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101.
We present two experiments investigating the role of emotions concerning technological and natural hazards. In the first experiment, technological hazards aroused stronger emotions, and were considered to be riskier than natural hazards. No differences were found between the texts versus audio presentations. However, the presence of pictures aroused stronger emotions and increased the perceived risk. Emotions play a mediating role between hazard types and perceived risk, as well as between pictures and perceived risk. The second experiment adopted real‐world materials from webpages and TV. Emotions again play a mediating role between pictorial information and risk perception. Moreover, specific emotions were found to be associated with different types of action tendencies. For example, loss‐based emotions (e.g., fear, regret) tend to lead to prevention strategies, whereas ethical emotions (e.g., anger) lead to aggressive behavior. We also find that loss‐based emotions in the technical hazard scenario trigger more coping strategies (from prevention to retaliation) than in the natural hazard scenario. 相似文献
102.
顾士敏 《云南民族大学学报(哲学社会科学版)》2000,17(5):71-75
《红楼梦》以一群“正邪两赋”的“人格”形象及其各种各样爱情的足迹,展现出一幅如诗如画的“玉堂金马红楼梦”中的生活画卷,从而以“滑稽”与“庄严”同在的宗教意识作为这一“生活”的“衰草枯杨好了歌”。“假语村言”敷衍出的一段故事,概括起的却是一部真实的文化史和一次审美意义上的文化批判,具有一种“文化结论”的意义,从而成为中国文化的一个“寓言”。 相似文献
103.
Zonghao Gu George L. Nemhauser Martin W.P. Savelsbergh 《Journal of Combinatorial Optimization》2000,4(1):109-129
We investigate lifting, i.e., the process of taking a valid inequality for a polyhedron and extending it to a valid inequality in a higher dimensional space. Lifting is usually applied sequentially, that is, variables in a set are lifted one after the other. This may be computationally unattractive since it involves the solution of an optimization problem to compute a lifting coefficient for each variable. To relieve this computational burden, we study sequence independent lifting, which only involves the solution of one optimization problem. We show that if a certain lifting function is superadditive, then the lifting coefficients are independent of the lifting sequence. We introduce the idea of valid superadditive lifting functions to obtain good aproximations to maximum lifting. We apply these results to strengthen Balas' lifting theorem for cover inequalities and to produce lifted flow cover inequalities for a single node flow problem. 相似文献
104.
本文提出了用干涉及滤波技术实现图象边缘增强的一种新方法。将同一物体的一张正确对焦的透明片与另一张离焦的透明片重叠放在透镜的前面,在单色平行光照射下,在透镜的后焦面上得到两图象的谱的干涉,通过对干涉条纹的适当滤波,可在输出面得到边缘增强的象。 相似文献
105.
Jean-Claude Guédon 《Serials Review》2008,34(1):41-51
Three years ago, the Gold and Green Roads to Open Access were viewed as complementary strategies, with repositories having the potential of gradually behaving more like journals, and vice versa. Since then, repositories and journals have been progressing on parallel tracks. Re-examining the situation, the reasoning suggested in 2004 appears still valid. Simultaneously, a knowledge economy has made of science a strategic resource. The developing world is essentially invited to contribute to world science with little or no regard to the development of an autonomous scientific capacity. Open Access, in this context, takes a new meaning with one objective to help development of local and autonomous scientific capacity. However, to do so, mixing and matching repositories with journals is needed. Brazil exemplifies this type of development and shows how the Green and Gold roads can mix and match. 相似文献
106.
We propose a new stochastic approximation (SA) algorithm for maximum-likelihood estimation (MLE) in the incomplete-data setting. This algorithm is most useful for problems when the EM algorithm is not possible due to an intractable E-step or M-step. Compared to other algorithm that have been proposed for intractable EM problems, such as the MCEM algorithm of Wei and Tanner (1990), our proposed algorithm appears more generally applicable and efficient. The approach we adopt is inspired by the Robbins-Monro (1951) stochastic approximation procedure, and we show that the proposed algorithm can be used to solve some of the long-standing problems in computing an MLE with incomplete data. We prove that in general O(n) simulation steps are required in computing the MLE with the SA algorithm and O(n log n) simulation steps are required in computing the MLE using the MCEM and/or the MCNR algorithm, where n is the sample size of the observations. Examples include computing the MLE in the nonlinear error-in-variable model and nonlinear regression model with random effects. 相似文献
107.
本文利用洋葱内表皮细胞作为实验材料,观察细胞骨架结构.实验结果显示植物细胞骨架呈网状结构,分布在整个细胞质中;幼嫩细胞的细胞骨架比较密集,吸附较多蛋白质,须经多次洗涤后才可获得较为清晰的图片.进一步的研究表明,与幼嫩细胞的细胞骨架相比,衰老细胞的细胞骨架出现部分解聚的现象;幼嫩细胞的细胞骨架在低温条件下亦出现解聚现象.使用洋葱内表皮观察细胞的骨架结构为我们在简便、经济的条件下,通过普通光学显微镜观察骨架提供了可能.这种方法为今后进一步开展细胞骨架的功能研究奠定了基础. 相似文献
108.
我国区域工业竞争力的测定与评价——我国十大沿海城市工业的广义竞争力实证比较研究 总被引:2,自引:0,他引:2
本文认为竞争力应该不仅仅是从“争”的角度来理解,更应该从“和而不同”的角度来理解,即广义竞争力,“竞合力”或者说广义上的竞争力才是提升工业竞争力的关键所在。正是基于这种广义竞争力的新视角,本文采用了两种不同的竞争力测定方法,对沿海十大城市的工业竞争力进行了实证比较研究。 相似文献
109.
顾元华 《盐城工学院学报(社会科学版)》2007,20(4):27-29
以David Hawkes《葬花辞》译文为例,从静态性与动态性、主观性与客观性、一元性与二元性、修饰关系与述谓关系等角度浅析英语与汉语在词法、句法、篇章结构等方面存在的差异。 相似文献
110.
自然资本投资是目前学界和政界高度重视的一个问题,国内相关研究成果比较匮乏。本刊特意组织的五篇文章或慎重地对"以自然规律为遵循的人类生存发展之道究竟应当包含哪些内容,从法学的角度进行猜测";或力主"生态经济是自然资本经济,其内容就是自然资本投资","自然资本的非资本化主要是因为法律与政策的不当安排造成的,中国现行法律安排已远远落后于自然资本投资的实际需要,法律必须建立自然资本市场制度";或探讨了自然资本投资对可持续发展的环境资源法制建设的启示;或质疑自然资本投资的法律保护属性,认为其制度设计属于民商法和国际法范畴;或对自然资本主义与可持续发展的契合性加以审视,认为将自然视为资本离真正的可持续发展理念差距尚远。希望通过对这些文章的推介,将对自然资本投资问题的研究引向深入。 相似文献