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991.
Along with the growing boating population and the number of boats in use on limited inland waterways, boater expectations of setting density, safety perceptions, and the associated impacts on their experience (e.g., satisfaction) are becoming increasingly important. The primary purpose of this article was to explore a recreational boating crowding–satisfaction model derived from previous work using safety and enjoyment as mediating variables. We also tested our crowding–satisfaction model among day and overnight users. Our analysis revealed no significant difference between day and overnight users for any of the relationships tested in our model. Our final model indicated as respondents’ expectations for seeing people increased along with their feelings of being crowded, they were more inclined to consider the conditions on the lake as being unsafe. They were also more inclined to indicate that the number of people they had seen on the lake detracted from their boating experience. Respondents’ satisfaction was tied to their perceptions of crowding. Mediating variables illustrated that the relationship was conditioned by perceptions of safety and enjoyment. Analysis of the indirect effect observed in our study illustrate that when the number of people seen on the lake exceed respondents’ expectations, their perceptions of safety and enjoyment both decline, resulting in lower satisfaction. These findings have implications for managing recreational boating use on inland lake systems. Given the role played by expectations in our model, efforts to communicate with boaters about conditions on these waterways is important for helping them plan their boating experience and avoid situations they consider unsafe or unsatisfactory.  相似文献   
992.
Tourism and landscape are interdependent concepts. Nature- and culture-based tourism are now quite well developed activities and can constitute an excellent way of exploiting the natural resources of certain areas, and should therefore be considered as key objectives in landscape planning and management in a growing number of countries. All of this calls for careful evaluation of the effects of tourism on the territory. This article focuses on an integrated spatial method for landscape analysis aimed at quantifying the relationship between preferences of visitors and landscape features. The spatial expression of the model relating types of leisure and recreational preferences to the potential capacity of the landscape to meet them involves a set of maps showing degrees of potential visitor satisfaction. The method constitutes a useful tool for the design of tourism planning and management strategies, with landscape conservation as a reference.  相似文献   
993.
Field research was carried out to assess the effects of the application of reclaimed municipal wastewater on rice cultivation in Thessaloniki, Greece during a 2-year period (1999–2000). Effects on production cost, soil composition, and health risk were examined. A randomized complete block design was used for the paddy field with three treatments and four replicates. The treatments were (1) river irrigation water with N–P fertilization, (2) reclaimed wastewater irrigation with surface N fertilization, and (3) reclaimed wastewater irrigation without fertilization. The results showed that the total production cost decreased 8.8% and 11.9% by applying the second and third treatments, respectively, compared to the first treatment, without significant differences in the agronomic and rice quality traits. Soil composition showed discrepancies between the 2 years and the three treatments, whereas the pathogens of the reclaimed wastewater and rice tissues posed a low human risk when taking the needed precautions.  相似文献   
994.
王鹏  甘静  温馨 《资源开发与市场》2009,25(10):900-902,913
风险投资为中小企业特别是高新技术企业发展壮大提供了资金支持和保障.成都市风险投资现状与国内先进地区相比既有很大差距,又不符合成都区域经济的发展水平.从政府行为的角度,提出构建创业投资服务信息平台作为成都风险投资发展的重要一环,并从内在需要、外部机制和功能实现三个方面对其进行了详细的探讨.  相似文献   
995.
注浆法治理公路黄土暗穴病害的试验研究   总被引:1,自引:1,他引:0  
注浆法是公路工程中治理暗穴的一种新方法.针对湿陷性黄土地区公路工程中大量发育的暗穴病害,通过室内浆液材料物理力学性能试验与工程现场模拟注浆效果试验,分析了以水泥为主剂的注浆材料在不同配合比情况下治理公路工程中暗穴的效果.室内外试验结果分析表明:浆液水灰比在2.5∶1~1.5∶1之间较为适宜;在不影响路基路面的正常压力下有效的加固半径是1.0 m~1.5 m;在特殊情况下为了使浆液快速凝结可以加入一定量的水玻璃作为速凝剂;可以采用二次注浆加强治理的效果.  相似文献   
996.
对广西南宁膨胀土进行了一系列室内压缩蠕变试验,得出了相应的蠕变曲线.运用K-H体模型和Bu体模型进行对比研究,确定了正常应力条件下非饱和南宁膨胀土的粘弹性模型和各流变常数,提出了正常应力条件下南宁膨胀土的本构方程及蠕变方程.为膨胀土工程设计和分析提供可靠的理论依据.  相似文献   
997.
综述了一种新型分离技术——膜蒸馏技术在石化废水处理领域的应用现状,重点介绍了在高盐度废水处理和挥发性有机物废水处理两个方面的进展;指出膜蒸馏应用过程中存在的主要问题是膜污染;预测了膜蒸馏及其集成技术在废水处理领域的发展前景。  相似文献   
998.
基于数字图像处理技术的金相分析研究   总被引:2,自引:0,他引:2  
姜蓬  蒋勇  邱榕  廖光煊 《火灾科学》2009,18(3):163-167
采用和改进了人际交互式图像分割算法Live-wire,对电气火灾中的典型火烧金相图和一次短路金相图进行处理,结合数字形态学操作,精确提取了两类金相图中的典型胞状晶和柱状晶结构;分析和讨论了多种结构描述子对晶格分类的作用,结果表明,离心率和晶格标记方差两个描述子能有效区分两类晶格结构;采用聚类分析和Fisher判别法,实现了对两类金相图的自动分类.  相似文献   
999.
安全工程学科发展与专业办学思路的思考   总被引:6,自引:5,他引:1  
迎合安全工程教育的蓬勃发展,结合上海应用技术学院安全工程专业建设的历史以及人才培养现状,分析了上海经济形势和学科专业教育教学方向,总结了安全工程学科的探索思路以及办学拓展方向,提出了专业课程模块方向与课程设置,供安全工程教育工作者参考.  相似文献   
1000.
On account of the background of China’s “new normal” characterized by slower economic growth, this paper analyses the low-carbon economy status quo in the Beijing–Tianjin–Hebei region and empirically investigates the relationship between carbon dioxide (CO2) emissions and its various factors for China’s Beijing–Tianjin–Hebei region using panel data econometric technique. We find evidence of existence of Environmental Kuznets Curve. Results also show that economic scale, industrial structure, and urbanization rate are crucial factors to promote CO2 emissions. However, technological progress, especially the domestic independent research and development, plays a key role in CO2 emissions abatement. Next, we further analyze the correlation between each subregion and various factors according to Grey Relation Analysis. Thereby, our findings provide important implications for policymakers in air pollution control and CO2 emissions reduction for this region.  相似文献   
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