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201.
This study was designed to evaluate different approaches to the protection of the environments of coastal recreation sites in and around Antalya, Turkey. Data was collected by means of a survey of coastal recreation sites and six categories were evaluated: environmental protection, infrastructure facilities, water conservation, energy conservation, waste management, and protection of the natural environment. The results indicated that there was a clear motivation among site managers or authorities for environmental protection (p < .05), infrastructure facilities (p < .001), water conservation (p < .05), energy conservation (p < .05) and the protection of the natural environment (p < .001) but waste management was not accorded a priority. The quality of coastal recreation largely relies on the attractiveness and naturalness of the environment. Although good quality site management largely depends on the awareness and willingness of individual site managers, more proactive approaches toward better environmental protection of recreation sites along the Turkish Mediterranean coast might be effective in improving their sustainable use, particularly in the absence of proper site planning.  相似文献   
202.

I investigated the impact of human trampling on Fucus gardneri populations at Cattle Point on San Juan Island, Washington. I hypothesized that damage to Fucus fronds would differ depending on hydration state of the plants, number of trampling steps, and time. Over a two-day period, two levels of trampling treatment, 100- and 200-steps, were applied to 18 plots on two rocky intertidal benches. Detached biomass resulting from trampling was collected each day, weighed to the nearest 0.1 gram, re-hydrated overnight in seawater, and re-weighed in order to calculate biomass removed as a function of mean percent Fucus within each plot. Damage to plants did not differ with the hydration state of Fucus. However, loss of biomass did increase with treatment level, with 222 g of Fucus fronds removed from one 100-step plot up to 1302 g removed from a 200-step plot. Percent cover decreased differentially with treatment level, ranging from 10 percent cover in a 100-step plot up to 85 percent loss in a 200-step plot. To determine the effect of hydration on loss of Fucus biomass, future studies should include plants with a higher degree of desiccation than those in this study, more samples to increase the power of the analysis, and a longer period to detect changes due to time.  相似文献   
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204.
The first attempt to implement the 1999 California Marine Life Protection Act (MLPA) to establish marine protected areas (MPAs) ended contentiously in 2002. The initial MLPA process is examined by a statutory analysis and an analysis of stakeholder network relationships and beliefs. The failure of the initial MLPA process can be understood by a combination of factors: (i) Insufficient financial support from the California State government; (ii) Unclear, unranked and inconsistent statutory objectives; (iii) The application of a science-based process that excluded affected stakeholders; (iv) Implementing officials who lacked expertise in designing and managing political processes; and (v) A community of stakeholders who were polarized into coalitions of proponents and opponents of MPAs. The article concludes by discussing limitations of its methods and analysis and by offering strategies for learning from policy failures.  相似文献   
205.
Abstract

Natural coastal accretion in the United States occurs at river mouths, spits across embayments, inlets, capes and cuspate forelands, and pocket beaches. Human‐induced accretion occurs updrift of groins and jetties, landward of breakwaters, and in locations which are artificially nourished. Coastal accretion is usually temporary (years to tens of years). Erosion may occur due to deflection of streams and tidal current channels or to changes in sea level, weather patterns, or sediment budgets. A focus on ownership disputes or use of accreted land draws attention away from the long‐term problem of the development of land which may be subject to future erosion. Control mechanisms should be in place to direct development on accreting shorelines to make more effective use of the resource.  相似文献   
206.
连云港港30万吨级航道二期工程航道疏浚施工项目LYG-302-H1.1标段施工过程中,绞吸船多次发生堵管现象,影响施工效率。为避免事故频繁发生,通过整理事故多发地土质资料,分析土层特性及堵管原因,对此类难挖地段的土质指标进行归纳总结。结果表明:绞吸船施工难挖地段土层分布不均匀;同一高程下,黏土层中含有黏质粉土和砂质粉土,且混有离散的钙质胶结物;标贯击数大于20击。  相似文献   
207.
The planning and implementation of a multimodal transportation system in the Holy City of Makkah to handle the huge volumes of pilgrims to the City is not a straightforward mission, as Makkah poses numerous challenges including its unique seasonal demand patterns, mountainous terrain, and limited space. Aerial ropeway transit (ART), a promising transport technology solution, could be an important component of this system. This paper presents the results of a technical and economic feasibility study to explore the potential of introducing ART service in Makkah. The study reveals that, overall, ART service on some corridors in Makkah is technically feasible, and with some necessary enforcement measures to attract ridership could become a profitable transportation investment. Specifically, the study recommends using ART for special user groups and service/emergency crews during peak seasons and opening ART to the public as a premium service during the off-peak season.  相似文献   
208.
环境风险是涉及饮用水水源保护区的公路项目营运期最主要的环境问题。文章从竣工环保验收实践角度,总结了广西公路项目穿越饮用水水源保护区的环境风险防范中存在的主要问题,并提出了相应的设计优化建议和对策,旨在为妥善解决公路建设与饮用水源保护间突出矛盾提供技术支持,为公路建设、设计单位等有关单位防范环境风险提供技术参考。  相似文献   
209.
文章阐述了钦州市城乡公交客运发展现状及问题,分析了钦州市城乡公交客运一体化的必要性和可行性,提出了实现城乡公交客运一体化的具体措施。  相似文献   
210.
根据山区灾害多发区段线路方案优选问题具有多因素和模糊性的特点,在建立多级模糊综合评价的指标体系的基础上,采用层次分析法合理确定路线方案各影响因素及其各子因素的权重,运用模糊数学理论,建立了山区灾害多发区段路线方案的二级模糊综合评选的数学模型,提高了山区灾害多发区段路线方案评选的客观性和科学性.并以山地灾害多发的迫隆藏布流域段为实例进行了研究,证明了这种方法的合理性和有效性.  相似文献   
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