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与GH凸函数有关的若干积分不等式

首都师范大学学报（自然科学版） 2016年第3期37卷 1-3页

作者：时统业李照顺秦华海军指挥学院信息系江苏南京211800

利用GH凸函数与GA凸函数的关系,证明了GH凸函数存在单侧导数,并通过不等式建立了GH凸函数与其单侧导数的联系.用普通数学分析的方法建立了若干GH凸函数的不等式.

关键词： GH凸函数积分不等式单侧导数

基于CPN Tools的航母编队远程协同防空指挥控制模型研究

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舰船电子工程 2016年第2期36卷 1-4,30页

作者：赵秦豫李照顺蓝湾湾吴琦海军指挥学院南京211800

针对航母编队远程防空问题,分析了预警机协同舰载机进行远程防空作战指挥控制过程,并运用CPN Tools仿真平台建立了航母编队远程协同防空作战中的相关指挥控制模型,包括顶层模型、目标模型、防空响应模型、预警机探测引导模型、编队指挥... 详细信息

针对航母编队远程防空问题,分析了预警机协同舰载机进行远程防空作战指挥控制过程,并运用CPN Tools仿真平台建立了航母编队远程协同防空作战中的相关指挥控制模型,包括顶层模型、目标模型、防空响应模型、预警机探测引导模型、编队指挥所指挥控制模型和舰载机模型,为航母编队远程协同防空作战指挥控制动态仿真分析奠定了基础。

关键词：航母编队协同防空指挥控制 CPN Tools

Boosting hydrogen storage performance in COF-108 by single-walled carbon nanotube insertion, boron substitution,and lithium doping at room temperature

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Science China Technological Sciences 2024年第12期67卷 3791-3800页

作者： MENG zhaoshun MA HongYan WANG Qing YANG Xiao WANG YunHui li XingAo Jiangsu Provincial Engineering Research Center of Low-Dimensional Physics and New Energy & College of Science Nanjing University of Posts and Telecommunications

A novel hybrid material based on covalent organic frameworks（COFs） was proposed for highly efficient hydrogen（H2） storage at room temperature. Single-walled carbon nanotubes（SWNTs） were inserted into COF-108, and additional lithium（li） atoms were doped into the boron-substituted structures. Density functional theory calculations were used to determine the optimized hybrid structures and the reasonable force field parameters between the hydrogen in H2and the elements in the sorbent. In addition, H2adsorption simulations via the grand canonical Monte Carlo approach revealed that SWNT insertion and li doping substantially elevated the room-temperature H2storage performance. A detailed analysis was provided on the impact of the number of doped li atoms and the specific surface area on H2uptake. The highest excess gravimetric and volumetric H2uptake values were 5.08 wt% and 31.65 g/L, respectively, for li-doped B-substituted SWNT（15,0）@COF-108 and SWNT（9,9）@COF-108 at 298 K and 100 bar. Surprisingly, the total H2uptake of li-doped B-substituted SWNT（9,9）@COF-108 not only met but also surpassed the 2020 target of the U.S. Department of Energy（DOE） within the temperature and pressure limits of the *** study presents a theoretically grounded, multiple modification strategy for the design of porous materials with exceptional H2storage capabilities, offering a promising avenue for the development of advanced H2storage solutions.

关键词： hydrogen storage COF-108 single-walled carbon nanotube insertion boron substitution lithium doping density functional theory calculation grand canonical Monte Carlo simulation

Measurement of Mean Burst Period in WallTurbulence by Wavelet Analysis

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Communications in Nonlinear Science and Numerical Simulation 1999年第3期4卷 3-5页

作者： li li Chunxiao XU zhaoshun ZHANG and Guialang CUI(Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China) Department of Engineering Mechanics Tsinghua University Beijing 100084 China

IntroductionInwallturbulence,theejectionoflow-speedfluidfromthewallandthesweepofth***urst,andwhentheflowisbursting,therealwaysea... 详细信息

IntroductionInwallturbulence,theejectionoflow-speedfluidfromthewallandthesweepofth***urst,andwhentheflowisbursting,therealwaysea...

关键词： turbulence burst phenomena wavelet analysis

Study on near-wall turbulence structures with local Reynolds stress

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Communications in Nonlinear Science and Numerical Simulation 2000年第3期5卷 105-117页

作者： li li Chunxiao XU Guixiang CUI and zhaoshun ZHANG(Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China) Department of Engineering Mechanics Tsinghua University Beijing 100084 China

The direct- numerical- simulated ch annel turbulence is analyzed with two-dimensional wavelet transform. Considering the relation between turbulence coherent structure and Reynolds stress in near wall region, the local Reynolds stress (LRS) is defined.A new method for extracting coherent signals from turbulence based on the LRS is developed. Velocity fiuctuations are decomposed to coherent signals and background signals. It is found that the scaling exponents of coherent signals have a considerable deviation from the Kolmogorov scaling law q/3 (K41 theory), while that of background signals is very close to q/3. It is confirmed that coherent signals are mainly responsible for the anomalous *** characterized by the positive peaks of LRS, the typical structures in near wall region are obtained by conditional statistical averaging. It is shown that the local character of near-wall turbulence structures can be effectively described with LRS.

关键词： wavelet channel turbulence the local Reynolds stress

Large eddy simulation of stably stratified turbulence

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Science China(Physics,Mechanics & Astronomy) 2010年第1期53卷 135-146页

作者： SHEN Zhi, li YuPeng, CUI GuiXiang & ZHANG zhaoshun Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China 1. Department of Engineering Mechanics Tsinghua University Beijing 100084 China

Stable stratification turbulence, as a common phenomenon in atmospheric and oceanic flows, is an important mechanism for numerical prediction of such flows. In this paper the large eddy simulation is utilized for investigating stable stratification turbulence numerically. The paper is expected to provide correct statistical results in agreement with those measured in the atmosphere or ocean. The fully developed turbulence is obtained in the stable stratification fluid by large eddy simulation with different initial velocity field and characteristic parameters, i.e. Reynolds number Re and Froude number Fr. The evolution of turbulent kinetic energy, characteristic length scales and parameters is analyzed for investigating the development of turbulence in stable stratification fluid. The three-dimensional energy spectra, horizontal and vertical energy spectrum, are compared between numerical simulation and real observation in the atmosphere and ocean in order to test the reliability of the numerical simulation. The results of numerical cases show that the large eddy simulation is capable of predicting the properties of stable stratification turbulence in consistence with real measurements at less computational cost. It has been found in this paper that the turbulence can be developed under different initial velocity conditions and the internal wave energy is dominant in the developed stable stratification turbulence. It is also found that the characteristic parameters must satisfy certain conditions in order to have correct statistical property of stable stratification turbulence in the atmosphere and ocean. The Reynolds number and Froude number are unnecessarily equal to those in atmosphere or ocean, but the Reynolds number must be large enough, say, greater than 10 2 , and Froude number must be less than 0.1. The most important parameter is ReFr 2 which must be greater than 10.

关键词： stratified turbulence internal wave potential vortex large eddy simulation

Investigation on the Novel High-performance Copper/Graphene Composite Conductor for High Power Density Motor

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CES Transactions on Electrical Machines and Systems 2024年第1期8卷 80-85页

作者： Jiaxiao Wang Tingting Zuo Jiangli Xue Yadong Ru Yue Wu Zhuang Xu Yongsheng liu zhaoshun Gao Puqi Ning Tao Fan Xuhui Wen li Han liye Xiao Shanghai University of Electric Power Shanghai 200090Chinaand the Institute of Electrical EngineeringChinese Academy of SciencesShanghai 200090China the Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China with Shanghai University of Electric Power Shanghai 200090China

High-performance Cu/Graphene composite wire synergistically strengthened by nano Cr_(3)C_(2) phase was directly synthesized via hot press sintering followed by severe cold plastic deformation, using liquid paraffin and CuCr alloy powder as the raw materials. Since graphene is in situ formed under the catalysis of copper powder during the sintering process, the problem that graphene is easy to agglomerate and difficult to disperse uniformly in the copper matrix has been solved. The nano Cr_(3)C_(2)-particles nailed at the interface favor to improve the interface bonding. The Cu/Graphene composite possesses high electrical conductivity, hardness, and plasticity. The composite wire exhibits high electrical conductivity of 96.93% IACS, great tensile strength of 488MPa, and excellent resistance to softening. Even after annealing at 400℃ for 1 h, the tensile strength can still reach 268 MPa with a conductivity of about 99.14% *** wire's temperature coefficient of resistance(TCR) is largely reduced to 0.0035/℃ due to the complex structure,which leads the wire to present low resistivity at higher temperatures. Such Cu/Graphene composite wire with excellent comprehensive performance has a good application prospect in high-power density motors.

关键词： Cu/Graphene composite Mechanical properties Electrical property Microstructure Temperature coefficient of resistance

The involvement of Slc7a11/xCT related iron accumulation on acupuncture intervention in 6-OHDA-induced Parkinson rat

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Clinical Traditional Medicine and Pharmacology 2024年第4期5卷 34-43页

作者： lihong li Wei Jin Jun Lu Zitong Xu zhaoshun Lv Jianquan Yin Wenjie Cong Acupuncture Department The Second Affiliated Hospital of Zhejiang Chinese Medical University(Xinhua Hospital of Zhejiang Province)Hangzhou 310005ZhejiangChina The First School of Clinical Medicine Zhejiang Chinese Medical UniversityHangzhou 310053ZhejiangChina Urological Department Zitong Hospital of Traditional Chinese MedicineMianyang 622150SichuanChina The Second School of Clinical Medicine Zhejiang Chinese Medical UniversityHangzhou 310053ZhejiangChina Acupuncture Department Zhejiang Provincial People’s HospitalHangzhou 310004ZhejiangChina Acupuncture and Physiotherapy Department The First Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325015ZhejiangChina

Background:Acupuncture plays a critical role for the treatment of patients with Parkinson’s disease(PD),which is characterized by ferroptosis of dopaminergic *** has been found that acupuncture can reduce iron ***,the mechanism of acupuncture therapy against PD by inhibiting ferroptosis remains ***:To investigate the potential mechanism of acupuncture on alleviating ferroptosis in 6-OHDA-induced PD ***:Male Sprague-Dawley rats were randomly divided into sham group,acupuncture group,and PD model group,with the PD model induced by *** motor function of the rats was tested by the rotation test and suspension test,*** and iron staining were performed to analyze nerve damage,and the effect of acupuncture on the accumulation of iron in the substantia nigra(SN).RNA-seq analysis in the SN of rats were performed to discover ferroptosis-related *** expressed genes(DEGs)resulted from the acupuncture treatment were identified and were used for Gene Ontology(GO)function,Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analyses.A protein–protein interaction(PPI)network was constructed,and alternative splicing(AS)analysis of the transcriptome was *** blot was used to detect the protein level change of Slc7a11/***:Rotation test and suspension test indicated a positive effect of acupuncture on body weight gain and limb ***’s iron staining and EliSA test detected 6-OHDA induced iron accumulation in the SN and nerve damage,which was mitigated by acupuncture *** treatment brought about the differential expression of a total of 1088 genes in the SN of *** and KEGG enrichment revealed that such DEGs were mainly associated with several key biological process(BP),cellular component(CC)and molecular function(MF)*** terms included collagen fibril organization,extracellular matrix organization,collagen trimer,extracel

关键词： Parkinson’s disease RNA-seq Slc7a11/xCT Acupuncture

改进的变步长自适应最小均方算法及其数字信号处理

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强激光与粒子束 2015年第9期27卷 39-43页

作者：吕照顺吴晗平李军雨海军工程大学兵器工程系武汉430033 武汉工程大学光电子系统技术研究所武汉430205 湘潭大学物理与光电工程学院湖南湘潭411105

针对紫外光通信中传统自适应最小均方(LMS)算法存在的不足,提出了一种新的变步长LMS(VSS-LMS)算法,利用MATLAB仿真验证了该算法的可行性,以TMS320VC5509为核心设计了数字信号处理(DSP)最小化硬件系统和VSS-LMS算法的软件流程,在硬件上... 详细信息

针对紫外光通信中传统自适应最小均方(LMS)算法存在的不足,提出了一种新的变步长LMS(VSS-LMS)算法,利用MATLAB仿真验证了该算法的可行性,以TMS320VC5509为核心设计了数字信号处理(DSP)最小化硬件系统和VSS-LMS算法的软件流程,在硬件上实现了传统LMS算法和新的VSS-LMS算法的自适应滤波,并进行了对比分析,结果表明所提出的VSS-LMS算法具有较快的收敛速度和较小的稳态误差,这对紫外光通信接收系统的设计和优化具有一定的参考意义。

关键词：紫外光通信最小均方算法变步长最小均方算法数字信号处理