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Chinese Journal of Structural Chemistry 2006年第10期25卷 1243-1249页

作者： QIAN hui-Fen HUANG Wei LI hui-hui YAO cheng College of Sciences Nanjing University of Technology Nanjing 210009 China State Key Laboratory of Coordination Chemistry Coordination Chemistry Institute School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China

Chiral amino acids and their corresponding amino alcohols bearing camphoric backbone were prepared from D-（＋）-camphoric imide and characterized by infrared, elemental analysis, ESI-MS, and NMR measurements. Among them, one intermediate （1S,3R）-3-amino-2,2,3- trimethyl cyclopentane-1-carboxylic acid hydrochloride 3 was structurally elucidated by X-ray diffraction techniques. Versatile intermolecular hydrogen bonding interactions observed in its packing structure result in a two-dimensional framework.

关键词： chiral amino acids and amino alcohols (1S,3R)-3-amino-2,2,3-trimethyl-cyclopentane-1-carboxylic acid hydrochloride hydrogen-bonding interactions crystal structures

Optimization of the co-closing law of guide vanes and blades for bulb turbines based on CFD

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Journal of Hydrodynamics 2024年第2期36卷 363-377页

作者： hui Liu Yun-fa Lin Yong-guang cheng Song Xue Mao-jia Tang Jian Zhang Jia-yi fan State Key Laboratory of Water Resources Engineering and Management Wuhan UniversityWuhan430072China Dongfang Electric Machinery Co. Ltd.Deyang618000China

The load rejection transient process of bulb turbine units is critical to safety of hydropower stations,and determining appropriate closing laws of guide vanes(GVs)and runner blades(RBs)for this process is of *** this study,we proposed a procedure to optimize the co-closing law of GVs and RBs by using computational fluid dynamics(CFD),combined with the design of experiment(DOE)method,approximation model,and genetic optimization *** sensitivity of closing law parameters on the histories of head,speed,and thrust was analyzed,and a two-stage GVs’closing law associating with a linear RBs’closing law was *** results show that GVs dominate the transient characteristics by controlling the change of *** GVs’first-stage closing speed while shortening first-stage closing time can not only significantly reduce the maximum rotational speed but also suppress the water hammer pressure;slowing GVs’second-stage closing speed is conducive to controlling the maximum reverse axial *** directly affect the runner *** RBs’closing speed can further reduce the rotational speed and the maximum reverse axial *** safety margin of each control parameter,flow patterns,and pressure pulsations of a practical hydropower station were all improved after optimization,demonstrating the effectiveness of this method.

关键词： Bulb turbine load rejection transient process double regulation closing law optimization computational fluid dynamics(CFD)

Multi-agent decision support system for missile defense based on improved PSO algorithm

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Journal of Systems Engineering and Electronics 2017年第3期28卷 514-525页

作者： Zilong cheng Li fan Yulin Zhang College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China Academy of Equipment Beijing 101416China

Ballistic missile defense system (BMDS) is important for its special role in ensuring national security and maintaining strategic balance. Research on modeling and simulation of the BMDS beforehand is essential as developing a real one requires lots of manpower and resources. BMDS is a typical complex system for its nonlinear, adaptive and uncertainty characteristics. The agent-based modeling method is well suited for the complex system whose overall behaviors are determined by interactions among individual elements. A multi-agent decision support system (DSS), which includes missile agent, radar agent and command center agent, is established based on the studies of structure and function of BMDS. Considering the constraints brought by radar, intercept missile, offensive missile and commander, the objective function of DSS is established. In order to dynamically generate the optimal interception plan, the variable neighborhood negative selection particle swarm optimization (VNNSPSO) algorithm is proposed to support the decision making of DSS. The proposed algorithm is compared with the standard PSO, constriction factor PSO (CFPSO), inertia weight linear decrease PSO (LDPSO), variable neighborhood PSO (VNPSO) algorithm from the aspects of convergence rate, iteration number, average fitness value and standard deviation. The simulation results verify the efficiency of the proposed algorithm. The multi-agent DSS is developed through the Repast simulation platform and the constructed DSS can generate intercept plans automatically and support three-dimensional dynamic display of missile defense process.

关键词： agent-based modeling missile defense system decision support system (DSS) variable neighborhood negative selection particle swarm optimization (PSO)

A framework for equipment systems-of-systems effectiveness evaluation using parallel experiments approach

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Journal of Systems Engineering and Electronics 2015年第2期26卷 292-300页

作者： Zilong cheng Li fan Yulin Zhang College of Aerospace Science and Engineering National University of Defense Technology Academy of Equipment

Equipment systems-of-systems （SOS） effectiveness evaluation can provide important reference for construction and optimization of the equipment SoS. After discussing the basic theory and methods of parallel experiments, we depict an SoS effectiveness analysis and evaluation method using parallel expe- riments theory in detail. A case study is carried out which takes the missile defense system as an example. An artificial system of the missile defense system is constructed with the multi-agent modeling method. Then, single factor, multiple factors and defense position deployment computational experiments are carried out and evaluated with the statistical analysis method. Experiment re- sults show that the altitude of the secondary interception missile is not the key factor which affects SoS effectiveness and putting the defense position ahead will increase defense effectiveness. The case study demonstrates the feasibility of the proposed method.

关键词： agent based modeling parallel experiments computational experiments missile defense system effectiveness evaluation

New regularization method and iteratively reweighted algorithm for sparse vector recovery

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Applied Mathematics and Mechanics(English Edition) 2020年第1期41卷 157-172页

作者： Wei ZHU hui ZHANG Lizhi cheng Post-doctoral Research Station of Statistics School of Mathematics and Computational ScienceXiangtan UniversityXiangtan 411105Hunan ProvinceChina Department of Mathematics National University of Defense TechnologyChangsha 410073China

Motivated by the study of regularization for sparse problems,we propose a new regularization method for sparse vector *** derive sufficient conditions on the well-posedness of the new regularization,and design an iterative algorithm,namely the iteratively reweighted algorithm(IR-algorithm),for efficiently computing the sparse solutions to the proposed regularization *** convergence of the IR-algorithm and the setting of the regularization parameters are analyzed at ***,we present numerical examples to illustrate the features of the new regularization and algorithm.

关键词： regularization method iteratively reweighted algorithm(IR-algorithm) sparse vector recovery

Metre-size single-crystal graphene becomes a reality

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Science Bulletin 2017年第15期62卷 1039-1040页

作者： hui-Ming cheng Tsinghua-Berkeley Shenzhen Institute Tsinghua University Shenzhen 518055 China Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Center of Excellence in Environmental Studies (CEES) King Abdulaziz University Jeddah 21589 Saudi Arabia

*** Liu of Peking University,a well-known graphene researcher and also one of the authors for the work[1]highlighted here,has always said,‘‘Fabrication determines the future'.I *** growth of large-area high-quality ... 详细信息

关键词：石墨大规模生产铜基材料单晶化学气相沉积 Ni合金北京大学器件应用

An inversion decomposition test based on Monte Carlo response matrix on the γ-ray spectra from NaI(Tl) scintillation detector

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Nuclear Science and Techniques 2016年第4期27卷 181-192页

作者： Jian-Feng He Qi-fan Wu Jian-Ping cheng fang fang Yao-Zong Yang Jin-hui Qu Department of Engineering Physics Tsinghua University Beijing 100084 China Fundamental Science on Radioactive Geology and Exploration Technology Laboratory East China University of Technology Nanchang Jiangxi 330013 China College of Information Sciences and Technology Chengdu University of Technology Chengdu 610059 China Jiujiang Power Supply Subsidiary Company of State Grid Jiangxi Electronic Power Company Jiujiang 332000 China

The Na I(Tl) scintillation detector has a number of unique advantages, including wide use, high light yield,and its low price. It is difficult to obtain the decomposition of instrument response spectrum because of limitations associated with the Na I(Tl) scintillation detector's energy resolution. This paper, based on the physical process of c photons released from decay nuclides, generating an instrument response spectrum, uses the Monte Carlo method to simulate c photons with Na I(Tl) scintillation detector interaction. The Monte Carlo response matrix is established by different single energy γ-rays with detector effects. The Gold and the improved Boosted-Gold iterative algorithms have also been used in this paper to solve the response matrix parameters through decomposing tests,such as simulating a multi-characteristic energy c-ray spectrum and simulating synthesized overlapping peaks cray spectrum. An inversion decomposition of the c instrument response spectrum for measured samples(U series, Th series and U–Th mixed sources, among others)can be achieved under the response matrix. The decomposing spectrum can be better distinguished between the similar energy characteristic peaks, which improve the error levels of activity analysis caused by the overlapping peak with significant effects.

关键词：闪烁探测器矩阵分解蒙特卡洛 NaI γ射线反演光谱能量分辨率

Spectral energy distributions for TeV blazars

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Research in Astronomy and Astrophysics 2018年第10期18卷 19-32页

作者： Chao Lin Jun-hui fan Center for Astrophysics Guangzhou UniversityGuangzhou 510006China Astronomy Science and Technology Research Laboratory of Department of Education of Guangdong Province Guangzhou 510006China

In this work, we collected a sample of 69 TeV blazars from TeVCat, obtained their multi-wavelength observations, and fitted their spectral energy distributions by using a second degree poly-nomial function. The structure parameters of synchrotron bumps for 68 blazars and those of inverse- Compton bumps for 56 blazars were derived. Then, we conducted statistical analysis on the parame-ters （curvature, peak frequency, peak luminosity, bolometric luminosity and X/γ-ray spectral indexes）. From our analysis and discussions, we can conclude the following：（1） There is a clear positive correla-tion between the synchrotron peak frequency, log （Vp）^s, and the inverse-Compton peak frequency, log （Vp）^IC, and between the synchrotron peak luminosity, log （Vp）^sL（Vp）^s, and the inverse-Compton peak luminosity,log（Vp）^IC L（Vp）^IC. （2） The correlation between the peak frequency and the curvature of synchrotron bump is clearly different from that of the inverse-Compton bump, which further indicates that there are differ-ent emission mechanisms between them. （3） There is a correlation between log （Vp）^IC and γ-ray spectral index, αγ, for the TeV blazars： log （Vp）^IC = -（4.59 ± 0.30）αγ ＋（32.67 ±0.59）, which is consistent with previous work. （4） An ＂L-shape＂ relation is found between log（Vp）^s Up and αx for both TeV blazars and Fermi blazars. A significant correlation between log（Vp）^s and X-ray photon index （αx） is found for the TeV blazars with high synchrotron peak frequency： log（Vp）^s = -（3.20 ± 0.34）αx ＋（24.33 ± 0.79）, while the correlation is positive for low synchrotron peaked TeV sources. （5） In the αx -αγ diagram, there is also an ＂L-shape.＂ The anti-correlation is consistent with results available in the literature, and we also find a positive correlation between them. （6） Inverse-Compton dominant sources have luminous bolometric luminosities.

关键词： galaxies active - BL Lacertae objects general - quasars general - galaxies jets

PE-EDD:An efficient peer-effect-based financial fraud detection approach in publicly traded China firms

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CAAI Transactions on Intelligence Technology 2022年第3期7卷 469-480页

作者： hui Xia hui Ma Ping cheng School of accounting Chongqing University of TechnologyChongqingChina Chongqing Rural Commercial Bank ChongqingChina

Financial fraud arises from the exaggeration of business interests,and an accurate detection or prediction is a useful tool for both corporate management and capital market systems.A collection of computer technologies has been made on this problem so far,and one of the most important solutions is unsupervised learning *** them,most approaches work by analysing the internal relations in financial data and finding a new description of non-fraud ***,current studies focus a lot on the geometry attribute of financial data,while overlooking the obvious behaviour patterns and peer effects among *** has limited the accuracy of representation and furthermore the detection *** this work,a very general class of functions is allowed to represent firms,constraining them by peer effects between firms and presenting an error-distribution-based financial fraud firm detection *** results have shown great performance of the proposed approach.

关键词： detection financial fraud NMF peer effect

Comparison between TeV and non-TeV BL Lac Objects

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Research in Astronomy and Astrophysics 2016年第7期16卷 15-28页

作者： Chao Lin Jun-hui fan Center for Astrophysics Guangzhou University Guangzhou 510006 China Astronomy Science and Technology Research Laboratory of Department of Education of Guangdong Province Guangzhou 510006 China

BL Lacertae objects（BL Lacs） are the dominant population of Te V emitting blazars. In this work, we investigate whether there are any special observational properties associated with Te V *** do so, we will compare the observational properties of Te V detected BL Lacs（Te V BLs） with non-Te V detected BL Lac objects（non-Te V BLs）. From the 3rd Fermi/LAT source catalog（3FGL）, we can obtain662 BL Lacs, out of which 47 are Te V BLs and 615 are non-Te V BLs. Their multi-wavelength flux densities（FpR, FO, FX and Fγ）, photon spectral indexes（α^phXand α^phγ）, and effective spectral indexes（αRO and αOX）are compiled from the available literature. Then the luminosities（log ν LR, log ν LO, log ν LX, log ν Lγ）are calculated. From comparisons, we find that Te V BLs are different from low synchrotron peaked BLs and intermediate synchrotron peaked BLs, but Te V BLs show similar properties to high synchrotron peaked（HSP） BLs. Therefore, we concentrated on a comparison between Te V HSP BLs and non-Te V HSP *** results suggest that Te V HSP BLs and non-Te V HSP BLs exhibit some differences in their αRO and αphγ, but their other properties are quite similar.

关键词： galaxies active BL Lacertae objects general gamma rays galaxies