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排序方式: 共有96条查询结果,搜索用时 31 毫秒
51.
Pricing China's irrigation water   总被引:1,自引:0,他引:1  
Many development agencies and other actors are advocating that China adopt a system of water markets or of high water prices in order to resolve the inefficiencies of irrigation agriculture and to supply sufficient water for growing urban and industrial uses. We argue that this proposal rests on a series of propositions: that the price of water is too low to encourage farmers to be efficient; that farmers are not charged volumetric prices and so are not encouraged to conserve water; that water is scarce largely because farmers are profligate in their use of water; and that proper pricing of water will not affect equity. None of these contentions is true. Farmers have to pay not only the official charges for water but also the much higher costs of pumping it onto their fields. Once pumping is included, farmers are paying prices that are volumetric. Furthermore, the inefficiency of farmers arises in large part from the manner in which water is delivered to them: the system offers no rewards for care in the use of water and instead rewards greed. And, finally, although it might be true that higher prices do not affect equity within a village, in fact they would have substantial effects on inter-sectoral equity, with farmers becoming worse off in comparison to urban dwellers. The paper concludes by sketching a more appropriate scheme for raising the efficiency of use of irrigation water.  相似文献   
52.
基于GIS的连锁企业商品配送服务   总被引:2,自引:2,他引:0  
主要研究了基于GIS的连锁商业企业的商品配送服务信息系统中的一个基本问题———如何根据居民点的服务请求确定配送商品的连锁商店。首先根据引力模型对连锁商店的服务域进行了讨论,在忽略了连锁商店的规模影响的基础上,导出了Voronoi多边形的商店服务域,并确定了由最邻近居民点的连锁商店提供商品配送服务的原则。于是问题转化为如何快速计算最邻近居民点的连锁商店的技术问题。我们提出了Voronoi多边形空间查询的新方法,通过与点对欧氏距离、缓冲区结合欧氏距离两种方法的比较,证明了Voronoi多边形空间查询的高效率,新方法的应用显著地提升了应用系统的效率。  相似文献   
53.
The abatement potential of wind technologies on ships is estimated to be around 10–60% by various sources. To date there has been minimal uptake of this promising technology, despite a number of commercially available solutions that have been developed to harness this free and abundant energy source. Several barriers have been referred to in the literature that inhibit uptake of energy efficiency measures in shipping. This paper provides a systematic analysis of the viability of wind technology on ships and the barriers to their implementation, both from the perspective of the technology providers and technology users (ship owner–operators), using the survey and the deliberative workshop method. The data generated from these methods is analysed using the qualitative content analysis method. The results show that whilst there is renewed interest in wind power, there are several common economic barriers that are hindering the mass uptake of wind technologies. Our analysis shows that third party capital is a plausible solution to overcoming the cost of capital, split incentives and information barriers that have contributed to inhibiting the uptake of wind technology in the shipping industry.  相似文献   
54.
After the US withdrawal from the Kyoto Protocol and the extension of national quotas in the Bonn and Marrakesh agreements, meagre environmental effects and a low price of emission permits are likely to be the outcome of implementation. This paper attempts to analyze this scenario, mainly in relation to the Russian case. I discuss on the basis of certain key assumptions the strategic options open to the supply side of the permit market and Russia's potentially incompatible interests as a producer of oil and gas on the one hand and a dominating seller of emission permits under the Kyoto Protocol on the other. The analysis shows that Russian oil and gas interests are likely to boost Russia's inclination to sell permits, ultimately resulting in lower permit prices.  相似文献   
55.
Although the disaggregation of consumers is crucial in understanding the fragmented markets that are dominant in many developed countries, it is not always straightforward to carry out such disaggregation within conventional retail modelling frameworks due to the limitations of data. In particular, consumer grouping based on sampled data is not assured to link with the other statistics that are vital in estimating sampling biases and missing variables in the sampling survey. To overcome this difficulty, we propose a useful combination of spatial interaction modelling and microsimulation approaches for the reliable estimation of retail interactions based on a sample survey of consumer behaviour being linked with other areal statistics. We demonstrate this approach by building an operational retail interaction model to estimate expenditure flows from households to retail stores in a local city in Japan, Kusatsu City.   相似文献   
56.
湖北省海外旅游市场开发研究   总被引:2,自引:0,他引:2  
本文主要从湖北省入境旅游市场状况考察入手,重点分析当前湖北面临的国际旅游市场形势,找出存在的问题,预测发展趋势,明确市场目标和几个关系,提出相应的市场开发战略,以期促进湖北旅游市场理论与应用的研究。  相似文献   
57.
赵志广 《吉林地质》1998,17(1):63-66
矿产资源是生产力系统中的重要构成在素,人类自进入文明社会后,生产力的存在和发展都与太产资源的开发利用息息相关,矿产资源已日益成为生产力系统的内在要素,矿产资源的开发利用是生产力发展的必要条件,更是维系现代生产力可持续发展的关键。矿产资源的开发是生产力发展的结果和标志,同时,矿产资源的开发利用既能够促进生产力的发展,又对生产力的发展产生限制和制约作用。开发利用资源是发展生产力,保护矿产资源就是保持生  相似文献   
58.
The production and trade of agricultural commodities, such as cocoa, have important impacts on farmer livelihoods and the environment, prompting a growing number of companies to adopt public commitments to address sustainability issues in their value chains. Though trading companies, who handle the procurement and export of these commodities, are key actors in corporate sustainability efforts, cross-country data on their identity, market share, and adoption of sustainability commitments is lacking. Here, we address this gap for the cocoa sector by compiling detailed shipping data from eight countries responsible for 80% of global cocoa exports, developing a typology of trader types, and assessing their adoption of sustainability commitments. We find that cocoa trading is a highly concentrated market: seven transnational companies handled 62% of the global cocoa trade, with even larger shares in individual cocoa producing countries. The remaining 38% of exports were handled by domestic trading companies and farmer cooperatives. Overall, the adoption of public sustainability commitments is low. We estimated that just over one quarter (26%) of cocoa is traded under some form of sustainability commitment, with gaps arising from their exclusion of indirect sourcing, low adoption rates by domestic traders, and commitment blind spots, notably on forest degradation and farmer incomes. Low rates of traceability and transparency pose a further barrier to the broadscale implementation and monitoring of these commitments: one-quarter of traders report being able to trace at least some of their cocoa back to farmer cooperatives and only half of them openly disclose the identity of their suppliers. We discuss the opportunities and limitations of voluntary sustainability commitments in a highly concentrated market and argue that, to realize visions of sustainable trade, the gaps in commitment coverage must be closed by extending current efforts to smaller traders and indirect suppliers. However, companies must support, coordinate and align with government efforts so that voluntary initiatives are ultimately rendered more transparent and accountable.  相似文献   
59.
稀土元素因其丰富的光、电、磁、热特性被广泛应用于传统工业领域及新兴产业领域,稀土资源被多数国家认定为是战略性资源或关键性矿产资源。我国是稀土资源大国,无论从储量、产量还是消费量上来看我国都居于世界前列。从资源管理角度我国稀土资源战略定位可以概括为有效保护和合理利用稀土资源,保障资源供应安全;坚持国家利益最大化,优先满足国内应用需求;节约集约利用资源,在开发利用的同时保护生态环境。本文初步探讨了以计划为基础和以市场为导向的两种实现稀土资源战略的实施路径,并就此提出稀土产业发展的相关建议  相似文献   
60.
如何打造电视气象节目的优质品牌   总被引:18,自引:0,他引:18  
容军 《广西气象》2006,27(3):70-72
从市场和传播学的观点出发,围绕着电视气象节目的特点,提出了打造电视气象节目优质品牌的一些建议。  相似文献   
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