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41.
ABSTRACT

Moving beyond the dominant bag-of-words approach to sentiment analysis we introduce an alternative procedure based on distributed word embeddings. The strength of word embeddings is the ability to capture similarities in word meaning. We use word embeddings as part of a supervised machine learning procedure which estimates levels of negativity in parliamentary speeches. The procedure’s accuracy is evaluated with crowdcoded training sentences; its external validity through a study of patterns of negativity in Austrian parliamentary speeches. The results show the potential of the word embeddings approach for sentiment analysis in the social sciences.  相似文献   
42.
One striking feature of molecular rotors is their ability to change conformation with detectable optical signals through molecular motion when stimulated. However, due to the strong intermolecular interactions, synthetic molecular rotors have often relied on fluid environments. Here, we take advantage of the solid-state intramolecular motion of aggregation-induced emission (AIE) molecular rotors and one-dimensional fibers, developing highly sensitive optical fiber sensors that respond to ambient humidity rapidly and reversibly with observable chromatic fluorescence change. Moisture environments induce the swelling of the polymer fibers, activating intramolecular motions of AIE molecules to result in red-shifted fluorescence and linear response to ambient humidity. In this case, polymer fiber provides a process-friendly architecture and a physically tunable medium for the embedded AIE molecules to manipulate their fluorescence response characteristics. Assembly of sensor fibers could be built into hierarchical structures, which are adaptive to diverse-configuration for spatial-temporal humidity mapping, and suitable for device integration to build light-emitting sensors as well as touchless positioning interfaces for intelligence systems.  相似文献   
43.
网络环境对图书馆人才的新要求   总被引:35,自引:8,他引:35  
论述了21世纪图书馆在信息网络环境下运行成为必然,并从六个方面概述了网络环境下图书馆人才应具备的素质与知识结构。  相似文献   
44.
本文考察和分析了美国教育走向保守主义的趋势及其所引发的冲突和斗争。美国教育政策的保守趋势运动是多元的,存在着不同的取向,主要有四种力量构成新自由主义、新保守主义、威权民粹主义和正处在上升阶段的由专业人员和管理人员所构成的新中产阶级。本文侧重探讨了保守主义在改造美国教育的运动中居于领导地位的前两支力量,并认为在教育和社会政策领域,这些力量成功地构建成一个联盟,该联盟成功的重要原因在于对常识的改造,作者将之称为“保守主义的现代化”。  相似文献   
45.
The shortage of qualified managers to assign to overseas positions has necessitated rethinking of the viable candidates pools. A relatively new group of global managers have emerged, inpatriate managers. These are foreign nationals and third-country nationals who are relocated to the organization's domestic headquarters to serve as a “linking-pin” to the global marketplace. This paper examines challenges to effectively incorporating these inpatriate managers into the domestic organization. The various issues with inpatriate manager adjustment to the domestic macro and organizational culture are examined. In addition, the necessary social support in work and non-work contexts is discussed.  相似文献   
46.
Linguistic analysis of short published reports leads to the presentation of an aigorithm that depicts the problem-solving process in terms of a series of evaluative questions. The work shows how reports enable us to define in detail the various stages of problem solving, and it shows that an understanding of these various stages enables us to recognise information structures in written texts; the writing of brief reports of high-priority information on which the whole thinking process is based is thus seen as a vital part of the problem-solving process. One report is analysed in detail to demonstrate the close relationship between information structures in the text and the real-life thought'action process it describes. There is discussion of how paragraphs, sentences and signals within the sentences enable the writer to communicate the information in a conceptual array that represents the actual thought/action process it describes. Educational implications for inter-sentential coherence, discourse analysis, and writing structures, and control of research through written reports are all discussed.  相似文献   
47.
Economists and management “scientists” tend to adopt a rationalistic, “black box” approach to the treatment of technological innovation, with decisions to invest in innovation being viewed as climactic acts and with the significant impact of risk and uncertainty often being disregarded. This paper examines an alternative analytical perspective: that a least the early development of technological innovation is a process of incremental decision making where managerial responses are affected by the consequences of previous decisions and by alterations in external information. The development of the “poromeric” Porvair discussed here illustrates the considerable risks that have to be borne when undertaking radical innovation, and the nature of the uncertainties, the interdependency between them and the manner in which they persist, in this case even beyond the commercialization of the new product.  相似文献   
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The study compared general population samples of Jamaican children ages 6–18 years, via Jamaican versions of the Child Behavior Checklist (CBCL) parent-, teacher-, and self-report forms. Repeated measures ANOVAs with informant as a repeated measures factor, assessed base-rate problem score differences according to children’s area of residence (i.e., urban vs rural), gender, and age. No between subjects residence effects emerged for total problem score. However, adolescents self-reported higher total problem scores compared to the ratings they received from their parents and teachers. No gender total problem score effects emerged for any of the three informants, but girls received higher internalizing, and Somatic Complaints scores. Similar total problem scores across genders, and the high ratio of boys to girls in clinic samples suggest that Jamaican girls may not be receiving adequate services. Age X within subjects interactions revealed higher teacher reported problem scores for young adolescents, reflecting possible developmental changes within the classroom context and teachers’ low thresholds toward these problems. The d statistic revealed base rate syndrome, internalizing, externalizing, and total problem score differences in most Jamaican vs US sub-samples. In addition to the non-CBCL problems observed in earlier studies, these findings clearly indicate a need to ascertain syndrome structure and other psychometric properties of the Jamaican instruments.  相似文献   
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