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101.
Reproducibility of body temperature response to standardized test conditions when assessing clothing
《Ergonomics》2012,55(5):1057-1066
Abstract The traditional use of core temperature to assess the thermal effects of clothing has recently been questioned. The purpose of this study was to assess the reproducibility of body temperature in five subjects (mean age, 226 ± 1-5 yrs) wearing either athletic clothing or a chemical protective overgarment while exercising at 20°C and at 40°C. The exercise was preceded by a 1 h adaptation period in a controlled environmental chamber. Results indicated that mean group change in rectal temperature (δTr ) appeared to be reproducible for both garment ensembles at 20°C but not at 40°C. For mean change in oesophageal temperature ( δToes ) at 20°C, reproducibility was obtained for the overgarment but not for the athletic garment; at 40°C, mean δToes appeared to be reproducible with both garments. However, when individual responses were examined, there was little reproducibility for either δTr or δToes . In addition, these measurements failed to show differences in the types of clothing worn. It was concluded that the use of core temperature to assess heat stress imposed by wearing clothing during exercise may lead to erroneous conclusions. 相似文献
102.
We studied the content of the team mental model with a case study about a successful online game team. This team was formed by high-ranking managers in a large raid guild to conduct a raid in War of Worldcraft. They were interviewed with a set of 5-W questions developed according to the conceptualizations of team mental model (Levine & Moreland, 1991). Toward the interview protocol, a content analysis was conducted with two-cycle coding method from exploratory to explanatory and a hierarchical framework from code, category, theme, to theory were generated to describe the team mental model. In the first cycle, 17 codes were extracted from participants' own wording for concepts that were shared by whom controlled various gaming characters. These codes are knowledge convergence about the problem at-hand, actors, events, affects and outcomes – what the core gamers have experienced through the collaborative gaming process. In the second cycle, coding was guided by learning theories. Six categories, mingled from 17 codes, showed collective knowledge of co-work process, leaders' works, work under supervision, seeking joint fun, relationship oriented, and balance between extrinsic-intrinsic motivations. From 6 categories, two themes were synthesized: the team (1) performed “joint hard work” for (2) seeking “joint hard fun.” The first theme comprised declarative and procedural knowledge representations and we consider it to be the commonality between this game team and ordinary work/learning teams. The second theme was composed of affective and cognitive evaluation components about intrinsic motivation which is in accordance with Self-determination theory (SDT, Deci & Ryan, 2000). In general, “Jointly hard work for hard fun” is the gist content of the team mental model. We found ample evidences that members explicitly recall shared motivational beliefs of team mates and emotional–motivational events in gaming. Based on the results of this study, several implications have been addressed for teachers to enhance students' intrinsic motivation in conducting quality Computer-Supported Collaborative Learning. Future studies are needed to further explore the relationship between the quality of team mental models and team-level performance. 相似文献
103.
This study investigates the (de)mobilizing influences of political (dis)agreement in the news and in political discussion on political attitudes and participation in new information environments. Results demonstrate the mediating functions of political ambivalence in that exposure to proattitudinal news reduces ambivalence and thereby promotes political participation, whereas exposure to counter-attitudinal news increases ambivalence and thereby discourages participation. Importantly, the effect of exposure to counter-attitudinal news on ambivalence was moderated by heterogeneous discussion networks on social network sites, such that the combination of exposure to counter-attitudinal news and to heterogeneous discussion networks amplifies ambivalence additively, and thereby augments the tendency toward demobilization. These results are interpreted as suggesting that changing media contexts may lead to complex roles of news and political discussion. 相似文献
104.
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106.
Using the structural equation modeling method (N = 811), this study explores the structural relationships among online news consumption, political participation and social trust, with a focus on the mediating effects of online users’ deliberative perceptions and news-related online interactive activities. The analysis confirms that users’ perceptions of online deliberation exert a significant mediating effect on users’ levels of news consumption, political participation, and social trust. Users’ interactive civic messaging behaviors, on the other hand, solely enhance participatory intentions. The findings also show that the consumption of political news and the consumption of entertainment news have different effects on users’ perceptions of online deliberation, social trust, and political participation. Specifically, while political news has a direct and relatively strong influence on participation, entertainment news has a limited and indirect effect on participation. Online interactive activities are negatively associated with users’ perceived competency for online deliberation. Further implications of the study are also discussed. 相似文献
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108.
建设智慧城市已被许多城市视为城市发展新动力,智慧城市的规划与建设问题的研究具有十分重要的意义.通过阐述智慧城市产生的原因和动力、智慧城市建设的本质和发展趋势,分析世界范围智慧城市的关键点及上海智慧城市建设的着力点,提出智慧城市规划与建设的工作指导原则. 相似文献
109.
The objective of this study is to show that the core competence approach has validity when applied to construction. The focus is on the analysis of the fit between market strategies of firms in the building industry and their core capabilities. Certain strategies require specific core capabilities and key external and internal conditions supporting these capabilities. The resource-based approach focuses on the conditions in a firm, the internal capabilities, and supports a core capability that is demanded. The network literature will be related to external conditions that support a core capability of a firm active in a certain market. In a multiple case study, firms are analysed that are involved in different stages of the building process. The case studies demonstrate firms with consistent patterns of market strategies, core capabilities, and supporting internal and external conditions. The specific core capability of the firm under investigation determines the types of external and internal conditions that are critical. 相似文献
110.
回弹法检测高强混凝土强度宜优先采用高强回弹法,必要时可采用钻芯法进行修正。本文介绍了回弹法检测高强混凝土强度在建筑工程质量检测实践中的运用。 相似文献