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41.
The tourism industry can negatively affect wildlife, plants and natural ecosystems through habitat destruction, pollution, over-exploitation of natural resources and visitor impacts to sensitive ecosystems. One approach to mitigate such threats is the application of voluntary sustainability standards, supported by training of tourism enterprises and verified by external audits. The Rainforest Alliance standard defines 78 criteria (requirements) for sustainable environmental, social and business practices, and has been adopted by over 600 tourism enterprises – including hotels, lodges and tour boats – in 12 countries. We examined the performance of 106 hotels in six Latin American countries against 29 of the sustainable tourism criteria most directly related to biodiversity conservation. Independent audits were used to assess hotel performance at baseline followed by a repeat assessment after training, about two years later. Mean conformance with the 29 biodiversity criteria increased significantly during this interval, from 44% to 58%. Improvements were greatest for businesses in the lowest third of performance at baseline (laggards) and smallest for hotels in the highest third (leaders). The results indicate that a voluntary sustainability standard and training program can serve both to recognize existing good actors and to drive incremental improvement in enterprises that were previously less sustainable.  相似文献   
42.
黑土典型区有机质高光谱预测模型   总被引:3,自引:0,他引:3  
土壤有机质(SOM)是鉴别土壤肥力的重要指标,是土壤肥力的物质基础,其含量预测模型研究对于土壤肥力评价、土壤碳库估算、土壤资源利用与保护具有重要意义。该文以黑龙江省黑土带典型区为例,采集区域土壤样本,基于有机质含量与土壤反射率的定量关系,对光谱反射率进行一阶微分和倒对数的处理,建立偏最小二乘法模型(PLSR)、一元线性回归模型和多元线性逐步回归模型。结果表明:(1)土壤有机质敏感波段位于650-750nm。(2)通过比较建模样本与检验样本的决定系数(R2)和均方根误差(RMSE)的大小,得到反射率和倒对数处理后的数据最优模型都为PLSR模型,一阶微分处理后的最优模型为多元线性逐步回归模型。(3)PLSR模型的建模效果优于回归模型,但其预测效果却并不理想。该研究将为改进土壤理化参数、遥感反演、土地质量评价等工作方法提供理论与技术支持。  相似文献   
43.
依据2014年8~10月对北京市488名消费者的问卷调查资料,运用二元因变量的Logistic回归模型,对影响消费者对森林认证标识认知的因素进行了实证分析。结果表明:影响消费者对森林认证标识认知的主要因素是职业、对森林状况的了解、信息渠道和通常对于标识的信任度。最后就如何提高消费者对森林认证标识的认知水平和信任程度给出了加大对森林认证及其标识的宣传力度;充分利用多种宣传渠道展开对森林认证及其标识的宣传;增强国人的森林资源危机意识;更多地组织保护森林资源的活动;积极开拓国内森林认证产品市场;加大对森林认证产品的监督管理;消费者应增强自身的环保意识、绿色消费意识和责任意识等建议。  相似文献   
44.
45.
The purpose of this study was to explore the relationship between mandatory food safety training and certification and inspection results of chain restaurants and independent restaurants, using current food safety inspection results of food service establishments in Central Florida. More specifically, this study examines whether there is any statistically significant difference in the violation frequency among chain and independent restaurants. Reducing the risk of any foodborne illness is a critical strategy that industry stakeholders should pursue in an area dominated by tourism such as Orlando, Florida. A one-way ANOVA was used to determine the differences between the two types of restaurants. Findings indicate that there is significant difference between chain and independent restaurants for critical violations. No difference was found when comparing chain verses independent restaurants for non-critical violations.  相似文献   
46.
Abstract

This paper explores why and how ecommerce firms differentiate their products and services. Consumers who shop online are able to do quick and easy comparison shopping, including shopping in an active market for used goods. Since online product search and price comparisons are faster, easier, and involve fewer shopping costs, firms who sell online must differentiate their products and services to a greater extent than those who do not sell online. These product and service differentiations may be certified and rated by host shopping sites and by outside ratings companies.  相似文献   
47.
Previous studies, as well as market sales data, show some consumers are willing to pay a premium for redundant or superfluous food labels that carry no additional information for the informed consumer. Some advocacy groups have argued that the use of such redundant labels is misleading or unethical. To determine whether premiums for redundant labels stem from misunderstanding or other factors, this study seeks to determine whether greater knowledge of the claims - in the form of expertise in food production and scientific literacy - decreases willingness to pay for redundant labels. We also explore whether de-biasing information influences consumers’ valuations of redundant labels. An online survey of 1122 U.S. consumers elicited preferences for three redundantly labeled products: non-GMO sea salt, gluten-free orange juice, and no-hormone-added chicken breast. Respondents with farm experience report lower premiums for non-GMO salt and no-hormone-added chicken. Those with higher scientific literacy state lower premiums for gluten-free orange juice. However, after providing information about the redundancy of the claims, less than half of respondents who were initially willing to pay extra for the label are convinced otherwise. Over 30% of respondents counter-intuitively increase their premiums, behavior that is associated with less a priori scientific knowledge. The likelihood of “overpricing” redundant labels is associated with willingness-to-pay premiums for organic food, suggesting at least some of the premium for organic is a result of misinformation.  相似文献   
48.
In agricultural landscapes farmers have a large impact on biodiversity through the management decisions they apply to their land. Farmers’ perceptions of biodiversity and its different values influence their willingness to apply biodiversity friendly farming practices. The results of a discourse-based, deliberative biodiversity valuation are presented in this paper. Organic and conventional farmers’ perceptions of the different values of biodiversity were analyzed across three European countries. Focus group methodology was used to explore how farmers perceive biodiversity and how they assess its values.Our results suggest that farmers’ perceptions of biodiversity are strongly embedded in their everyday lives and linked to farming practices. Besides recognizing the importance of species and habitat diversity, farmers also acknowledge wider landscape processes and attach value to the complexity of ecological systems. Organic farmers tended to have a more complex and philosophical approach to biodiversity and they were relatively homogeneous in this aspect, while conventional farmers showed larger heterogeneity. Ethical and social values were important for all farmers. Economic value was more dominant in the conventional focus groups.The discourse based deliberative valuation method is worth applying in relation to biodiversity for two reasons. First, this method is able to reflect the heterogeneity of non-scientist participants and the context in which they are embedded, which both have a great impact on the results of the valuation. Second, deliberation upon the importance of biodiversity makes possible to understand the competing perceptions of biodiversity and to include different value aspects in the valuation process. The policy oriented consequence of the research can be drawn from the observation that farmers have a strong acknowledgement of ethical and social biodiversity values. This suggests that soft policy tools could also foster biodiversity sensitive farming methods, complementary to mainstream monetary incentives.  相似文献   
49.
This paper summarizes the results of personal exposure monitoring and estimates the risk from exposure to 18 volatile organic compounds compared with health criteria set by the US Environmental Protection Agency. In study 1, personal exposure levels and outdoor air concentrations were compared, and in study 2, personal exposure levels and the corresponding indoor air concentrations were compared. From these studies, it was concluded that personal exposure to volatile organic compounds depended markedly on indoor air quality and that handling of compounds increased personal exposure markedly. Risk estimations indicated that chloroform in tap water, benzene from cigarette smoke and p -dichlorobenzene from household insecticide needed caution.  相似文献   
50.
ISO14000认证与企业管理   总被引:2,自引:0,他引:2  
章简单明了地介绍了ISO14000认证的发展历程和基本知识,阐述了ISO14000标准的实施,既是为了保护人类生存发展的需要,也是实现两个根本转变的需要,同时也是为了促进国内外贸易,实现企业管理现代化的需要。ISO14000认证必将对未来世界各国企业管理造成深远影响。  相似文献   
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