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Nonsmooth finite-time control of uncertain second-order nonlinear systems

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控制理论与应用（英文版） 2007年第2期5卷 171-176页

作者： Shuanghe yu zi MA Xiaohui yang Automation Research Center Dalian Maritime UniversityDalian Liaoning 116026 China

Nonsmooth finite-time stabilizing control laws have been developed for the double integrator system. The objective of this paper is to further explore the finite-time tracking control problem of a general form of uncertain secondorder affine nonlinear system with the new forms of terminal sliding mode （TSM）. Discontinuous and continuous finite-time controllers are also developed respectively without the singularity problem. Complete robustness can be acquired with the former, and enhanced robustness compared with the conventional boundary layer method can be expressed as explicit bounded function with the latter. Simulation results on the stabilizing and tracking problems are presented to demonstrate the effectiveness of the control algorithms.

关键词： Nonsmooth Finite-time stability Terminal sliding mode

Prototype of the readout electronics for the RICH PID detector in the STCF

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Nuclear Science and Techniques 2022年第6期33卷 148-160页

作者： Bao-Lin Hou Lei Zhao Jia-Jun Qin Ye-Qun Qi Jia-Ming Li zi-yu yang Shu-Bin Liu Qi An State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China School of Information Engineering Southwest University of Science and TechnologyMianyang 621010China

The ring imaging Cherenkov(RICH) detector for particle identification(PID) is being evaluated for the future super tau-charm facility(STCF) complex. In this work, the prototype readout electronics for the RICH PID detector is designed. The prototype RICH PID detector is based on a thick gas electron multiplier combined with a micromegas detector for Cherenkov light detection. Considering that there will be a large number(~ 690,000) of detector channels in future RICH detector, the readout electronics faces many challenges to precisely measuring time and charge information, such as reducing the noise,increasing density, and improving precision. The requirements of the readout electronics are explored, the downselection of the ASICs is made and thus a prototype readout electronics is designed and implemented. Tests are also conducted to evaluate the performance of the prototype readout electronics, and the results indicate that the time resolution is better than ~ 1 ns(RMS) when the input charge is greater than ~ 12 fC based on the APV25chip, while the time resolution is better than ~ 1 ns(RMS) at an input charge of over ~ 48 fC based on the AGET and STCF ASIC chips, and the equivalent noise charge is better than ~ 0.5 fC(RMS) @ 20 pF based on the three ASICs. The test results indicate that the prototype readout electronics design meets the requirement of the future RICH PID detector and thus provides a reference for future engineering.

关键词： Readout electronics Time measurement Charge measurement RICH PID detector STCF

Effect of cholesterol metabolism on hepatolithiasis

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World Journal of Gastroenterology 2025年第1期31卷 157-162页

作者： Lin Zheng zi-yu Ye Jun-Ji Ma Department of Gastroenterology The Second Hospital of Hebei Medical UniversityHebei Key Laboratory of GastroenterologyHebei Institute of GastroenterologyHebei Clinical Research Center for Digestive DiseasesNo.215 Heping West RoadShijiazhuang 050000Hebei ProvinceChina

Surgical intervention is currently the primary treatment for hepatolithiasis;how-ever,some patients still experience residual stones and high recurrence rates after *** metabolism seems to play an important role in hepatoli-thiasis pathogenesis.A high cholesterol diet is one of the significant reasons for the increasing incidence of ***,regular diet and appropriate medical intervention are crucial measures to prevent hepatolithiasis and reduce recurrence rate after *** dietary cholesterol and drugs that increase cholesterol stone solubility are key therapeutic approaches in treating *** article discusses the cholesterol metabolic pathways related to the pathogenesis of hepatolithiasis,as well as food intake and targeted therapeutic drugs.

关键词： Hepatolithiasis Cholesterol metabolism High-fat diet 3-hydroxy-3-methylglutaryl-coenzyme A reductase Interlobular bile duct

房地产市场的供给需求与税收政策调节作用分析

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维普期刊数据库

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北京工商大学学报（社会科学版） 2010年第3期25卷 58-62页

作者：吴荣胜于子洋中央财经大学财政学院北京100081

房价的不断上涨既有供给不足的原因也有需求旺盛的因素,遏制房价过快上涨必须针对不同类型的供需分层次调节。从我国房地产市场供给和需求的特点入手,从理论和政策层面分析了房价不断上涨的原因,并结合我国的实际情况对税收政策调节房... 详细信息

房价的不断上涨既有供给不足的原因也有需求旺盛的因素,遏制房价过快上涨必须针对不同类型的供需分层次调节。从我国房地产市场供给和需求的特点入手,从理论和政策层面分析了房价不断上涨的原因,并结合我国的实际情况对税收政策调节房地产市场的作用进行了评析。

关键词：房地产供给需求税收

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财政刺激政策的难题

中央财经大学学报 2010年第3期 7-10,16页

作者：于子洋曹静韬中央财经大学北京100081 首都经济贸易大学北京100026

在国际金融危机的影响下,许多国家采取加大财政支出的政策促进经济复苏。但是,这些财政刺激政策在现实中却遇到了一些难题:居民边际消费倾向的偏低、大国内的地区差异,以及财政年度平衡制度的弊端等。由于这些难题的存在,单纯依靠增加... 详细信息

在国际金融危机的影响下,许多国家采取加大财政支出的政策促进经济复苏。但是,这些财政刺激政策在现实中却遇到了一些难题:居民边际消费倾向的偏低、大国内的地区差异,以及财政年度平衡制度的弊端等。由于这些难题的存在,单纯依靠增加财政支出规模促进经济复苏的刺激政策的实施效果充满了不确定性。

关键词：财政支出刺激难题不确定性

Muon flux measurement at China Jinping Underground Laboratory

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Chinese Physics C 2021年第2期45卷 509-517页

作者： zi-yi Guo Lars Bathe-Peters Shao-min Chen Mourad Chouaki Wei Dou Lei Guo Ghulam Hussain Jin-jing Li Qian Liu Guang Luo Wen-tai Luo Ming Qi Wen-hui Shao Jian Tang Lin-yan Wan Zhe Wang Ben-da Xu Tong Xu Wei-ran Xu yu-zi yang Minfang Yeh Lin Zhao Department of Engineering Physics Tsinghua UniversityBeijing 100084China Center for High Energy Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle&Radiation Imaging(Tsinghua University) Ministry of EducationChina Institut für Physik Technische Universität BerlinBerlin 10623Germany École Polytechnique Fédérale de Lausanne Lausanne 1015Switzerland School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China School of Physics Sun Yat-Sen UniversityGuangzhou 510275China School of Physics Nanjing UniversityNanjing 210093China Brookhaven National Laboratory UptonNew York 11973USA

China Jinping Underground Laboratory(CJPL)is ideal for studying solar,geo-,and supernova neutrinos.A precise measurement of the cosmic-ray background is essential in proceeding with R&D research for these MeV-scale neutrino *** a 1-ton prototype detector for the Jinping Neutrino Experiment(JNE),we detected 264 high-energy muon events from a 645.2-day dataset from the first phase of CJPL(CJPL-I),reconstructed their directions,and measured the cosmic-ray muon flux to be (3.53±0.22_stat.±0.07_sys.)×-10^(-10)cm^(-2).The observed angular distributions indicate the leakage of cosmic-ray muon background and agree with simulation data accounting for Jinping mountain's terrain.A survey of muon fluxes at different laboratory locations,considering both those situated under mountains and those down mine shafts,indicates that the flux at the former is generally a factor of (4±2) larger than at the latter,with the same vertical *** study provides a convenient back-of-the-envelope estimation for the muon flux of an underground experiment.

关键词： CJPL cosmic-ray muon flux angular distribution neutrino detector liquid scintillator

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兰州市市区景观生态格局特征分析

甘肃农业大学学报 2012年第5期47卷 115-120页

作者：王录仓俞菲俞洋子西北师范大学地理与环境科学学院甘肃兰州730070

基于景观生态学理论,利用兰州市市区遥感影像数据和Fragstats软件,在GIS技术支持下,综合选取多样性、破碎度、均匀度、优势度、分离度等景观格局指数,从斑块格局、区域景观格局等方面进行景观生态研究.结果表明:兰州市市区林草地占总面... 详细信息

基于景观生态学理论,利用兰州市市区遥感影像数据和Fragstats软件,在GIS技术支持下,综合选取多样性、破碎度、均匀度、优势度、分离度等景观格局指数,从斑块格局、区域景观格局等方面进行景观生态研究.结果表明:兰州市市区林草地占总面积的45%,构成区域景观的基质;区域内景观多样性分布具有较好的空间结构,多样性指数城关区最高为1.447,均匀度七里河区最高为0.811;区域中人工景观斑块形状规则,分布均匀,自然景观分维数较高,其中荒草地分维数1.443;受人为影响,农业景观类型破碎度较高,大量耕地转变为建设用地和林地;城市人均绿地9.47m2,但绿地斑块分布散乱,生态效益低;各类型绿地斑块之间缺少较好的生态廊道,格局连接性较低;分离度城关区为0.015、七里河区为0.045、西固区0.037、安宁区为0.021.

关键词：景观生态格局斑块分维数多样性兰州市

铅酸蓄电池铝基板栅表面镀层的电化学性能研究

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电源技术 2008年第4期32卷 233-235页

作者：于紫阳徐强唐致远天津大学化工学院应用化学系天津300072

研究了铅酸蓄电池铝基轻型板栅表面涂层的电化学性能。通过电沉积的方法在铝合金基体上制备出不同锡含量的铅锡镀层,利用线性扫描、交流阻抗等电化学方法分析了铅锡镀层的耐腐蚀性能、析气性能及其镀层在0.9V(***/Hg2SO4)阳极氧化一定... 详细信息

研究了铅酸蓄电池铝基轻型板栅表面涂层的电化学性能。通过电沉积的方法在铝合金基体上制备出不同锡含量的铅锡镀层,利用线性扫描、交流阻抗等电化学方法分析了铅锡镀层的耐腐蚀性能、析气性能及其镀层在0.9V(***/Hg2SO4)阳极氧化一定时间后的特性。实验结果表明,铅锡镀层中锡含量为2.0%左右时,不但具有较好的耐蚀性能,而且有效降低了阳极膜的阻抗,减轻电池深充放时正极板栅的钝化现象,有利于延长电池的使用寿命。锡含量为0.67%时的铅锡镀层作为负极板栅表面涂层,具有较高的析氢过电位和较好的耐蚀性能。

关键词：轻型板栅铅锡镀层线性扫描交流阻抗阳极膜

不同城市居民头发中氧、氢稳定同位素检验和特征初探

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生物化学与生物物理进展 2022年第12期49卷 2410-2420页

作者：于子洋杨瑞琴黄阳秦皓胡灿朱军王萍郭洪玲梅宏成中国人民公安大学侦查学院北京100038 公安部物证鉴定中心北京100038

目的人体组织的稳定同位素组成与其生长期间的个体饮食情况、所处环境及代谢状况有关。人头发一经长出便不再与身体进行物质交换,化学性质稳定,易于采集,是研究人体组织稳定同位素组成的良好对象。构成人体的氧、氢元素主要来自于所摄... 详细信息

目的人体组织的稳定同位素组成与其生长期间的个体饮食情况、所处环境及代谢状况有关。人头发一经长出便不再与身体进行物质交换,化学性质稳定,易于采集,是研究人体组织稳定同位素组成的良好对象。构成人体的氧、氢元素主要来自于所摄入的水和食物,其中氧、氢稳定同位素组成会通过角蛋白的形式被记录于头发当中。不同地区居民头发中氧、氢稳定同位素组成差异可被用于推断人的饮食情况、生活地域和活动轨迹信息,在法庭科学等研究领域具有重要意义。方法本研究利用元素分析仪-稳定同位素比质谱仪(EA-IRMS)对国内不同地区常住居民头发样本进行氧、氢稳定同位素比值检测和分析。结果部分城市间居民头发δ^(18)O和δ^(2)H存在显著性差异,整体δ^(18)O和δ^(2)H存在显著正相关性。对所得稳定同位素数据进行判别分析推断头发的地域来源,其交互验证整体判别准确率为63.9%,结合碳、氮稳定同位素数据后,其判别准确率大幅提升,交互验证的整体判别准确率达到76.0%。随着判别分析中使用的稳定同位素种类的增加,判别函数模型的判别能力明显增强。结论利用4种元素稳定同位素数据建立的多层感知器神经网络模型的整体判别准确率为82.8%,径向基函数神经网络模型整体判别准确率为78.8%,3种溯源推断数学模型中,多层感知器神经网络模型的判别准确率最高。

关键词：人头发氧、氢稳定同位素溯源推断