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Susan Dente Ross 《广播与电子媒介杂志》2013,57(2):254-270
Video market entry options available to telephone companies under the Telecommunications Act of 1996 have First Amendment implications that will affect the constitutional value of telephone video. These entry options impose regulatory constraints upon providers and differ in potentials for provider speech, speaker access, and content diversity. The author concludes that the Act's open video system option best advances First Amendment interests in increased diversity of and access to speech. 相似文献
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Edward Kinfai Tse 《文物保护研究》2016,61(1):31-36
Efficient air-conditioning systems facilitate climate control in modern museums, libraries, and archives. The climate in Hong Kong is typically hot and humid, so the survival of collections is highly dependent on 24-hour air-conditioning systems to maintain the desired environment in repositories of archives and books, or artefact stores. The continuous operation of such systems in turn relies on a number of factors, such as uninterrupted electricity supply, an active maintenance programme, daily monitoring of their performance and quick response to irregularities as well as backup or alternative systems to support the air-conditioning load in case they are down for servicing. From the risk management point of view, unlike the latter four factors, electricity supply is an external factor that cannot be guaranteed. Fluctuation in the power level that results in stoppage of air-conditioning equipment is not uncommon even in well-developed countries. Long power outages could be catastrophic as they might lead to irreversible damage to collection items as a result of fast, large, changes in temperature and relative humidity (RH) towards the external environment if the air-tightness or hygrothermal stability of the storage are not good enough. Understanding storage environmental stability, especially during electrical power disruptions, is an essential part of the preservation measures and disaster preparedness necessary to protect valuable collections in cultural heritage institutions in the region. 相似文献
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Mooses and colleagues suggest that running economy alone does not explain superior distance running performance in elite Kenyan runners. Whilst we agree with the multi-factorial hypothesis for Kenyan running success, we do not believe that running economy can be overlooked to the extent that it was based on this particular study. Based on the methods used and the range of athletes tested, in this response letter we question whether this study provides any basis for downplaying the influence of running economy or suggesting that other factors compensate for it to enable superior performance. 相似文献
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David S. Haydon Ross A. Pinder Paul N. Grimshaw William S. P. Robertson 《Sports Engineering》2016,19(3):177-184
Limited recommendations of wheelchair configurations for court sports have been identified in the published literature. To accommodate the wide range of impairments in wheelchair rugby, players are given a point score that reflects their impairment. Players have regularly been grouped as high-, mid-, or low-point players in research, with high-point players having greater levels of muscle function compared with other classifications. This research documented the wheelchair configurations of elite Australian wheelchair rugby players across classification groups. Significant differences (p < 0.05) were found for increased seat height and decreased seat depth for high-point players compared with low- and mid-point groups, respectively. Low-point players displayed reduced wheelchair mass compared with high- and mid-point players, as well as increased frame length. Camber angles showed no significant differences across the classification groups. The incorporation of anthropometric measures, such as the elbow angle at the top dead center, was also investigated. While elbow angle showed no significant differences, seat height-to-total arm length ratio was higher for high-point players. Participants also completed surveys detailing their perception of the effect of altering wheelchair configurations. It is suggested that wheelchair configurations should consider an individual’s anthropometrics, impairment, training history, and court role to promote optimal performance, with predictive modeling having the potential to reduce the associated time and cost. 相似文献
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Chamila Nishanthi Edward David Asirvatham Md. Gapar Md. Johar 《Education and Information Technologies》2018,23(6):2587-2606
Blended learning emerged as the most popular instructional design strategy in the field of education since last decade to present date. In fact, it is well acknowledged that blended learning approach significantly elevate students’ engagement and competency in learning process. Despite immense potentiality, many countries are still lag behind adopting this instructional design, such as Sri Lanka. Therefore, the primary aims of this study are two fold, (a) to investigate the effect of blended learning and learners’ characteristics on students’ competence and (b) to investigate the effectiveness of blended learning in teaching Oriental Music. This study mainly carried out among the senior secondary schools students at Colombo, Sri Lanka. A mixed methods, experimental and survey, were carried out to test the effectiveness of blended learning and identifying the important factors for enhancing students’ competence in learning Oriental Music. Results of independent sample t-test confirmed that blended learning is effective in terms of improving students’ performance in learning Oriental Music. Similarly, regression analysis confirmed that attitude and motivation are the two most important determinants for improving students’ competence. This study fulfilled an existing research gap by utilizing blended learning to teach highly traditional abstract art. Results of the study contributes to the curriculum designing field with novel ideas to adapt in hybrid instructions to teach secondary level students effectively. The curriculum designers will make use of these findings during innovation and future researcher would be benefitted to overlook more possible platforms to deliver music instructions. It will help them to understand how their set objectives have been achieved in technology integrations and seek for improvement where necessary. 相似文献
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This paper addresses a dynamic portfolio investment problem. It discusses how we can dynamically choose candidate assets, achieve the possible maximum revenue and reduce the risk to the minimum level. The paper generalizes Markowitz's portfolio selection theory and Sharpe's rule for investment decision. An analytical solution is presented to show how an institutional or individual investor can combine Markowitz's portfolio selection theory, generalized Sharpe's rule and Value-at-Risk(VaR) to find candidate assets and optimal level of position sizes for investment (dis-investment). The result shows that the generalized Markowitz's portfolio selection theory and generalized Sharpe's rule improve decision making for investment. 相似文献
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