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Science China(Information Sciences) 2013年第1期56卷 78-97页

作者： qian ju CHEN Lin XU BaoWen College of Computer Science and Technology Nanjing University of Aeronautics and Astronautics State Key Laboratory for Novel Software Technology Nanjing University

With the keyword synchronized,Java provides a simple but often over-used synchronization *** programmers tend to use a big synchronized section to protect a large block of statements even if many of them are unnecessarily *** coarse-gained synchronizations may increase lock contention and thereby decrease the performance of a program,especially in a multi-core *** decrease in performance may affect the quality of service provided by the software and hence make the software less *** ensure trustworthiness,this paper proposes a source-code level refactoring approach to optimize coarse-gained *** exploits dependence and escape information to search for shrinkable critical sections and can transform them into smaller ones *** approach can be used to gradually evolve concurrent code for better *** the approach,to achieve more optimizations,we develop a new escape analysis,named escape state analysis,which can not only tell us whether an object finally escapes but also determine the escape states of objects at each program *** such an analysis,more refactoring opportunities can be *** build a tool and test our refactoring approach on several benchmark *** results show that the proposed approach does make effective refactoring suggestions for the users.

关键词： concurrent synchronization refactoring dependence escape analysis

Microbiome changes:an indicator of Parkinson’s disease?

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Translational Neurodegeneration 2019年第1期8卷 483-491页

作者： Caroline Haikal qian-qian Chen jia-Yi Li Neural Plasticity and Repair Unit Wallenberg Neuroscience CenterDepartment of Experimental Medical ScienceBMC A1022184 LundSweden Institute of Neuroscience College of Life and Health SciencesNortheastern UniversityShenyangLiaoningChina Institute of Health Sciences China Medical UniversityShenyang 110112China

Parkinson’s disease is characterized by dopaminergic neuron loss and intracellular inclusions composed mainly of alpha synuclein(α-syn),but the mechanism of pathogenesis is still *** recent years,more attention has been given to the gut as a key player in the initiation and progression of PD *** studies characterizing changes in the microbiome,particularly the gut microbiome,have been *** many studies found a decrease in the bacterial family Prevotellaceae and in butyrate-producing bacterial genera such as Roseburia and Faecalibacteria,and an increase in the genera Akkermansia many of the studies reported contradictory *** this review,we highlight the findings from the different studies and reflect on the future of microbiome studies in PD research.

关键词： Parkinson’s disease Intestinal microbiota Inflammation Gut Protein aggregation

Revision of the photometric parameters of BS Cassiopeiae

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Research in Astronomy and Astrophysics 2010年第6期10卷 569-576页

作者： jia-jia He Sheng-Bang qian Miloslav Zejda Zdenek Mikulasek National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China Key Laboratory for the Structure and Evolution of Celestial Objects National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China Institute of Theoretical Physics and Astrophysics Masaryk University Kotlarska 2 611 37 Brno Czech Republic Observatory and Planetarium of J. Palisa VSB- Technical University Ostrava Czech Republic

Seven charge-coupled device （CCD） photometric times of light minimum of the overcontact binary BS Cas which were obtained from 2007 August to November and one CCD light curve in the R band which was observed on 2007 September 24 and October 15, are presented. It is found that the light curve ofBS Cas has characteristics like a typical EW-type light variation. The light curve obtained by us is symmetric and shows total eclipses, which is very useful for determining photometric parameters with high precision. Photometric solutions were derived by using the 2003 version of the Wilson-Devinney code. It shows that BS Cas is a W-subtype overcontact binary （f = 27.5% ± 0.4%） with a mass ratio of q = 2.7188± 0.0040. The temperature difference between the two components is 190 K. Analysis of the 042 curve suggests that the period of AE Phe shows a long-term continuous decrease at a rate of dP/dt = - 2.45 × 10^-7 d yr^- 1 The long-time period decrease can be explained by mass transfer from the primary to the secondary.

关键词： stars binaries close -- stars binaries eclipsing -- stars individual BS Cas

Study on concentration and turbulence of solid-liquid FAE in dispersal process

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Defence Technology（防务技术） 2018年第6期14卷 657-660页

作者： jia-chen Chen Xin Ma Qiu-ju Ma China Zhongyuan Engineering Corporation Beijing 100191China China Ordnance Society Beijing 100089China College of Resources&Safety Engineering China University of Mining&Technology(Beijing)Beijing 100083China

This paper describes numerical simulation on dispersion of the solid-liquid mixed fuel driven by explosion load. A model used in numerical calculation for dispersion of solid-liquid mixed fuel was established in this study. The concentration and turbulent intensity in the multiphase cloud of the solidliquid mixed fuel were obtained by numerical simulation. It was found that the fuel concentration tended to be 0.15 kg/m^3, the turbulence intensity tended to be 7 in 90 ms. The numerical results agree with those measured in the experiment.

关键词： Solid-liquid mixed fuel Concentration Turbulence intensity Numerical simulation

Intermediate mass dilepton production in a chemically equilibrating quark-gluon matter

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Nuclear Science and Techniques 2003年第1期14卷 53-55页

作者： HE Ze-jun ZHANG jia-ju 等 CCAST（worldLaboratory)P.O.Box8730 Beijing100080 ShanghaiInstituteofnuclearResearch theChineseAcademyofSciencesShanghai201800

We find that in a chemically equilibrating baryon-rich quark-gluon matter, due to the slow cooling rate, high initial temperature, large gluon density as well as large fusion cross section ofin the intermediate mass region, the gluon fusion provides a dominant contribution to dileptons with intermediate masses, resulting in the significant enhancement of intermediate mass dileptons.

关键词：高能重离子碰撞 RHZC 放射性原子核化学平衡 QGM LHC TES

Relationship between space charge and nonlinear characteristics of ZnO varistor

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Science China(Technological Sciences) 2011年第7期54卷 1771-1778页

作者： WANG qian TU YouPing DING Lijian ju ZeLi Beijing Key Laboratory of High Voltage & EMC North China Electric Power University Beijing 102206 China

In order to reveal the conduction mechanism of ZnO varistor, the pulsed electroacoustic (PEA) measurement is employed to investigate the space charge distribution characteristics of ZnO varistors under different current densities in this paper. Experimental results show that the relationship between the space charge and the current density is consistent with the voltage-current characteristics, and can reflect the nonlinear characteristics of ZnO varistor. The space charge increases linearly with the increase of the electric field strength and the current density in the small current region, this reflects the decrease of the surface states of the grain boundary and changes of the Schottky barrier. There exists a transition region between the small current and middle current regions, where the current is composed of the current by the emission of thermally activated electrons and the tunneling current. In the middle current region, the space charge will decrease as the current increases, and will disappear with the depletion layer decreasing to zero.

关键词： ZnO varistors pulsed electroacoustic (PEA) measurement space charge double Schottky barrier

Study of Human Action Recognition Based on Improved Spatio-temporal Features

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International Journal of Automation and computing 2014年第5期11卷 500-509页

作者： Xiao-Fei Ji qian-qian Wu Zhao-Jie ju Yang-Yang Wang School of Automation Shenyang Aerospace University School of Computing University of Portsmouth

Most of the exist action recognition methods mainly utilize spatio-temporal descriptors of single interest point while ignoring their potential integral information, such as spatial distribution information. By combining local spatio-temporal feature and global positional distribution information(PDI) of interest points, a novel motion descriptor is proposed in this paper. The proposed method detects interest points by using an improved interest point detection method. Then, 3-dimensional scale-invariant feature transform(3D SIFT) descriptors are extracted for every interest point. In order to obtain a compact description and efficient computation, the principal component analysis(PCA) method is utilized twice on the 3D SIFT descriptors of single frame and multiple frames. Simultaneously, the PDI of the interest points are computed and combined with the above features. The combined features are quantified and selected and finally tested by using the support vector machine(SVM) recognition algorithm on the public KTH dataset. The testing results have showed that the recognition rate has been significantly improved and the proposed features can more accurately describe human motion with high adaptability to scenarios.

关键词： Action recognition spatio-temporal interest points 3-dimensional scale-invariant feature transform (3D SIFT) positional distribution information dimension reduction

Fast Carrier Selection of JPEG Steganography Appropriate for Application

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Tsinghua Science and Technology 2020年第5期25卷 614-624页

作者： Weixiang Ren Yibo Xu Liming Zhai Lina Wang ju jia the Key Laboratory of Aerospace Information Security and Trusted Computing Ministry of EducationWuhan UniversityWuhan 430000China the School of Cyber Science and Engineering Wuhan UniversityWuhan 430000China Micropattern Co.Ltd. Wuhan 430000China

In recent years,the improvement of the security of steganography mainly involves not only carrier security but also distortion *** the actual environment,the existing method of carrier selection is limited by its complex algorithm and slow running speed,making it not appropriate for rapid *** study proposes a method for selecting carriers and improving the security of *** images are decompressed to spatial *** correlation coefficients between two adjacent pixels in the horizontal,vertical,counter diagonal,and major diagonal directions are *** mean value of the four correlation coefficients is used to evaluate the security of each JPEG *** images with low correlation coefficients are considered safe carriers and used for embedding in our *** experimental results indicate that the stego images generated from the selected carriers exhibit a higher anti-steganalysis capability than those generated from the randomly selected *** the premise of the same security level,the images with low correlation coefficients have a high *** algorithm has a very fast running speed,and the running time of a 2048×2048 image is less than 1 s.

关键词： steganography steganalysis carrier JPEG correlation coefficients

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中药多糖药理活性最新研究进展

化学试剂 2025年第1期47卷 1-8页

作者：吕嘉璐霍燕菊张翼黑龙江中医药大学教育部北药基础与应用研究重点实验室黑龙江哈尔滨150036 黑龙江中医药大学第一临床医学院黑龙江哈尔滨150036

近年来,中药多糖因较低的毒副作用,多样的药理活性以及广阔的应用前景,成为天然药物开发及应用研究的热点。对近5年的中药多糖研究进行了追踪,汇总整理了中药多糖发挥的抗肿瘤、免疫调节、糖脂代谢、肠道菌群、抗氧化及其他药理活性,并... 详细信息

近年来,中药多糖因较低的毒副作用,多样的药理活性以及广阔的应用前景,成为天然药物开发及应用研究的热点。对近5年的中药多糖研究进行了追踪,汇总整理了中药多糖发挥的抗肿瘤、免疫调节、糖脂代谢、肠道菌群、抗氧化及其他药理活性,并对影响中药多糖药理活性的因素进行了剖析。分析了当前中药多糖研究中存在的局限性,并对未来中药多糖的应用前景进行展望,旨在提高中药材的利用率,明确中药多糖的药理活性,从而加速中药多糖的成果转化及应用推广。

关键词：中药多糖药理活性抗肿瘤免疫调节肠道代谢稳态调节作用机制

Printed flexible thin-film transistors based on different types of modified liquid metal with good mobility

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Science China(Information Sciences) 2019年第10期62卷 182-193页

作者： qian LI ju LIN Tianying LIU Han ZHENG Jing LIU Beijing Key Lab of Cryo-Biomedical Engineering and Key Lab of Cryogenics Technical Institute of Physics and ChemistryChinese Academy of Sciences Department of Biomedical Engineering School of MedicineTsinghua University School of Engineering Science University of Chinese Academy of Sciences Beijing DREAM Ink Technologies Co. Ltd.

High-performance logic circuits fabricated on flexible or unconventional substrates have become a necessity for several new applications. Generally, compared to those fabricated on more rigid substrates,printed, large-area, and flexible thin film transistors(TFTs) are prone to under-performance, which severely limits their practical value. The realization of printed flexible macroelectronics requires advancements in material science and novel fabricating techniques. In this study, using a fast printing process, we manufacture liquid metal-carbon nanotube TFTs on a thin polyethylene terephthalate substrate. These flexible TFTs(ptype) exhibit enhance stability and flexibility, carrier mobility(10.61 cm2V-1s-1), and transconductance(0.88 μS). Furthermore, we realize dependable n-type and ambipolar transistors based on liquid metals with charge transport efficiencies that are comparable to our p-type counterparts, thus providing a foundation for manufacturing integrated circuits and complementary logic gates on flexible substrates. This study shows the positive progress of liquid metal printing-enabled functional devices and discusses the possibility of practical applications; moreover, it sets the foundation for printed high-performance and large-area flexible liquid metal electronics.

关键词： liquid metal carbon nanotube field-effect transistors printed devices carrier mobility