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81.
基于粗糙集理论的经济圈交通枢纽灰色关联分析评价   总被引:1,自引:0,他引:1  
经济圈交通枢纽综合评价中存在信息不确定、定性评价指标较多的问题,而传统的评价方法虽然简单直接,但容易受到主观因素的众多干扰。提出了一种基于粗糙集的灰色关联分析综合评价方法,将基于粗糙集理论的指标赋权法与灰色关联综合评价相结合,通过粗糙集理论对指标进行约简并给出较为客观的指标权重,得出综合评价模型以及相应的算法;通过算例说明了该方法的有效可行。  相似文献   
82.
BRT运营服务水平的分析与评价对城市快速公共交通系统的规划与管理起着重要的指导作用。传统的评价方法其权重确定虽然简单,但往往受主观因素影响,鉴于此,采用粗糙集理论对指标进行约简得到各个指标重要性和较为客观的权重,结合物元分析法建立指标性能参数的评定模型,利用关联函数进行可拓分析,对快速公交运营服务水平进行可拓综合评价。通过实际算例来说明该方法的合理性和有效性。研究结果表明:基于粗糙集的 BRT运营服务水平可拓综合评价方法,能够对快速公交系统服务水平进行全面正确的综合评价。  相似文献   
83.
长江中游相对湿度的气候变化特征及其对航运的影响分析   总被引:1,自引:0,他引:1  
利用1965~2008年长江中游附近17个气象观测站点的相对湿度数据分析了长江中游相对湿度的气候变化特征.分析结果表明:长江中游年平均相对湿度在65%~85%之间,除个别站点外年平均相对湿度以及年高湿日天数均有减小的趋势;大部分站点6~8月份的相对湿度比其他月份要高,且与其他月份相对湿度的差值有增加趋势;高湿日天数在1/3以上,较西的站点7月份高湿日最多,较东的站点3月份高湿日最多;相对湿度与降雨量呈正相关,与蒸发量和日照时间呈负相关.相对湿度的这种变化对粮食、化肥等货物的运输是有利的.  相似文献   
84.
通过运用数理理论之AR模型,开展填方路基沉降的检评工作,完成了工后质量评定任务,并预测其未来的沉降程度及趋势.研究表明:应用数理理论方法得出的结论,不仅具有实用价值和增强了可靠性,而且兼有鲜明的主动、事前的特征.  相似文献   
85.
Relative sea-level rise will affect vulnerable coastal communities globally. Quantifying this effect on the coastal environment and infrastructure provides critical information that enables coastal managers to develop sustainable mitigation and adaptation measures. Modeling applications have enabled the past, present, and future trends in shoreline morphology to be investigated in detail. Predictive numerical models depend largely on the reliability of the input data. This article reports on using the Soft Cliff and Platform Erosion (SCAPE) numerical model to simulate future shoreline evolution trend in the central Accra coast in Ghana. The model input parameters include historic shoreline recession rates, wave data, tidal data, bathymetry, beach volume, beach topography, historic relative sea-level rise rates, and the shoreline orientation. The data fed the SCAPE numerical model which simulated the emergence of soft rock shore profiles over timescale of decades to centuries, to project future positions of the central Accra shoreline for the next 100 years under different scenarios of climate change. Simulated future shoreline positions overlaid on a 2005 orthophoto map of Accra enabled vulnerable areas and infrastructure at risk to be identified. It emerged that a highly populated community in central Accra will be inundated by 2065, while the Rivera beach resort will be eroded from 2035. A natural fish landing site in Osu (suburb in Accra) will be lost from 2045. The study has demonstrated that considerable ecological, economic, social, and national losses should be expected within the next century. Shoreline change management options should be explored to help mitigate the expected impact of the sea-level rise.  相似文献   
86.
Site selection is a key factor in any aquaculture operation, affecting both success and sustainability. Moreover, it can solve conflicts between different coastal activities, making a rational use of the coastal space. Geographical information systems (GIS) have become of increased significance for environmental planning and assessment mainly because of the need to compare a great number of spatially related data, and because it can be used to couple these spatial data with their attributes and overlay them. This study used GIS and related technology to build a spatial database using those criteria which were considered to have any influence in integrating marine fish-cage culture within the tourism industry in Tenerife. Criteria were grouped in three submodels (distance to beaches, nautical sports, and viewshed), which were combined to generate a final output showing the most suitable areas for cage culture development in coexistence with tourism. Most areas of the coastline of Tenerife were identified as being suitable (56%) or very suitable (46%), suggesting that marine cage aquaculture could be developed on the island in coexistence with the well-established tourism industry.  相似文献   
87.
Fifty-five percent of Georgia's developed coastline has been armored with various types of erosion protection devices. This article is about beach improvement projects at Jekyll Island that would operate under (a) a nourishment policy or (b) a retreat policy. Benefits are calculated from an intensive, on-site survey of beach visitors and the costs are calculated from observable sources. Two financing methods are considered: general revenue and user fee financing. The analyses imply recommending beach improvement as an effective policy within the considered time frame.  相似文献   
88.
Major impacts of climate change have been projected for tourism in Europe. Typically, these projections took general tourism activities such as sight-seeing and their climate requirements as their point of reference. The purpose of this study is to reassess the impact of climate change, by looking specifically at beach tourism in summer, a crucial market segment in Europe and more specifically in the Mediterranean. As beach tourism requires relatively high temperatures, relatively modest shifts in attractiveness are found. With respect to climate, the Mediterranean is likely to remain Europe's prime region for summer-time beach tourism for at least the next 50 years. Coastal managers in Mediterranean destinations are advised to focus some of their attention on other climate change impacts such as sea-level rise or water availability, and include environmental quality and diversification of activities in their deliberations. In non-Mediterranean regions, a promising strategy may be to focus on short- and medium-distance visitors who can take advantage of the new opportunities for beach tourism, and to explore the merits of seasonal climate forecasting.  相似文献   
89.
This study explores the relationship between Australian's attitudes toward climate change impacts on the Great Barrier Reef (GBR) and environmentally responsible behavior (ERB). We hypothesize that general attitudes toward climate change, subjective norms, and perceived behavioral control predict intended and reported behavior, and that attitude negatively influences constraints on adopting ERB. The moderating effect of residential condition (urban vs. rural contexts) was tested across these hypothesized relationships. We randomly selected 200 individuals from eight regions: Five within 50 km of the GBR Coastline and three from the Statistical Metropolitan Areas in Australia. We yielded 1,623 surveys by telephone interviews. Findings confirm our hypotheses and suggest the most important predictor of intentions is perceived behavioral control. The two groups of respondents (urban vs. rural) illustrate different relationships. This study offers insight on how managers of the GBR can effectively shape residents' behavioral tendencies that minimize human impacts on the natural environment.  相似文献   
90.
ABSTRACT

How vessel crews perceive safety on board (shipboard safety) is a useful indication for the general safety level. In this study a theoretical model was explored, involving factors that could possibly influence shipboard safety. Based on a survey questionnaire (n = 244), safety climate, shipowner efficiency demands and regulatory activities were investigated as influencing factors. Structural equation modelling gave support to the theoretical model and the findings illustrate that simultaneous involvement of various levels of the maritime system (crews, shipowners, regulators) can be effective for safety improvements. The study indicates that shipboard safety is affected by actions and prioritization by external actors through safety climate. It suggests that the maritime industry will profit from monitoring safety climate as part of the ongoing risk considerations, as a supplement to reactive parameters such as accident statistics.  相似文献   
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