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Almost Stochastic Dominance and Efficient Investment Sets 被引量:1
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作者 Moshe Levy 《American Journal of Operations Research》 2012年第3期313-321,共9页
A major drawback of Mean-Variance and Stochastic Dominance investment criteria is that they may fail to determine dominance even in situations when all “reasonable” decision-makers would clearly prefer one alternati... A major drawback of Mean-Variance and Stochastic Dominance investment criteria is that they may fail to determine dominance even in situations when all “reasonable” decision-makers would clearly prefer one alternative over another. Leshno and Levy [1] suggest Almost Stochastic Dominance (ASD) as a remedy. This paper develops algorithms for deriving the ASD efficient sets. Empirical application reveals that the improvement to the efficient sets implied by ASD is substantial (64% reduction for FSD). Direct expected utility maximization shows that investment portfolios excluded from the ASD efficient set would not have been chosen by any investors with reasonable preferences. 展开更多
关键词 Stochastic DOMINANCE efficient INVESTMENT set INVESTMENT CHOICE
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Unique Efficient Dominating Sets
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作者 Isaac Reiter Ju Zhou 《Open Journal of Discrete Mathematics》 2020年第2期56-68,共13页
Given a finite simple graph G, a set D &#8838;V(G) is called a dominating set if for all v ∈ V(G) , either v ∈ D or v is adjacent to some vertex in D. A dominating set D is independent if none of the vertices in... Given a finite simple graph G, a set D &#8838;V(G) is called a dominating set if for all v ∈ V(G) , either v ∈ D or v is adjacent to some vertex in D. A dominating set D is independent if none of the vertices in D are adjacent, and D is perfect if each vertex not in D is adjacent to precisely one vertex in D. If a dominating set is both independent and perfect, then it is called an efficient dominating set. For a graph G, a set D is called a unique efficient dominating set of G if it is the only efficient dominating set of G. In this paper, the authors propose the definition of unique efficient dominating set, explore the properties of graphs with unique efficient dominating sets, and completely characterize several families of graphs which have unique efficient dominating sets. 展开更多
关键词 Dominating set Minimum Dominating set efficient Dominating set UNIQUE efficient Dominating set
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An Efficient Class of Estimators for the Finite Population Mean in Ranked Set Sampling
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作者 Lakhkar Khan Javid Shabbir 《Open Journal of Statistics》 2016年第3期426-435,共10页
In this paper, we propose a class of estimators for estimating the finite population mean of the study variable under Ranked Set Sampling (RSS) when population mean of the auxiliary variable is known. The bias and Mea... In this paper, we propose a class of estimators for estimating the finite population mean of the study variable under Ranked Set Sampling (RSS) when population mean of the auxiliary variable is known. The bias and Mean Squared Error (MSE) of the proposed class of estimators are obtained to first degree of approximation. It is identified that the proposed class of estimators is more efficient as compared to [1] estimator and several other estimators. A simulation study is carried out to judge the performances of the estimators. 展开更多
关键词 Ranked set Sampling Auxiliary Variable BIAS Mean Squared Error Relative efficiency
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To Set up an Efficient,Clean and Commerce-oriented Local Government--An Interview With Mr.Chen Deming,Mayor of Suzhou City
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作者 WangZheng HanDaqing 《China's Foreign Trade》 2000年第4期7-9,共3页
关键词 An Interview With Mr.Chen Deming Mayor of Suzhou City To set up an efficient Clean and Commerce-oriented Local Government
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ENERGY-EFFICIENT HEURISTIC METRIC FOR SCP IN SENSOR NETWORKS
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作者 黄如 朱杰 徐光辉 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第1期51-60,共10页
A heuristic metric is presented to achieve the optimal connected set covering problem (SCP) in sensor networks. The coverage solution with the energy efficiency can guarantee that all targets are fully covered. Amon... A heuristic metric is presented to achieve the optimal connected set covering problem (SCP) in sensor networks. The coverage solution with the energy efficiency can guarantee that all targets are fully covered. Among targets, the crucial ones are redundantly covered to ensure more reliable monitors. And the information collected by the above coverage solution can be transmitted to Sink by the connected data-gathering structure. A novel ant colony optimization (ACO) algorithm--improved-MMAS-ACS-hybrid algorithm (IMAH) is adopted to achieve the above metric. Based on the design of the heuristic factor, artificial ants can adaptively detect the coverage and energy status of sensor networks and find the low-energy-cost paths to keep the communication connectivity to Sink. By introducing the pheromone-judgment-factor and the evaluation function to the pheromone updating rule, the pheromone trail on the global-best solution is enhanced, while avoiding the premature stagnation. Finally, the energy efficiency set can be obtained with high coverage-efficiency to all targets and reliable connectivity to Sink and the lifetime of the connected coverage set is prolonged. 展开更多
关键词 sensor networks energy efficiency set covering problem (SCP) CONNECTIVITY ant colony optimization
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Efficient Mass Transport and Electrochemistry Coupling Scheme for Reliable Multiphysics Modeling of Planar Solid Oxide Fuel Cell Stack
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作者 李昂 林子敬 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2017年第2期139-146,I0001,共9页
A multiphysics model for a production scale planar solid oxide fuel cell (SOFC) stack is important for the SOFC technology, but usually requires an unpractical amount of computing resource. The major cause for the h... A multiphysics model for a production scale planar solid oxide fuel cell (SOFC) stack is important for the SOFC technology, but usually requires an unpractical amount of computing resource. The major cause for the huge computing resource requirement is identified as the need to solve the cathode O2 transport and the associated electrochemistry. To overcome the technical obstacle, an analytical model for solving the O2 transport and its coupling with the electrochemistry is derived. The analytical model is used to greatly reduce the numerical mesh complexity of a multiphysics model. Numerical test shows that the analytical approximation is highly accurate and stable. A multiphysics numerical modeling tool taking advantage of the analytical solution is then developed through Fluent@. The numerical efficiency and stability of this modeling tool are further demonstrated by simulating a 30- cell stack with a production scale cell size. Detailed information about the stack performance is revealed and briefly discussed. The multiphysics modeling tool can be used to guide the stack design and select the operating parameters. 展开更多
关键词 Simulation Mesh setting Analytical model Computational efficiency Numerical stability
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On super efficiency in set-valued optimization 被引量:3
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作者 LI Tai-yong XU Yi-hong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2009年第2期144-150,共7页
The set-valued optimization problem with constraints is considered in the sense of super efficiency in locally convex linear topological spaces. Under the assumption of iccone-convexlikeness, by applying the seperatio... The set-valued optimization problem with constraints is considered in the sense of super efficiency in locally convex linear topological spaces. Under the assumption of iccone-convexlikeness, by applying the seperation theorem, Kuhn-Tucker's, Lagrange's and saddle points optimality conditions, the necessary conditions are obtained for the set-valued optimization problem to attain its super efficient solutions. Also, the sufficient conditions for Kuhn-Tucker's, Lagrange's and saddle points optimality conditions are derived. 展开更多
关键词 super efficiency IC-CONE-CONVEXLIKENESS set-valued optimization saddle point
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ON THE GENERALIZED FRITZ JOHN OPTIMALITY CONDITIONS OF VECTOR OPTIMIZATION WITH SET-VALUED MAPS UNDER BENSON PROPER EFFICIENCY 被引量:3
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作者 盛宝怀 刘三阳 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第12期1444-1451,共8页
A kind of tangent derivative and the concepts of strong and weak * pseudoconvexity for a set-valued map are introduced. By the standard separation theorems of the convex sets and cones the optimality Fritz John condit... A kind of tangent derivative and the concepts of strong and weak * pseudoconvexity for a set-valued map are introduced. By the standard separation theorems of the convex sets and cones the optimality Fritz John condition of set-valued optimization under Benson proper efficiency is established, its sufficience is discussed. The form of the optimality conditions obtained here completely tally with the classical results when the set-valued map is specialized to be a single-valued map. 展开更多
关键词 contingent tangent cone set-valued map Benson proper efficiency Fritz John condition
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Benson proper efficiency for vector optimization of generalized subconvexlike set-valued maps in ordered linear spaces 被引量:2
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作者 周志昂 《Journal of Shanghai University(English Edition)》 CAS 2010年第5期374-379,共6页
Several equivalent statements of generalized subconvexlike set-valued map are established in ordered linear spaces. Using vector closure, we introduce Benson proper efficient solution of vector optimization problem. U... Several equivalent statements of generalized subconvexlike set-valued map are established in ordered linear spaces. Using vector closure, we introduce Benson proper efficient solution of vector optimization problem. Under the assumption of generalized subconvexlikeness, scalarization, multiplier and saddle point theorems are obtained in the sense of Benson proper efficiency. 展开更多
关键词 set-valued maps vector closure generalized subconvexlikeness Benson proper efficient solution
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On the Coalitional Rationality of the Shapley Value and Other Efficient Values of Cooperative TU Games
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作者 Irinel Dragan 《American Journal of Operations Research》 2014年第4期228-234,共7页
In the theory of cooperative transferable utilities games, (TU games), the Efficient Values, that is those which show how the win of the grand coalition is shared by the players, may not be a good solution to give a f... In the theory of cooperative transferable utilities games, (TU games), the Efficient Values, that is those which show how the win of the grand coalition is shared by the players, may not be a good solution to give a fair outcome to each player. In an earlier work of the author, the Inverse Problem has been stated and explicitely solved for the Shapley Value and for the Least Square Values. In the present paper, for a given vector, which is the Shapley Value of a game, but it is not coalitional rational, that is it does not belong to the Core of the game, we would like to find out a new game with the Shapley Value equal to the a priori given vector and for which this vector is also in the Core of the game. In other words, in the Inverse Set relative to the Shapley Value, we want to find out a new game, for which the Shapley Value is coalitional rational. The results show how such a game may be obtained, and some examples are illustrating the technique. Moreover, it is shown that beside the original game, there are always other games for which the given vector is not in the Core. The similar problem is solved for the Least Square Values. 展开更多
关键词 efficiency Shapley Value Coalitional RATIONALITY Least SQUARE VALUES INVERSE Problem INVERSE set
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Well-Posedness for Tightly Proper Efficiency in Set-Valued Optimization Problem
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作者 Yangdong Xu Pingping Zhang 《Advances in Pure Mathematics》 2011年第4期184-186,共3页
In this paper, a characterization of tightly properly efficient solutions of set-valued optimization problem is obtained. The concept of the well-posedness for a special scalar problem is linked with the tightly prope... In this paper, a characterization of tightly properly efficient solutions of set-valued optimization problem is obtained. The concept of the well-posedness for a special scalar problem is linked with the tightly properly efficient solutions of set-valued optimization problem. 展开更多
关键词 set-VALUED OPTIMIZATION PROBLEM Tightly PROPER efficiENCY WELL-POSEDNESS
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Optimality for Henig Proper Efficiency in Vector Optimization Involving Dini Set-Valued Directional Derivatives
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作者 Guolin Yu Huaipeng Bai 《Applied Mathematics》 2011年第7期922-925,共4页
This note studies the optimality conditions of vector optimization problems involving generalized convexity in locally convex spaces. Based upon the concept of Dini set-valued directional derivatives, the necessary an... This note studies the optimality conditions of vector optimization problems involving generalized convexity in locally convex spaces. Based upon the concept of Dini set-valued directional derivatives, the necessary and sufficient optimality conditions are established for Henig proper and strong minimal solutions respectively in generalized preinvex vector optimization problems. 展开更多
关键词 VECTOR Optimization Dini set-VALUED Directional DERIVATIVE Generalized Preinvex Function Henig PROPER efficiency
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组态视角下减污降碳政策工具对环境规制效率的驱动机制——基于中国30个省份的fsQCA实证分析
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作者 孙钰 宋雪瑶 +2 位作者 马建辉 齐艳芬 姚鹏 《资源开发与市场》 CAS 2024年第3期355-365,共11页
减污降碳是环境规制效率提升的标志,是实现污染控制和环境质量改善的重要抓手和突破口,探究减污降碳政策工具驱动环境规制效率提升的内在机理,对于推进“双碳”目标实现具有重要意义。以2012—2022年中国30个省份数据为研究对象,借助模... 减污降碳是环境规制效率提升的标志,是实现污染控制和环境质量改善的重要抓手和突破口,探究减污降碳政策工具驱动环境规制效率提升的内在机理,对于推进“双碳”目标实现具有重要意义。以2012—2022年中国30个省份数据为研究对象,借助模糊集定性比较分析法(fsQCA)探析命令控制型、市场激励型和自愿参与型政策工具促进环境规制效率提升的多元路径组合。结果发现:减污降碳政策工具在提升全国环境规制效率方面呈现4种组合模式,且分别与中国东、中、西部地区的实施效果相匹配,未来将呈现多元政策工具组合协同发力的态势;命令控制型政策工具在提升中西部地区环境规制效率中发挥主导作用,中部地区尤为明显;自愿参与型工具则更多依赖命令控制型、市场激励型工具发挥政策组合作用,在西部地区发挥效力较弱。不同的环境规制效率驱动效果会带来差异化的政策工具组合,以此为不同地区提供政策建议。 展开更多
关键词 减污降碳 政策工具 环境规制效率 模糊集定性比较分析
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多院区医院床位效能优化评测实践与探索
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作者 卢瑶 梁丽红 +1 位作者 蒋小花 吴玲红 《医院管理论坛》 2024年第8期41-44,共4页
目的科学合理设置病房布局和规模,实现床位效能最优化。方法选取医院2022年住院统计报表及DRG相关数据,包括出院人次、实际占用床日数、床位使用率、病床周转次数等。运用指数分布图将全院病区分为四类,建立床位工作效率模型和病床产出... 目的科学合理设置病房布局和规模,实现床位效能最优化。方法选取医院2022年住院统计报表及DRG相关数据,包括出院人次、实际占用床日数、床位使用率、病床周转次数等。运用指数分布图将全院病区分为四类,建立床位工作效率模型和病床产出效率模型,并引入CMI指标进行调整。结果医院有40%的病区位于“效率型”象限,5.3%位于“压床型”象限,28%位于“周转型”象限,26.7%位于“空置型”象限。经CMI调整后的病床产出效率、病区布局显著改善,实现了资源的优化配置。结论通过床位工作效率和病床产出效率进行床位合理区间估算,结合实际情况进行适时床位调整和人员调配,有效提升了医院运营效率。 展开更多
关键词 医院 床位效能 多院区管理 病房配置
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陕西科技成果转化效率影响因素组态效应研究
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作者 王育晓 阳一文 王霞 《西安工业大学学报》 CAS 2024年第1期117-126,共10页
为提升科技成果转化效率,促进创新型国家转型和陕西经济高质量发展。文中基于整合视角,运用因子分析法和模糊集定性比较法从制度、组织和资源三个层面探究陕西科技成果转化效率影响因素的组态效应。研究结果发现:单一层面的因素难以决... 为提升科技成果转化效率,促进创新型国家转型和陕西经济高质量发展。文中基于整合视角,运用因子分析法和模糊集定性比较法从制度、组织和资源三个层面探究陕西科技成果转化效率影响因素的组态效应。研究结果发现:单一层面的因素难以决定科技成果转化效率的高低;身份自洽下政策协调型、中介实力下政策供给型、身份自洽下技术资源型是实现陕西科技成果转化高效率的3种组态类型,其中身份自洽在产生科技成果转化高效率上发挥关键作用;组织要素在一定情景下可以弥补政策供给的缺失,组织要素内部的机构实力和身份自洽在一定情景下可以相互替代。研究结论可以为优化陕西科技成果转化政策、促进陕西科技成果高效转化提供专业参考。 展开更多
关键词 科技成果 转化效率 模糊集定性比较 组态效应 整合视角
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二层多目标随机规划逼近弱有效解集的上半收敛性
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作者 周婉娜 霍永亮 《纺织高校基础科学学报》 CAS 2024年第3期118-124,共7页
为研究二层多目标随机规划逼近问题的弱有效解与精确的弱有效解之间的逼近收敛性,针对上、下层都带有约束条件的一类多目标二层随机规划的逼近问题,构建了二层多目标随机规划逼近问题的弱有效解集的上半收敛性理论框架。即在假设下层反... 为研究二层多目标随机规划逼近问题的弱有效解与精确的弱有效解之间的逼近收敛性,针对上、下层都带有约束条件的一类多目标二层随机规划的逼近问题,构建了二层多目标随机规划逼近问题的弱有效解集的上半收敛性理论框架。即在假设下层反馈到上层的最优解集函数为凸函数的前提下,借助严格凸函数的性质,利用多目标随机规划的弱有效解可以表示成相应的单目标随机规划最优解集交集的结构特征,建立了二层多目标随机规划逼近弱有效解集的上半收敛性,提供了逼近方法求解二层多目标随机规划弱有效解集可以近似替代精确的弱有效解集的理论依据。 展开更多
关键词 单目标随机规划 多目标随机规划 弱有效解集 严格凸函数
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基于Rasch模型的船舶舾装效率影响要素分析
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作者 李晓萍 杨倩 张辉 《船舶工程》 CSCD 北大核心 2024年第5期129-137,共9页
针对现有提高舾装效率的研究局限于某一环节,缺乏全面系统性分析,难以客观准确评价各因素影响程度的问题,基于实地考察、专家访谈、问卷调查等方法,综合考虑舾装作业离散型特征,从策划和实施2个阶段分析涉及设计、设备、计划以及人机料... 针对现有提高舾装效率的研究局限于某一环节,缺乏全面系统性分析,难以客观准确评价各因素影响程度的问题,基于实地考察、专家访谈、问卷调查等方法,综合考虑舾装作业离散型特征,从策划和实施2个阶段分析涉及设计、设备、计划以及人机料法环等8个方面的38个影响舾装效率的因素,采用Vague集-熵权法进行主客观评估,筛选出28个关键因素,并采用Rasch模型方法对影响舾装效率的多重要素进行影响程度定量分析。研究发现:策划阶段对舾装效率的影响程度较大,其中因不可控要素供应链受阻是影响最大的要素。研究表明企业应对策划阶段重点改进;实施阶段对舾装效率影响较小,企业无需投入过多资源改进。 展开更多
关键词 舾装效率 影响要素 Vague集-熵权法 RASCH模型
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组态视角下中国体育产业效率提升路径研究——基于29个省份的模糊集定性比较分析
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作者 王兆红 李静 +1 位作者 郭恩恺 许寒冰 《武汉体育学院学报》 CSSCI 北大核心 2024年第10期40-48,共9页
提升体育产业效率是实现体育产业高质量发展的必然要求。采用DEA-BCC模型测度2013-2021年29个省份体育产业效率,并以2021年我国体育产业效率值作为结果变量,从市场环境、产业基础、创新驱动、政策支持4个方面选取7个因素作为前因变量,... 提升体育产业效率是实现体育产业高质量发展的必然要求。采用DEA-BCC模型测度2013-2021年29个省份体育产业效率,并以2021年我国体育产业效率值作为结果变量,从市场环境、产业基础、创新驱动、政策支持4个方面选取7个因素作为前因变量,采用模糊集定性比较分析法(fsQCA)进行分析。结果表明:实现体育产业高效率需要充分发挥多条件联动优势。存在3条提升我国体育产业效率的路径,即“市场环境”带动型路径、“产业基础”主导下的双轮驱动型路径、“产业基础+创新驱动+政策支持”多元联动型路径。基于此,提出了强化体育市场主体功能,提升资源配置效率;落实体育区域发展战略,夯实体育产业基础;遵循因地制宜原则,走差异化竞争之路等建议。 展开更多
关键词 体育产业效率 提升路径 组态视角 模糊集定性比较分析
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叶片安放角对微型轴流式水轮机性能的影响
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作者 杨孙圣 赵尔策 孔祥序 《排灌机械工程学报》 CSCD 北大核心 2024年第4期350-357,共8页
为探究叶片安放角对微型轴流式水轮机水力性能的影响,以一比转数为548的微型轴流式水轮机为研究对象,在不改变其他几何参数的前提下,仅偏置转轮叶片各翼型剖面,得到7个不同叶片安放角的转轮;在试验验证的基础上,通过全流场数值计算,分... 为探究叶片安放角对微型轴流式水轮机水力性能的影响,以一比转数为548的微型轴流式水轮机为研究对象,在不改变其他几何参数的前提下,仅偏置转轮叶片各翼型剖面,得到7个不同叶片安放角的转轮;在试验验证的基础上,通过全流场数值计算,分析了改变叶片安放角对微型轴流式水轮机水力性能的影响.结果表明:随着叶片安放角的减小,在相同流量下水轮机的水头与出力均增大,高效率区域向小流量区域偏移,水轮机可高效运转的范围有一定程度的增大;随着叶片安放角的增大,水轮机的水头与出力减小,高效率区域向大流量区域偏移.适当减小叶片安放角的水轮机能在较大水头(流量)变化范围内维持较好的性能.其中,安放角为-4°的水轮机最高效率达到82.13%,高效率区的范围最大.该研究可为微型轴流式水轮机转轮的设计提供一定参考. 展开更多
关键词 微型轴流式水轮机 叶片安放角 数值计算 水力性能 高效率区
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海外油气效益产量“二步决策法”研究及应用
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作者 李婷 《工程科学学报》 EI CSCD 北大核心 2024年第6期1161-1168,共8页
海外油气项目具有投入大、风险大、回收期长等特点,开展效益产量决策方法研究对提升石油公司整体经营实力、提高抗风险能力举足轻重.本文旨在建立一套系统全面的效益产量经营决策方法,通过抓准项目效益影响因素,构建基于全局满意解集的... 海外油气项目具有投入大、风险大、回收期长等特点,开展效益产量决策方法研究对提升石油公司整体经营实力、提高抗风险能力举足轻重.本文旨在建立一套系统全面的效益产量经营决策方法,通过抓准项目效益影响因素,构建基于全局满意解集的效益产量“二步决策法”,实现一套“可全面可聚焦”的系统决策优选技术模型,最终以优选出的组合作为效益产量推荐方案,助推海外油气资产保值增值.本文创建的海外油气效益产量“二步决策法”,在国内某石油公司海外业务板块近4年的油气资产生产经营中取得了较好的应用效果,为该石油公司海外油气资产提效增效和高质量发展提供了可靠的技术支持.该方法也同样适用于国内上游油气开发板块效益产量优化决策,值得借鉴及推广. 展开更多
关键词 海外油气 效益产量 二步决策法 全局满意解集模型 最优解优选技术
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