test device of a coal slurry mixing tank can be used to model the mixing of pulverized coal and the solvent oil.A strong correlation was obtained.

关键词： Gas-liquid-solid mixing Mixing equipment Experimental research Numerical simulation Direct liquefaction

Time Consistent Multi-period Worst-Case Risk Measure in Robust Portfolio Selection

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Journal of the Operations Research Society of China 2018年第1期6卷 139-158页

作者： aJia Liu zhi-ping chen Yong-Chang Hui Department of Computing Science School of Mathematics and StatisticsXi’an Jiaotong UniversityXi’an 710049China

In this paper,we first construct a time consistent multi-period worst-case risk measure,which measures the dynamic investment risk period-wise from a distributionally robust *** the usually adopted uncertainty set,we derive the explicit optimal investment strategy for the multi-period robust portfolio selection problem under the multi-period worst-case risk *** results demonstrate that the portfolio selection model under the proposed risk measure is a good complement to existing multi-period robust portfolio selection models using the adjustable robust approach.

关键词： Distributionally robust optimization Multi-period risk measure Dynamic portfolio selection Conditional value-at-risk

Effect of weld reinforcement on axial plastic buckling of welded steel cylindrical shells

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第2期13卷 79-90页

作者： Chu-lin YU zhi-ping chen Ji WANG Shun-juan YAN Li-cai YANG Institute of Process Equipment Zhejiang UniversityHangzhou 310027China

The effect of weld reinforcement on axial plastic buckling of welded steel cylindrical shells is investigated through experimental and numerical buckling analysis using six welded steel cylindrical shell specimens. The relationship between the amplitude of weld reinforcement and the axial plastic buckling critical load is explored. The effect of the material yield strength and the number of circumferential welds on the axial plastic buckling is studied. Results show that circumferential weld reinforcement represents a severe imperfect form of axially compressed welded steel cylindrical shells and the axial plastic buckling critical load decreases with the increment of the mean amplitude of circumferential weld reinforcement. The material yield strength and the number of circumferential welds are found to have no significant effect on buckling waveforms; however, the axial plastic buckling critical load can be decreased to some extent with the increase of the number of circumferential welds.

关键词： Cylindrical shells Axial buckling Plastic Weld Reinforcement Geometric imperfections

Data-driven Stochastic Programming with Distributionally Robust Constraints Under Wasserstein Distance:Asymptotic Properties

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Journal of the Operations Research Society of China 2021年第3期9卷 525-542页

作者： Yu Mei zhi-ping chen Bing-Bing Ji Zhu-Jia Xu Jia Liu Department of Computing Science School of Mathematics and StatisticsXi’an Jiaotong UniversityXi’an 710049China Center for Optimization Technique and Quantitative Finance Xi’an International Academy for Mathematics and Mathematical TechnologyXi’an 710049China

Distributionally robust optimization is a dominant paradigm for decision-making problems where the distribution of random variables is *** investigate a distributionally robust optimization problem with ambiguities in the objective function and countably infinite *** ambiguity set is defined as a Wasserstein ball centered at the empirical *** on the concentration inequality of Wasserstein distance,we establish the asymptotic convergence property of the datadriven distributionally robust optimization problem when the sample size goes to *** show that with probability 1,the optimal value and the optimal solution set of the data-driven distributionally robust problem converge to those of the stochastic optimization problem with true ***,we provide numerical evidences for the established theoretical results.

关键词： Distributionally robust optimization Wasserstein distance Ambiguity set Asymptotic analysis Empirical distribution

A Scheme for Generating Cluster States via Raman Interaction

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Communications in Theoretical Physics 2007年第1期47卷 53-58页

作者： YANG Rong-Can LI Hong-Cai LIN Xiu HUANG zhi-ping chen Mei-Xiang School of Physics and Optoelectronics Technology Fujian Normal University Fuzhou 350007 China

A scheme for generating cluster states via Raman interaction is proposed. In the scheme, we firstly prepare cluster states of multi-cavities with information encoded in the coherent states and then generate cluster states of multiatoms, which encode the information in the ground states of A-type atoms. The advantages of our scheme are that the atomic spontaneous radiation can be efficiently reduced since the cavity frequency is largely detuned from the atomic transition frequency and the Hadamard gate operation of the coherent states is replaced by measuring the coherent states.

关键词： cluster states Raman interaction A-type three-level atom coherent states

Inhibiting Apoptosis of CTLL-2 Cells to Enhance Their GVL Effects via Anti-Fas Ribozyme

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Acta Biochimica et Biophysica Sinica 2004年第8期36卷 559-565页

作者： Min ZHANG, Fang LIU, Lin-Bo LIU, Yong YOU, zhi-Chao chen, and ping ZOUInstitute of Hematology, Union Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan 430022, China Institute of Hematology Union Hospital Tongji Medical College Huazhong University of Science & TechnologyWuhan 430022 China

To investigate the inhibition role of anti-Fas hammerhead ribozyme on fas expression and Fas-mediated apoptosis of CTL cell line CTLL-2 cells, the cDNA of an anti-Fas hammerhead ribozyme was synthesized, its expression plasmid was constructed and transfected into CTLL-2 cells by electroporation. fas expression of CTLL-2 cells was detected by RT-PCR and Western blot. CTLL-2 cell viability was measured using MTT assay when co-cultured with mouse T cell leukemia cell line EL4 cells that highly expressed Fas ligand (FasL). Meanwhile, caspase-3 proteolytic activity was detected, and cell apoptosis was measured by flow cytometry and Hochest-PI double staining. Killing activity of CTLL-2 cells was detected by lactate dehydrogenase (LDH) releasing assay in vitro. Results showed that the expression of both Fas mRNA and protein in CTLL-2 cells were decreased after transfection of anti-Fas ribozyme. Compared with mock- transfected group and mutant ribozyme-transfected group, viability of CTLL-2 cells co-cultured with EL4 cells was increased significantly and cells killing activity was enhanced after transfected with anti-Fas ribozyme, while the caspase-3 activity and apoptosis rate was significantly decreased. The results demonstrated anti-Fas ribozyme could efficiently cleave Fas and inhibit Fas-mediated apoptosis of CTLL-2 cells to improve their viability. Our study made a basis for enhancing CTLL-2 cells anti-leukemia effect in DLI.

关键词： Hammerhead ribozyme anti-Fas CTLL-2 cells apoptosis tumor immunity

Sensitivity to Estimation Errors in Mean-variance Models

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Acta Mathematicae Applicatae Sinica 2003年第2期19卷 255-266页

作者： zhi-ping chen, Cai-e ZhaoDepartment of Scientific Computing and Applied Softwares, Faculty of Science, Xi’an Jiaotong University, Xi’an 710049, China Department of Scientific Computing and Applied Softwares Faculty of Science Xi'an Jiaotong University Xi'an China

Abstract In order to give a complex and accurate description about the sensitivity of efficient portfolios to changes in asset's expected returns, variances and covariances, the joint effect of estimation errors in means, variances and covariances on the efficient portfolio's weights is investigated in this paper. It is proved that the efficient portfolio's composition is a Lipschitz continuous, differentiable mapping of these parameters under suitable conditions. The change rate of the efficient portfolio's weights with respect to variations about risk-return estimations is derived by estimating the Lipschitz constant. Our general quantitative results show that the efficient portfolio's weights are normally not so sensitive to estimation errors about means and variances. Moreover, we point out those extreme cases which might cause stability problems and how to avoid them in practice. Preliminary numerical results are also provided as an illustration to our theoretical results.

关键词： Keywords The MV model estimation error sensitivity Lipschitz continuity

“One stone, two birds”: Salt template enabling porosity engineering and single metal atom coordinating toward high-performance zinc-ion capacitors

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Journal of Energy Chemistry 2025年第1期100卷 637-645页

作者： Chunliu Zhu Huanyu Liang ping Li chenglong Qiu Jingyi Wu Jingwei chen Weiqian Tian Yue Zhu zhi Li Huanlei Wang School of Materials Science and Engineering Ocean University of China Department of Chemical and Materials Engineering University of Alberta

Zinc-ion hybrid capacitors （ZIHCs） have received increasing attention as energy storage devices owing to their low cost,high safety,and environmental ***,their progress has been hampered by low energy and power density,as well as unsatisfactory long-cycle stability,mainly due to the lack of suitable electrode *** this context,we have developed manganese single atoms implanted in nitrogen-doped porous carbon nanosheets （MnSAs/NCNs） using a metal salt template method as cathodes for *** metal salt serves a dual purpose in the synthesis process:It facilitates the uniform dispersion of Mn atoms within the carbon matrix and acts as an activating agent to create the porous *** applied in ZIHCs,the MnSAs/NCNs electrode demonstrates exceptional performance,including a high capacity of 203 m Ah g-1,an energy density of 138 Wh kg-1at 68 W kg-1,and excellent cycle stability with 91%retention over 10,000 *** calculations indicate that the introduced Mn atoms modulate the local charge distribution of carbon materials,thereby improving the electrochemical *** work demonstrates the significant potential of carbon materials with metal atoms in zinc-ion hybrid capacitors,not only in enhancing electrochemical performance but also in providing new insights and methods for developing high-performance energy storage devices.

关键词： Zinc ion hybrid capacitors Cathodes Carbon materials Heteroatoms Single atoms