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不确定性条件下的设备替换优化的随机动态规划方法

1982年

作者： (英)梅森

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交通运输系统工程与信息 2014年第3期14卷 76-84页

作者： FAN (David)Wei MACHEMEHL Randy GEMAR mason BROWN Leonard 北卡罗来纳大学夏洛特分校土木与环境工程系德克萨斯大学奥斯汀分校交通研究中心德克萨斯大学泰勒分校计算机学院

本文提出了一种解决设备更新换代优化(ERO)问题的随机动态规划(sDP)模型,用以明确地解释在车辆利用中的不确定性,并采用Bellman算法解决ERO sDP问题.针对sDP状态空间的增长,提出了特殊简化算法,以解决动态规划方法中固有的'维数灾'问题... 详细信息

本文提出了一种解决设备更新换代优化(ERO)问题的随机动态规划(sDP)模型,用以明确地解释在车辆利用中的不确定性,并采用Bellman算法解决ERO sDP问题.针对sDP状态空间的增长,提出了特殊简化算法,以解决动态规划方法中固有的'维数灾'问题,确保所需的内存和计算时间不会随着时间范围的增加而成倍增长.并对sDP软件的实现技术、功能和图形用户界面(GUI)进行了讨论,开发了基于sDP的ERO软件,并使用美国得克萨斯交通局(TxDOT)现有车辆数据进行验证.对统计结果、软件计算时间和求解效果进行综合分析,结果显示,使用该ERO软件,估计大量成本可以节省.

关键词：系统工程动态规划设备更换交通运输

利用质疑改进教育信息技术标准化活动：更多关注其范围和原理(英文)

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华东师范大学学报（自然科学版） 2012年第2期 25-34,41页

作者： T.HOEL J.mason 奥斯陆和阿克什胡斯应用技术学院教育研发中心奥斯陆0130挪威昆士兰科技大学教育学院昆士兰4001澳大利亚

标准化对于开发"学习、教育和培训"(LET)中使用的"信息通信技术"(ICT)有重要意义,但ICT的利益相关者(stakeholders)却往往质疑标准化活动.本文提出,利用这种质疑形式来分析和改进当前的ICT标准化活动.讨论了由各方参与产生ICT标准过程... 详细信息

标准化对于开发"学习、教育和培训"(LET)中使用的"信息通信技术"(ICT)有重要意义,但ICT的利益相关者(stakeholders)却往往质疑标准化活动.本文提出,利用这种质疑形式来分析和改进当前的ICT标准化活动.讨论了由各方参与产生ICT标准过程的模型框架,其中一系列"为什么"的问题(Why questions)起着重要作用.讨论主要围绕两个方面:一是标准及相关事物在发展过程中的管理与核准;二是如何识别LET中的相关问题与可用来解决这些问题的创新技术.给出了两个事例:一个是对"内容共享对象参考模型"(sharable Content Object Refer-ence Model,sCORM)的质疑,这能帮助理解该模型;特别是对其适用范围(scope)的质疑而使该模型更完善.另一个是对制定"新工作条款"(New Work Items)必要性的质疑,使人们认识到澄清标准中有关技术原理(rationale)的重要性.

关键词：标准管理 ICT标准数字化学习信息系统架构企业框架 ITLET(学习、教育和培训中的信息技术)

seasonal and geographical variation in diapause and cold hardiness of the Asian corn borer, Ostrinia furnacalis

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Insect science 2015年第4期22卷 578-586页

作者： Hai-Cui Xie Dun-song Li Hong-Gang Zhang Charles E. mason Zhen-Ying Wang Xin Lu Wan-Zhi Cai Kang-Lai He The state Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences Beijing 100193 Department of Entomology China Agriculture University Beijing 100193 The Plant Protection Research Institute Guangdong Academy of Agricultural Sciences Guangzhou 510640 China Department of Entomology and Wildlife Ecology University of Delaware 531 S College Ave Rm 250 Newark DE 19716-2160 USA Institute of Plant Protection Jilin Academy of Agricultural Sciences Gongzhuling 136100 Jilin China

Asian corn borer, Ostrinia furnacalis （Guenee）, is a key corn pest in the Asian-Western Pacific countries. It overwinters as flail-grown larvae in plant stalks or in a spun-silk covering located in the plant debris in the temperate regions of China. supercooling point （sCP） and survival rate after low sub-zero temperature treatment were assessed for field-collected populations in the laboratory using a cool bath with a 1 ℃/min cooling rate until -40℃. Mean sCPs were varied among geographical populations, with a significant decline from -22.7℃ of Haikou, the multivoltine tropical population in the south, to -28.5℃ of Gongzhuling, the univoltine temperate population in the northeast of China. In addition, there was more than 1℃ difference in sCP between Gongzhuling univoltine and bivoltine populations that were from the same geographic origin. Mean sCPs of the Guangzhou population fluctuated over the year, with significantly lower sCPs in winter than in other seasons, which correlated with a significantly higher proportion of diapausing larvae in winter than in other seasons. Over 41% of overwintering larvae from the northeast population could withstand to be supercooled for a few minutes to the low sub-zero temperature of-40℃, but only 6.7% of their southern counterparts did so. The findings from this study suggest that O. furnacalis mostly takes advantage of freeze avoidance as diapausing larvae for overwintering in the southern region, whereas it exhibits freeze tolerance in diapause in the northeastern region.

关键词： cold hardiness diapause geographical population Ostriniafurnacalis overwintering seasonality

Development of Competitive Advantage in Apparel Industry in Kenya

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sociology study 2012年第5期2卷 337-350页

作者： Anne Mastamet-mason Michael Ogembo-Kachienga Kenya Polytechnic University College Kenya Tshwane University of Technology South Africa University of Pretoria South Africa Kenya Polytechnic University College Kenya

The Kenyan apparel industry has played a major role in the country＇s economic development; however the sector＇s competitiveness has decreased due to inadequate industrial strategy and loss of global markets resulting from elimination of quotas in 2005. China and other Asian countries＇ ability to produce quality products efficiently at lower comparative costs has been threatening apparel manufacturers in most developing countries in Africa. The purpose of this study is to analyse Kenya＇s apparel industry＇s current situation and to recommend some strategies for regaining business competitiveness in the apparel sector. This paper examines how apparel firms could develop competitive advantages in both local and global markets. It uses Porter＇s diamond and business value chain models as a basis of analysis for interpreting competitive factors within Kenya＇s apparel industry. In addition to extensive literature reviews, the paper provides in-depth overview of Kenya＇s apparel sector business dynamics and its relationships with local and global markets. Conclusions are drawn based on the analyses of Porter＇s theoretical models in relationship to Kenya＇s apparel industry business dynamics. Taking into account the global apparel business factors, recommendations are made on how the Kenya＇s apparel industry can regain business competitiveness.

关键词： Competitive advantage apparel industry Kenya

Electrical and band-gap properties of amorphous zinc-indium-tin oxide thin films

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Progress in Natural science:Materials International 2012年第1期22卷 1-6页

作者： D.B. Buchholz D.E. Proffit M.D. Wisser T.O. mason R.P.H. Chang Department of Materials science and Engineering Northwestern University 2220 Campus Drive Cook Hall Room 2013 Evanston IL 60208 USA

Zinc-indium-tin oxide (ZITO) films were grown by pulsed-laser deposition. Three different material compositions were investigated: ZITO-30, ZITO-50 and ZITO-70 in which 30%, 50% and 70%, respectively, of the indium in the In 2 O 3 structure was replaced by substitution with zinc and tin in equal molar proportions (co-substitution): In 2 2x Zn x sn x O 3 , where x 0.3, 0.5, 0.7. All ZITO films grown at room temperature were amorphous. The first evidence of crystallinity was observed at higher deposition-temperature as the degree of co-substitution was increased. A decrease in mobility and conductivity was also observed as the degree of co-substitution was increased. The highest mobility for ZITO-30 and ZITO-50 was observed at deposition temperatures just prior to crystallization. The effect of deposition temperature on carrier concentration was minor compared to the effect of oxygen partial pressure during deposition.

关键词： Transparent conducting oxide semiconductor Oxide Amorphous Deposition temperature

嗜肝DNA病毒感染的抗病毒治疗:难点与现状

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国外医学(微生物学分册) 1990年第5期13卷 209-209页

作者： mason Ws 阎辉

对嗜肝DNA病毒慢性感染的治疗目前仍是个特别困难的问题。本文从该类病毒复制的特点及疗效评价等方面作了分析,并对近年应用的几种抗病毒化疗剂应用情况作了述评,特别提到了一种可能很有希望的中草药在这方面的应用。

关键词： DNA 抑制剂慢性感染浮选药剂病毒复制病毒感染

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第一届世界口腔内科学专题讨论会

国外医学（口腔医学分册） 1989年第6期16卷 352-353,331页

作者： mason D 萧燕

第一届世界口腔内科学专题讨论会1988年6月在美国举行。本文对会议议题作了全面的总结介绍。明确了口腔内科学的定义、范围。回顾了近年来口腔内科领域的研究成果,提出了今后研究和教育的方向及目标,并对口腔内科学如何发展提出了一系... 详细信息

第一届世界口腔内科学专题讨论会1988年6月在美国举行。本文对会议议题作了全面的总结介绍。明确了口腔内科学的定义、范围。回顾了近年来口腔内科领域的研究成果,提出了今后研究和教育的方向及目标,并对口腔内科学如何发展提出了一系列设想。

关键词：口腔内科学学术会议

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灰熔聚体形成和生长的实验及理论研究

煤炭综合利用译丛 1989年第3期12卷 104-110页

作者： R.H.Carty D.M.mason s.Kline s.P.Babu 王永刚美国煤气工艺研究院太原工业大学

0 前言最近对流化床灰熔聚气化的改进是增加了复式脱硫系统。在这一工艺配置中,煤中的大部分硫由内部床的添加剂(即石灰石或白云石)除去。剩余的硫气体由铁酸锌外部床的吸附剂从热的产物气体中除去。最后的结果是热的产物气体含有大约5 ... 详细信息

0 前言最近对流化床灰熔聚气化的改进是增加了复式脱硫系统。在这一工艺配置中,煤中的大部分硫由内部床的添加剂(即石灰石或白云石)除去。剩余的硫气体由铁酸锌外部床的吸附剂从热的产物气体中除去。最后的结果是热的产物气体含有大约5 ppm的硫量。在外部吸收床再生时,含有sO_2的再生逸出气循环到气化炉内,被还原气将还原成H_2s,H_2s再同脱硫添加剂CaO反应。在流化床气化炉中使用白云石(CaCO_3·MgCO_3)或石灰石(CaCO_3)

关键词：灰熔聚体煤气化流化床硫

Clinical classification of symptomatic heterotopic pancreas of the stomach and duodenum:A case series and systematic literature review

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World Journal of Gastroenterology 2022年第14期28卷 1455-1478页

作者： Michael T Le Compte Brandon mason Keenan J Robbins Motoyo Yano Deyali Chatterjee Ryan C Fields steven M strasberg William G Hawkins Department of surgical Oncology University of North CarolinaRaleighNC 27608United States Department of Radiology Stillwater Medical CenterStillwaterOK 74074United States Department of General surgery Washington University St.LouisSt.LouisMO 63110-8109United States Department of Radiology Mayo ClinicPhoenixAZ 8505United States Department of Pathology and Immunology MD Anderson Cancer CenterHoustonTX 77030United States Department of surgical Oncology Washington University School of MedicineSt.LouisMO 63110-8109United States section of Hepatobiliary-Pancreatic and GI surgery Washington University St.LouisSt.LouisMO 63110United States

BACKGROUND Heterotopic pancreas(HP)is an aberrant anatomic malformation that occurs most commonly in the upper gastrointestinal *** the majority of heterotopic pancreatic lesions are asymptomatic,many manifest severe clinical symptoms which require surgical or endoscopic *** of the clinical manifestations and symptoms of HP is limited due to the lack of large volume studies in the *** purpose of this study is to review symptomatic cases at a single center and compare these to a systematic review of the literature in order to characterize common clinical manifestations and treatment of this *** To classify the common clinical manifestations of heterotopic *** A retrospective review was conducted of pathologic samples containing heterotopic pancreas from *** was limited to HP of the upper gastrointestinal tract due to the frequency of presentation in this *** patients were identified from review of the medical records and clinical symptoms were *** were compared to a systematic review of the literature utilizing Pub Med and Embase searches for papers pertaining to heterotopic *** describing symptomatic presentation of HP were selected for *** including demographics,symptoms,presentation and treatment were compiled and *** Twenty-nine patient were identified with HP at a single center,with six of these identified has having clinical *** manifestations included,gastrointestinal bleeding,gastric ulceration with/without perforation,pancreatitis,and gastric outlet *** review of the literature yielded 232 publications detailing symptomatic cases with only 20 studies describing ten or more *** and multi-patient studies were combined to form a cohort of 934 symptomatic *** majority of patients presented with abdominal pain(67%)combined with one of the following clinical catego

关键词： Heterotopic pancreas Ectopic pancreas Aberrant pancreas Pancreatic rest Groove pancreatitis