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NOTE ON PROJECTION BODIES OF ZONOTOPES WITH n+1 GENERATORS
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作者 Martin HENK 《Acta Mathematica Scientia》 2025年第1期96-103,共8页
We show that the volume of the projection bodyΠ(Z)of an n-dimensional zonotope Z with n+1 generators and of volume 1 is always exactly 2^(n).Moroever,we point out that an upper bound on the volume ofΠ(K)of a central... We show that the volume of the projection bodyΠ(Z)of an n-dimensional zonotope Z with n+1 generators and of volume 1 is always exactly 2^(n).Moroever,we point out that an upper bound on the volume ofΠ(K)of a centrally symmetric n-dimensional convex body of volume 1 is at least 2^(n)(9/8)^([n/3]). 展开更多
关键词 projection body Petty functional POLYTOPES ZONOTOPES
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以Project为成果导向进行单元整体教学--以新版PEP《英语》三年级上册Unit 3 Amazing animals为例
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作者 何玲丽 《教学月刊(小学版)(综合)》 2025年第1期46-49,共4页
新版PEP《英语》增设了Project板块,旨在引导学生通过同伴合作、作品制作、成果交流、活动评价等方式综合运用所学语言知识和技能完成学习任务,展现学习成果,从而培养学生的综合语言运用能力、开放性思维能力和创新意识。为了有效落实... 新版PEP《英语》增设了Project板块,旨在引导学生通过同伴合作、作品制作、成果交流、活动评价等方式综合运用所学语言知识和技能完成学习任务,展现学习成果,从而培养学生的综合语言运用能力、开放性思维能力和创新意识。为了有效落实教学目标,保证教学效果,教师可以Project为成果导向,在分析教材与学情的基础上制定单元教学目标,完成教学设计,实施教学过程,落实教学评价,初步培养学生的英语学科核心素养。 展开更多
关键词 成果导向 小学英语 新教材 project板块 单元整体
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Differentiation degree combination weighting method for investment decision-making risk assessment in power grid construction projects 被引量:6
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作者 Yuan Chang Chenmiao Liu +4 位作者 Minghua Liu Wenxia Liu Zongqi Liu Heng Zhang Yan Zheng 《Global Energy Interconnection》 2019年第5期466-478,共13页
Power grid construction projects are distinguished by their wide variety,high investment,long payback period,and close relation to national development and human welfare.To improve the investment accuracy in such proj... Power grid construction projects are distinguished by their wide variety,high investment,long payback period,and close relation to national development and human welfare.To improve the investment accuracy in such projects and effectively prevent investment risks,this paper proposes an investment optimization decision-making method for multiple power grid construction projects under a certain investment scale.Firstly,an in-depth analysis of the characteristics and development requirements of China’s power grid projects was performed.Thereafter,the time sequence and holographic method was adopted to conduct multi-dimensional,multi-perspective risk assessment of different parts of power grid projects,and a holographic risk assessment index system was developed.Moreover,an investment decision model considering the comprehensive risk based on combination weighting was developed according to the output and input of power grid construction projects.A new combination weighting optimization method that takes into account the investment willingness of enterprises was designed to improve the current weighting evaluation methods.Finally,the validity and applicability of the proposed evaluation method were verified by case examples. 展开更多
关键词 Power GRID projects Risk assessment Time SEQUENCE Index system Combination weighting
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Risk measurement of international oil and gas projects based on the Value at Risk method 被引量:2
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作者 Cheng Cheng Zhen Wang +1 位作者 Ming-Ming Liu Xiao-Hang Ren 《Petroleum Science》 SCIE CAS CSCD 2019年第1期199-216,共18页
International oil and gas projects feature high capital-intensity, high risks and contract diversity. Therefore, in order to help decision makers make more reasonable decisions under uncertainty, it is necessary to me... International oil and gas projects feature high capital-intensity, high risks and contract diversity. Therefore, in order to help decision makers make more reasonable decisions under uncertainty, it is necessary to measure the risks of international oil and gas projects. For this purpose, this paper constructs a probabilistic model that is based on the traditional economic evaluation model, and introduces value at risk(VaR) which is a valuable risk measure tool in finance, and applies Va R to measure the risks of royalty contracts, production share contracts and service contracts of an international oil and gas project. Besides, this paper compares the influences of different risk factors on the net present value(NPV) of the project by using the simulation results. The results indicate:(1) risks have great impacts on the project's NPV, therefore, if risks are overlooked, the decision may be wrong.(2) A simulation method is applied to simulate the stochastic distribution of risk factors in the probabilistic model. Therefore, the probability is related to the project's NPV, overcoming the inherent limitation of the traditional economic evaluation method.(3) VaR is a straightforward risk measure tool, and can be applied to evaluate the risks of international oil and gas projects. It is helpful for decision making. 展开更多
关键词 RISK measurement Value at RISK INTERNATIONAL oil and gas projects FISCAL TERMS - Probabilistic model
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Risk assessment:method and case study for traffic projects 被引量:2
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作者 Xin Yu Panos D.Prevedouros 《Journal of Modern Transportation》 2017年第4期236-249,共14页
A comprehensive project evaluation and decision-making method considering multiple objectives,stakeholders,and attributes of proposed traffic treatments is inherently complicated.Although individual techniques in eval... A comprehensive project evaluation and decision-making method considering multiple objectives,stakeholders,and attributes of proposed traffic treatments is inherently complicated.Although individual techniques in evaluating operations,safety,economic,and stakeholder objectives are available,a practical method that integrates all these risk factors and their uncertainties into a multiattribute decision-making tool is absent.A three-level project decision-making process was developed to model and assess multiple-attribute risk in a proposed traffic treatment from the perspective of multiple stakeholders.The direct benefits from reducing delay and safety risk(basic objectives of traffic treatments) are computed in Level 1 with established methods.Feasibility and performance analysis in Level 2 examine site-specific constraints and conduct detailed performance analysis using advanced analysis tools.In Level 3,this paper introduces an innovative and integrated multiple attributes evaluation process under fuzziness and uncertainty(MAFU) process for evaluation and decision-making.The MAFU is a comprehensive and systematic assessment and decision-making procedure that can assess the magnitudes of project performance and to integrate conflicting interests and tradeoffs among stakeholders.A case study illustrates theapplication of MAFU for the selection of a traffic alternative involving several evaluation attributes and stakeholders.Results show that the MAFU produced the smallest variance for each alternative.With traditional cost–benefit evaluation methods,the uncertainty associated with performance of a traffic project in terms of operation,safety,environmental impacts,etc.,is unrestricted and cumulative.Therefore,a reliable multi-attribute evaluation of complex traffic projects should not be made with conventional cost–benefit analysis alone but with a process like MAFU. 展开更多
关键词 Risk assessment UNCERTAINTY Traffic project Monte Carlo Simulation DECISION-MAKING
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A Rework Reduction Mechanism in Complex Projects Using Design Structure Matrix Clustering Methods 被引量:1
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作者 XU Haiyan ZHAO Shinan +1 位作者 Amin MAHMOUDI Mohammad Reza FEYLIZADEH 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2019年第2期264-279,共16页
To reduce the uncertainty and reworks in complex projects,a novel mechanism is systematically developed in this paper based on two classical design structure matrix(DSM)clustering methods:Loop searching method(LSM)and... To reduce the uncertainty and reworks in complex projects,a novel mechanism is systematically developed in this paper based on two classical design structure matrix(DSM)clustering methods:Loop searching method(LSM)and function searching method(FSM).Specifically,the optimal working areas for the two clustering methods are first obtained quantitatively in terms of non-zero fraction(NZF)and singular value modularity index(SMI),in which the whole working area is divided into six sub-zones.Then,a judgement procedure is proposed for conveniently choosing the optimal DSM clustering method,which makes it easy to determine which DSM clustering method performs better for a given case.Subsequently,a conceptual model is constructed to assist project managers in effectively analyzing the network of projects and greatly reducing reworks in complex projects by defining preventive actions.Finally,the aircraft design process is presented to show how the proposed judgement mechanism can be utilized to reduce the reworks in actual projects. 展开更多
关键词 project management design structure MATRIX LOOP SEARCHING METHOD FUNCTION SEARCHING METHOD reworks
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Discussion on Reasonable Supporting Parameters for Repairing Underground Projects in Bulking Soft Rock
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作者 宋宏伟 《International Journal of Mining Science and Technology》 SCIE EI 1999年第1期18-21,共4页
Based on analysis of the supporting object of bulking soft rock and comparing the supporting difficulty of the repairing projects with that of the newly excavated projects, this paper proposes a method to determine re... Based on analysis of the supporting object of bulking soft rock and comparing the supporting difficulty of the repairing projects with that of the newly excavated projects, this paper proposes a method to determine reasonable supporting parameters for soft rock project repairing. This method has been verified to be reasonable and economical in an industrial test. 展开更多
关键词 soft ROCK SUPPORTING SUPPORTING parameter repairing of UNDERGROUND project SUPPORTING mechanism broken ROCK ZONE
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Model of Cost-benefit Flow in Six Green Projects in China
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作者 ZhuYongjie ZhouBoling 《Forestry Studies in China》 CAS 2003年第3期49-53,共5页
From the point of cost-benefit flow and with the Six Green Projects in China as the case and background, it is criticized that the current natural resource and environmental management and the policies in China have s... From the point of cost-benefit flow and with the Six Green Projects in China as the case and background, it is criticized that the current natural resource and environmental management and the policies in China have some problems unsolved since the model of cost-benefit flow is still centralized and mainly in an administrative way in spite of many efforts made theoretically and practically. It is suggested that a new model based on market-oriented economy from the point of cost-benefit flow with Six Green Projects Management and Policies System consist of complete natural reserve (NR). Management system included environmental nature reserves in addition to biodiversity nature reserve, paid using nature resources, an environmental conservation and construction industry and renewable resource production incentive system that turn the direct administration and operation to management and services. The detail figure of the new model of cost-benefit flow is provided and the main points related are discussed in this paper. 展开更多
关键词 Six Green projects model of cost-benefit flow management and policy frame
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Research on Human Resources Localization for Overseas Pipeline Projects-Taking the Indian Project as an Example
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作者 Zhang Huanjie Li Qiang Di Guoqing 《China Oil & Gas》 CAS 2018年第1期25-28,共4页
Given fierce competition in the overseas pipeline project market, human resources localization has become the only way to sustain the development of overseas pipeline projects. Thus, in this paper, the significance of... Given fierce competition in the overseas pipeline project market, human resources localization has become the only way to sustain the development of overseas pipeline projects. Thus, in this paper, the significance of human resources localization is analyzed in terms of the needs of the "going global" strategy, the reduction of labor costs, the aversion of project risks, and project communication. In addition, relevant measures for human resources localization are proposed, taking the Indian project as an example. 展开更多
关键词 OVERSEAS PIPELINE projects Human RESOURCES LOCALIZATION
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A Mathematical Model Based on Supply Chain Optimization for International Petrochemical Engineering Projects
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作者 Gao Ning Sun Wei 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2015年第2期91-100,共10页
Based on the study of supply chain(SC) and SC optimization in engineering projects, a mixed integer nonlinear programming(MINLP) optimization model is developed to minimize the total SC cost for international petroche... Based on the study of supply chain(SC) and SC optimization in engineering projects, a mixed integer nonlinear programming(MINLP) optimization model is developed to minimize the total SC cost for international petrochemical engineering projects. A steam cracking project is selected and analyzed, from which typical SC characteristics in international engineering projects in the area of petrochemical industry are summarized. The MINLP model is therefore developed and applied to projects with detailed data. The optimization results are analyzed and compared by the MINLP model, indicating that they are appropriate to SC management practice in engineering projects, and are consistent with the optimal priceeffective strategy in procurement. As a result, the model could provide useful guidance to SC optimization of international engineering projects in petrochemical industry, and improve SC management by selecting more reliable and qualified partner enterprises in SC for the project. 展开更多
关键词 supply chain OPTIMIZATION MODEL engineering project MINLP
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A multi-level evaluation model for the recognition and assessment of impact factors associated with intercontinental power interconnection projects
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作者 Chen Chen Caihao Liang +3 位作者 Yuanbing Zhou Chen Wang Jing Lu Fei Xu 《Global Energy Interconnection》 2020年第1期31-43,共13页
The construction of intercontinental power grid interconnection projects is key to realizing the vision of Global Energy Interconnection,which is to solve global energy problems in a clean and sustainable manner.These... The construction of intercontinental power grid interconnection projects is key to realizing the vision of Global Energy Interconnection,which is to solve global energy problems in a clean and sustainable manner.These projects may be influenced by a few factors that are neither technological nor economic,such as political,social,and international factors.This paper thus presents a multi-level model for recognizing which factor from a compiled list of 14 would impact a particular intercontinental interconnection project and for assessing the degree of the factor’s influence.In the first part of the model,the Analytic Hierarchy Process(AHP)method is used to recognize the project’s most significant impact factors.Using the recognition results,the second part of the model can assess the degree of the factor’s influence on the project based on ratings provided by experts.A comprehensive evaluation can thus be provided.As a case study,the proposed Saudi Arabia-Ethiopia power grid interconnection project connecting Asia and Africa was analyzed.Derived from a combination of multiple opinions from experts,evaluations from the model will be of direct benefit to decision-makers,investors,project implementers,and engineers,providing them with a deeper insight into the project. 展开更多
关键词 Global energy INTERCONNECTION Intercontinental POWER grid INTERCONNECTION project Impact FACTOR RECOGNITION and ASSESSMENT model
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Bargaining strategy of oil companies in international oil and gas development Projects-Based on a bilateral bargaining model
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作者 Qing Xue Cheng Cheng +1 位作者 Zhen Wang Ming-Ming Liu 《Petroleum Science》 SCIE CAS CSCD 2021年第4期1270-1279,共10页
Bargaining between the host country and oil companies is very common to international oil and gas development projects.The existence of information asymmetry gives the host country an endogenous bargaining advantage.F... Bargaining between the host country and oil companies is very common to international oil and gas development projects.The existence of information asymmetry gives the host country an endogenous bargaining advantage.Foreign oil companies might change their unfavorable negotiating position by changing the order of bidding and adjusting bidding strategies.This paper introduces both factors into a bilateral bargaining model to study the impact of information asymmetry and bidding order on the strategy and equilibrium returns of oil companies.According to the ownership of the right to bid first,two scenarios are designed for the model to compare the equilibrium returns of the host country and oil companies.The results show that:1)There is a first-mover advantage in the process of bilateral bidding,so oil companies better bid first;2)The information asymmetry will lead to a higher nominal income ratio of oil companies and a lower nominal income ratio of the host country,but it doesn’t affect the total income ratio at all. 展开更多
关键词 International oil and gas development project Information asymmetry Cooperation strategy Bilateral bidding model
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Shanghai Huayi Group to Construct and Debottleneck Petrochemical Projects
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《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2005年第4期46-46,共1页
The Shanghai Huayi Group Company plans during the 2006—2010 period to invest 25 billion RMB in Shanghai and otherregions to construct grassroots units or retrofit existing units.Approximately 6.25 billion RMB will be... The Shanghai Huayi Group Company plans during the 2006—2010 period to invest 25 billion RMB in Shanghai and otherregions to construct grassroots units or retrofit existing units.Approximately 6.25 billion RMB will be used to expand andrevamp the projects located in Shanghai Wusong base,in- 展开更多
关键词 Shanghai Huayi Group to Construct and Debottleneck Petrochemical projects
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ECONOMIC ANALYSIS OF GAS-TO-LIQUIDS PROJECTS IN CHINA
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《China Oil & Gas》 CAS 2001年第2期16-19,共4页
关键词 GTL ECONOMIC ANALYSIS OF GAS-TO-LIQUIDS projects IN CHINA GAS
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CPECC Rapid Growth in Contracting Overseas Projects
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作者 Wang Yong and Wand Guoqing (China Petroleum Engineering & Construction (Group) Corporation ) 《China Oil & Gas》 CAS 1999年第1期68-70,共3页
关键词 CPECC Rapid Growth in Contracting Overseas projects In
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GAZ DE FRANCE INVESTMENT IN CHINA's ENERGY PROJECTS
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《China Oil & Gas》 CAS 2000年第2期48-52,共5页
关键词 than more GAZ DE FRANCE INVESTMENT IN CHINA’s ENERGY projects LNG DE
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New Projects[2022.1—2023.7]
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《造纸信息》 2023年第9期101-104,共4页
On January 2^(nd),2022,the PM2 paper machine of Guanyun Limin Renewable Resource Technology Development Co.,Ltd.was successfully put into operation,with a width of 5,200 mm and a design speed of 700 m/min.The annual p... On January 2^(nd),2022,the PM2 paper machine of Guanyun Limin Renewable Resource Technology Development Co.,Ltd.was successfully put into operation,with a width of 5,200 mm and a design speed of 700 m/min.The annual production capacity of PM2 exceeds 200,000 tons,which uses waste paper to produce low-weight cardboard boxes. 展开更多
关键词 BOXES capacity projects
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Quantum block coherence with respect to projective measurements
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作者 王璞 李忠艳 孟会贤 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期213-220,共8页
Quantum coherence serves as a defining characteristic of quantum mechanics,finding extensive applications in quantum computing and quantum communication processing.This study explores quantum block coherence in the co... Quantum coherence serves as a defining characteristic of quantum mechanics,finding extensive applications in quantum computing and quantum communication processing.This study explores quantum block coherence in the context of projective measurements,focusing on the quantification of such coherence.Firstly,we define the correlation function between the two general projective measurements P and Q,and analyze the connection between sets of block incoherent states related to two compatible projective measurements P and Q.Secondly,we discuss the measure of quantum block coherence with respect to projective measurements.Based on a given measure of quantum block coherence,we characterize the existence of maximal block coherent states through projective measurements.This research integrates the compatibility of projective measurements with the framework of quantum block coherence,contributing to the advancement of block coherence measurement theory. 展开更多
关键词 quantum coherence compatibility projective measurement quantum block coherence
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Seven Projects Planned for Huabei Oilfield
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《China Oil & Gas》 CAS 1997年第2期127-127,共1页
关键词 Seven projects Planned for Huabei Oilfield
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REFINEMENTS OF THE NORM OF TWO ORTHOGONAL PROJECTIONS
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作者 Xiaohui LI Meiqi LIU Chunyuan DENG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1229-1243,共15页
In this paper,some refinements of norm equalities and inequalities of combination of two orthogonal projections are established.We use certain norm inequalities for positive contraction operator to establish norm ineq... In this paper,some refinements of norm equalities and inequalities of combination of two orthogonal projections are established.We use certain norm inequalities for positive contraction operator to establish norm inequalities for combination of orthogonal projections on a Hilbert space.Furthermore,we give necessary and sufficient conditions under which the norm of the above combination of o`rthogonal projections attains its optimal value. 展开更多
关键词 NORM orthogonal projection positive operator SPECTRAL block operator valued matrix
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