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Aerodynamics analysis of a hypersonic electromagnetic gun launched projectile

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Defence Technology（防务技术） 2020年第4期16卷 753-761页

作者： jian Shen Shao-bo Fan Ya-xin ji Qing-yu Zhu ji Duan College of Mechatronics Engineering North University of ChinaNo.3Xue Yuan RoadTai Yuan030051China Northwest Industries Group CO. Ltd.No.123Xing Fu Middle RoadXi'an710043China jilin jiangji Special Industries CO. Ltd.No.17Zun Yi West RoadJi Lin132021China AVIC China Aero-Polytechnology Establishment No.7Jing Shun RoadBeijing100028China

A hypersonic aerodynamics analysis of an electromagnetic gun(EM gun) launched projectile configuration is undertaken in order to ameliorate the basic aerodynamic characteristics in comparison with the regular projectile *** margin and pendulum motion analysis models have been applied to evaluate the flight stability of a new airframe *** a steady state computational fluid dynamics(CFD) simulation,the basic density,pressure and velocity contours of the EM gun projectile flow field at Mach number 5.0,6.0 and 7.0(angle of attack=0°) have been ***,the static margin values are enhanced dramatically for the EM gun projectile with configuration ***,lift and pitch property variations are all illustrated with the changes of Mach number and angle of attack.A particle ballistic calculation was completed for the pendulum *** results show that the configuration optimized projectile,launched from the EM gun at Mach number 5.0 to 7.0,acts in a much more stable way than the projectiles with regular aerodynamic layout.

关键词： Electromagnetic gun launched projectile Hypersonic aerodynamics Airframe configuration optimization Static margin Pendulum

Geometry Asymmetry of Mean Pulse Profile of Pulsar

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Chinese Physics Letters 1999年第4期16卷 307-309页

作者： PAN Jun WU xin-ji Department of Geophysics Peking UniversityBeijing 100871 Chinese Academic of Science-Peking University joint Beijing Astrophysical Center Beijing 100871

The effects of aberration,retardation and magnetic field sweep back,which are caused directly or indirectly by pulsar’s rapid rotation,are estimated in order to examine their influences on the geometry asymmetry of the mean pulse *** geometric asymmetry exhibits different behaviors at different *** millisecond pulsars incline to develop mean pulse profiles with asymmetric contrary to the normal *** pulsar J0437-4715 is analyzed as an example.

关键词： profile. pulsar rotation

Using concurrent lines in central catadioptric camera calibration

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第3期12卷 239-249页

作者： Lei ZHANG xin DU ji-lin LIU Department of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China

Central catadioptric cameras have been extensively adopted in robotics and surveillance due to their extensive field of *** attain precise 3D information in these applications,it is important to calibrate the catadioptric cameras *** existing calibration techniques either require prior knowledge of the mirror types,or highly depend on a conic estimation procedure,which might be ruined if there are only small portions of the conic visible on calibration *** this paper,we design a novel planar pattern with concurrent lines as a calibration rig,which is more robust in conic estimation since the relationship among lines is taken into *** on the line properties,we propose a rough-to-fine approach suitable for the new planar pattern to calibrate central catadioptric *** method divides the nonlinear optimization calibration problem into several linear sub-problems that are much more robust against *** calibration method can estimate intrinsic parameters and the mirror parameter simultaneously and accurately,without a priori knowledge of the mirror *** performance is demonstrated by both simulation and a real hyperbolic catadioptric imaging system.

关键词： Catadioptric Calibration Concurrent lines Conic estimation

NON-LINEAR OPTICAL IMAGING OF OBESITY-RELATED HEALTH RISKS:REVIEW

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Journal of Innovative Optical Health Sciences 2009年第1期2卷 9-25页

作者： THUC T.LE ji-xin CHENG Weldon School of Biomedical Engineering Purdue University West Lafayette Indiana 47907USA Department of Chemistry and Weldon School of Biomedical Engineering Purdue University West Lafayette Indiana 47907USA

This review highlights the recent applications of non-linear optical(NLO)microscopy to study obesity-related health risks.A strong emphasis is given to the applications of coherent anti-Stokes Raman scattering(CARS)microscopy where multiple non-linear optical imaging modalities including CARS,sum-frequency generation(SFG),and two-photon fluorescence are employed simultaneously on a single microscope *** examples on applications of NLO microscopy to study lipid-droplet biology,obesity-cancer relationship,atherosclerosis,and lipidrich biological structures are discussed.

关键词： Atherosclerosis coherent anti-Stokes Raman scattering lipid droplet mammary cancer non-linear optics obesity second harmonic generation sum-frequency generation twophoton fluorescence tumor stroma

Evaluating Helium Variations By Modeling Red Giant Branch Bump of Large Magellanic Cluster NGC 1978

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Research in Astronomy and Astrophysics 2022年第3期22卷 72-79页

作者： xin ji Cheng-Yuan Li Li-Cai Deng Key Laboratory for Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China School of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519082China Department of Astronomy School of Physics and AstronomyChina-West Normal UniversityNanchong 637002China

Many evidences show that the Multiple Population(MP)features exist not only in old clusters but also in intermediate-age clusters in the Megallanic Clouds(MCs),which are characterized by star-to-star abundance scatter of several elements,including helium(He).The red giant branch bump(RGBB)’s photometric properties are proved to be related to the variation in helium abundances of the member stars in star *** use the"Modules for Experiments in Stellar Astrophysics"(MESA)stellar evolution code to calculate the evolution sequences of stars along the red giant branch(RGB)with changing helium *** the RGB sequences,we then generate a luminosity function of the RGB stars within the grid of input helium abundances,which are compared with the observational data of an intermediate-age MC cluster NGC 1978.

关键词： globular clusters:general globular clusters:individual(NGC 1978) stars:abundances stars:Hertzsprung-Russell and C-M diagrams stars:luminosity function

A TRUST REGION-TYPE METHOD FOR SOLVINGMONOTONE VARIATIONAL INEQUALITY

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Journal of Computational Mathematics 2000年第1期18卷 13-24页

作者： Xi-ming Liang Cheng-Xian Xu ji-xin Qian Institute of Industrial Process Control National Lab of Industrial Control TechnologyZhejiang UniversityHangzhou 310027China School of Science Xi’an Jiaotong UniversityXi’an 710049China

Presents a study which proposed to introduce a trust region-type modification of Newton method for the monotone inequality problem using merit function. Concepts of monotone mapping; Proof of convergence of algorithm ... 详细信息

关键词： variational inequality problem trust region method global convergence quadratic convergence

Detection and analysis of serum bile acid profile in patients with colonic polyps

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World Journal of Clinical Cases 2024年第13期12卷 2160-2172页

作者： xin ji Hong Chen School of Medicine Southeast UniversityNanjing 210009Jiangsu ProvinceChina Department of Gastroenterology Zhongda Hospital Southeast UniversityNanjing 210009Jiangsu ProvinceChina

BACKGROUND Analyzing the variations in serum bile acid(BA)profile can provide a certain biological basis for early warning and prevention of various *** is currently no comprehensive study on the relationship between the serum BA profile and colonic *** To study the serum BA profile detection results of patients with colonic polyps,and analyze the correlation between BA and colonic *** From January 1,2022,to June 1,2023,204 patients with colonic polyps who were diagnosed and treated at Zhongda Hospital Southeast University were chosen as the study subjects,and 135 non-polyp people who underwent physical examination were chosen as the control *** all patients'clinical information,typical biochemical indicators,and BA *** Compared with the control group,the serum levels of taurocholic acid,glycocholic acid,glycochenodeoxycholic acid,and taurochenodeoxycholic acid in the colonic polyp group were significantly higher than those in the control group,while the content of deoxycholic acid(DCA)was lower than that in the control group(P<0.05).When colonic polyps were analyzed as subgroups,it was shown that there was a strong correlation between changes in the BA profile and polyp diameter,location,morphology,pathological kind,*** The serum BA profile showed significant changes in patients with colonic polyps,with a significant increase in primary conjugated BA content and a decrease in secondary free bile acid DCA *** is a certain correlation between primary free BA and pathological parameters of polyps.

关键词： Serum Bile acid profile Colonic polyps Bile acid metabolism

Salinity Acclimation Induces Reduced Energy Metabolism,Osmotic Pressure Regulation and Transcriptional Reprogramming in Hypotrichida Ciliate Gastrostyla setifera

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Journal of Ocean University of China 2024年第2期23卷 539-549页

作者： ji xin BI Luping ZOU Songbao LI Wenlu ji Daode ZHANG Qianqian School of Ocean Yantai UniversityYantai 264005China Key Laboratory of Coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone ResearchChinese Academy of SciencesYantai 264003China Zhejiang Institute of Freshwater Fisheries Huzhou 313001China Muping Coastal Environment Research Station Yantai Institute of Coastal Zone ResearchChinese Academy of SciencesYantai 264117China

Coastal and estuarine protists are frequently exposed to salinity *** the tolerance and stress responses of microalgae to salinity have been extensively studied,there have been scarce studies on the physiological response of heterotrophic protists to salinity *** this study,we investigated the physiological response of the heterotrophic ciliate Gastrostyla setifera to a salinity of 3,via a transcriptomic *** first transcriptome of genus Gastrostyla was obtained utilizing a group of manually isolated ciliate individuals(cells)and RNA-seq *** completeness of the transcriptome was *** expressed gene(DEG)analysis was performed among the transcriptomes of *** acclimated in saline water(salinity 3)and those cultured in fresh *** results demonstrated a significant alternation in gene transcription,in which the ciliate exhibits a transcripttomic acclimation in responding salinity *** up-regulated DEGs were enriched in the pathways of cytoskeleton proteins,membrane trafficking,protein kinases and protein *** may represent enhanced functions of ion transport,stress response and cell *** involved in energy metabolism and biosynthesis were markedly down-regulated,reflecting decreased cell ***,we detected significantly down-regulated genes involved in several pathways of amino acid catabolism,which may lead to accumulation of amino acids in the ciliate *** acid could act as compatible solutes in the cytoplasm to maintain the osmotic balance in saline ***,this work is an initial exploration to the molecular basis of the heterotrophic protist responding to salinity *** result sheds light on the mechanisms of enhancement of cell protection,reduction of cell activity,and osmotic pressure regulation in ciliates acclimated to salinity.

关键词： salinity stress heterotrophic protist ciliate Gastrostyla setifera transcriptome differentially expressed gene

Simultaneous approach for simulation of a high-temperature gas-cooled reactor

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第7期12卷 567-574页

作者： Yang CHEN jiang-hong YOU Zhi-jiang SHAO Ke-xin WANG ji-xin QIAN State Key Laboratory of Industrial Control Technology Zhejiang University Hangzhou 310027 China

The simulation of a high-temperature gas-cooled reactor pebble-bed module(HTR-PM) plant is *** lumped parameter model has the form of a set differential algebraic equations(DAEs) that include stiff equations to model point neutron *** nested approach is the most common method to solve DAE,but this approach is very expensive and time-consuming due to inner *** paper deals with an alternative approach in which a simultaneous solution method is *** DAEs are discretized over a time horizon using collocation on finite elements,and Radau collocation points are *** resulting nonlinear algebraic equations can be solved by existing *** discrete algorithm is discussed in detail;both accuracy and stability issues are ***,the simulation results are presented to validate the efficiency and accuracy of the simultaneous approach that takes much less time than the nested one.

关键词： Differential algebraic equations(DAEs) High-temperature gas-cooled reactor(HTR) Simulation Simultaneous approach