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271.
湖泊旅游理论研究滞后于发展实践,系统性、针对性的研究不足,概念体系尚有待完善,研究框架尚未形成。论文采用文献分析法和系统归纳法,分析对比国内外湖泊旅游研究内容,展望未来研究趋势。结果表明:湖泊旅游资源评价与开发、湖泊旅游感知、湖泊旅游规划与管理、旅游者空间行为与旅游市场、湖泊旅游地演化、湖泊旅游影响是国内外湖泊旅游研究的主要内容,但研究时间、研究内容和研究方法存在较大差异,均未出现较明显的理论性和阶段性特征。从中国湖泊旅游发展及研究现状看,未来应加强新发展要素在湖泊旅游发展中的作用过程和机制研究、湖泊旅游地人地关系地域系统研究、流域尺度条件下湖泊旅游地管理研究,同时注重借鉴、吸收国际湖泊旅游发展和研究的有益经验。 相似文献
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273.
Hussain Mahamed Sahed Mostafa Mazarbhuiya Agnimitra Biswas Kaushal Kumar Sharma 《International Journal of Green Energy》2020,17(2):171-179
ABSTRACTVertical axis wind turbine (VAWT) is an economic and widely used energy converter for converting wind energy into useful form of energy, like mechanical and electrical energy. For efficient energy conversion in low wind speed and to have improved power coefficient of asymmetric blade VAWT, selection of optimum blade thickness is needed thus entailing its detailed investigation with respect to different operating wind speed conditions. Present study methodically explores the impact of thickness to chord (t/c) ratio on aerodynamic performance of a three bladed asymmetrical blade H-Darrieus VAWT at different low wind speed conditions by using 2D unsteady CFD simulations. The optimal t/c is obtained on the basis of maximum power coefficient and average moment coefficient of the turbine. The aerodynamic performance curves are obtained at different operating and t/c conditions and the performance insights are corroborated with the findings from the flow physics study to come to some concrete conclusions on the effects of the thickness to chord ratio. The present study identifies large blade curvature to create a large diverging passage on the blade suction surface as the prominent reason for aerodynamic performance drop at a high t/c ratio. 相似文献
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Aircraft accidents and incidents associated with visual flight into instrument weather conditions continue to account for a significant proportion of fatalities involving general aviation aircraft. The aim of this study was to examine pilot recounts of flights involving inadvertent or deliberate flight into Instrument Meteorological Conditions (IMC). Of the 251 responses that were examined, 145 pilots indicated that they had entered IMC inadvertently during a visual flight, while 93 had done so deliberately. Amongst non-instrument-rated pilots, two cohorts were identified whereby pilots who deliberately entered instrument conditions tended to have experienced the conditions previously, possess a comparatively greater tolerance of risk, experienced less anxiety during the event recounted, and perceive the risks associated with the transition into instrument conditions as relatively lower than those pilots whose entry into instrument conditions was inadvertent. These results are interpreted as confirmation of the need to address the problem of visual flight into instrument conditions from a number of different perspectives, taking into account experience and individual differences in risk tolerance. 相似文献
276.
Information source and valence: How information credibility influences earthquake risk perception 总被引:2,自引:0,他引:2
The present research aims at the relationship between information credibility and perception of seismic risk in a group of people living in severe disaster areas. 243 adult residents exposed to seismic hazard participated in a questionnaire study. With respect to four types of information which are generated by information sources and valence, participants were instructed to recall one type of the information they obtained respectively and rate the recalled information in terms of its credibility. After that, they were asked to report their seismic risk perception and all socio-demographic data were also collected. Regression analyses suggested that information credibility significantly influenced risk perception. Furthermore, the credibility of word-of-mouth and negative information were positively associated with risk perception. Meanwhile, risk perception was also affected greatly by the credibility of negative public information but not positive word-of-mouth information. It was clear that both information source and valence moderated the process and the latter exerted a stronger influence on it. The results were interpreted in relation to the elaboration likelihood model, accessibility-diagnosticity model, and other cognitive theories. The findings were discussed in terms of their general implications for the improvement of risk communication about earthquake related messages. 相似文献
277.
运用IPA分析法对武陵源旅游目的地形象感知进行了实证分析.研究表明,武陵源旅游目的地形象建立在过硬的基础设施之上,软件建设相对不足,旅游服务质量不稳定.从总体上看,武陵源旅游目的地形象与游客的预期还存在差距,其中民俗文化独特性、当地物价水平、旅游商品品质属于弱势项目,是今后建设的重点. 相似文献
278.
本文通过对旬阳县生态工业园区2011-2013年规模企业节能减排监管情况的全面评估,探索出了一条县域工业集中区节能减排精准化管理的新模式,为政府环境管理、决策提供了详实、准确的科学依据和计算方法.在县域工业集中区节能减排和基层环境管理工作中具有一定的借鉴和指导作用. 相似文献
279.
Yen-Lien Kuo 《Environmental Hazards》2016,15(4):311-326
This paper evaluates willingness-to-pay (WTP) for flood insurance and floodgate installation in Tainan, Taiwan, and finds that household flood precaution (observing the water level) has a minor effect in terms of increasing the WTP for flood insurance, rather than decreasing it. The reason for this is that people who have public flood protection nearby do not lower their WTP for floodgate and insurance, and those who live near the water source of floods and exhibit precautionary behavior have higher risk perceptions and intend to pay more. The adopted mitigation (having sandbags or other barriers) will not affect the intention to further mitigate or buy insurance. This also means that adverse selection in relation to flood insurance is not serious in the flood-prone area of Tainan. Households may be aware of the limitation of public flood protection though the precautionary behavior, and found that flood insurance can compensate for most of the flood damage. 相似文献
280.
气候变化背景下,适应城市极端天气风险不仅是政府的责任,也越来越需要公众参与。然而,对风险感知、适应感知和适应行为响应的影响因素,以及三者之间的内在联系还缺乏系统认识。通过问卷调研上海市居民发现:(1)风险感知可以促进适应感知,二者均与收入和教育水平等显著正相关。(2)与关注预警信息和使用防水防潮材料等个人适应行为相比,居民对集体行为的响应程度更高,如增加绿地面积和提高监测预警准确性等。(3)适应行为的影响因素可归纳为:信息通达性、社区归属感、适应意愿、适应激励、风险感知和适应感知,其中信息通达性和适应激励是显著提高个人适应行为的关键因素。 相似文献