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Study on a segmented electro-pneumatic braking system for heavy-haul trains

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Transportation Safety and Environment 2020年第3期2卷 216-225页

作者： Wei Wei Yong Jiang Yuan Zhang xubao Zhao Jun Zhang Dalian Jiaotong University 794 Huanghe RoadShahekou DistrictDalianLiaoning116208China Meishan CRRC Brake Science&Technology 683rd RoadScience and Technology Industrial ParkMeishanSichuan620010China

The large longitudinal impact of heavy-haul trains is the main factor limiting their development,and the asynchronous nature of train-braking systems is the main cause of this longitudinal *** this paper,a segmented electro-pneumatic braking solution fully compatible with the existing freight-train braking system in China is proposed to improve the synchrony of train-braking systems.A simulation model for this braking system is developed based on air-flow theory,the 120 distribution valve and electronic control *** braking characteristics obtained from simulations are compared to those from the train-brake testing platform,and show high *** this basis,the effects of the new braking system on the braking capacity and longitudinal impact of a 20000 t heavy-haul train are analysed by further *** results show that during service brakes,the segmented electro-pneumatic braking system can increase the braking capacity by 4.2–24.7%and reduce the coupler force by 21.6–68.0%.Therefore,it can be seen that the segmented electro-pneumatic braking system is a new type of electro-pneumatic brake that meets the needs of the Chinese railway *** solves the problem of the longitudinal impact of heavy-haul trains satisfactorily,and its compatibility with the existing braking system(resulting in a reduced modification workload)makes it possible to maintain normal operations on heavy-haul lines while trains undergo modification.

关键词： pneumatic brake electro-pneumatic brake air-flow heavy-haul train braking characteristics longitudinal dynamics coupler force

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左旋精氨酸在急性胰腺炎治疗中的剂量效应

西南国防医药 1999年第5期9卷 257-260页

作者：李广阔张肇达刘续宝郭月瑜田伏洲成都军区总医院外二科成都610083 华西医科大学附一院普外科成都610041 华西医科大学附一院肾病科

目的:探讨左旋精氨酸(L-Arg)在急性胰腺炎治疗中的剂量效应。方法:观察不同剂量L-Arg治疗急性水肿性胰腺炎(AEP)大鼠后,血浆和胰组织一氧化氮(NO)浓度、血浆淀粉酶、平均动脉压(MAP)、胰组织病理等的变化。结果:(1)AEP大鼠血浆、胰组织N... 详细信息

目的:探讨左旋精氨酸(L-Arg)在急性胰腺炎治疗中的剂量效应。方法:观察不同剂量L-Arg治疗急性水肿性胰腺炎(AEP)大鼠后,血浆和胰组织一氧化氮(NO)浓度、血浆淀粉酶、平均动脉压(MAP)、胰组织病理等的变化。结果:(1)AEP大鼠血浆、胰组织NO浓度明显降低,小剂量L-Arg(50mg,100mg/kg)升高了血浆、胰组织NO浓度,改善了大鼠AEP;随着L—Arg剂量的增加,达800mg、1600mg/kg时,血浆、胰组织NO浓度过度升高,加重AEP成为急性出血坏死性胰腺炎(AHNP),且以80mg/kg组最明显;(2)实验所用的L—Arg对MAP的影响较小。结论:L—Arg的作用机理与NO的生物学行为有密切关系,临床应用L-Arg治疗急性胰腺炎应注意其类似NO的“双刃性”,尤其大剂量应用要慎重。

关键词：急性胰腺炎平均动脉压左旋精氨酸一氧化氮

Guidelines for the diagnosis and treatment of pancreatic cancer in China (2021)

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Journal of Pancreatology 2021年第2期4卷 49-66页

作者： Yinmo Yang Xueli Bai Dapeng Bian Shouwang Cai Rufu Chen Feng Cao Menghua Dai Chihua Fang Deliang Fu Chunlin Ge Xiaochao Guo Chunyi Hao Jihui Hao Heguang Huang Zhixiang Jian Gang Jin Fei Li Haimin Li Shengping Li Weiqin Li Yixiong Li Hongzhen Li Tingbo Liang xubao liu Wenhui Lou Yi Miao Yiping Mou Chenghong Peng Renyi Qin Chenghao Shao Bei Sun Guang Tan Xiaodong Tian Huaizhi Wang Lei Wang Wei Wang Weilin Wang Junmin Wei Heshui Wu Wenming Wu Zheng Wu Jingyong Xu Changqing Yan Xiaoyu Yin Xianjun Yu Chunhui Yuan Taiping Zhang Jixin Zhang Jun Zhou Yupei Zhao on behalf of the Chinese Pancreatic Surgery Association Department of General Surgery Peking University First HospitalBeijing Department of Hepatobiliary and Pancreatic Surgery the First Affiliated Hospital of Medical CollegeZhejiang UniversityHangzhouZhejiang Province Departments of Endoscopy Peking University First HospitalBeijing Institute of Hepatobiliary Surgery of PLA Chinese PLA General HospitalBeijing Department of Pancreatobiliary Surgery Sun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhouGuangdong Province Department of General Surgery Xuanwu HospitalCapital Medical UniversityBeijing Department of General Surgery Peking Union Medical College HospitalChinese Academy of Medical Science&Peking Union Medical CollegeBeijing Department of Hepatobiliary Surgery Zhujiang HospitalSouthern Medical UniversityGuangzhouGuangdong Province Department of Pancreatic Surgery Huashan Hospital Fudan UniversityShanghai Department of General Surgery The First Affiliated Hospital of China Medical UniversityShenyangLiaoning Province Department of Imaging Peking University First HospitalBeijing Department of Hepato-Pancreato-Biliary Surgery Peking University Cancer Hospital&InstituteBeijing Department of Pancreatic Cancer Tianjin Medical University Cancer Institute and HospitalTianjin Department of General Surgery Fujian Medical University Union HospitalFuzhouFujian Province Department of General Surgery Guangdong Provincial People’s HospitalGuangzhouGuangdong Province Department of Hepatobiliary Pancreatic Surgery Changhai Hospital Affiliated to Navy Medical UniversityShanghai Department of Hepatobiliary Surgery Xijing HospitalFourth Military Medical UniversityXi’anShaanxi Province Department of Pancreatobiliary Surgery Sun Yat-sen University Cancer CenterGuangzhouGuangdong Province Department of General Surgery Jinling HospitalMedical School of Nanjing UniversityNanjingJiangsu Province Department of General Surgery Xiangya HospitalCentral South UniversityChangshaHunan Province Department of Radiation Oncology Peking University First H

The incidence of pancreatic cancer has been rising worldwide,and its clinical diagnosis and treatment remain a great *** present the update and improvements in the clinical diagnosis and treatment of pancreatic cancer in recent years,Chinese Pancreatic Association,the Chinese Society of Surgery,Chinese Medical Association revised the Guidelines for the Diagnosis and Treatment of Pancreatic Cancer in China(2014)after reviewing evidence-based and problem-oriented literature published during 2015-2021,mainly focusing on highlight issues regarding diagnosis and surgical treatment of pancreatic cancer,conversion strategies for locally advanced pancreatic cancer,treatment of pancreatic cancer with oligo metastasis,adjuvant and neoadjuvant therapy,standardized processing of surgical specimens and evaluation of surgical margin status,systemic treatment for unresectable pancreatic cancer,genetic testing,as well as postoperative follow up of patients with pancreatic *** recommendation items were finally proposed based on the above issues,and the quality of evidence and strength of recommendations were graded using the Grades of Recommendation,Assessment,Development,and Evaluation *** guideline aims to standardize the clinical diagnosis and therapy,especially surgical treatment of pancreatic cancer in China,and further improve the prognosis of patients with pancreatic cancer.

关键词： Diagnosis Guideline Multidisciplinary team Pancreatic cancer Treatment

Beam quality measurement and consistent safety standard for high power laser products

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Frontiers of Optoelectronics 2011年第4期4卷 393-397页

作者： Hong CHEN Zhibin YIN xubao WANG Tiechuan ZUO Institute of Laser Engineering Beijing University of Technology

With the development of laser technology,laser application technology increasingly plays a leading role in the field of industry. High power laser products and their safety requirements are attracting more attention. In laser industrial applications, laser beam quality and the system of laser beam propagation and focusing are greatly ignored. Furthermore, the basic safety standards for laser products have been neither widely publicized nor strictly enforced because of rapid development. This paper examines the underlying relationship between laser beam quality and laser manufacturing, and makes a comparison among different laser systems. It is also shown how the laser safety standards could be better understood and laser beam quality standard is advocated that directly relates to a mission requirement.

关键词： beam quality safety standards laser products

Sequence Analysis of mtDNA CO/Gene and Molecular Phylogeny of Different Geographical Populations of Bemisia tabaci (Gennadius)

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Agricultural Sciences in China 2005年第7期4卷 533-541页

作者： CHUDong ZHANGYou-jun CONGBin xubao-yun WUQing-jun ZHUGuo-ren InstituteofVegetablesandFlowers ChineseAcademyofAgriculturalSciencesBeijing100081P.R.China InstituteofVegetablesandFlowers ChineseAcademyofAgriculturalSciencesBeijing100081P.R.China／／CollegeofPlantProtectionShenyangAgriculturalUniversityShenyang110161P.R.China CollegeofPlantProtection ShenyangAgriculturalUniversityShenyang110161P.R.China

Bemisia tabaci(Gennadius) is a serious pest in many cropping systems worldwide and occurs in different biotypes. ThemtDNA COI gene of the 12 Bemisia tabaci (Gennadius) populations from different regions and countries were *** on mtDNA COI sequences, their biotypes were characterized and phylogenetic relationships among thesepopulations were established with the method of UPGMA. The results indicated the genetic similarity between thosepopulations from Beijing, Zhengzhou, Zaozhuang, Nanjing, Shanghai, Haikou, and the B-biotype populations fromCalifornia, Texas, Arizona reached 99.8-100%, which meant the nation-wide infested populations of *** in China inrecent years were B-biotypes. Another population collected from Kunming of Yunnan Province showed very high similaritywith Q-biotype *** from Spain and Morocco, which meant the Kunming population was Q-biotype. This is the firstreport on the invasion of Q-biotype into China.

关键词： Bemisia tabaci (Gennadius) mtDNA COI Biotype Phylogenetic tree

基于改进PSO算法的弹性胶泥缓冲器动力学建模研究

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振动与冲击 2020年第24期39卷 107-112,155页

作者：赵旭宝魏伟刘爽张渊大连交通大学软件学院辽宁大连116028 大连交通大学机车车辆工程学院辽宁大连116028 大连交通大学土木工程学院辽宁大连116028

针对弹性胶泥缓冲器动力学建模复杂以及模型仿真数据与测量数据吻合度低的问题,将缓冲器的结构原理与缓冲器加载、卸载工作过程结合起来,利用胶泥对速度的依赖特性,构建一种基于速度型的弹性胶泥缓冲器动力学模型。构造了动态调整惯性... 详细信息

针对弹性胶泥缓冲器动力学建模复杂以及模型仿真数据与测量数据吻合度低的问题,将缓冲器的结构原理与缓冲器加载、卸载工作过程结合起来,利用胶泥对速度的依赖特性,构建一种基于速度型的弹性胶泥缓冲器动力学模型。构造了动态调整惯性权值的改进微粒子群算法,并以落锤试验数据为基础,利用改进的算法对缓冲器动力学模型各参数进行优化求解。仿真结果表明:不同高度落锤仿真试验中,仿真数据和落锤试验数据总体吻合较好,具有较好的一致性,二者之间的最大车钩力和最大位移误差均小于5%。表明了该缓冲器动力学模型具备较高的准确度,该模型将为快捷货车纵向动力学性能的分析和弹性胶泥缓冲器性能优化提供有效的研究手段。

关键词：弹性胶泥缓冲器快捷货车微粒子群(PSO)算法动力学建模

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激光制造的短流程优势

中国激光 2008年第11期35卷 1660-1663页

作者：左铁钏王旭葆北京工业大学激光工程研究院国家产学研激光技术中心北京100124

通过对激光切割取代冲孔和修边模具,车身总装过程中激光焊接取代电阻点焊,以及车身不同部位不同厚度覆盖件的激光焊接的研究,展示了激光制造技术在汽车制造领域中的优势。介绍了激光宽带熔覆技术,与传统粉末冶金烧结工艺相对比,该激光... 详细信息

通过对激光切割取代冲孔和修边模具,车身总装过程中激光焊接取代电阻点焊,以及车身不同部位不同厚度覆盖件的激光焊接的研究,展示了激光制造技术在汽车制造领域中的优势。介绍了激光宽带熔覆技术,与传统粉末冶金烧结工艺相对比,该激光制造短流程工艺不仅能够提高生产率、缩短制造工艺流程,而且能够降低成本、节约能源。

关键词：激光技术短流程激光拼焊激光熔覆

152 W high-power blue diode laser operated at 447 nm

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Journal of Semiconductors 2017年第7期38卷 71-73页

作者： Peng Wu Ling Zhang Haijuan Yu Xiandan Yuan Zhiyan Zhang Pengfei Zhao Shuzhen Zou Chaojian He Yaoyao Qi Yingying Yang Gang Li xubao Wang Xuechun Lin Institute of Laser Engineering Beijing University of Technology Laboratory of All-Solid-State Light Sources Institute of Semiconductors Chinese Academy of Sciences

We demonstrate a high-power blue diode laser operated at 447 nm combining laser diodes using an optical fiber bundle. As many as 127 diode lasers at 447 nm were coupled into 400 μm/0.22 NA fibers using an aspherical lens group with different focus lengths. The bare fibers were mechanically bundled through high temperature ultraviolet adhesive after the coatings of the 127 fibers were stripped. The diameter of the fiber bundle was 6 mm. The total output power of such a bundle was 152 W with electro-optical conversion efficiency of 27.56%and the RMS power instability was less than ±1% within 3 h.

关键词： high power blue diode laser fiber bundle optical power combining

Web-Based Information Systems and Applications: A Survey

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Wuhan University Journal of Natural Sciences 2004年第5期9卷 537-541页

作者： xubao-wen XULei MENGXiao-feng YUGe LUZheng-ding HEYan-xiang SHENJun-yi DepartmentofComputerScienceandEngineering.SouthcastUniversity Nanjing210096Jiangsu.China SchoolofInformation.RcnminUniversityofChina.Beijing100872.China DepartmentofCoral.raterScience NorflieasternUniversityShenyang110001.LiaoningChina CollegeofComputerScienceandTechnology HuazhongUniversityofScienceandTechnology.Wuhan130074Hubei.China SchoolofComputer WuhanUniversityWuhan.130072HubeiChina SchoolofElectronicsandInformationEngineering Xi＇anJiaotongUniversityXi＇an710049Shaanxi.China

Biography: XU Bao-wen(1961-), male, Ph.D. Professor, research direction: programming language, software engineering, Web-based technology, etc.

关键词： Web WWW 信息系统因特网数据管理