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有两种故障状态的两部件串联系统的预防维修策略

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运筹与管理 2021年第3期30卷 117-122,136页

作者：高俏俏山西大学经济与管理学院山西太原030006

本文研究的是由两个部件串联组成且有两种故障状态的系统的预防维修策略,当系统的工作时间达到T时进行预防维修,预防维修使部件恢复到上一次故障维修后的状态。每个部件发生故障都有两种状态,可维修和不可维修。当部件的故障为可维修故... 详细信息

本文研究的是由两个部件串联组成且有两种故障状态的系统的预防维修策略,当系统的工作时间达到T时进行预防维修,预防维修使部件恢复到上一次故障维修后的状态。每个部件发生故障都有两种状态,可维修和不可维修。当部件的故障为可维修故障时,修理工对其进行故障维修,且每次故障维修后的工作时间形成随机递减的几何过程,每次故障后的维修时间形成随机递增的几何过程。当部件发生N次可维修故障或一次不可维修故障时进行更换。以部件进行预防维修的间隔和更换前的可维修故障次数N组成的二维策略(T,N)为策略,利用更新过程和几何过程理论求出了系统经长期运行单位时间内期望费用的表达式,并给出了具体例子和数值分析。

关键词：更新过程几何过程故障维修预防维修期望费用

The Sharpa People in Drenthang

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China's Tibet 2009年第1期20卷 24-33页

作者： Wang Jiexue Ba qiao

In the pristine forest between the north flank of the Himalayas and the east flank of Qomolangma,it is Drenthang-a town in Shigatse Prefecture where only a river separates it from Nepal but there is no road *** area has yet to undergo full democratic reform including the establishment of the people’s ***,however,is where the special ethnic group named the Sharpa people is *** an elevation of 2,040 meters,the local climate tends to be tropical and *** town has six administrative villages with 390 households(about 1,963 people).Per capital income is less than a thousand *** isolation and a lack of transportation mean that all substances in and out of Drenthang must be carried by pack animals,without any modern means of transportation.

关键词：中国西藏喜马拉雅山种群

Effects of SiC_(p) on microstructures of semi-solid extruded AZ91D magnesium alloys in recrystallization process

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China Foundry 2021年第6期18卷 565-573页

作者： Ao-xue Jiang Zhi-yong You Zhuang-zheng Duan Gang-ping qiao Jin-shan Zhang Ling-bing Guo College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China Shanxi Huaxiang Group Co. Ltd.Linfen 041000ShanxiChina

AZ91 D and 8.5 vol.%SiC_(p)/AZ91 D magnesium matrix composites were fabricated by a semi-solid extruded processing method,and treated with solution and aging heat *** effects of SiC_(p)on the microstructures of the semi-solid extruded AZ91 D magnesium alloy during recrystallization were studied by observing and analyzing the microstructure evolution during extrusions and heat *** results show that the addition of SiC_(p)inhibits the dynamic recrystallization of AZ91 D during the semi-solid extrusion with only 26% of the volume fraction of ***,the addition of SiC_(p)refines the sizes of grains and second phases,and upgrades the volume fraction of second *** solution and aging treatment,the recrystallization continues,and the addition of SiC_(p)promotes the recrystallization and the recrystallized microstructure is much more ***,the sizes of grains and second phases continue to be refined,and the volume fraction of second phases continues to increase.

关键词： SiC_(p)/AZ91D composites semi-solid extrusion recrystallization microstructure

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基于伪逆算法的冷镦坯模具的优化(英文)

中国有色金属学会会刊：英文版 2012年第S2期22卷 207-213页

作者： Ali HALOUANI Yu-ming LI ABBES Boussad Ying-qiao GUO GRESPI/MPSE Université de Reims Champagne-Ardenne Moulin de la Housse

基于对最终产品形状的认识,提出一种新的快速的针对多工步轴对称冷锻建模方法—"伪逆法(PIA)"。为了考虑变形路径,引入了一些中间构型并且采用自由表面对这些中间构形进行修正而不采用接触算法。利用等效应力的概念和拉伸曲线,提出了一... 详细信息

基于对最终产品形状的认识,提出一种新的快速的针对多工步轴对称冷锻建模方法—"伪逆法(PIA)"。为了考虑变形路径,引入了一些中间构型并且采用自由表面对这些中间构形进行修正而不采用接触算法。利用等效应力的概念和拉伸曲线,提出了一种新的快速而健壮的塑性积分直接算法。数值试验表明:与增量法相比,伪逆法速度非常快。PIA被用于多工步冷锻工艺预制体模具优化设计过程中,该优化过程以最大限度减少在锻造过程中产生的等效塑性应变和需要的冲压力为目标,预制体模具的形状采用B样条曲线描述,以B样条曲线控制点的纵坐标为设计变量。目标函数的演变表明了模具形状优化对锻造件的质量和节能的重要性。通过与传统增量法的结果相比较,体现出了PIA的高效性和准确性。

关键词：冷锻伪逆算法预制坯设计 B样条形状优化 Pareto前沿

Thoughts of geographical indication in Shanxi province based on comparison with six provinces of Central China

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Journal of Modern Accounting and Auditing 2008年第10期4卷 23-25,58页

作者： SHI Xue-qiao College of Economics and Management North University of China Shanxi 030051 China

Geographical indication is indication not only of origin but also of quality, and what＇s more, it is a kind of intellectual property rights. The paper analyzes the problems of geographical indication in Shanxi province by comparison with six provinces of Central China, suggesting that in order to actively expand protective space of geographical indication, two key things should be done： Firstly, the transition from resource advantages to brand advantages should be actively promoted; secondly, the governments and industry associations should play their effective roles.

关键词： six provinces of central China Shanxi province geographical indication

CK5/6-positive,P63-positive lymphoepithelioma-like hepatocellular carcinoma:A case report and literature review

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World Journal of Clinical Cases 2023年第19期11卷 4640-4647页

作者： Hong-Tao Tang Wei Lin Wei-qiao Zhang Jun-Lin Qian Kai Li Kun He Graduate School of Guangdong Medical University Zhanjiang 524002Guangdong ProvinceChina Department of Hepatobiliary Surgery Zhongshan People’s HospitalZhongshan 528400Guangdong ProvinceChina

BACKGROUND Lymphoepithelioma-like carcinoma(LELC),a rare and unique variant of liver cancer,can be divided into lymphoepithelioma-like hepatocellular carcinoma and lymphoepithelioma-like intrahepatic *** lymphocytic infiltration is its characteristic pathological *** recent years,the number of reported cases of this type has increased each *** have shown that lymphoepithelioma-like cholangiocarcinoma occurs more frequently in Asian women;LELC is associated with Epstein–Barr virus infection of liver cells of epithelial *** research shows that the prognosis of this tumour is *** SUMMARY A 38-year-old female patient was hospitalized after 3 mo of abdominal pain and *** had been infected with hepatitis B virus more than 10 years *** patient was hospitalized on January 21,*** resonance imaging showed a 36 mm×28 mm mass under the envelope of the left inner lobe of the *** metastasis of lymph nodes or other organs was *** left hemihepatectomy,biopsy and immunohistochemistry yielded a final diagnosis of lymphoepithelial hepatocellular *** 12 mo of outpatient follow-up and chemotherapy,no tumour metastases were found on the latest computed tomography *** Herein,the patient was treated surgically and then followed up as an outpatient for 12 *** case will further expand our overall knowledge of the diagnosis and treatment of this rare tumor.

关键词： Liver cancer Lymphoepithelioma-like carcinoma Hepatocellular carcinoma Epstein–Barr virus Literature review Case report

The first photometric investigation of the contact binary OQ Cam

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Research in Astronomy and Astrophysics 2020年第11期20卷 252-258页

作者： Ya-Ni Guo Kai Li Qi-Qi Xia Xing Gao Lin-qiao Jiang Yuan Liu Shandong Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment School of Space Science and PhysicsInstitute of Space SciencesShandong UniversityWeihai 264209China Xinjiang Astronomical Observatory Urumqi 830011China Artificial Intelligence Key Laboratory of Sichuan Province Sichuan University of Science&EngineeringZigong 643000China Qilu Institute of Technology Jinan 250200China

The first charge-coupled device photometric light curves in B,V,Rc,and Ic bands of the short-period contact binary star OQ Cam are *** analyzing the light curves with the WilsonDevinney code,it is found that OQ Cam is a W-type shallow contact binary star with a contact degree of f=20.2%.Based on the O-C analyzing,the orbit period displays a long term increasing with a rate of d P/dt=4.40×10^-7 d *** increasing in orbit period can be interpreted by mass transfer from the less massive component to the more massive *** the orbit period increases,OQ Cam would evolve from the present shallow contact configuration to a non-contact *** it may be a potential candidate to confirm the thermal relaxation oscillation theory.

关键词： stars binaries close stars binaries eclipsing stars evolution stars individual(OQ Cam)

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转动课堂模式在大学教学中的设计与实施

渤海大学学报（自然科学版） 2016年第2期37卷 145-149页

作者：丛俏周颖渤海大学化学化工学院辽宁锦州121013 渤海大学教务处辽宁锦州121013

为全面提高人才培养质量,为教与学的进一步发展提供新的思路,本文详细介绍了转动课堂的含义、转动课堂的操作路径及优势,阐述了转动课堂模式下的课程教学,系统分析了转动课堂的特色与创新,为相关研究和工作提供参考.

关键词：转动课堂操作路径课程教学特色

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Information Soliton

Journal of Modern Physics 2013年第7期4卷 923-929页

作者： qiao Bi Kongzhi Song Department of Physical Science and Technology Science School Wuhan University of Technology Wuhan China

In this work, for understanding bio-information transmission through long distance a type of nonlinear master equation is studied. We found that the nonlinear power term can introduce a novel solution of the equation, in which a possible invariant structure as an information soliton can exist when time elapses long enough. This provides a sort of constructive channel for bio-information transmission for long distance.

关键词： Quantum Information Coherent State Nonlinear Kinetic Equation