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A Distributionally Robust Optimization Method for Passenger Flow Control Strategy and Train Scheduling on an Urban Rail Transit Line

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Engineering 2022年第5期8卷 202-220页

作者： Yahan Lu Lixing Yang Kai Yang Ziyou Gao Housheng Zhou Fanting Meng jianguo qi State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong UniversityBeijing 100044China

Regular coronavirus disease 2019(COVID-19)epidemic prevention and control have raised new require-ments that necessitate operation-strategy innovation in urban rail *** alleviate increasingly seri-ous congestion and further reduce the risk of cross-infection,a novel two-stage distributionally robust optimization(DRO)model is explicitly constructed,in which the probability distribution of stochastic scenarios is only partially known in *** the proposed model,the mean-conditional value-at-risk(CVaR)criterion is employed to obtain a tradeoff between the expected number of waiting passen-gers and the risk of congestion on an urban rail transit *** relationship between the proposed DRO model and the traditional two-stage stochastic programming(SP)model is also ***,to overcome the obstacle of model solvability resulting from imprecise probability distributions,a discrepancy-based ambiguity set is used to transform the robust counterpart into its computationally tractable form.A hybrid algorithm that combines a local search algorithm with a mixed-integer linear programming(MILP)solver is developed to improve the computational efficiency of large-scale ***,a series of numerical examples with real-world operation data are executed to validate the pro-posed approaches.

关键词： Passenger flow control Train scheduling Distributionally robust optimization Stochastic and dynamic passenger demand Ambiguity set

Potassium Uptake and Transport in Apple Roots Under Drought Stress

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Horticultural Plant Journal 2019年第1期5卷 10-16页

作者： jianguo qi Simin Sun Lin Yang Mingjun Li Fengwang Ma Yangjun Zou State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple College of Horticulture Northwest A & F University

As one of the most important mineral nutrient elements, potassium(K^+) plays an important role in many plant physiological processes and determines both the yield and quality of crops. There are two typical gene families that regulate K^+transport in higher plants, including K^+channels and K^+transporters. However, little is known about how these channels and transporters divide their work in response to drought stress. In this study, the hydroponic experiment was conducted on Malus hupehensis. The K^+content was found to decrease in response to drought stress in M. hupehensis, the aboveground decreased by 34.15% and the underground decreased by 3.97%. Meanwhile, the root morphology change was detected by scanning the root system. Under conditions of drought, the genes encoding K^+transporters were upregulated including MdCHX1.3, MdCHX4.11, MdCHX4.8, MdCHX4.9, Md HKT1, and MdHAK3.2. The net influx of K^+was inhibited by 19.47% with the action of K^+channel inhibitors(CsCl), however a significant decrease(80.99%; P < 0.05) was found in roots exposed to a PM H+-ATPase(orthovanadate) inhibitor by utilizing a non-invasive micro-test technique. The trend of H+efflux was similar to that of K^+. The data suggested that the positive influx of K^+through the transporter accounted for the main K^+uptake under drought stress. These results suggest that we can improve the uptake of K^+by purposely up-regulating specific K^+transporters under drought stress. This process may improve growth, yield, quality, and stress tolerance in apple trees.

关键词： apple potassium drought stress transporter root morphology uptake

Present situation and future of welding machinery industry　

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China Welding 1994年第2期3卷 142-145页

作者： LI jianguo and ZHU qi (Chengdu Electric Welding Machine Research Institute (610051 ))

The present situation of welding machinery industry in China is presented in *** the basis of the analysis, the future development and practicable way are proposed.

关键词： Present situation and future of welding machinery industry

Relationship between subtypes of MRI-confirmed acute ischemic stroke based on OCSP and TOAST classifications

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Neural Regeneration Research 2008年第7期3卷 798-801页

作者： Feng qiu Xiaokun qi jianguo Liu Wenluo Zhang qi Wang Department of Neurology Navy General Hospital of Chinese PLA Beijing 100037 China

BACKGROUND： Two classification systems exist for subtypes of acute cerebral infarction. One was developed for the Trial of Org 10172 in Acute Stroke Treatment （TOAST）, based primarily on etiology. The other is the Oxfordshire Community Stroke Project （OCSP）, based on clinical features. OBJECTIVE： To evaluate the relationship between OCSP and TOAST classifications in terms of stroke location and etiology in 126 patients with acute ischemic stroke confirmed by transcranial magnetic resonance imaging （MRI）. DESIGN, TIME AND SETTING： Retrospective case analysis. Transcranial MRI, diffusion weighted imaging, and magnetic resonance angiography were performed in 126 patients with acute stroke during the first 48 hours following admission to the Department of Neurology, Navy General Hospital of Chinese PLA. PARTICIPANTS： A total of 126 patients with acute stroke, comprised of 71 males and 55 females, admitted to the Navy General Hospital of Chinese PLA between December 2005 and April 2006 were included. METHODS： Of 126 patients with acute stroke, 13 exhibited total anterior circulation infarcts （TACI）, 51 had partial anterior circulation infarcts （PACI）, 28 suffered posterior circulation infarcts （POCI）, and 34 had lacunar infarcts （LACI） based on OCSP classification. However, according to TOAST classification, 19 cases were a result of large-artery atherosclerosis, 32 by cardioembolism, 36 by small-vessel occlusion, 1 by stroke of other determined etiology, and 38 by stroke of undetermined etiology. MAIN OUTCOME MEASURES： The corresponding relationship of the subtypes of acute stroke based on OCSP and TOAST. RESULTS： Of patients with TACI, 8 （61.5%） were caused by cardioembolism. Of patients with PACI, 16 （31.4%） were caused by large-artery atherosclerosis and 17 （33.3%） by cardioembolism. Of patients with POCI, 12 （42.8%） were a result of small-vessel occlusion. Of patients with LACI, 17 （50.0%） were caused by hypertension and arteriolar sclerosis. CONCLUSIO

关键词： cerebral infarction classification diagnosis

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用科学发展观统领经济发展方式转变

财贸经济 2010年第4期31卷 5-12页

作者：齐建国中国社会科学院数量与技术经济研究所

本文对在科学发展观下转变经济发展方式的内涵进行了新的探索,认为其核心是处理好人与人之间的物质利益分配关系,处理好人与自然的关系,实现社会的物质利益关系和谐,实现人与自然的和谐。在未来一个时期,中国转变经济发展方式的核心是... 详细信息

本文对在科学发展观下转变经济发展方式的内涵进行了新的探索,认为其核心是处理好人与人之间的物质利益分配关系,处理好人与自然的关系,实现社会的物质利益关系和谐,实现人与自然的和谐。在未来一个时期,中国转变经济发展方式的核心是转变经济增长方式,实现可持续的经济增长。针对中国经济发展方式存在的八大问题,本文提出了加速转变经济发展方式的对策。

关键词：经济增长科学发展观转变经济发展方式

2008--2009：国际金融危机下的中国经济分析与预测

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财贸经济 2009年第1期30卷 5-11页

作者：齐建国中国社会科学院数量经济与技术经济研究所副所长、研究员 100732

本文分析了中国改革开放以来的四个经济增长周期,认为2008年在美国次贷危机引起的国际金融危机影响下,中国经济开始进入了第五个周期。文章较为全面地分析了2008年中国经济形势,并对2009年中国经济增长趋势进行了分析和预测。

关键词：经济周期经济危机经济形势金融危机经济增长

基于不确定客流的高速铁路列车停站方案优化方法

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铁道学报 2016年第7期38卷 1-7页

作者：牛丰戚建国秦进中南大学交通运输工程学院湖南长沙410075 中国铁路总公司北京100844 北京交通大学轨道交通控制与安全国家重点实验室北京100044

利用不确定变量刻画高铁车站客流需求不确定性的基础上,以最小化区段内开行列车的总停站次数为优化目标,以客流需求得到满足应达到的置信水平、列车的最大停站次数及车站所需最少停站列车数量等为约束条件,构建不确定客流条件下高速铁... 详细信息

利用不确定变量刻画高铁车站客流需求不确定性的基础上,以最小化区段内开行列车的总停站次数为优化目标,以客流需求得到满足应达到的置信水平、列车的最大停站次数及车站所需最少停站列车数量等为约束条件,构建不确定客流条件下高速铁路列车停站方案设计问题的机会约束规划模型,并利用不确定理论的相关知识将其转化为确定性的等价类模型,通过MATLAB平台调用GUROBI优化软件对模型进行求解和计算分析。最后,以武广段高速铁路作为实际背景,在假设列车开行对数和开行区间已知的前提下,通过上述方法求得最优列车停站方案。算例结果验证本文所提方法具有良好的优化质量和计算效率。

关键词：高速铁路停站方案不确定理论机会约束规划模型

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基于全程物流的铁路到达端营销策略探讨

铁道运输与经济 2021年第9期43卷 58-62页

作者：齐建国中国铁路兰州局集团有限公司货运部甘肃兰州730000

铁路到达端营销是相对既有发运端营销的新模式,是基于物流服务视角,利用跨局合作和铁路联动优势,以分工合作、优势互补的营销手段和最佳运输方式,辅以多种增值服务尝试开展的铁路全程物流服务。兰州局集团公司以到达宁夏地区疏港矿石为... 详细信息

铁路到达端营销是相对既有发运端营销的新模式,是基于物流服务视角,利用跨局合作和铁路联动优势,以分工合作、优势互补的营销手段和最佳运输方式,辅以多种增值服务尝试开展的铁路全程物流服务。兰州局集团公司以到达宁夏地区疏港矿石为突破口,通过组建合作联盟、建立跨局战略协同、采取灵活价格政策、完善补强设施设备、建立接取送达服务体系、推出定制化增值项目等措施,组织开展铁路全程物流服务,吸引企业选择铁路运输疏港矿石和发往港口地区的合金产品,取得较好效果。

关键词：铁路全程物流大宗货物到达端营销合作联盟

开放经济下环境污染的分解分析——基于1990～2003年间我国各省市的面板数据

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统计研究 2007年第1期24卷 47-53页

作者：于峰齐建国中国社会科学院研究生院数量经济与技术经济系中国社会科学院研究生院数量经济与技术经济研究所

本文试图揭示开放经济条件下我国主要经济要素与环境污染的关系。在Antweiler（2001）模型基础上，以SO2排放量表征环境污染水平，对1990-2003年间除西藏以外我国29个省及直辖市的面板数据进行回归分析，结果表明：经济规模的扩大恶化... 详细信息

本文试图揭示开放经济条件下我国主要经济要素与环境污染的关系。在Antweiler（2001）模型基础上，以SO2排放量表征环境污染水平，对1990-2003年间除西藏以外我国29个省及直辖市的面板数据进行回归分析，结果表明：经济规模的扩大恶化了我国环境；技术进步和经济结构升级改善了我国环境；贸易自由化诱致的经济结构变化有双重环境效应——污染天堂动因的消极环境影响、要素禀赋动因和其他动因的积极环境影响。但自由留易的总环境效应是积极的。

关键词： Antweiler模型环境污染经济规模技术经济结构自由贸易比较优势