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11.

This paper presents a machine-learning approach using a multi-layered neural network (NN) with application to a sintering process in an iron- and steel-making plant. Our method induces 'operational rules' that determine operational conditions to obtain products that meet a given quality specification. In our application, an operational condition decides the appropriate ranges of chemical composition and heat input to obtain sinter with desirable properties. Our approach consists of two stages. First, backpropagation (BP) training is performed to obtain a NN which decides whether a given condition is appropriate or not. Secondly, from the trained NN, we extract rules which explain what operational conditions are appropriate. In spite of the effective learning capability, a major drawback of a NN is 'unreadability' of the learned knowledge, or the lack of an explanatory capability, which is crucial in the second stage. We developed a rule extraction algorithm which contributes to overcoming this 'unreadability'. The extracted rules are found to agree well with the knowledge in material science.  相似文献   
12.
Increasing access, even increasing supply, may not be sufficient to attract young teens who do not typically participate in youth programs. Several youth mapping projects in rural and urban communities have led to these conclusions: youth do not know what is available even in their own neighborhoods, young teens have a strong voice in how they spend their discretionary time, and we need to learn how to market youth programs much more effectively. This author reviews important findings from youth community-mapping experiences and showcases a project attempting to move beyond access and supply issues to increasing young people's interest and engagement in community youth development programs.  相似文献   
13.
Medicine and epidemiology currently dominate the study of the strong association between socioeconomic status and mortality. Socioeconomic status typically is viewed as a causally irrelevant "confounding variable" or as a less critical variable marking only the beginning of a causal chain in which intervening risk factors are given prominence. Yet the association between socioeconomic status and mortality has persisted despite radical changes in the diseases and risk factors that are presumed to explain it. This suggests that the effect of socioeconomic status on mortality essentially cannot be understood by reductive explanations that focus on current mechanisms. Accordingly, Link and Phelan (1995) proposed that socioeconomic status is a "fundamental cause" of mortality disparities-that socioeconomic disparities endure despite changing mechanisms because socioeconomic status embodies an array of resources, such as money, knowledge, prestige, power, and beneficial social connections, that protect health no matter what mechanisms are relevant at any given time. We identified a situation in which resources should be less helpful in prolonging life, and derived the following prediction from the theory: For less preventable causes of death (for which we know little about prevention or treatment), socioeconomic status will be less strongly associated with mortality than for more preventable causes. We tested this hypothesis with the National Longitudinal Mortality Study, which followed Current Population Survey respondents (N = 370,930) for mortality for nine years. Our hypothesis was supported, lending support to the theory of fundamental causes and more generally to the importance of a sociological approach to the study of socioeconomic disparities in mortality.  相似文献   
14.
Most infants with more than 6 weeks of crawling experience completely avoid the deep side of a visual cliff ( Campos, Bertenthal, & Kermoian, 1992 ; Gibson & Walk, 1960 ). However, some experienced crawlers do move onto the transparent surface suspended several feet above the ground. An important question is whether these nonavoiders lack wariness of heights or whether they have a qualitatively different way of showing their wariness than do avoiders of the deep side. The current study addressed this question by measuring heart rate (HR) acceleration upon being lowered on the deep and shallow sides of the visual cliff, latency to crawl toward the mother, and tactile exploration of the cliff surface. Nonavoiders and avoiders had indistinguishable patterns of HR acceleration, showing greater HR acceleration when lowered onto the deep than when lowered onto the shallow side of the cliff. Nonavoiders also showed more tactile exploration and longer latencies than did a comparable group of infants tested on the shallow side. This study illustrates how the same emotion, wariness of heights, can be shown by qualitatively different behaviors, all serving the same function of protecting the individual from falling over a drop‐off.  相似文献   
15.
Residents of towns and villages in Arctic Alaska live on “the front line of climate change.” Some communities face immediate threats from erosion and flooding associated with thawing permafrost, increasing river flows, and reduced sea ice protection of shorelines. The term climigration, referring to migration caused by climate change, originally was coined for these places. Although initial applications emphasized the need for government relocation policies, it has elsewhere been applied more broadly to encompass unplanned migration as well. Some historical movements have been attributed to climate change, but closer study tends to find multiple causes, making it difficult to quantify the climate contribution. Clearer attribution might come from comparisons of migration rates among places that are similar in most respects, apart from known climatic impacts. We apply this approach using annual 1990–2014 time series on 43 Arctic Alaska towns and villages. Within-community time plots show no indication of enhanced out-migration from the most at-risk communities. More formally, there is no significant difference between net migration rates of at-risk and other places, testing several alternative classifications. Although climigration is not detectable to date, growing risks make either planned or unplanned movements unavoidable in the near future.  相似文献   
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17.
Abstract: In many democratic societies, including Japan, political alienation such as political cynicism or inefficacy is widespread among the general public. Some researchers argue that along with various other factors embedded in political systems, the mass media, particularly television, plays a crucial role in promoting or intensifying political alienation. Focusing on the influence of the media, this study examines whether television news induces political cynicism and inefficacy in Japan. Previous research has indicated that public and commercial broadcasts may have different impacts on the political attitude of the audience. Thus, this study predicts that the relationship between television news exposure and political alienation would be stronger among those who exclusively watch commercial news programs. The results of hierarchical multiple regression analyses indicate that among non-Nippon Hoso Kyokai (NHK) news viewers, those who view television news more frequently are more likely to feel politically inefficacious, and that those who rely exclusively on television for political information are more likely to be politically cynical. However, negative influences associated with television reliance or television news viewing are not observed among the NHK news viewers, although positive influences are also not observed. Thus, according to the results, the "videomalaise" effect would be limited to certain viewers. This article discusses the implications of the findings and also suggests that more exclusive psychological explanations be examined for the videomalaise effect.  相似文献   
18.
Although a macro‐organizational perspective has become increasingly commonplace in social movement analyses, few studies examine the full spectrum of organizations in any single social movement industry (SMI). Utilizing a unique source of data on Japanese environmental movement organizations, we compare characteristics of groups focused primarily on environmental issues with those for whom environmental issues are part of a larger multi‐issue focus. We then profile across distinct, and theoretically important, organizational domains to assess how local, prefectural and national groups compare on a variety of organizational attributes, including: size, membership type, tactics and activities, and issues. We conclude by discussing the implications of our findings for understanding both Japanese environmentalism and the structure of SMIs generally.  相似文献   
19.
Historical demography as a separate discipline came into existence when family reconstruction was first developed for the analysis of a pre-transition population. This paper assesses the significant achievements made in this field of population studies since then. Attention is also paid to equally significant findings obtained from aggregative analysis based on back projection, and to a large body of research results for the period of the demographic transition. In the last part of the paper, new research directions are discussed. Data issues as well as methodological ones are raised. Special attention is given to newly emerging Asian historical demography where different source materials require different methods and techniques, which in turn are expected to broaden the scope of the so far disproportionality fertility-oriented field. Finally, discussions are extended to economic, cultural and institutional aspects of the subject, with a plea not to isolate demographic analysis from other branches of historical research.  相似文献   
20.
本文介绍的联用分析系统是将超临界流体萃取(SFE)系统与超高效液相色谱(UHPLC)系统联用。使用在线SFE-UHPLC系统,可以完成对胡椒粉中胡椒碱成分的高速萃取和分析。整个分析过程包括萃取时间在内只需要7min。将此方法的萃取回收率与其他萃取方法进行比较,SFE方法得到的回收率与其他方法相当。这种在线SFE-UHPLC方法操作简单,分析速度快。这一方法对于分析固体样品中的化合物组分非常有用,可以有效避免繁琐的样品预处理过程。  相似文献   
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