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Journal of Modern Transportation 1997年第1期14卷 37-44页

作者： chen yong yan jing school of mechanical engineering, southwest jiaotong university, chengdu 610031, china

A new iterating method based on homotopy function is developed in this paper. All solutions can be found easily without the need of choosing proper initial values. Compared to the homotopy continuation method, the solution process of the present method is simplified, and the computation efficiency as well as the reliability for obtaining all solutions is also improved. By application of the method to the mechanisms problems, the results are satisfactory.

关键词： numerical iteration method homotopy iteration algorithm polynomial systems kinematic analysis and synthesis of mechanisms

Clinical manifestation,lifestyle,and treatment patterns of chronic erosive gastritis:A multicenter real-world study in china

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World Journal of Gastroenterology 2024年第9期30卷 1108-1120页

作者： Ying-Yun yang Ke-Min Li Gui-Fang Xu cheng-Dang Wang Hua Xiong Xiao-Zhong Wang Chun-Hui Wang Bing-yong Zhang Hai-Xing Jiang jing Sun yan Xu Li-Juan Zhang Hao-Xuan Zheng Xiang-Bin Xing Liang-jing Wang Xiu-Li Zuo Shi-Gang Ding Rong Lin Chun-Xiao chen Xing-Wei Wang jing-Nan Li Department of Gastroenterology Peking Union Medical College HospitalPeking Union Medical CollegeChinese Academy of Medical SciencesBeijing 100730China Department of Gastroenterology Nanjing Drum Tower HospitalNanjing 21000Jiangsu ProvinceChina Department of Gastroenterology The First Affiliated Hospital of Fujian Medical UniversityFuzhou 350005Fujian ProvinceChina Department of Gastroenterology Renji HospitalShanghai 200127China Department of Gastroenterology Union Hospital of Fujian Medical UniversityFuzhou 350000Fujian ProvinceChina Department of Gastroenterology West China Hospital of Sichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Gastroenterology and Hepatology The People’s Hospital of Zhengzhou UniversityThe Henan Provincial People’s HospitalZhengzhou 450003Henan ProvinceChina Department of Gastroenterology The First Affiliated Hospital of Guangxi Medical UniversityNanning 530021Guangxi Zhuang Autonomous RegionChina Ruijin Hospital Shanghai jiaotong university school of Medicine Shanghai Jiao Tong UnivesrityRuijin HospitalSchool MedicineShanghai 200025China Department of Gastroenterology and Hepatology China-Japan Union Hospital of Jilin UniversityChangchun 130033Jilin ProvinceChina Department of Gastroenterology Fujian Medical University Union HospitalFuzhou 350001Fujian ProvinceChina Department of Gastroenterology Nanfang HospitalGuangzhou 510080Guangdong ProvinceChina Department of Gastroenterology The First Affiliated HospitalSun Yat-sen UniversityGuangzhou 510080Guangdong ProvinceChina Department of Gastroenterology The Second Affiliated Hospital Zhejiang University School of MedicineHangzhou 310000Zhejiang ProvinceChina Department of Gastroenterology Shandong University Qilu HospitalJinan 250012Shandong ProvinceChina Department of Gastroenterology Peking University Third HospitalBeijing 100191China Department of Gastroenterology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022Hubei Pr

BACKGROUND Although chronic erosive gastritis(CEG)is common,its clinical characteristics have not been fully *** lack of consensus regarding its treatment has resulted in varied treatment *** To explore the clinical characteristics,treatment patterns,and short-term outcomes in CEG patients in *** We recruited patients with chronic non-atrophic or mild-to-moderate atrophic gastritis with erosion based on endoscopy and *** and treating physicians completed a questionnaire regarding history,endoscopic findings,and treatment plans as well as a follow-up questionnaire to investigate changes in symptoms after 4 wk of *** Three thousand five hundred sixty-three patients from 42 centers across 24 cities in china were *** pain(68.0%),abdominal distension(62.6%),and postprandial fullness(47.5%)were the most common presenting *** was classified as chronic non-atrophic in 69.9%of *** those with erosive lesions,72.1%of patients had lesions in the antrum,51.0%had multiple lesions,and 67.3%had superficial flat *** patients with epigastric pain,the combination of a mucosal protective agent(MPA)and proton pump inhibitor was more *** those with postprandial fullness,acid regurgitation,early satiety,or nausea,a MPA appeared more *** CEG is a multifactorial disease which is common in Asian patients and has non-specific *** may play a major role in its detection and *** should be individualized based on symptom profile.

关键词： Chronic erosive gastritis Symptom Endoscopic findings Treatment pattern Real-world

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一种基于同伦函数的迭代法──同伦迭代法

数值计算与计算机应用 2001年第2期22卷 149-155页

作者：陈永李立张剑严静西南交通大学机械工程学院

Based on the homotopy function, a new iterative algorithm for solving nonlinear polynomial systems called homotopy iteration method has been developed. All solutions can be found easily without the need of choosing proper initial values. Compared to the homotopy continuation method, the solution process of the present method is much simplified, and the computation efficiency as well as the reliability for obtaining all solutions are also improved. Applicating the method to a number of problems coming from engineering, the results are satisfactory.

关键词：数值迭代法同伦迭代法同伦函数多项式方程组映射零点数值求解

D2- like but not D1- like dopamine receptors in ventrolateral orbital cortex are involved in apomorphine-induced antiallodynia in a neuropathic pain model of rats

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D2- like but not D1- like dopamine receptors in ventrolatera...

Insight into the Excellent Tribological Performance of Highly Oriented Poly(phenylene sulfide)

中国神经科学学会第四次会员代表大会暨第八届全国学术会议

作者： yong-Hui DANG~1,yan ZHAO~1,Bo XING~1,Xiao-Jie ZHAO~1,Teng chen~1,jing-Shi TANG~2,Fu-Quan HUO~2,Feng-Yi XU~2, Chao-LingQU~(2,*) 1 Department of Forensic Medicine,Key Laboratory of Environment and Gene Related to Diseases,Ministry of Education, Xi''an jiaotong university school of Medicine,Xi''an 710061,china 2 Department of Physiology and Pathophysiology,Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education,Xi''an jiaotong university school of Medicine,Xi''an 710061,china

＜正＞Objective The ventrolateral orbital cortex（VLO） is part of an endogenous analgesic system consisting of an ascending pathway from the spinal cord to VLO via the thalamic nucleus submedius（Sm） and a descending pathway to the spinal cord relaying in the periaqueductal gray（PAG）.The aim of the present study was to examine whether dopamine and its receptors are involved in the antinociception in *** The animal model of persistent peripheral neuropathic pain-spared nerve injury（SNI） was *** withdrawal threshold in response to von-Frey hair stimulation of the injury side hindpaw was measured as an index of mechanical ***（1） Microinjection of the nonselective dopamine receptor agonist apomorphine（1.0,2.5,5.0μg in 0.5μl） into the VLO significantly increased the paw withdrawal threshold in a dose-dependent manner,which was reversed by pretreatment with selective D2-like dopamine receptor antagonist raclopride（1.5μg in 0.5μl）,but not selective D1-like dopamine receptor antagonist（SCH23390 5.0μg in 0.5μl）.（2） Microinjection of raclopride or SCH23390 alone into the VLO had no effects on mechanical paw withdrawal threshold. Conclusion The results suggest that dopamine neurotransmitter is involved in VLO-induced anti-allodynia,and this effect is mediated by D2-like but not Dl-like dopamine receptors.

关键词： ventrolateral orbital cortex dopamine receptor raclopride SCH23390 mechanical allodynia spared nerve injury rat

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Chinese Journal of Polymer Science 2022年第3期40卷 290-298,I0007页

作者： Liang-Qing Zhang Shu-Gui yang jing-Han Zhang Ke-Peng Zhong Zhong-Guo Zhao yan-Hui chen Jun Lei Qiu-Yu Zhang Zhong-Ming Li College of Material Science and engineering Xi’an University of Science and TechnologyXi’an 710054China State Key Laboratory for mechanical Behaviour of Materials Shaanxi International Research Center for Soft MaterialsXi’an Jiaotong UniversityXi’an 710049China school of Chemistry and Chemical engineering Shaanxi Key Laboratory of Macromolecular Science and TechnologyKey Laboratory of Special Functional and Smart Polymer Materials of Ministry of Industry and Information TechnologyNorthwestern Polytechnical UniversityXi’an 710072China National and Local engineering Laboratory for Slag Comprehensive Utilization and Environment Technology School of Materials Science and EngineeringShaanxi University of TechnologyHanzhong 723000China College of Polymer Science and engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China

Achieving low friction and wear of poly(phenylene sulfide)(PPS) without using fillers or blending is a challenging task, but one of considerable practical importance. Here we describe how neat PPS with high tribological performance is achieved by manipulating processing parameters(pressure, flow and temperature). The key to achieving high tribological performance is comparatively high molecular chain orientation, realized in neat PPS, at high shear rates and low pressure. The friction coefficient and wear rate are as low as ~0.3 and~10^(-6) mm^(3)·N^(-1)·m^(-1), respectively, which break the record for neat PPS. These values are even better than those for PPS-based blends and comparable to PPS composites. Further studies show, for the first time, that wear rate decreases exponentially with increasing molecular chain orientation, prompting us to revise the classical Archard's law by including the effect of molecular chain orientation. These findings open the possibility of using neat PPS in highly demanding tribological applications.

关键词： Poly(phenylene sulfide) Orientation Wear rate Frication coefficient Processing parameters

CEPC Technical Design Report

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Radiation Detection Technology and Methods 2024年第1期8卷 I0003-I0016,1-1091页

作者： Waleed Abdallah Tiago Carlos Adorno de Freitas Konstantin Afanaciev Shakeel Ahmad Ijaz Ahmed Xiaocong Ai Abid Aleem Wolfgang Altmannshofer Fabio Alves Weiming An Rui An Daniele Paolo Anderle Stefan Antusch Yasuo Arai Andrej Arbuzov Abdesslam Arhrib Mustafa Ashry Sha Bai Yu Bai yang Bai Vipul Bairathi Csaba Balazs Philip Bambade yong Ban Tripamo Bandyopadhyay Shou-Shan Bao Desmond P.Barber Ayse Bat Varvara Batozskaya Subash Chandra Behera Alexander Belyaev Michele Bertucci Xiao-Jun Bi Yuanjie Bi Tianjian Bian Fabrizio Bianchi Thomas Biekotter Michela Biglietti Shalva Bilanishvili Deng Binglin Denis Bodrov Anton Bogomyagkov Serge Bondarenko Stewart Boogert Maarten Boonekamp Marcello Borri Angelo Bosotti Vincent Boudry Mohammed Boukidi Igor Boyko Ivanka Bozovic Giuseppe Bozzi Jean-Claude Brient Anastasiia Budzinskaya Masroor Bukhari Vladimir Bytev Giacomo Cacciapaglia Hua Cai Wenyong Cai Wujun Cai Yijian Cai Yizhou Cai Yuchen Cai Haiying Cai Huacheng Cai Lorenzo Calibbi Junsong Cang Guofu Cao Jianshe Cao Antoine Chance Xuejun Chang Yue Chang Zhe Chang Xinyuan Chang Wei Chao Auttakit Chatrabhuti Yimin Che Yuzhi Che Bin chen Danping chen Fuqing chen Fusan chen Gang chen Guoming chen Hua-Xing chen Huirun chen Jinhui chen Ji-Yuan chen Kai chen Mali chen Mingjun chen Mingshui chen Ning chen Shanhong chen Shanzhen chen Shao-Long chen Shaomin chen Shiqiang chen Tianlu chen Wei chen Xiang chen Xiaoyu chen Xin chen Xun chen Xurong chen Ye chen Ying chen Yukai chen Zelin chen Zilin chen Gang chen Boping chen Chunhui chen Hok Chuen cheng Huajie cheng Shan cheng Tongguang cheng Yunlong Chi Pietro Chimenti Wen Han Chiu Guk Cho Ming-Chung Chu Xiaotong Chu Ziliang Chu Guglielmo Coloretti Andreas Crivellin Hanhua Cui Xiaohao Cui Zhaoyuan Cui Brunella D'Anzi Ling-Yun Dai Xinchen Dai Xuwen Dai Antonio De Maria Nicola De Filippis Christophe De La Taille Francesca De Mori Chiara De Sio Elisa Del Core Shuangxue Deng Wei-Tian Deng Zhi Deng Ziyan Deng Bhupal Dev Tang Dewen Biagio Di Micco Ran Ding Siqin Dingl Yadong Ding Haiyi Dong Jianin AGH university of Science and Technology Faculty of Physics and Applied Computer ScienceKrakow Anhui university HefeiAnhui Applied Physics Department Federal Urdu University of ArtsScience and TechnologyIslamabad Banaras Hindu university Institute of ScienceVaranasi Bandirma Onyedi Eylul university Bandirma Beihang university Beijing Beijing Computational Science Research Center Beijing Beijing Conveyi LTD Beijing Beijing Glass Research Institute Co. LtdBeijing Beijing Institute of Technology Beijing Beijing Normal university Beijing Brown university ProvidenceRI Budker Institute of Nuclear Physics Novosibirsk Cadi Ayyad university Laboratory of Fundamental and Applied PhysicsPolydisciplinary FacultyMarrakech Cairo university Giza Center for Theory and Computation National Tsing Hua UniversityHsinchu Central china Normal university WuhanHubei Central South university ChangshaHunan Centro de Fisica Teorica de Particulas Universidade Tecnica de LisboaLisboa chengdu KaitengSifang Digital Radio&TV Equipment Co. LtdChengduSichuan china academy of engineering physics MianyangSichuan china building materials academy Beijing china Center of Advanced Science and Technology Beijing china Institute of Atomic Energy Beijing china Jiliang university HangzhouZhejiang china Nuclear Instrument CO. LTDBeijing china university of Geosciences Beijing china university of Geosciences WuhanHubei china university of Mining and Technology XuzhouJiangsu china West Normal university NanchongSichuan Chongqing university Department of PhysicsChongqing Chulalongkorn university Bangkok City university of Hong Kong Department of PhysicsHong Kong Cockcroft Institute Daresbury Cornell university IthacaNY CPPM(AMU/IPhU&CNRS/INP) Marseille Dalian Minzu university DalianLiaoning Dalian university of Technology Department of PhysicsDalian Deutsches Elektronen-Synchrotron DESY Hamburg Dzhelepov Laboratory of Nuclear Problems of Joint Institute for Nuclear Research(DLNP JINR) Dubna East china university Of Science And Technol

The Circular Electron Positron Collider(CEPC)is a large scientific project initiated and hosted by china,fostered through extensive collaboration with international *** complex comprises four accelerators:a 30 GeV Linac,a 1.1 GeV Damping Ring,a Booster capable of achieving energies up to 180 GeV,and a Collider operating at varying energy modes(Z,W,H,and tt).The Linac and Damping Ring are situated on the surface,while the subterranean Booster and Collider are housed in a 100 km circumference underground tunnel,strategically accommodating future expansion with provisions for a potential Super Proton Proton Collider(SPPC).The CEPC primarily serves as a Higgs *** its baseline design with synchrotron radiation(SR)power of 30 MW per beam,it can achieve a luminosity of 5×10^(34)cm^(-2)s^(-1)per interaction point(IP),resulting in an integrated luminosity of 13 ab^(-1)for two IPs over a decade,producing 2.6 million Higgs *** the SR power to 50 MW per beam expands the CEPC's capability to generate 4.3 million Higgs bosons,facilitating precise measurements of Higgs coupling at sub-percent levels,exceeding the precision expected from the HL-LHC by an order of *** Technical Design Report(TDR)follows the Preliminary Conceptual Design Report(Pre-CDR,2015)and the Conceptual Design Report(CDR,2018),comprehensively detailing the machine's layout,performance metrics,physical design and analysis,technical systems design,R&D and prototyping efforts,and associated civil engineering ***,it includes a cost estimate and a preliminary construction timeline,establishing a framework for forthcoming engineering design phase and site selection *** is anticipated to begin around 2027-2028,pending government approval,with an estimated duration of 8 *** commencement of experiments and data collection could potentially be initiated in the mid-2030s.

关键词： initiated exceeding precise

高功率脉冲磁控溅射钛靶材的放电模型及等离子特性

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物理学报 2021年第18期70卷 65-74页

作者：陈畅子马东林李延涛冷永祥西南交通大学材料科学与工程学院材料先进技术教育部重点实验室成都610031 荆楚理工学院机械工程学院荆门448000

等离子密度及金属离化率是影响高功率脉冲磁控溅射沉积薄膜质量的关键因素,高功率脉冲磁控溅射参数(如电压、脉宽、沉积气压及峰值电流等)影响着等离子密度和金属离化率.本文利用MATLAB/SIMULINK建立等效电路模型,对高功率脉冲磁控溅射... 详细信息

等离子密度及金属离化率是影响高功率脉冲磁控溅射沉积薄膜质量的关键因素,高功率脉冲磁控溅射参数(如电压、脉宽、沉积气压及峰值电流等)影响着等离子密度和金属离化率.本文利用MATLAB/SIMULINK建立等效电路模型,对高功率脉冲磁控溅射钛(Ti)靶材的放电电流曲线进行模拟,利用鞘层电阻计算Ti靶材鞘层处的等离子密度,并采用半圆柱体-整体模型理论计算Ti的离化率.研究发现:采用由电容、电感和电阻组成的等效电路模型,可以模拟Ti靶材的放电电流;在不同高功率脉冲溅射电压、脉冲宽度和不同沉积气压下,真空室等离子密度在2×10^(17)-9×10^(17)m^(-3)范围内,随着溅射电压、脉冲宽度及沉积气压的增加,鞘层处的平均等离子密度增大;在不同沉积气压下,Ti的离化率值在31%-38%之间,随着气压增加,Ti的离化率增加.

关键词：高功率脉冲磁控溅射等效电路整体模型离化率

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子系统参数对双层隔振系统隔振特性的影响

交通运输工程学报 2018年第3期18卷 114-128页

作者：陈俊丁杰闫兵王永胜董大伟华春蓉株洲中车时代电气股份有限公司湖南株洲412000 西南交通大学机械工程学院四川成都610031 西南交通大学牵引动力国家重点实验室四川成都610031

为了阐明子系统参数对双层隔振系统隔振特性的影响,建立了针对带子系统的双层隔振系统的三自由度动力学模型;推导了一、二级主系统与子系统振幅比的解析式;分析了3种振幅比随子系统质量比、固有频率比和阻尼比的变化规律;给出了子系统... 详细信息

为了阐明子系统参数对双层隔振系统隔振特性的影响,建立了针对带子系统的双层隔振系统的三自由度动力学模型;推导了一、二级主系统与子系统振幅比的解析式;分析了3种振幅比随子系统质量比、固有频率比和阻尼比的变化规律;给出了子系统充当双层隔振系统吸振器时最优参数的解析解和数值精确解;以中国首批内燃动车动力包为研究对象,探讨了散热器子系统的刚度、阻尼和质量对动力包双层隔振系统隔振性能以及柴油发电机组和散热器本身振动烈度的影响规律;得到了最优散热器隔振器刚度的动力包双层隔振系统样机,并进行了振动试验。试验结果表明:散热器隔振器刚度大于拐点处刚度1.5倍会严重恶化子系统的振动情况,其阻尼损耗系数取0.24左右能有效抑制双层隔振系统力传递率和振动烈度比的峰值,取较大的散热器质量能有效提高双层隔振系统的隔振性能,减小机组和散热器本身的振动烈度;经过设计后,停机工况下二级隔振器最大动反力减小50%,常规工况下二级隔振器的实测最大动反力为296N,优于同类水平,常规工况下机组与散热器实测振动烈度最大值分别为15.45、4.97mm·s-1,水平优秀。可见,取较大的子系统质量和阻尼,并将其视为双层隔振系统的吸振器进行优化设计,可使双层隔振系统在柴油机启停机工况和常规工况下都具备较优的动力学性能。

关键词：车辆工程子系统双层隔振系统隔振特性动力包吸振器

轨道非平稳不平顺激扰下高速列车半主动控制研究

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机械设计与制造 2019年第2期 26-29,33页

作者：闫中奎陈春俊熊仕勇西南交通大学机械工程学院四川成都610031

为改善轨道非平稳随机不平顺对列车动力学性能的影响,基于高速列车线路运行的重复性以及周期性,采用变步长迭代寻优控制算法,建立高速列车抗蛇行减振器半主动变阻尼控制系统,以转向架横向加速度峰值为目标函数,不断迭代寻找最有利于列... 详细信息

为改善轨道非平稳随机不平顺对列车动力学性能的影响,基于高速列车线路运行的重复性以及周期性,采用变步长迭代寻优控制算法,建立高速列车抗蛇行减振器半主动变阻尼控制系统,以转向架横向加速度峰值为目标函数,不断迭代寻找最有利于列车动力学性能的减振器阻尼值,改善了传统列车定阻尼值的弊端。多体动力学软件和控制系统仿真软件相结合联合仿真,仿真分析表明,轨道非平稳随机不平顺会使得车体和构架横向加速度、轮对横向力以及轮轨磨耗以倍数增加,严重影响列车动力学性能;通过变阻尼控制之后,构架横向加速度、轮对横向力以及轮对磨耗明显减小,车体横向加速度也略有减小,能够改善列车动力学性能,提高列车运行安全性与平稳性。

关键词：高速列车轨道非平稳随机不平顺抗蛇行减振器变步长迭代寻优列车动力学性能

基于FeSiB/PZT-82/FeSiB磁电复合材料的分芯闭环电流传感器研究

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仪表技术与传感器 2023年第6期 8-12,25页

作者：辛明勇王景琦徐长宝王宇张紫嫣鲁彩江贵州电网有限责任公司电力科学研究院贵州贵阳550005 西南交通大学机械工程学院四川成都610031

文中提出了一种分芯闭环磁电电流传感器,其由高磁导率、低磁滞的FeSiB/PZT-82/FeSiB磁电复合材料、3块硅钢磁芯和一对永磁体组成。为了实现磁电电流传感器的开合式安装,文中采用了分芯磁芯结构;载流导线产生的环形磁场经3块硅钢磁芯汇聚... 详细信息

文中提出了一种分芯闭环磁电电流传感器,其由高磁导率、低磁滞的FeSiB/PZT-82/FeSiB磁电复合材料、3块硅钢磁芯和一对永磁体组成。为了实现磁电电流传感器的开合式安装,文中采用了分芯磁芯结构;载流导线产生的环形磁场经3块硅钢磁芯汇聚到FeSiB/PZT-82/FeSiB磁电复合材料,然后基于复合材料的磁-力-电多场耦合效应,实现载流导线电流传感。通过仿真和实验对比分析,分芯磁芯结构的磁场汇聚效应对FeSiB/PZT-82/FeSiB传感性能具有显著的提高。含有磁芯结构的分芯闭环磁电电流传感器在无源情况下,对工频(50 Hz)电流的测量灵敏度达到17.379 mV/A,约为无磁芯FeSiB/PZT-82/FeSiB磁电复合材料的35倍;在0~10 A测量范围内,具有良好的线性关系。结果表明:由于该传感器的优异性能和分芯闭环结构,其在工频小电流监测领域具有广阔的应用空间。

关键词：磁电复合材料电流传感器分芯闭环电流传感器交流电流检测