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A Line Search SQP-type Method with Bi-object Strategy for Nonlinear Semidefinite Programming

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Acta Mathematicae Applicatae Sinica 2022年第2期38卷 388-409页

作者： wen-hao FU zhong-wen CHEN School of Mathematical Sciences Suzhou University of Science and TechnologySuzhou 215009China School of Mathematical Sciences Soochow UniversitySuzhou 215006China

We propose a line search exact penalty method with bi-object strategy for nonlinear semidefinite *** each iteration,we solve a linear semidefinite programming to test whether the linearized constraints are consistent or *** search direction is generated by a piecewise quadratic-linear model of the exact penalty *** penalty parameter is only related to the information of the current iterate *** line search strategy is a penalty-free *** and local convergence are analyzed under suitable *** finally report some numerical experiments to illustrate the behavior of the algorithm on various degeneracy situations.

关键词： nonlinear semidefinite programming bi-object strategy global convergence rate of convergence

Optimal Grading Policies in the Online Acquisition of Used Products

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Journal of Systems Science and Systems Engineering 2021年第1期30卷 29-43页

作者： Xiang Chu zhong wen Jian Chen School of Maritime Economics and Management Dalian Maritime UniversityDalian116026China International Business School Beijing Foreign Studies UniversityBeijing100089China School of Economics and Management Tsinghua UniversityBeijing100084China

Although online reverse commerce(recommerce)is convenient and efficient,it is not without *** limits recommerce firms’flexibility to offer personalized prices and may cause mismatched grading between the firms and sellers of used *** study examines a recommerce firm’s decision on grading criteria and *** find that the firm’s optimal policy exhibits two distinctly different patterns depending on the trade value of the *** demonstrate that sellers’overestimate and underestimate errors have qualitatively different effects on firm profitability,and the effects crucially rely on the type of optimal *** findings can apprise firms on how to preset sorting criteria and prices as well as reduce grading errors.

关键词： Closed-loop supply chains used-product acquisition management recommerce grading error grading policy

Coupling potential and viscous flow models with domain decomposition for wave propagations

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Journal of Hydrodynamics 2022年第5期34卷 826-848页

作者： wen-jie zhong wen-tao Wang De-cheng Wan Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China China Ship Scientific Research Center Wuxi214082China

Either potential flow or viscous flow based model may be flawed for numerical wave *** two-way coupling of potential and viscous flow models with the domain decomposition utilizing respective strengths has been a trending research *** contrast to existing literatures in which closed source potential models were used,the widely used open source OceanWave3D,OpenFOAM-v2012 are used in the present *** innovative overlapping two-way coupling strategy is developed utilizing the ghost points in *** guarantee computational stability,a relaxation zone used both for outlet damping and data transfer is built over the overlapping region in *** free surface elevation in the relaxation zone is directly probed in OpenFOAM while the velocity potential is indirectly built upon its temporal variation which is calculated by the free surface boundary condition using the probed *** coupling is achieved based on the fourth-order Runge-Kutta(RK)*** two-and three-dimensional tests including linear,nonlinear,irregular,and multi-directional irregular waves,are *** effectiveness of the coupling procedure in bidirectional data transfer is fully demonstrated,and the model is validated to be accurate and efficient,thus providing a competitive alternative for ocean wave simulations.

关键词： Domain decomposition numerical wave tank potential/viscous flow coupling irregular waves wave-structure interaction

Wideband angle of arrival estimation of chirp signals using virtual Wignerville distribution

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Journal of Systems Engineering and Electronics 2007年第2期18卷 243-248页

作者： wen zhong Li Liping Zhang Xixiang School of Electronic Engineering Univ. of Electronic Science and Technology of ChinaChengdu 610054 P. R. China

To estimate the angle of arrivals （AOA） of wideband chirp sources, a new timo-frequency algorithm is proposed. In this method, virtual sensors are constructed based on the fact that the steering vectors of wideband chirp signals are linear and vary with time. And the randon Wignersville distribution （RWVD） of real sensors and virtual sensors are calculated to yield the new time-invariable steering vectors, furthermore, the noise and cross terms are suppressed. In addition, the multiple chirp signals are selected by their time-frequency points. The cost of computation is lower than the common AOA estimation methods of wideband sources due to nonrequirement of frequency focusing, interpolating and matrix decomposition, including subspace decomposition. Under the lower signal noise ratio （SNR） condition, the proposed method exhibits better precision than the method of frequency focusing （FF）. The proposed method can be further applied to nonuniform linear array （NLA） since it is not confined to the array geometry. Simulation results illustrate the efficacy of the proposed method.

关键词： Array signal processing Angle of arrivals Wignerville distribution Wideband chirp signal.

Sensor data compression based on MapReduce

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The Journal of China Universities of Posts and Telecommunications 2014年第1期21卷 60-66页

作者： YU Yu GUO zhong-wen Department of Computer Science and Engineer Ocean University of China

A compression algorithm is proposed in this paper for reducing the size of sensor data. By using a dictionary-based lossless compression algorithm, sensor data can be compressed efficiently and interpreted without decompressing. The correlation between redundancy of sensor data and compression ratio is explored. Further, a parallel compression algorithm based on MapReduce [1] is proposed. Meanwhile, data partitioner which plays an important role in performance of MapReduce application is discussed along with performance evaluation criteria proposed in this paper. Experiments demonstrate that random sampler is suitable for highly redundant sensor data and the proposed compression algorithms can compress those highly redundant sensor data efficiently.

关键词： data compression sensor data MapReduce surveillance application measurement system

Model Selection in Estimation of Covariance Functions for Growth of Angora Goats

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Agricultural Sciences in China 2010年第7期9卷 1041-1049页

作者： LIU wen-zhong ZHANG Yuan ZHOU zhong-xiao College of Animal Science and Technology Shanxi Agricultural University Taigu 030801 P.R.China College of Animal Science and Technology China Agricultural University Beijing 100193 P.R.China

Covariance functions have been proposed as an alternative to model longitudinal data in animal breeding because of their various merits in comparison to the classical analytical *** practical estimation,different models and polynomial orders fitted can influence the estimates of covariance functions and thus genetic *** objective of this study was to select model for estimation of covariance functions for body weights of Angora goats at 7 time *** functions were estimated by fitting 6 random regression models with birth year,birth month,sex,age of dam,birth type,and relative birth date as fixed *** effects involved were direct and maternal additive genetic,and animal and maternal permanent environmental effects with different orders of *** of model and orders of fit were carried out by likelihood ratio test and 4 types of information *** results showed that model with 6 orders of polynomial fit for direct additive genetic and animal permanent environmental effects and 4 and 5 orders for maternal genetic and permanent environmental effects,respectively,were preferable for estimation of covariance *** with and without maternal effects influenced the estimates of covariance functions *** permanent environmental effect does not explain the variation of all permanent environments,well suggesting different sources of permanent environmental effects also has large influence on covariance function estimates.

关键词： Angora goats growth covariance function model selection random regression model

Optimal Technology Investment under Emission Trading Policy

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Journal of Systems Science and Systems Engineering 2020年第2期29卷 143-162页

作者： Shuo Huang zhong wen Jian Chen Ning Cui School of Economics and Management Tsinghua UniversityBeijing 100084China Beijing Foreign Studies University China Southern Asset Management Co. Ltd.

Low-carbon economy is gaining growing attention nowadays as global warming *** a market-based policy,emission trading policy is widely considered an effective means to achieve the doublewin of economic development and environmental *** such circumstances,carbon trading markets are developing rapidly in many countries and regions,demanding more attention to compliance strategy issues for emission-intensive *** this study,we build a dynamic programming model in search of the optimal emission trading and technology investment decisions for a make-to-order company faced with a stochastic demand under emission trading *** a comprehensive analysis of the proposed model,we find that an optimal emission permit level,which increases in carbon penalty and decreases in carbon price,exists in each *** for the abatement technology investment decision,the firm should invest only ff the investment cost per unit of abatement effort is less than a certain threshold,which increases in carbon penalty and carbon *** the basis of a two-period dynamic programming model,we further explore the problem of investment *** show how optimal investment decisions are influenced by the speed of technology progress under different *** findings are important for firms to choose the time of investment depending on specific situations.

关键词： Low-carbon emission trading compliance strategy investment-timing

Reliability Evaluation and Improvement of Islanded Microgrid Considering Operation Failures of Power Electronic Equipment

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Journal of Modern Power Systems and Clean Energy 2020年第1期8卷 111-123页

作者： wen zhong Lingfeng Wang Zhaoxi Liu Shiying Hou State Key Laboratory of Power Transmission Equipment&System Security and New Technology College of Electrical EngineeringChongqing UniversityChongqingChina Laboratory of Trustworthy Cyber-Physical Systems and Infrastructures Department of Electrical Engineering and Computer ScienceUniversity of Wisconsin-MilwaukeeMilwaukeeUSA

With the high integration of power electronic technologies in microgrids,the reliability assessment considering power electronic devices has become a hot ***,so far no research has considered the impact of the operation failure probability of power electronic equipment on the overall reliability of the *** paper aims to construct a holistic operation failure rate model of power electronic systems based on the overall reliability assessment of islanded microgrid with high penetration of renewable energy sources(RESs).In addition,to improve the reliability of islanded microgrid,the conventional battery energy storage system(BESS)is replaced by the hybrid energy storage system(HESS).Based on the proposed model,the operation failure models for the power electronic modules in microgrid are built and tested,and then the sensitivity analysis is performed for exploring the influence of various factors on the reliability of the microgrid.

关键词： Reliability assessment reliability improvement operation failure rate power electronics islanded microgrid

Immobilization and transformation of co-existing arsenic and antimony in highly contaminated sediment by nano zero-valent iron

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Journal of Environmental Sciences 2022年第2期34卷 152-160页

作者： Jianlong Guo Zhipeng Yin wen zhong Chuanyong Jing State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China School of Environmental Science and Engineering Shandong UniversityQingdao 266237China

Arsenic(As)and antimony(Sb)are usually coexistent in mine wastes and pose a great threat to human *** As immobilization by nano zero-valent iron(n ZVI)is promising,however,the stabilization for co-occurring As and Sb is not ***,the immobilization and transformation of As and Sb in n ZVI-treated sediments were evaluated using complementary leaching experiments and characterization *** sediment samples from a gold-antimony deposit revealed the co-existence of ultrahigh As and Sb at 50.3 and 14.9 g/kg,*** results show that As was more efficiently stabilized by n ZVI than Sb,which was primarily due to the soluble fraction that was readily absorbed by n ZVI of As was *** the n ZVI treatment proceeds,the oxidation and reduction of As and Sb occur simultaneously as evidenced by XPS *** primary oxidant,hydroxyl radicals,was detected by EPR studies,proving the occurrence of n ZVI induced Fenton *** study sheds light on differences in the interaction and immobilization of n ZVI with Sb and As in co-contaminated sediments.

关键词： Arsenic Antimony Nano zero-valent iron Immobilization Transformation Leaching