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论海明威作品中的“硬汉”形象(英文)
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作者 杨大亮 《上海电力学院学报》 CAS 2001年第2期63-68,共6页
论述了美国伟大作家海明威塑造的“硬汉”形象这一主题 ,分析了“硬汉”形象的主要特征 ,表现在以下几个方面 :(1)海明威作品中存在着一个重复出现的人物 ,而这一人物与海明威本人存在着极其密切的关系 ;(2 )人物对生活的认识仅限于他... 论述了美国伟大作家海明威塑造的“硬汉”形象这一主题 ,分析了“硬汉”形象的主要特征 ,表现在以下几个方面 :(1)海明威作品中存在着一个重复出现的人物 ,而这一人物与海明威本人存在着极其密切的关系 ;(2 )人物对生活的认识仅限于他早年对战争和暴力的经历 ;(3)在“硬汉式”英雄身上存在着一套价值模式 ,而这一价值模式正是主人公所竭力获得的 ;(4 )海明威早期作品中的人物缺乏这一套价值模式 ,是被动的和被打败的 ,在后期作品中 ,人物获得了这一套价值模式 ,是积极的 ,未被打败的 。 展开更多
关键词 价值模式 海明威作品 "硬汉"形象 人物
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高空长悬挑桁架施工变形预调控制技术
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作者 王峰 侯彦果 +4 位作者 郑文锦 闻陈宝 孟凡光 邓莉兰 王刚 《工业建筑》 2024年第11期220-225,共6页
大型复杂钢结构成型态(形态与力态)一直是施工重点关注的问题。复杂结构施工成型态通常与设计态存在偏差,为了保证形态和力态满足设计和安全要求,需要对结构施工过程形态与力态进行分析与控制。基于深圳自贸中心项目长悬挑桁架,考虑了... 大型复杂钢结构成型态(形态与力态)一直是施工重点关注的问题。复杂结构施工成型态通常与设计态存在偏差,为了保证形态和力态满足设计和安全要求,需要对结构施工过程形态与力态进行分析与控制。基于深圳自贸中心项目长悬挑桁架,考虑了结构分步施工加载、楼板混凝土浇筑的液态荷载渐变硬化等因素的影响,重点研究了变形预调值的计算与收敛性,分析了经过变形预调后结构位移和应力状态,评估了施工过程的安全性并提出合理的施工建议。结果表明:不同楼层混凝土浇筑刚度形成过程对变形预调值计算与应力变化的影响不可忽略;悬挑桁架结构预调值正装迭代计算收敛性明显,一次迭代可满足计算精度要求;混凝土楼板端部若与主体结构直接浇筑在一起,其边界约束较强,会在后续加载过程中造成其应力超限,可通过设置后浇带释放应力。 展开更多
关键词 分步施工 悬挑桁架 变形预调值 正装迭代
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集值映射的极小极大定理 被引量:1
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作者 胡金海 李声杰 《经济数学》 2008年第3期325-330,共6页
本文利用一类非线性标量化函数的性质证明了关于集值映射的极小极大定理,并给出具体例子验证了定理的结论.
关键词 非线性标量化函数 极小极大定理 集值映射
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一种基于密度的Web文本聚类算法 被引量:1
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作者 许芳芳 《电脑知识与技术(过刊)》 2015年第3X期234-235 239,239,共3页
针对DBSCAN算法采用全局参数Eps、对高维数据处理能力不足等问题,提出一种改进算法,该算法结合蚁群聚类算法实现数据集的划分以获取参数Eps的值组,然后根据不同的Eps值分别调用DBSCAN算法,从而实现对Web文本的聚类。实验结果表明,改进... 针对DBSCAN算法采用全局参数Eps、对高维数据处理能力不足等问题,提出一种改进算法,该算法结合蚁群聚类算法实现数据集的划分以获取参数Eps的值组,然后根据不同的Eps值分别调用DBSCAN算法,从而实现对Web文本的聚类。实验结果表明,改进后的算法的有效性有所提高。 展开更多
关键词 WEB文本 DBSCAN 蚁群聚类 Eps值组
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双定压值定压方法应用研究
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作者 张恒 《建筑热能通风空调》 2001年第5期20-22,共3页
提出的双定压值定压方法 ,可使供暖系统降压运行 ,以满足特殊地形及旧有建筑承压之需要。采用本方法定压 ,定压点压力不再是一个始终不变的值 ,而是根据系统静止或运行状态可相应改变的两个不同的压力值。
关键词 定压点 恒压点 双定压值 供热 采暖
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践行十九大精神 加强新时代高校师德建设
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作者 高军青 《珠江论丛》 2018年第2期110-116,共7页
习近平同志所做的党的十九大报告再一次强调“全面贯彻党的教育方针,落实立德树人根本任务”。为推进高等教育事业取得新的进步,必须进一步加强和改进高校师德建设,具体应从用十九大精神灌溉师德土壤、培育风清气正的师德土壤、用党的... 习近平同志所做的党的十九大报告再一次强调“全面贯彻党的教育方针,落实立德树人根本任务”。为推进高等教育事业取得新的进步,必须进一步加强和改进高校师德建设,具体应从用十九大精神灌溉师德土壤、培育风清气正的师德土壤、用党的先进性优化师德土壤、扎根第一线的师德实践土壤四个方面着手进行。 展开更多
关键词 教育强国 教师伦理 师德 立德树人
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Transitivity, mixing and chaos for a class of set-valued mappings 被引量:9
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作者 LIAO Gongfu, WANG Lidong & ZHANG Yucheng Institute of Mathematics, Jilin University, Changchun 130012, China Institute of Nonlinear Information Technology, Dalian Nations University, Dalian 116600, China Department of Mathematics, University of Science and Technology of China, Hefei 230026, China 《Science China Mathematics》 SCIE 2006年第1期1-8,共8页
Consider the continuous map f : x → X and the continuous map f of K,(X) into itself induced by f, where X is a metric space and K(X) the space of all non-empty compact subsets of x endowed with the Hausdorff metric. ... Consider the continuous map f : x → X and the continuous map f of K,(X) into itself induced by f, where X is a metric space and K(X) the space of all non-empty compact subsets of x endowed with the Hausdorff metric. According to the questions whether the chaoticity of f implies the chaoticity of f posed by Roman-Flores and when the chaoticity of f implies the chaoticity of f posed by Fedeli, we investigate the relations between f and f in the related dynamical properties such as transitivity, weakly mixing and mixing, etc. And by using the obtained results, we give the satisfied answers to Roman-Flores's question and Fedeli's question. 展开更多
关键词 set-valuED mapping transitivity WEAK mixing mixing chaos.
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CONE-DIRECTED CONTINGENT DERIVATIVES AND GENERALIZED PREINVEX SET-VALUED OPTIMIZATION 被引量:10
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作者 丘京辉 《Acta Mathematica Scientia》 SCIE CSCD 2007年第1期211-218,共8页
By using cone-directed contingent derivatives, the unified necessary and sufficient optimality conditions are given for weakly and strongly minimal elements respectively in generalized preinvex set-valued optimization.
关键词 Preinvex set-valued optimization cone-directed contingent derivative optimality conditions
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Globally Proper Saddle Point in Ic-Cone-Convexlike Set-Valued Optimization Problems 被引量:9
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作者 Guo Lin YU San Yang LIU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2009年第11期1921-1928,共8页
The existence conditions of globally proper efficient points and a useful property of ic- cone-convexlike set-valued maps are obtained. Under the assumption of the ic-cone-convexlikeness, the optimality conditions for... The existence conditions of globally proper efficient points and a useful property of ic- cone-convexlike set-valued maps are obtained. Under the assumption of the ic-cone-convexlikeness, the optimality conditions for globally proper efficient solutions are established in terms of Lagrange multipliers. The new concept of globally proper saddle-point for an appropriate set-valued Lagrange map is introduced and used to characterize the globally proper efficient solutions. The results which are obtained in this paper are proven under the conditions that the ordering cone need not to have a nonempty interior. 展开更多
关键词 set-valued map IC-CONE-CONVEXLIKENESS globally proper efficiency saddle point
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Radar Target Recognition Algorithm Based on RCS Observation Sequence——Set-Valued Identification Method 被引量:10
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作者 WANG Ting BI Wenjian +1 位作者 ZHAO Yanlong XUE Wenchao 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2016年第3期573-588,共16页
This paper studies the problem of radar target recognition based on radar cross section(RCS)observation sequence.First,the authors compute the discrete wavelet transform of RCS observation sequence and extract a valid... This paper studies the problem of radar target recognition based on radar cross section(RCS)observation sequence.First,the authors compute the discrete wavelet transform of RCS observation sequence and extract a valid statistical feature vector containing five components.These five components represent five different features of the radar target.Second,the authors establish a set-valued model to represent the relation between the feature vector and the authenticity of the radar target.By set-valued identification method,the authors can estimate the system parameter,based on which the recognition criteria is given.In order to illustrate the efficiency of the proposed recognition method,extensive simulations are given finally assuming that the true target is a cone frustum and the RCS of the false target is normally distributed.The results show that the set-valued identification method has a higher recognition rate than the traditional fuzzy classification method and evidential reasoning method. 展开更多
关键词 Feature extraction radar target recognition RCS set-valued identification wavelet transform.
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Henig Efficiency in Vector Optimization with Nearly Cone-subconvexlike Set-valued Functions 被引量:8
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作者 Qiu-sheng Qiu 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2007年第2期319-328,共10页
In this paper, we study Henig efficiency in vector optimization with nearly cone-subconvexlike set-valued function. The existence of Henig efficient point is proved and characterization of Henig efficiency is establis... In this paper, we study Henig efficiency in vector optimization with nearly cone-subconvexlike set-valued function. The existence of Henig efficient point is proved and characterization of Henig efficiency is established using the method of Lagrangian multiplier. As an interesting application of the results in this paper, we establish a Lagrange multiplier theorem for super efficiency in vector optimization with nearly conesubconvexlike set-valued function. 展开更多
关键词 set-valued function vector optimization Lagrangian multiplier theorem Henig efficiency nearly cone-subconvexlikeness
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Common Fixed Point Theorems for Sequences of φ-type Contraction Set-valued Mappings 被引量:9
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作者 WU Jian-rong LIU Hai-yan 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第4期504-510,共7页
In complete metric spaces, the common fixed point theorems for sequences of φ-type contraction set-valued mappings are established, and the corresponding random com- mon fixed point theorems for set-valued mappings a... In complete metric spaces, the common fixed point theorems for sequences of φ-type contraction set-valued mappings are established, and the corresponding random com- mon fixed point theorems for set-valued mappings are also obtained. 展开更多
关键词 sequence of set-valued mappings common fixed point random fixed point metric space
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基于属性集值不完备信息系统的Rough集方法 被引量:7
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作者 叶小平 吉永杰 《计算机工程与应用》 CSCD 北大核心 2005年第3期178-180,232,共4页
论文使用基于一般关系的Rough集理论和方法,研究了具有“属性集值”的不完备信息系统。通过研究由属性集值产生的不完备信息系统上的三种基本关系相容关系、非对称相似关系和拟序关系,建立了相应Rough近似集合的某种“单调”关系。在此... 论文使用基于一般关系的Rough集理论和方法,研究了具有“属性集值”的不完备信息系统。通过研究由属性集值产生的不完备信息系统上的三种基本关系相容关系、非对称相似关系和拟序关系,建立了相应Rough近似集合的某种“单调”关系。在此基础上,讨论了系统属性约简及其实现算法。 展开更多
关键词 属性集值 不完备信息系统 ROUGH集方法 属性约简
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HENIG GLOBALLY EFFICIENCY FOR SET-VALUED OPTIMIZATION AND VECTOR VARIATIONAL INEQUALITY 被引量:6
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作者 YU Guolin 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2014年第2期338-349,共12页
This paper deals with Henig globally efficiency in vector optimization involving generalized cone-preinvex set-valued mapping. Some properties of generalized cone-preinvex set-valued map are derived. It also disclose ... This paper deals with Henig globally efficiency in vector optimization involving generalized cone-preinvex set-valued mapping. Some properties of generalized cone-preinvex set-valued map are derived. It also disclose the closed relationships between Henig globally efficiency of generalized conepreinvex set-valued optimization problem and Henig globally efficiency of a kind of vector variational inequality. 展开更多
关键词 Contingent epiderivative generalized cone-preinvex set-valued mapping Henig globallyefficiency set-valued optimization vector variational inequality.
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TOPOLOGICAL STRUCTURE OF EFFICIENT SET OF OPTIMIZATION PROBLEM OF SET-VALUED MAPPING 被引量:7
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作者 LI YUANXI 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 1994年第1期115-122,共8页
This paper is concerned with the topological structure of efficient sets for optimizationproblem of set-valued mapping. It is proved that these sets are closed or. connected under someconditions on cone-continuity, co... This paper is concerned with the topological structure of efficient sets for optimizationproblem of set-valued mapping. It is proved that these sets are closed or. connected under someconditions on cone-continuity, cone-convexity and cone-quasiconvexity. 展开更多
关键词 Optimization of set-valued mapping Vector optimization Efficient solution Cone-convexity Cone-quasiconvexity Closedness Connectedness.
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THE OPTIMALITY CONDITIONS OF NONCONVEXSET-VALUED VECTOR OPTIMIZATION 被引量:2
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作者 盛保怀 刘三阳 《Acta Mathematica Scientia》 SCIE CSCD 2002年第1期47-55,共9页
The concepts of alpha-order Clarke's derivative, alpha-order Adjacent derivative and alpha-order G.Bouligand derivative of set-valued mappings are introduced, their properties are studied, with which the Fritz Joh... The concepts of alpha-order Clarke's derivative, alpha-order Adjacent derivative and alpha-order G.Bouligand derivative of set-valued mappings are introduced, their properties are studied, with which the Fritz John optimality condition of set-valued vector optimization is established. Finally, under the assumption of pseudoconvexity, the optimality condition is proved to be sufficient. 展开更多
关键词 set-valued derivative optimality condition pseudoconvex set-valued mapping
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Continuous Selection,Collectively Fixed Points and System of Coincidence Theorems in Product Topological Spaces 被引量:4
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作者 Xie Ping DING 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2006年第6期1629-1638,共10页
Some new continuous selection theorems are first proved in noncompact topological spaces. As applications, some new collectively fixed point theorems and coincidence theorems for two families of set-valued mappings de... Some new continuous selection theorems are first proved in noncompact topological spaces. As applications, some new collectively fixed point theorems and coincidence theorems for two families of set-valued mappings defined on product space of noncompact topological spaces are obtained under very weak assumptions. These results generalize many known results in recent literature. 展开更多
关键词 continuous selection collectively fixed point coincidence theorem for two families of set-valued mappings FC-SPACE
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On Ha's Version of Set-valued Ekeland's Variational Principle 被引量:4
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作者 Jing Hui QIU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2012年第4期717-726,共10页
By using the concept of cone extensions and Dancs-Hegedus-Medvegyev theorem, Ha [Some variants of the Ekeland variational principle for a set-valued map. J. Optim. Theory Appl., 124, 187-206 (2005)] established a ne... By using the concept of cone extensions and Dancs-Hegedus-Medvegyev theorem, Ha [Some variants of the Ekeland variational principle for a set-valued map. J. Optim. Theory Appl., 124, 187-206 (2005)] established a new version of Ekeland's variational principle for set-valued maps, which is expressed by the existence of strict approximate minimizer for a set-valued optimization problem. In this paper, we give an improvement of Ha's version of set-valued Ekeland's variational principle. Our proof is direct and it need not use Dancs-Hegedus-Medvegyev theorem. From the improved Ha's version, we deduce a Caristi-Kirk's fixed point theorem and a Takahashi's nonconvex minimization theorem for set-valued maps. Moreover, we prove that the above three theorems are equivalent to each other. 展开更多
关键词 Ekeland's variational principle set-valued map locally convex space Caristi-Kirk's fixedpoint theorem Takahashi's nonconvex minimization theorem
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NONEMPTY INTERSECTION THEOREMS AND SYSTEM OF GENERALIZED VECTOR EQUILIBRIUM PROBLEMS IN PRODUCT G-CONVEX SPACES 被引量:4
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作者 DINGXie-ping 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第6期618-626,共9页
By using an existence theorems of maximal elements for a family of set-valued mappings in G-convex spaces due to the author, some new nonempty intersection theorems for a family of set-valued mappings were established... By using an existence theorems of maximal elements for a family of set-valued mappings in G-convex spaces due to the author, some new nonempty intersection theorems for a family of set-valued mappings were established in noncompact product G-convex spaces. As applications, some equilibrium existence theorems for a system of generalized vector equilibrium problems were proved in noncompact product G-convex spaces. These theorems unify, improve and generalize some important known results in literature. 展开更多
关键词 family of set-valued mapping nonempty intersection theorem system of generalized vector equilibrium problem product G-convex space
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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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