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51.
信息资源共享系统可靠性模型的研究   总被引:3,自引:3,他引:0  
信息资源共享系统可以充分利用信息的传递性、共享性,支持异地协同工作,使人们获取信息更为经济、便利、迅速。信息资源共享系统有其自身的脆弱性,系统安全可靠是最重要、最基本的需求。提高系统可靠性,预防不可靠因素是信息资源共享系统设计的关键之一。笔者提出了信息资源共享系统可靠性的概念。由信息资源共享系统可靠性理论导出信息资源共享系统可靠度,建立了信息资源共享系统可靠性优化的多目标数学规划模型。为信息资源共享系统可靠性建立了定量分析方法。最后以可靠度、成本和时间3个优化目标为例,进行了计算、分析。为信息资源共享系统可靠性设计提供了新方法。  相似文献   
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With the rapid development of increasingly complex technology and large scale industrial projects, all kinds of safety problems become extremely intricate in daily safety management (SM). It is therefore indispensable to effectively collect, analyze, assess, and synthesize information that is relevant to accident risk. In this paper, the concept of the information literacy (IL) of professionals in SM is proposed, and a conceptual framework is put forward. Further, determinants of the IL of safety professionals are suggested, including individual attributes, safety climate and culture, information infrastructure, information technology (IT) human resources, production technology and management, and national information policy, law and ethics. Of course, further research on the IL of safety professionals should be carried out for effective SM.  相似文献   
54.
We investigate the stock market response to firm disclosure of positive environmental information and the link from that information to environmental outcomes. We classify environmental media releases by informational content and value relevance, and assess the abnormal stock returns of each type of event. While announcements of future environmental activities lead to the largest favorable stock market reactions, there is no guaranteed link from this type of information to environmental outcomes. Further analysis of the abnormal returns shows that the magnitude of the stock market reaction depends on firm financial characteristics across all event types rather than on firm environmental performance. Our results indicate that the ability for voluntary environmental information disclosure to induce environmental self-regulation is limited to the extent that firms are able to follow through with their announcements of planned environmental activities.  相似文献   
55.
Social network theory has made major contributions to our understanding of human social organisation but has found relatively little application in the field of animal behaviour. In this review, we identify several broad research areas where the networks approach could greatly enhance our understanding of social patterns and processes in animals. The network theory provides a quantitative framework that can be used to characterise social structure both at the level of the individual and the population. These novel quantitative variables may provide a new tool in addressing key questions in behavioural ecology particularly in relation to the evolution of social organisation and the impact of social structure on evolutionary processes. For example, network measures could be used to compare social networks of different species or populations making full use of the comparative approach. However, the networks approach can in principle go beyond identifying structural patterns and also can help with the understanding of processes within animal populations such as disease transmission and information transfer. Finally, understanding the pattern of interactions in the network (i.e. who is connected to whom) can also shed some light on the evolution of behavioural strategies.  相似文献   
56.
Grouping behavior has various types of antipredator functions. Some of these functions require social transmission of information, such as the many-eyes effect, whereas others do not, such as the dilution and confusion effects. Functions of grouping behavior would enhance with social transmission among group members. We investigated and compared the onsets of schooling behavior and social transmission of information in chub mackerel Scomber japonicus. Onset of schooling behavior was observed in rearing tanks by calculating the degree of parallel swimming. Onset of social transmission was examined by using visual cues from conspecifics. A group of five individuals was put in each of three experimental chambers from which they could see a group of conspecifics in the neighboring chamber. A weak electric stimulus was given to one of these chambers, and information transfer among individuals was observed. We found that social transmission by visual cues started on 30 days posthatching (25.1 mm in standard length), which was 2 weeks after the onset of schooling behavior. The late onset of social transmission relative to schooling behavior might be attributed to different predation pressure with development, or by underdevelopment of optic tectum, as the volume of the optic tectum did not increase just after the onset of schooling behavior.  相似文献   
57.
Transfer of information about food source characteristics within insect societies is essential to colony-foraging success. The food odor communicated within honeybee hives has been shown to be important for food source exploitation. When successful foragers return to the nest and transfer the collected nectar to hive mates through mouth-to-mouth contacts (trophallaxis), potential recruits receiving these samples learn the food odor by associative learning. The food then becomes rapidly distributed among colony members, which is mainly a consequence of the numerous trophallaxes between hive-mates of all ages during food processing. We tested whether the distribution of food among hive mates causes a propagation of olfactory information within the hive. Using the proboscis extension response paradigm, we show that large proportions of bees of the age groups representing the main worker castes, 4 to 9-day-old bees (nurse-aged bees), 12 to 16-day-old bees (food processor-aged bees), and actual foragers (about 17+ day old bees) associatively learn the food odor in the course of processing food that has been collected by only a few foragers. Results further suggest that the information is shared more or less equally between bees of the three age groups. This shows that olfactory information about the flower species exploited by foragers is distributed within the entire colony and is acquired by bees of all age groups, which may influence many behaviors inside and outside the hive.  相似文献   
58.
斜坡稳定性的二级模糊推断   总被引:2,自引:0,他引:2  
根据对斜坡稳定性影响的大小,选取了七个主要因于,引用了山西明水河流域几个斜坡样点实测数据.应用模糊近似推论方法及信息分配原理,对斜坡稳定性进行了单因子灰色隶属度分析及综合二级模糊近似推论,该方法克服了传统单因子评价的弊端,能比较真实地反映实际,为布设护坡工程提供了理论依据。  相似文献   
59.
知识经济与环境保护   总被引:1,自引:0,他引:1  
阐述了知识经济的概念及其主要特征,分析了知识经济给环境保护带来的机遇,为迎接知识经济的挑战,上海制定出以发展高技术环保不业和培养高技术环保人才 中心的战略目标,为争2010年在达到申城环境保护第三阶段目标的同时,出现适应知识经济时代 环保新雏型。  相似文献   
60.
电子信息产品的大量生产与使用造成严重的环境污染,影响着人类健康和生态安全。利用生命周期评价技术对电子信息产品的原材料获取、生产、销售运输和使用阶段进行环境影响分析,并得出电子产品在使用阶段的环境影响最为重要。生产商不但要关注生产过程中的环境影响,更应该注重生产低能耗产品。  相似文献   
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