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Research on the influences of motion characteristics of jetting projectile charge under water

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Defence Technology（防务技术） 2024年第3期33卷 411-425页

作者： Xing chen yong-gang Lu Institute of Systems Engineering China Academy of Engineering PhysicsMianyang 621900SichuanChina

Shaped charge warhead is important for enhancing the damage performance of underwater *** paper used finite element analysis software and based on JPC water penetration experiments to examine the influence of liner parameters(wall thickness,material),charge aspect ratio,and stand-off distance on the movement characteristics of JPC in *** findings reveal that the head diameter of the JPC increases and experiences significant erosion after entering the water,the effective length of the JPC in water undergoes two distinct phases:a growth phase and a decrease phase,with the velocity of the JPC decaying *** the liner thickness,stand-off distance and the charge aspect ratio can improve the erosion resistance and the velocity retention capacity of the *** optimal ranges for liner thickness and stand-off distance are 0.0363D_(k) to 0.0545D_(k)(D_(k) is the charge diameter),the stand-off distance should be within 1.0D_(k).After the charge aspect ratio higher than 1.25,the charge structure exerts minimal influence the movement characteristics of the JPC in *** density plays a crucial role in the velocity decay pattern of the JPC during *** with higher densities exhibit superior velocity retention capabilities in water,with the velocity decay pattern converging if the densities are ***,copper,tantalum and tungsten liners are deemed appropriate for underwater shaped charge ***,the results will provide an important reference for the design of underwater shaped charge warhead.

关键词： JPC Movement characteristics Underwater penetration Numerical simulation

Development of a high-repetition-rate lumped-inductance kicker magnet prototype for the beam switchyard of SHINE

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Nuclear Science and Techniques 2024年第2期35卷 20-31页

作者： yong-Fang Liu Rui-Ping Wang Jin Tong Bo Zhang Si chen Qi-bing Yuan Hai-Xiao Deng Ming Gu Bo Liu Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201412People’s Republic of China

The Shanghai high-repetition-rate X-ray free-electron laser and extreme light facility(SHINE)operates at a maximum repetition rate of 1 *** magnets are key components that distribute electron bunches into three different undulator lines in a bunch-by-bunch *** kicker field width must be less than the time interval between bunches.A lumpedinductance kicker prototype was developed using a vacuum chamber with a single-turn *** full magnetic field strength was 0.005 *** paper presents the requirements,design considerations,design parameters,magnetic field calculations,and measurements of the kicker *** relevant experimental results are also *** pulse width of the magnetic field was approximately 600 ns,and the maximum operation repetition rate was 1 *** developed kicker satisfies the requirements for the SHINE ***,numerous recommendations for the future optimization of kicker magnets are provided.

关键词： X-ray free-electron laser Kicker magnet Beam switchyard High repetition rate Ni-Zn ferrites

Physics-Informed Neural Networks with Two Weighted Loss Function Methods for Interactions of Two-Dimensional Oceanic Internal Solitary Waves

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Journal of Systems Science & Complexity 2024年第2期37卷 545-566页

作者： SUN Junchao chen yong TANG Xiaoyan School of Mathematical Sciences Key Laboratory of Mathematics and Engineering Applications(Ministry of Education)&Shanghai Key Laboratory of PMMPEast China Normal UniversityShanghai 200241China College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao 266590China

The multiple patterns of internal solitary wave interactions(ISWI)are a complex oceanic *** remote sensing techniques indirectly detect these ISWI,but do not provide information on their detailed structure and ***,the authors considered a three-layer fluid with shear flow and developed a(2+1)Kadomtsev-Petviashvili(KP)model that is capable of describing five types of oceanic ISWI,including O-type,P-type,TO-type,TP-type,and *** learning models,particularly physics-informed neural networks(PINN),are widely used in the field of fluids and internal solitary ***,the authors find that the amplitude of internal solitary waves is much smaller than the wavelength and the ISWI occur at relatively large spatial scales,and these characteristics lead to an imbalance in the loss function of the PINN *** solve this problem,the authors introduce two weighted loss function methods,the fixed weighing and the adaptive weighting methods,to improve the PINN *** successfully simulated the detailed structure and dynamics of ISWI,with simulation results corresponding to the satellite *** particular,the adaptive weighting method can automatically update the weights of different terms in the loss function and outperforms the fixed weighting method in terms of generalization ability.

关键词： Internal solitary wave interactions KP equation PINN method weighted loss function method

The CAD/CAM Solution and Realization for Machining Large Scale Steel-concrete Objects

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厦门大学学报（自然科学版） 2002年第S1期41卷 14-15页

作者： ZHENG yong-qian, chen bing-sen, ZHANG Wei-min, FAN Liu-qun (Department of Mechanical Engineering, Tongji University, Shanghai 200092, China)

First the architecture of the integrated CAD/CAM system developed for machining large scale steel-concrete girders using I-DEAS and other developing tools are introduced; then the involved technologies in the development of the system are presented, which include the method for determining the position and orientation of the manufacturing features, the method for geometrical modeling of the girders, the techniques for generating the toolpaths for the 5-axis machining centers, the generative process planning technique and the postprocssing technique for the specific machines etc. Moreover some related special technical issues are also discussed. The CAD/CAM system is a network-based workshop-oriented manufacturing system, in which every machining cell can work independently serving two machining lines. The cell server take charge of the management of work schedules, personnel, machining resources, databases etc. the control computer serves to monitor the whole manufacturing lines, to arrange tasks, and to communicate; the two CAD/CAM workstations’ work is to model the girders using the CAD data, to plan the process and to generate the NC programs. The CL files that describe the toolpaths generated are ATP-format files. In order to translate them into NC codes that can be directly used by the 5-axis machining centers, a specific postprocessing program is developed for these distinct machines. The system has been successfully realized and applied in Shanghai Maglev Transrapid project. In the developing process, the following technical problems are solved: 1. Algorithms for measuring, positioning, and machining complex objects. 2. Methods for Modeling. 3. Animation and postprocess techniques for 5-axis machining centers. 4. Technologies for machining large-scale concrete-steel structures Although further evolution is needed for this system, the facts have proven its performance satisfactory and the technologies and the methods developed suitable.

关键词： maglev transrapid CAD/CAM manufacturing feature Pseudo-NC Real-NC post process

High-order Soliton Matrix for the Third-order Flow Equation of the Gerdjikov-Ivanov Hierarchy Through the Riemann-Hilbert Method

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 358-378页

作者： Jin-yan ZHU yong chen School of Mathematical Sciences Shanghai Key Laboratory of Pure Mathematics and Mathematical PracticeEast China Normal UniversityShanghai 200062China College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao 266590China

The Gerdjikov-Ivanov(GI)hierarchy is derived via recursion operator,in this article,we mainly investigate the third-order flow GI *** the framework of the Riemann-Hilbert method,the soliton matrices of the third-order flow GI equation with simple zeros and elementary high-order zeros of Riemann-Hilbert problem are constructed through the standard dressing *** advantage of this result,some properties and asymptotic analysis of single soliton solution and two soliton solution are discussed,and the simple elastic interaction of two soliton are *** with soliton solution of the classical second-order flow,we find that the higher-order dispersion term affects the propagation velocity,propagation direction and amplitude of the ***,by means of a certain limit technique,the high-order soliton solution matrix for the third-order flow GI equation is derived.

关键词： Gerdjikov-Ivanov hierarchy third-order flow GI equation Riemann-Hilbert method high-order soliton

Long-time Asymptotics for the Reverse Space-time Nonlocal Hirota Equation with Decaying Initial Value Problem:without Solitons

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 708-727页

作者： Wei-qi PENG yong chen School of Mathematical Sciences East China Normal UniversityShanghai 200241China College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao 266590China

In this work,we mainly consider the Cauchy problem for the reverse space-time nonlocal Hirota equation with the initial data rapidly decaying in the solitonless *** from the Lax pair,we first construct the basis Riemann-Hilbert problem for the reverse space-time nonlocal Hirota ***,using the approach of Deift-Zhou nonlinear steepest descent,the explicit long-time asymptotics for the reverse space-time nonlocal Hirota is *** the reverse space-time nonlocal Hirota equation,since the symmetries of its scattering matrix are different with the local Hirota equation,the v(λ_(i))(i=0,1)would like to be imaginary,which results in theδ_(λi)^(0)contains an increasing t(±Imv(λ_(i)))/2,and then the asymptotic behavior for nonlocal Hirota equation becomes differently.

关键词： Riemann-Hilbert problem reverse space-time nonlocal Hirota equation long-time asymptotics nonlinear steepest descent method

Effect of recombinant human growth hormone and interferon gamma on hepatic collagen synthesis and proliferation of hepatic stellate cells in cirrhotic rats

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Hepatobiliary & Pancreatic Diseases International 2012年第3期11卷 294-301页

作者： yong-Hua chen, bing-Qing Du, Zhen-Jiang Zheng, Guang-Ming Xiang, Xu-Bao Liu and Gang Mai Department of Hepatobiliopancreatic Surgery, West China Hospital, Sichuan University, chengdu 610041, China Department of Hepatobiliopancreatic Surgery West China Hospital Sichuan University Chengdu 610041 China

BACKGROUND: Fibrosis plays a key role in the development of liver cirrhosis. In this study, we investigated the effect of growth hormone and interferon gamma on hepatic collagen synthesis and the proliferation of hepatic stellate cells in a cirrhotic rat model. METHODS: Cirrhosis was induced in rats using carbon tetrachloride. Rats were simultaneously treated with daily subcutaneous injections of recombinant human growth hormone or interferon gamma combined with recombinant human growth hormone. The control group was given saline. The relative content of type I and type IV collagen was assessed by indirect immunofluorescence analysis. Activated hepatic stellate cells were prepared from cirrhotic rats. The 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H-tetrazolium bromide (MTT) method was used to assess the effects of recombinant human growth hormone and interferon gamma on these cells in vitro. RESULTS: Both qualitative and quantitative analysis showed that type I and type IV collagen secretion increased with time after recombinant human growth hormone administration and was significantly higher than control and recombinant human growth hormone combined with interferon gamma administration. In vitro, recombinant human growth hormone significantly stimulated hepatic stellate cell proliferation in a concentration-dependent manner (10 -3 -10 -1 mg/100 μL), andinterferon gamma (10 -2 -10 -1 μg/100 μL) significantly inhibited their growth compared to the control group. Interferon gamma combined with recombinant human growth hormone eliminated this growth-promoting effect to a certain degree in a concentration-dependent manner (10 -1 μg/100 μL, P0.05) and a time-dependent manner (P<0.05). CONCLUSIONS: Recombinant human growth hormone increased collagen secretion in cirrhotic rats in vivo and promoted the proliferation of hepatic stellate cells from cirrhotic rats in vitro. It is possible that concurrent interferon gamma therapy can offset

关键词： growth hormone interferon gamma hepatic stellate cell liver cirrhosis collagen

The Role of Adipose Tissue-derived Exosomes in Chronic Metabolic Disorders

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Current Medical Science 2024年第3期44卷 463-474页

作者： Rui HE yong chen Division of Endocrinology Department of Internal MedicineTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Laboratory of Endocrinology & Metabolism Key Laboratory of Vascular Aging of the Ministry of EducationTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Branch of National Clinical Research Center for Metabolic Diseases Wuhan430030China

Excessive fat deposition in obese subjects promotes the occurrence of metabolic diseases,such as type 2 diabetes mellitus(T2DM),cardiovascular diseases,and non-alcoholic fatty liver disease(NAFLD).Adipose tissue is not only the main form of energy storage but also an endocrine organ that not only secretes adipocytokines but also releases many extracellular vesicles(EVs)that play a role in the regulation of whole-body *** are a subtype of EVs,and accumulating evidence indicates that adipose tissue exosomes(AT Exos)mediate crosstalk between adipose tissue and multiple organs by being transferred to targeted cells or tissues through paracrine or endocrine ***,the roles of AT Exos in crosstalk with metabolic organs remain to be fully *** this review,we summarize the latest research progress on the role of AT Exos in the regulation of metabolic ***,we discuss the potential role of AT Exos as biomarkers in metabolic diseases and their clinical application.

关键词： exosome adipose tissue obesity diabetes chronic metabolic disorder miRNA

Low-cycle fatigue behavior of solutionized and aged WE43 magnesium alloys at room temperature

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Journal of Magnesium and Alloys 2024年第6期12卷 2284-2297页

作者： yong Cai Jianxiong Wei Hong Yan Yipeng chen Rongshi chen School of Materials Science and Engineering University of Science and Technology of China72 Wenhua RoadShenyang 110016China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China School of Materials Science and Engineering Shandong University of Science and TechnologyQingdaoShandong 266590China

The low-cycle fatigue behavior of solutionized(T4)and aged(T6)WE43 magnesium alloys was studied at room *** total strain amplitudes(△ε_(t)/2)were 0.4%,0.5%,0.6%,0.7%and 1.0%.Detailed microstructure evolution was characterized by scanning electron microscope(SEM),electron backscattered diffraction(EBSD)and transmission electron microscopy(TEM).The results showed that plastic strain amplitude decreased with the increasing cycle number in T4 alloy,which is due to the dense persistent slip bands(PSBs)and dynamic precipitates hinderingdislocation *** contrast,the plastic strain amplitude increases gradually in T6 alloy,which is attributed to the enhanced activation of pyramidal *** low-cycle fatigue life of T6 alloy with larger fatigue ductility coefficient is longer than that of T4 *** Coffin-Manson model can accurately predict the fatigue life of T4 and T6 alloys compared to Jahed-Varvani(JV)energy *** T4 alloy,the fatigue damage mechanism was dominated by basal *** T6 alloy,the enhanced pyramidal slip plays an important role to accommodate plastic deformation.

关键词： Low-cycle fatigue WE43 alloy Cyclic hardening/softening JV model Dislocation