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Journal of Innovative Optical Health Sciences 2014年第6期7卷 97-104页

作者： lihui Yin Xuebo Zhang xiaodong li Shaohong Jin National Institutes for Food and Drug Control No.2 Tiantan Xili BeijingP.R.China

Samples of preparations contaminated by diethylene glycol(DEG),diethylene glycol raw materials and laboratory prepared solutions were measured to get NIR *** the iden-tification models were developed using the collected spectra and the spectra of distilled water,propylene glyool and the preparations without diethylene ***,the quantification model was also established for determining the concentration of diethylene glyool in the pre-parations.V alidation results show the identification and quantification models have ideal pre-diction *** emergency NIR models are rapid,easy to use and accurate,and can be implemented for identifying diethylene glycol raw material,screening the preparations contam-inated by diethylene glycol in the markets and analyzing the concentrations of DEG.

关键词： Diethylene glycol near-infrared transmittance reflectance spectroscopy identification quantification

Novel Hash Function Based on Coupled Chaotic Map Lattices

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Chinese Journal of Electronics 2014年第4期23卷 836-841页

作者： ZHEN Ping ZHAO Geng MIN Lequan li xiaodong School of Automation and Electrical Engineering University of Science and Technology Beijing Beijing Electronic Science and Technology Institute School of Mathematics and Physics University of Science and Technology Beijing

Hash function has been widely used in cryptographic field. This paper proposes a Hash function based on complexly Coupled chaotic map latices(CCML).It is equipped with new features of parallel and flexible processing. Parallelism indicates that the algorithm can reach high level of efficiency and speed. Flexibility means the length of Hash function and message block processed each time can be easily changed to adapt to practical demand. Experimental results show that the Hash function is one-way, with high plaintext sensitivity, as well as its strong capability for confusion and diffusion, and collision resistance. In comparison with MD5 and another Hash function based on chaos, the proposed Hash function shows good performance.

关键词： Hash function Parallelism Flexibility Coupled chaotic map lattice

The trapping effect of sulfur sensitization center Ag_2S cluster on T-grain AgBrI microcrystals

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Science China(Physics,Mechanics & Astronomy) 2004年第6期47卷 744-751页

作者： YANG Shaopeng FU Guangsheng li Xiaowei TIAN xiaodong College of Physics Science and Technology Hebei University Baoding 071002 China College of Physics Science and Technology Hebei University Baoding 071002 China College of Physics Science and Technology Hebei University Baoding 071002 China College of Physics Science and Technology Hebei University Baoding 071002 China

The microwave absorption dielectric-spectrum technique was used to study the decay kinetics of photoelectrons in sulfur-sensitized silver halide crystals. The time-resolution spectrum of free electrons and shallow-trapped electrons generated in sulfur-sensitized AgBrl crystals has been obtained. The relationship of the trapping effect of sensitization centers Ag2S and sensitization time or temperature in emulsions has been duscussed. With the increase in the sensitization time and temperature, the trap effect of sulfur sensitization centers varies from hole trap to shallow electron trap, and deep electron trap.

关键词： silver halide, sulfur-sensitized, photoelectron, trapping effect, microwave absorption dielectric-spectrum.

An intelligent market making strategy in algorithmic trading

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Frontiers of Computer Science 2014年第4期8卷 596-608页

作者： xiaodong li Xiaotie DENG Shanfeng ZHU Feng WANG Haoran XIE Department of Computer Science City University of Hong Kong Hong Kong China AIMS Lab Department of Computer Science and Engineering Shanghai Jiaotong University Shanghai 200240 China Shanghai Key Lab of Intelligent Information Processing Fudan University Shanghai 200433 China School of Computer Science Fudan University Shanghai 200433 China State Key Lab of Software Engineering School of Computer Science Wuhan University Wuhan 430072 China Department of Computer Science Hong Kong Baptist University Hong Kong China

Market making （MM） strategies have played an important role in the electronic stock market. However, the MM strategies without any forecasting power are not safe while trading. In this paper, we design and implement a twotier framework, which includes a trading signal generator based on a supervised learning approach and an event-driven MM strategy. The proposed generator incorporates the information within order book microstructure and market news to provide directional predictions. The MM strategy in the second tier trades on the signals and prevents itself from profit loss led by market trending. Using half a year price tick data from Tokyo Stock Exchange （TSE） and Shanghai Stock Exchange （SSE）, and corresponding Thomson Reuters news of the same time period, we conduct the back-testing and simulation on an industrial near-to-reality simulator. From the empirical results, we find that 1） strategies with signals perform better than strategies without any signal in terms of average daily profit and loss （PnL） and sharpe ratio （SR）, and 2） correct predictions do help MM strategies readjust their quoting along with market trending, which avoids the strategies triggering stop loss procedure that further realizes the paper loss.

关键词： algorithmic trading market making strategy or- der book microstructure news impact analysis market simulation

Analysis of the spatiotemporal trends and influencing factors of Hyphantria cunea in China

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Journal of Forestry Research 2024年第6期35卷 294-305页

作者： Hongwei Zhou Chaoqun Gong xiaodong li Yue Wang Yunbo Yan College of Computer and Control Engineering Northeast Forestry UniversityHarbin 150040People’s Republic of China Key Laboratory of National Forestry and Grassland Administration On Forest and Grassland Pest Monitoring and Warning Center for Biological Disaster Prevention and ControlNational Forestry and Grassland AdministrationShenyang 110034People’s Republic of China

In recent years,the situation of the Hyphantria cunea(Drury)(Lepidoptera:Erebidae),infestation in China has been serious and has a tendency to continue to spread.A comprehensive analysis was carried out to examine the spa-tial distribution trends and influencing factors of *** analysis involved integrating administrative division and boundary data,distribution data of ***,and envi-ronmental variables for *** and gravity analysis techniques were employed for data processing and *** results show that *** exhibited high aggregation patterns in 2021 and 2022 concentrated mainly in eastern *** these years,the focal point of the infestation was in Shandong Province with a spread towards the *** such as high vegetation density in eastern China provided favorable situations for growth and development of *** China,the spatial distribution of the moth is primarily influenced by two critical factors:precipitation during the driest month and *** play a pivotal role in determining the spread of the *** on these results,suggestions are provided for a mul-tifaceted approach to prevention and control of *** infestation.

关键词： Hyphantria cunea Temporal trends GeoDetector spatial analysis Spatial heterogeneity

Transcriptome analysis of the Chinese grass shrimp Palaemonetes sinensis(Sollaud 1911) and its predicted feeding habit

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Journal of Oceanology and limnology 2018年第5期36卷 1778-1787页

作者： li Yingdong XUE Huiling li xiaodong College of Animal Science and Veterinary Medicine Shenyang A gricultural UniversityShenyang 110866China

Chinese grass shrimp P alaemonetes sinensis is an economically important freshwater shrimp in China. However, wild resources of grass shrimp have declined dramatically due to overfishing and environmental destruction. Previous studies of P. sinensis are basic and sparse due to the lack of genomic data. In this study, the first transcriptome dataset of P. sinensis was obtained by performing de novo RNA sequencing. A total of 100 644 unigenes and 17 019 simple sequence repeats were identified. Potential genes and their functions were annotated by analysis of public databases. Genes encoding digestive enzymes in P. sinensis, including those specific for proteinase, carbohydrase, lipidase, as well as other related important genes, are described. The first transcriptomic investigation of P. sinensis may provide comprehensive sequence resources for grass shrimp study. Additionally, the data generated here will contribute to the identification of biomarkers for grass shrimp, and may help in understanding the links between digestive enzymes and food habit.

关键词： transcripts Palaemonetes sinensis digestive enzymes feeding habit

CO_2 solubility in aqueous solutions of N-methyldiethanolamine+piperazine by electrolyte NRTL model

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Science China Chemistry 2016年第3期59卷 360-369页

作者： Jicai Huang Maoqiong Gong Xueqiang Dong xiaodong li Jianfeng Wu Technical Institute of Physics and Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences School of Energy and Power Engineering Beihang University

Accurate modeling of the solubility behavior of CO_2 in the aqueous alkanolamine solutions is important to design and optimization of equipment and process. In this work, the thermodynamics of CO_2 in aqueous solution of N-methyldiethanolamine(MDEA) and piperazine(PZ) is studied by the electrolyte non-random two liquids(NRTL) model. The chemical equilibrium constants are calculated from the free Gibbs energy of formation, and the Henry's constants of CO_2 in MDEA and PZ are regressed to revise the value in the pure water. New experimental data from literatures are added to the regression process. Therefore, this model should provide a comprehensive thermodynamic representation for the quaternary system with broader ranges and more accurate predictions than previous work. Model results are compared to the experimental vapor-liquid equilibrium(VLE), speciation and heat of absorption data, which show that the model can predict the experimental data with reasonable accuracy.

关键词： N-methyldiethanolamine piperazine carbon dioxide electrolyte NRTL

Preparation of Gd_2O_2S:Pr Scintillation Ceramics by Pressureless Reaction Sintering Method

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Journal of Materials Science & Technology 2009年第2期25卷 254-258页

作者： Jingbao lian Xudong Sun Tie Gao Qiang li xiaodong li Zhigang liu Key Laboratory for Anisotropy and Texture of Materials （Ministry of Education） School of Materials and Metallurgy Northeastern University Shenyang 110004 China Key Laboratory for EPM of Ministry of Education Northeastern University Shenyang 110004 China College of Materials ＆ Chemical Engineering Liaoning Institute of Technology Jinzhou 121001 China

Fabrication of Gd2O2S：Pr scintillation ceramics by 2Gd2O3.（Gd,Pr）2（SO4）***2O precursor was made Gd2O3, Pr6O11 and H2SO4 as the starting materials pressureless reaction sintering was investigated. The by hydrothermal reaction using commercially available Then single phase Gd2O2SO4：Pr powder was obtained by calcining the precursor at 750℃ for 2 h. The Gd2O2SO4：Pr powder compacts can be sintered to single phase Gd2O2S：Pr ceramics with a relative density of 99% and mean grain size of 30um at 1750℃ for 2 h in flowing hydrogen atmosphere. Densification and microstructural development of the Gd2O2S：Pr ceramics were examined. Luminescence spectra of the Gd2O2S：Pr ceramic under 309 nm UV excitation and X-ray excitation show a green emission at 511 nm as the most prominent peak, which corresponds to the ^3p0-3H4 transition of Pr^3＋ ions.

关键词： Scintillation ceramics Gd2O2S Pressureless reaction sintering X-ray excited luminescence (XEL)

A bipolar modified separator using TiO2 nanosheets anchored on N-doped carbon scaffold for high-performance li–S batteries

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Journal of Materials Science & Technology 2020年第20期52卷 152-158页

作者： Na li Fei Chen Xiangtao Chen Zhongxu Chen Yang Qi xiaodong li Xudong Sun Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China College of Environmental and Chemical Engineering Dalian UniversityDalian 116622China

lithium-sulfur batteries hold promise for next generation batteries due to their high theoretical energy density and low ***,the rapid capacity fading caused by the shuttle of polysulfide between two electrodes severely hinders the practical application of li-S *** address the issue,we reported a three-dimensional heterostructured TiO2 nanosheets/N-doped carbon(TO/NC),which is coated on a commercial polypro pylene(PP) separator,as an efficient barrier for li-S *** TO/NC coating layer provides a bipolar chemical adsorption of lithium polysulfides(liPSs) via TiO2 nanosheets with exposed(001) facets and N-doped carbon,showing high trapping capacity and remarkable electrocatalytic activity for *** slurry-bladed carbon black/sulfur cathode with 64 wt% sulfur offers outstanding performance with an initial capacity of 1314 mAh g^-1 at 0.2 *** 900 cycles,the cell still maintains the capacity of 448 mA h g^-1 at a 1 C rate with a degradation rate of only 0.055% per *** separator reported in this work holds great promise for the development of high-energy li-S batteries.

关键词： lithium-sulfur batteries N-doped carbon Separator TiO2 Nanosheets

Three-dimensional Electromagnetic Characteristics Analysis of Novel linear Synchronous Motor under Lateral and Yaw Conditions of MAGLEV

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CES Transactions on Electrical Machines and Systems 2022年第1期6卷 29-36页

作者： Gang Lv Zhixuan Zhang xiaodong li IET School of Electrical Engineering Beijing Jiaotong UniversityBeijing 100044China IEEE Macao University of Science and Technology Faculty of Innovation EngineeringMacao999078China

Dynamic stability analysis of superconducting electro-dynamic maglev train under lateral and yawing motion condition is the key research *** novel three-dimensional electromagnetic model of integrated linear synchronous motor in electro-dynamic maglev train with yawing operation condition is proposed,which can not only simultaneously achieve the propulsion,levitation and guidance performances of maglev vehicle,but also analyze the dynamic stability performance of train with yawing *** three-dimensional analytical method is introduced for analyzing the electromagnetic force characteristics of the linear synchronous motor with the yawing operation ***,the topology structure and operation principle of the linear synchronous motor with yawing attitude are ***,the three-dimensional analytical model and expressions of electromagnetic characteristics are obtained by equivalent circuit method and Fourier decomposition method,such as levitation force,guidance force,propulsion force and yawing torque,***,the three-dimensional electromagnetic characteristics of the linear synchronous motor are calculated under yawing operation conditions of maglev train,and the correctness of the analytical theory is verified by the finite element analysis and measured data on the test line.

关键词： electro-dynamic maglev system linear synchronous motor propulsion levitation and guidance three-dimensional electromagnetic characteristics