期刊文献+
共找到1,361篇文章
< 1 2 69 >
每页显示 20 50 100
MAJOR-EFFICIENT SOLUTIONS AND WEAKLY MAJOR-EFFICIENT SOLUTIONS OF MULTIOBJECTIVE PROGRAMMING 被引量:12
1
作者 HU YUDA(Dept.of Appl.Math.,Shanghai Jiao Tony Univ.,Shanghai 200030) 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1994年第1期85-94,共10页
In this papert the theory of major efficiency for multiobjective programmingis established.The major-efficient solutions and weakly major-efficient solutions of multiobjective programming given here are Pareto efficie... In this papert the theory of major efficiency for multiobjective programmingis established.The major-efficient solutions and weakly major-efficient solutions of multiobjective programming given here are Pareto efficient solutions of the same multiobjectiveprogramming problem, but the converse is not true. In a ceratin sense , these solutionsare in fact better than any other Pareto efficient solutions. Some basic theorems whichcharacterize major-efficient solutions and weakly major-efficient solutions of multiobjective programming are stated and proved. Furthermore,the existence and some geometricproperties of these solutions are studied. 展开更多
关键词 Multiobjective Programming Pareto efficient solution Major-efficientsolution Weakly Major-efficient solution.
在线阅读 下载PDF
CHARACTERIZATION OF EFFICIENT SOLUTIONS FOR MULTI-OBJECTIVE OPTIMIZATION PROBLEMS INVOLVING SEMI-STRONG AND GENERALIZED SEMI-STRONG E-CONVEXITY 被引量:5
2
作者 E.A.Youness Tarek Emam 《Acta Mathematica Scientia》 SCIE CSCD 2008年第1期7-16,共10页
The authors of this article are interested in characterization of efficient solutions for special classes of problems. These classes consider semi-strong E-convexity of involved functions. Sufficient and necessary con... The authors of this article are interested in characterization of efficient solutions for special classes of problems. These classes consider semi-strong E-convexity of involved functions. Sufficient and necessary conditions for a feasible solution to be an efficient or properly efficient solution are obtained. 展开更多
关键词 Multi-objective optimization problems semi-strong E-convex efficient solutions properly efficient solutions
在线阅读 下载PDF
ε-strongly Efficient Solutions for Vector Optimization with Set-valued Maps 被引量:10
3
作者 WANG Qi-liu 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第1期104-109,共6页
In locally convex Hausdorff topological vector spaces,ε-strongly efficient solutions for vector optimization with set-valued maps are discussed.Firstly,ε-strongly efficient point of set is introduced.Secondly,under ... In locally convex Hausdorff topological vector spaces,ε-strongly efficient solutions for vector optimization with set-valued maps are discussed.Firstly,ε-strongly efficient point of set is introduced.Secondly,under the nearly cone-subconvexlike set-valued maps,the theorem of scalarization for vector optimization is obtained.Finally,optimality conditions of ε-strongly efficient solutions for vector optimization with generalized inequality constraints and equality constraints are obtained. 展开更多
关键词 vector optimization ε-strongly efficient point nearly cone-subconvexlike setvalued maps ε-strongly efficient solutions the theorem of scalarization optimality conditions
在线阅读 下载PDF
EXISTENCE RESULTS FOR GLOBALLY EFFICIENT SOLUTIONS OF VECTOR EQUILIBRIUM PROBLEMS VIA A GENERALIZED KKM PRINCIPLE 被引量:1
4
作者 Adela CAPATA 《Acta Mathematica Scientia》 SCIE CSCD 2017年第2期463-476,共14页
The aim of this article is to present new existence results for globally efficient solutions of a strong vector equilibrium problem given by a sum of two functions via a generalized KKM principle, and to establish the... The aim of this article is to present new existence results for globally efficient solutions of a strong vector equilibrium problem given by a sum of two functions via a generalized KKM principle, and to establish the connectedness of the solutions set. 展开更多
关键词 KKM principle equilibrium problems given by a sum globally efficient solution near C-subconvexlikeness
在线阅读 下载PDF
Efficient Solution to Electromagnetic Scattering Problems of Bodies of Revolution by Compressive Sensing 被引量:1
5
作者 孔勐 陈明生 +2 位作者 张量 曹欣远 吴先良 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第1期136-139,共4页
Under the theory structure of compressive sensing (CS), an underdetermined equation is deduced for describing the discrete solution of the electromagnetic integral equation of body of revolution (BOR), which will ... Under the theory structure of compressive sensing (CS), an underdetermined equation is deduced for describing the discrete solution of the electromagnetic integral equation of body of revolution (BOR), which will result in a small-scale impedance matrix. In the new linear equation system, the small-scale impedance matrix can be regarded as the measurement matrix in CS, while the excited vector is the measurement of unknown currents. Instead of solving dense full rank matrix equations by the iterative method, with suitable sparse representation, for unknown currents on the surface of BOR, the entire current can be accurately obtained by reconstructed algorithms in CS for small-scale undetermined equations. Numerical results show that the proposed method can greatly improve the computgtional efficiency and can decrease memory consumed. 展开更多
关键词 of in IS on by BOR efficient solution to Electromagnetic Scattering Problems of Bodies of Revolution by Compressive Sensing
原文传递
Generating Efficient Solutions in Bilevel Multi-Objective Programming Problems
6
作者 Calice Olivier Pieume Patrice Marcotte +1 位作者 Laure Pauline Fotso Patrick Siarry 《American Journal of Operations Research》 2013年第2期289-298,共10页
In this paper, we address bilevel multi-objective programming problems (BMPP) in which the decision maker at each level has multiple objective functions conflicting with each other. Given a BMPP, we show how to constr... In this paper, we address bilevel multi-objective programming problems (BMPP) in which the decision maker at each level has multiple objective functions conflicting with each other. Given a BMPP, we show how to construct two artificial multiobjective programming problems such that any point that is efficient for both the two problems is an efficient solution of the BMPP. Some necessary and sufficient conditions for which the obtained result is applicable are provided. A complete procedure of the implementation of an algorithm for generating efficient solutions for the linear case of BMPP is presented. A numerical example is provided to illustrate how the algorithm operates. 展开更多
关键词 MULTI-OBJECTIVE PROGRAMMING Bilevel PROGRAMMING efficient solution efficient EDGE HIERARCHICAL Systems
在线阅读 下载PDF
An Efficient Accurate Direct Solution of Poisson's Equation for Computation of Meteorological Parameters
7
作者 D.R.Chakraborty P.S.Salvekar 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1989年第4期501-508,共8页
Poisson's equation is solved numerically by two direct methods, viz. Block Cyclic Reduction (BCR) method and Fourier Method. Qualitative and quantitative comparison between the numerical solutions obtained by two ... Poisson's equation is solved numerically by two direct methods, viz. Block Cyclic Reduction (BCR) method and Fourier Method. Qualitative and quantitative comparison between the numerical solutions obtained by two methods indicates that BCR method is superior to Fourier method in terms of speed and accuracy. Therefore. BCR method is applied to solve (?)2(?)= ζ and (?)2X= D from observed vorticity and divergent values. Thereafter the rotational and divergent components of the horizontal monsoon wind in the lower troposphere are reconstructed and are com pared with the results obtained by Successive Over-Relaxation (SOR) method as this indirect method is generally in more use for obtaining the streamfunction ((?)) and velocity potential (X) fields in NWP models. It is found that the results of BCR method are more reliable than SOR method. 展开更多
关键词 An efficient Accurate Direct solution of Poisson’s Equation for Computation of Meteorological Parameters
在线阅读 下载PDF
Effect of polymer solution structure on displacement efficiency 被引量:9
8
作者 Shi Leiting Chen Lei +4 位作者 Ye Zhongbin Zhou Wei Zhang Jian Yang Jie Jin Jianbo 《Petroleum Science》 SCIE CAS CSCD 2012年第2期230-235,共6页
In this paper, a series of experiments, including atomic force microscope (AFM), environmental scanning electron microscope (ESEM), and core displacement tests were conducted to investigate the effect of polymer s... In this paper, a series of experiments, including atomic force microscope (AFM), environmental scanning electron microscope (ESEM), and core displacement tests were conducted to investigate the effect of polymer solution structure on solution properties and oil displacement efficiency. The results show that in the HPAM solution polymer coils were formed and then aggregated into a loose structure, while the HAP2010 solution formed a strong network structure, which would significantly improve the solution viscosity and flow resistance so as to upgrade the capacity of piston-like oil displacement in highly permeable porous media. Meanwhile, the retention of the HAP2010 solution at pore throats were also enhanced, which could reduce water production during subsequent water flooding and enlarge the swept volume during polymer flooding. Therefore, enhancing the interaction among polymer molecules is an effective way to improve the displacement efficiency of polymer solutions in heavy oil reservoirs with high permeability. 展开更多
关键词 POLYMER solution structure loosely-aggregated structure network structure displacement efficiency
原文传递
Reasons and Solutions of the Time-consuming College English Teaching with Low Efficiency
9
作者 刘荣臻 王晓静 《海外英语》 2016年第9期236-237,共2页
College English teaching has been regarded as time- consuming with low efficiency for a long time. This thesis proceeds with the entity of English education in China, deals with the main problems lying in the current ... College English teaching has been regarded as time- consuming with low efficiency for a long time. This thesis proceeds with the entity of English education in China, deals with the main problems lying in the current college English teaching from 3 perspectives, including the nation and society, teachers, and students, and provides 5 suggestions accordingly. 展开更多
关键词 COLLEGE English class teaching time-consuming with low efficiency REASON solution
在线阅读 下载PDF
Crystallization behaviors of bayerite from sodium chromate alkali solutions 被引量:2
10
作者 魏广叶 曲景奎 +4 位作者 郑裕东 齐涛 郭强 韩冰冰 赵宏欣 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第10期3356-3365,共10页
In order to clean production of chromium compounds, it is a critical process to remove aluminates and utilize aluminum compounds from artificial chromate alkali solutions. The effects of Na2 Cr O4 on the neutralizatio... In order to clean production of chromium compounds, it is a critical process to remove aluminates and utilize aluminum compounds from artificial chromate alkali solutions. The effects of Na2 Cr O4 on the neutralization curve, Al(OH)3 precipitation efficiency and induction period of bayerite were investigated. The results indicate that the neutralization curve of the artificial chromate alkali solutions shows three distinct regions and its induction period is longer than that of pure sodium aluminate solutions at the same aluminum concentration. And the decreased temperature and volume fraction of CO2 enhance the particle size of bayerite β-Al(OH)3. Bayerite composed of agglomerates of rods and cone frustums was obtained from alkali metal chromate solutions with 28.5% CO2(volume fraction) at temperatures ranging from 50 °C to 70 °C. Coarse bayerite with particle size(d50) from 24.2 μm to 29.3 μm extremely has few impurities, which is suitable for comprehensive utilization. 展开更多
关键词 chromate alkali solutions BAYERITE CARBONIZATION CRYSTALLIZATION precipitation efficiency
在线阅读 下载PDF
Efficient Authentication Scheme for UAV-Assisted Mobile Edge Computing
11
作者 Maryam Alhassan Abdul Raouf Khan 《Computers, Materials & Continua》 SCIE EI 2023年第5期2727-2740,共14页
Preserving privacy is imperative in the new unmanned aerial vehicle(UAV)-assisted mobile edge computing(MEC)architecture to ensure that sensitive information is protected and kept secure throughout the communication.S... Preserving privacy is imperative in the new unmanned aerial vehicle(UAV)-assisted mobile edge computing(MEC)architecture to ensure that sensitive information is protected and kept secure throughout the communication.Simultaneously,efficiency must be considered while developing such a privacy-preserving scheme because the devices involved in these architectures are resource constrained.This study proposes a lightweight and efficient authentication scheme for theUAV-assistedMECenvironment.The proposed scheme is a hardware-based password-less authentication mechanism that is based on the fact that temporal and memory-related efficiency can be significantly improved while maintaining the data security by adopting a hardwarebased solution with a simple implementation.The proposed scheme works in four stages:system initialization,EU registration,EU authentication,and session establishment.It is implemented as a single hardware chip comprising registers and XOR gates,and it can run the entire process in one clock cycle.Consequently,the proposed scheme has significantly higher efficiency in terms of runtime and memory consumption compared to other prevalent methods in the area.Simulations are conducted to evaluate the proposed authentication algorithm.The results show that the scheme has an average execution time of 0.986 ms and consumes average memory of 34 KB.The hardware execution time is approximately 0.39 ns,which is a significantly less than the prevalent schemes,whose execution times range in milliseconds.Furthermore,the security of the proposed scheme is examined,and it is resistant to brute-force attacks.Around 1.158×10^(77) trials are required to overcome the system’s security,which is not feasible using fastest available processors. 展开更多
关键词 MEC UAVS DRONES security efficiency AUTHENTICATION hardware-based solution password-less authentication
在线阅读 下载PDF
圆柱立铣刀螺旋槽磨削接触线建模与高效数值解法
12
作者 游明琳 刘富毅 张继 《制造技术与机床》 北大核心 2026年第1期183-190,共8页
圆柱立铣刀螺旋槽的精密磨削是其制造过程中的关键环节,精确建立磨削接触线模型对提升刀具加工质量与效率具有重要意义。文章针对现有接触线方程通用性不足与数值求解效率低的问题,构建了综合考虑刀具几何参数、砂轮廓形及磨削运动关系... 圆柱立铣刀螺旋槽的精密磨削是其制造过程中的关键环节,精确建立磨削接触线模型对提升刀具加工质量与效率具有重要意义。文章针对现有接触线方程通用性不足与数值求解效率低的问题,构建了综合考虑刀具几何参数、砂轮廓形及磨削运动关系的通用接触线数学模型,并提出一种基于多区间二分法的高效数值求解策略。该方法能够稳定求取接触线方程的全部解,有效避免漏根与奇异解问题,且通过多组不同规格刀具的实例验证表明,所建模型能准确表征磨削接触关系,数值算法在计算效率与精度上综合优于传统方法,为高精度刀具数控磨削提供了可靠的理论基础与工艺支持。 展开更多
关键词 圆柱立铣刀 螺旋槽磨削 接触线方程 数值解法 几何分析
在线阅读 下载PDF
轨道列车节能运行研究综述
13
作者 连惠 田志强 +2 位作者 宋琦 靳欣妮 王付霞 《铁道运输与经济》 北大核心 2026年第1期27-45,共19页
轨道列车节能运行是实现交通领域绿色低碳发展的关键举措,对降低运营成本、减少环境污染具有重要意义。研究系统综述了轨道列车节能运行的研究进展,从牵引控制策略、再生制动技术、综合优化策略及智能求解算法4个维度展开分析。研究表明... 轨道列车节能运行是实现交通领域绿色低碳发展的关键举措,对降低运营成本、减少环境污染具有重要意义。研究系统综述了轨道列车节能运行的研究进展,从牵引控制策略、再生制动技术、综合优化策略及智能求解算法4个维度展开分析。研究表明,牵引控制策略通过优化速度曲线和工况转换点实现能耗最小化;再生制动技术通过逆变回馈和储能设备提升能量回收效率;综合优化策略兼顾能耗、准点率和乘客舒适性等多目标平衡;智能求解算法为复杂优化问题提供了高效解决方案。然而,现有研究仍面临动态环境适应性不足、多列车协同优化复杂度高、实时性要求严格等挑战。未来研究应进一步融合人工智能与大数据技术,探索更高效的全局优化方法,推动轨道列车节能运行向智能化、精细化方向发展。 展开更多
关键词 轨道交通列车 节能运行 牵引控制 再生能量 综合优化 求解方法
在线阅读 下载PDF
西安地铁网络节点重要性评估
14
作者 张晨 梁亦辰 +1 位作者 彭朋 陈晓轩 《铁道标准设计》 北大核心 2026年第1期9-16,共8页
科学合理地进行城市轨道交通网络节点重要性评估对优化线路布局与节点设计、保障系统安全运营具有重要意义。本研究基于复杂网络理论,运用Space-L网络建模方法构建西安地铁客流加权网络模型,考虑站点的局部与全局重要性、断面客流的分... 科学合理地进行城市轨道交通网络节点重要性评估对优化线路布局与节点设计、保障系统安全运营具有重要意义。本研究基于复杂网络理论,运用Space-L网络建模方法构建西安地铁客流加权网络模型,考虑站点的局部与全局重要性、断面客流的分布差、站点影响域内的人口数及土地利用强度,提出节点区位重要性测度,并结合节点中心性、可靠性与换乘便捷程度制定节点重要性综合指标评价体系,通过改进的优劣解距离(TOPSIS)算法,更加全面地评估西安地铁网络节点重要性,并分析关键节点失效对网络整体的影响。研究表明:重要站点不仅是数量的增加,周围站点重要性也在随之提升,进一步说明本节点重要性对相邻节点具有一定的贡献率;重要性值大于0.62的站点碎片聚集衔接,其方向与城市的发展相互促进,相辅相成;西安市轨道交通网络的早高峰空间演化规律重点有向东北方向发展趋势;本文模型所识别出的重要节点能很好地体现节点在网络中的功能特性,不同攻击策略下按选择性(S_(i))大小顺序对网络进行破坏时,网络以最快速度崩溃直至网络效率降低到0.2,与随机失效相比,西安地铁复杂网络的抗毁性更加脆弱。 展开更多
关键词 地铁网络 复杂网络 节点重要性 优劣解距离法 网络效率 拓扑结构
在线阅读 下载PDF
分段混合决策规则下多阶段混合整数鲁棒优化调度方法
15
作者 韦子瑜 王磊 +3 位作者 索璕 苏宁赛 赵质淼 薛世伟 《中国电机工程学报》 北大核心 2026年第4期1443-1457,I0012,共16页
考虑调度非预期性(dispatch non-anticipativity,DN)的多阶段优化调度建模方法研究是破解规模化新能源并网背景下日前/日内调度模式运行风险桎梏、保障系统可靠运行与新能源消纳的关键手段。首先,拓展电力系统DN建模方法,构建了分段混... 考虑调度非预期性(dispatch non-anticipativity,DN)的多阶段优化调度建模方法研究是破解规模化新能源并网背景下日前/日内调度模式运行风险桎梏、保障系统可靠运行与新能源消纳的关键手段。首先,拓展电力系统DN建模方法,构建了分段混合决策规则(piecewise mixed decision rules,PMDR)下多阶段鲁棒混合整数鲁棒优化调度模型;然后,分析PMDR结构,结合所提关键约束情景(critically binding scenarios,CBSs)先验求取定理与高维凸包等效建模方法,提出了热启动过程、线性强对偶定理、改进割平面法相结合的高效求解方法;最后,依托改进的IEEE 39节点系统,验证了所提调度模型、求解方法及CBSs求取定理的有效性,并归纳说明了该建模方法的应用范畴。 展开更多
关键词 调度非预期性 可靠运行 多阶段混合整数鲁棒 分段混合决策规则 高效求解方法
原文传递
大语言模型驱动的室内场景布局算法
16
作者 宋佩华 辛国钰 成晶晶 《南宁师范大学学报(自然科学版)》 2026年第2期90-98,共9页
室内场景布局是影响居住空间美观性和功能性的重要因素。针对传统室内场景布局方法融合用户个性化需求、生成符合用户期望的布局方案效率低下的问题,本文提出一种大语言模型驱动的室内场景布局算法。该算法利用大语言模型的自然语言理... 室内场景布局是影响居住空间美观性和功能性的重要因素。针对传统室内场景布局方法融合用户个性化需求、生成符合用户期望的布局方案效率低下的问题,本文提出一种大语言模型驱动的室内场景布局算法。该算法利用大语言模型的自然语言理解和空间推理能力,解析基于自然语言描述的用户布局需求,确定主要家具的位置,实现室内场景基本布局结构;同时,采用遗传算法对其他家具进行全局优化布局,综合考虑重叠约束、距离约束等多重约束条件,实现用户语义需求与自动布局的协同一致。实验结果表明,本文算法能够有效融合用户的个性化布局需求,利用大语言模型将用户的家具摆放需求(通过自然语言描述)进行解析,转化为室内场景布局位置,实现从用户语义到布局位置的映射,并通过遗传算法进行布局优化,统一处理重叠、距离等关键约束,生成合理的室内场景布局。实验结果验证了该算法在布局合理和求解效率等方面的有效性。 展开更多
关键词 大语言模型 室内场景 布局算法 遗传算法 语义理解 求解效率
在线阅读 下载PDF
Revolutionizing Passive Radiative Cooling Materials:Biomass‑Based Photoluminescent Aerogels Opens New Frontiers for Sustainable Energy Efficiency Cooling Solutions
17
作者 Zhiyu Huang Fengxiang Chen Weilin Xu 《Advanced Fiber Materials》 2025年第4期977-980,共4页
With the increasing global energy consumption and cooling demands,traditional active cooling technologies face inefficiency and environmental challenges.Recently published in Science,a team led by Prof.Hai-bo Zhao has... With the increasing global energy consumption and cooling demands,traditional active cooling technologies face inefficiency and environmental challenges.Recently published in Science,a team led by Prof.Hai-bo Zhao has proposed and developed a biomass-based photoluminescent aerogel made from DNA and gelatin to address these challenges.This material achieves a solar-weighted reflectance of over 100%(0.4-0.8μm)and provides a cooling effect of 16.0℃under sunlight.This sustainable material is repairable,recyclable,and biodegradable,offering significant potential for energy-efficient buildings and wearable cooling devices. 展开更多
关键词 biomass based active cooling technologies passive radiative cooling cooling solutions energy efficiency dna gelatin sustainable material thermal management
原文传递
Pareto Efficient Solution and the Class of α-Major Efficient Solutions 被引量:1
18
作者 胡毓达 《Chinese Science Bulletin》 SCIE EI CAS 1994年第10期793-796,共4页
As we know, the Pareto efficient (optimal) solution or in other words, thenoninferior solution, is a basic concept in multiobjective programming. In thesense of this kind of solution, much theoretical and application ... As we know, the Pareto efficient (optimal) solution or in other words, thenoninferior solution, is a basic concept in multiobjective programming. In thesense of this kind of solution, much theoretical and application work has been doneon solutions in multiobjective programming since the 1950s. However, because thePareto efficient solution is only a solution with respect to a vector objective beingnoinnferior, as for a given multiobjective programming problem, its set is large whenthe number of objectives is great. This is an inevitable flaw caused by definingPareto efficient solution with the partial order induced by a positive cone. Yu intro-duced the nondominated solution on the basis of a general convex cone or 展开更多
关键词 MULTIOBJECTIVE PROGRAMMING PARETO efficient solution α-major efficient solution.
在线阅读 下载PDF
Chromium-ruthenium oxide solid solution electrocatalyst for highly efficient oxygen evolution reaction in acidic media 被引量:9
19
《Science Foundation in China》 CAS 2019年第1期29-29,共1页
With the support of the National Natural Science Foundation of China and the aided program for Science and Technology Innovative Research Team of Ningbo Municipality,the research team led by Prof.ChenLiang(陈亮)at Nin... With the support of the National Natural Science Foundation of China and the aided program for Science and Technology Innovative Research Team of Ningbo Municipality,the research team led by Prof.ChenLiang(陈亮)at Ningbo Institute of Materials Technology and Engineering,Chinese Academy of Sciences,reported a chromium-ruthenium oxide solid solution electrocatalyst for the highly efficient oxygen evolution reaction(OER)in acidic media. 展开更多
关键词 Chromium-ruthenium OXIDE solid solution ELECTROCATALYST highly efficient oxygen evolution reaction ACIDIC media
原文传递
Benson proper efficiency for vector optimization of generalized subconvexlike set-valued maps in ordered linear spaces 被引量:2
20
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
在线阅读 下载PDF
上一页 1 2 69 下一页 到第
使用帮助 返回顶部