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401.
采用平均特征词频率策略计算特征词权重,用快速n-grims算法对各特征词所处的概念体进行加权,用一种改进的K-means聚类算法进行段落聚类,提出一种基于局部与全局信息的自动文摘算法并给出算法评估.该算法不仅能够自适应获得k值,而且有效防止了初始点的随机选择对聚类结果的影响.评测结果表明该算法对经济类和科技类文章的准确率和召回率都明显高于新闻类和文学类文章,利用机器文摘进行分类的准确率明显高于使用原文本进行分类.该算法所得到的文摘,在各项指标上都优于传统方法生成的文摘. 相似文献
402.
何永成 《温州大学学报(自然科学版)》2006,27(4):109-113
文化教学是语言教育不可或缺的组成部分。一直以来,各国学者从不同的视角出发,相继探索过语言文化教学的内容、模式与方法,但仁者见仁,智者见智。为了更好地理解语言文化教学的实质与过程,有必要对其发展历史、操作策略作一系统评析,并借此重申语言课堂中开展文化教学的重要性,以及拓展语言教师文化素养的必要性。 相似文献
403.
Roald Hoffmann Jean-Paul Malrieu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(31):12690-12710
We begin our tripartite Essay with a triangle of understanding, theory and simulation. Sketching the intimate tie between explanation and teaching, we also point to the emotional impact of understanding. As we trace the development of theory in chemistry, Dirac's characterization of what is known and what is needed for theoretical chemistry comes up, as does the role of prediction, and Thom's phrase “To predict is not to explain.” We give a typology of models, and then describe, no doubt inadequately, machine learning and neural networks. In the second part, we leave philosophy, beginning by describing Roald's being beaten by simulation. This leads us to artificial intelligence (AI), Searle's Chinese room, and Strevens’ account of what a go-playing program knows. Back to our terrain—we ask “Quantum Chemistry, † ca. 2020?” Then move to examples of AI affecting social matters, ranging from trivial to scary. We argue that moral decisions are hardly to be left to a computer. At this point, we try to pull the reader up, giving the opposing view of an optimistic, limitless future a voice. But we don't do justice to that view—how could we? We return to questioning the ascetic dimension of scientists, their romance with black boxes. Onward: In the 3rd part of this Essay, we work our way up from pessimism. We trace (another triangle!) the special interests of experimentalists, who want the theory we love, and reliable numbers as well. We detail in our own science instances where theory gave us real joy. Two more examples-on magnetic coupling in inorganic diradicals, and the way to think about alkali metal halides, show us the way to integrate simulation with theory. Back and forth is how it should be—between painfully-obtained, intriguing numbers, begging for interpretation, in turn requiring new concepts, new models, new theoretically grounded tools of computation. Through such iterations understanding is formed. As our tripartite Essay ends, we outline a future of consilience, with a role both for fact-seekers, and searchers for understanding. Chemistry's streak of creation provides in that conjoined future a passage to art and to perceiving, as we argue we must, the sacred in science. 相似文献
404.
405.
In the age of the Internet and with the dramatic proliferation of mobile listening technologies, music has unprecedented global distribution and embeddedness in people's lives. It is a source of intense experiences of both the most intimate and solitary, and public and collective, kinds – from an individual with their smartphone and headphones, to large-scale live events and global simulcasts; and it increasingly brings together a huge range of cultures and histories, through developments in world music, sampling, the re-issue of historical recordings, and the explosion of informal and home music-making that circulates via YouTube. For many people, involvement with music can be among the most powerful and potentially transforming experiences in their lives. At the same time, there has been increasing interest in music's communicative and affective capacities, and its potential to act as an agent of social bonding and affiliation. This review critically discusses a considerable body of research and scholarship, across disciplines ranging from the neuroscience and psychology of music to cultural musicology and the sociology and anthropology of music, that provides evidence for music's capacity to promote empathy and social/cultural understanding through powerful affective, cognitive and social factors; and explores ways in which to connect and make sense of this disparate evidence (and counter-evidence). It reports the outcome of an empirical study that tests one aspect of those claims, demonstrating that ‘passive’ listening to the music of an unfamiliar culture can significantly change the cultural attitudes of listeners with high dispositional empathy; presents a model that brings together the primary components of the music and empathy research into a single framework; and considers both some of the applications, and some of the shortcomings and problems, of understanding music from the perspective of empathy. 相似文献
406.
Ratchada Viriyapong Monthicha Sookpiam 《Mathematical Methods in the Applied Sciences》2019,42(18):6906-6916
Online game addiction has become a large problem worldwide, and it could give negative impacts on children in many ways such as physical health, learning, emotion, and behavior. Online game addiction is mostly found in children and youth at the age of 15 to 24 years. Therefore, in this paper, we have developed a mathematical model of online game addiction to explore the effects of education campaign and family understanding on online game addiction in Thailand. Analysis of this model reveals two main equilibria, addiction‐free (AFE) and addiction‐present (APE) ones. Results show that the AFE is locally asymptotically stable when the value of basic reproduction number (R0) is less than the unity; otherwise, there is a unique endemic equilibrium point, and it is locally stable when satisfies the Routh‐Hurwitz criterion. Further, the conditions of AFE to be globally stable are demonstrated. Finally, the results of sensitivity analysis and numerical simulation show that the effectiveness of both education campaign and family understanding is an important factor in reducing the value of R0 and holds great promise for lowering the number of children and youth who addict to online game in Thailand. 相似文献
407.
行为检测在自动驾驶、视频监控等领域的广阔应用前景使其成为了视频分析的研究热点。近年来,基于深度学习的方法在行为检测领域取得了巨大的进展,引起了国内外研究者的关注,对这些方法进行了全面的梳理和总结,介绍了行为检测任务的详细定义和面临的主要挑战;从时序行为检测和时空行为检测2个方面对相关文献做了细致地分类,综合分析了每一类别中不同研究方法的思路和优缺点,并阐述了基于弱监督学习、图卷积神经网络、注意力机制等新兴研究话题的相关方法;介绍了行为检测领域常用的数据集以及性能评估指标,在这些数据集上比较了几种典型方法的性能;总结了当前行为检测方法需要解决的问题以及进一步发展的研究方向。 相似文献
408.
自阶级产生以来,人类就从未放弃过对平等理想的追求。马克思平等观通过对抽象平等观和资产阶级平等原则的批判,对近代空想家和启蒙思想各种平等观念的分析,对资本主义经济关系中所谓的平等权利和地位的研究,以及对以往一切平等观念进行历史唯物主义的根本改造,提出了无产阶级的平等观,创造性地把平等理论置于科学的基础之上。对马克思平等观的当代认识,对发展马克思主义有着积极的作用,同时又对建设社会主义和谐社会具有现实的指导意义。 相似文献
409.
Aiming at concrete tasks of information fusion in computer pan-vision(CPV) system,information fusion methods are studied thoroughly,Some research progresses are presented.Recognizing of vision testing object is realized by fusing vision information and non-vision auxiliary information,which contain recognition of material defects,intelligent robot‘s autonomous recognition for parts and computer to defect image understanding and recognition automatically. 相似文献
410.
5至8岁儿童心理理论各成分的发展及其关系 总被引:3,自引:1,他引:3
使用故事-图片法,施测一级错误信念、二级错误信念、解释性心理理论和失言理解4类任务,考察5~8岁儿童多个层次的心理理论能力。结果表明,5岁儿童已经很好地理解一级错误信念。解释性心理理论和二级错误信念理解在类似的年龄发展起来,6~8岁是他们发展的关键时期。8岁儿童还不能很好的理解失言中所包含的认知和情感成分。相关和回归分析的结果表明,一级错误信念理解可能是后来发展的解释性心理理论、二级错误信念理解和失言理解的基础。 相似文献