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591.
In the field of sustainable product development, a new perspective for approaching sustainability has been advocated, challenging designers and engineers to aim beyond ‘reducing unsustainability’. Several design strategies – including Biomimicry and Cradle to Cradle – have been suggested for developing truly sustainable, or ‘beneficial’, products. But do these strategies help in developing such products, and how to assess their ‘sustainability’? Based on a review of the objectives in nature-inspired design, we argue that assessing environmental sustainability is not straightforward. Whereas both Biomimicry and Cradle to Cradle build on the perspective of ‘achieving sustainability’, current life-cycle assessment-based tools are geared towards reducing current impacts. As a consequence, existing tools are insufficiently equipped for the purpose of the assessment: they do not cover some of the main results that nature-inspired design is set out to accomplish. To be able to include these results, we propose two new constituents to current life-cycle-based product assessment: assessing against conditions of sustainability and assessing ‘achievement’, the extent to which these conditions of sustainability have been achieved. Furthermore, the product context needs to be included for assessing beneficial impacts. This article discusses how these constituents can contribute to an assessment tool that enables designers and engineers to assess the development of environmentally sustainable solutions.  相似文献   
592.
基于以往研究多采用大气数值模式分析污染物在不同城市之间的输送规律及内外源的贡献率,现从时间序列角度引入一个新方法,应用向量自回归模型的格兰杰因果关系检验、脉冲响应函数及方差分解技术,对广州、佛山、肇庆2003-2012年逐日空气污染指数进行模拟演算,得到城市间大气污染相互影响效应及其贡献。结果表明,广佛地区污染源对肇庆空气质量影响突出,肇庆并未成为广州和佛山的主要污染源。城市间大气污染相互影响存在明显的滞后效应,前7期累积作用较明显,污染物的累积效应容易导致区域性灰霾天气出现。佛山对广州的污染贡献达到了10.9%,广州对佛山的污染贡献相对偏小,佛山对肇庆的污染贡献接近30%,广佛肇经济圈应形成区域性大气污染联防联治机制。  相似文献   
593.
Collaborative Modeling for Decision Support integrates collaborative modeling with participatory processes to inform natural resources decisions. Practitioners and advocates claim that the approach will lead to better water management, balancing interests more effectively and reducing the likelihood of costly legal delays. These claims are easy to make, but the benefits will only be realized if the process is conducted effectively. To provide guidance for how to conduct an effective collaborative modeling process, a task committee cosponsored by the Environmental Water Resources Institute (EWRI) of the American Society of Civil Engineers and by the U.S. Army Corps of Engineers' Institute for Water Resources developed a set of Principles and Best Practices for anyone who might convene or conduct collaborative modeling processes. The guidance is intended for both conflict resolution professionals and modelers, and our goal is to integrate these two fields in a way that will improve water resources planning and decision making. Here, the set of eight principles is presented along with a selection of associated best practices, illustrated by two different case examples. The complete document is available at: http://www.computeraideddisputeresolution.us/bestpractices/ .  相似文献   
594.
This article describes the collaborative modeling process and the resulting water resources planning model developed to evaluate water management scenarios in the transboundary Rio Grande basin. The Rio Grande is a severely water stressed basin that faces numerous management challenges as it crosses numerous jurisdictional boundaries. A collaborative process was undertaken to identify and model water management scenarios to improve water supply for stakeholders, the environment, and international obligations of water delivery from Mexico to the United States. A transparent and open process of data collection, model building, and scenario development was completed by a project steering committee composed of university, nongovernmental, and governmental experts from both countries. The outcome of the process was a planning model described in this article, with data and operations that were agreed on by water planning officials in each country. Water management scenarios were created from stakeholder input and were modeled and evaluated for effectiveness with the planning model.  相似文献   
595.
基于差异进化支持向量机的坑外土体沉降预测   总被引:1,自引:0,他引:1  
就用支持向量机(SVM)预测基坑外土体沉降而言,通过差异进化(DE)算法构造适合的决策函数十分重要。在确定坑外土体沉降函数的基本形式下,进行参数反演。后将得到的解析式作为SVM的决策函数,再进行核函数转换,从而使SVM的曲线拟合更加快速,预测更加准确。对大连地铁湾家车站基坑坑外土体的沉降数据的分析及预测的结果表明,使用SVM-DE算法在计算数据量、计算消耗时间和预测精度方面优于2种方法单独使用。  相似文献   
596.
新型带弹簧支撑抗冲击研究及其在泥石流拦挡坝中的应用   总被引:1,自引:0,他引:1  
为了使结构或构件能够更好地承受住泥石流、爆炸等冲击荷载,设计出一种新型带弹簧的支撑(件)。运用显式动力分析方法,对冲击载荷作用下的这种支撑进行数值模拟,计算得到新型支撑的动力响应,并与普通支撑进行对比分析。结果表明,新型支撑能更好地防止冲击荷载作用下的结构过早发生塑性变形。另外,在泥石流防治结构中,引入这种新型支撑,设计出新型泥石流拦挡坝。运用有限元软件ls-dyna对新型泥石流拦挡坝进行大块石冲击模拟,并与普通重力式拦挡坝进行对比分析,得出新型拦挡坝坝底应力远小于普通泥石流拦挡坝的应力。研究结果表明,新型带弹簧支撑及新型泥石流拦挡坝的抗冲击效果非常明显。  相似文献   
597.
The aim of this study was to discover accident factors specific to young workers, using two accident data sets gathered at the same time but with different methods. The first data set consisted of 99 serious occupational accidents, which occured in Southern Finland in 1988 and 1989. The second data set was based on the interview study of over 13,000 people of whom 792 were involved in an accident at work. Both data sets showed consistently that the accident frequency of young workers was higher than that of older workers. The accidents of young workers, however, were less severe. Young accident victims hurt themselves more often when feeding or cleaning machines. Incautiousness contributed more often to accidents of young workers. In order to prevent occupational accidents of young workers, companies should introduce training programmes for new employees.  相似文献   
598.
Environmental assessment of alternative development plans, programs, and policies may bring conflict among decision-makers, particularly when some quantitative measures for decision-making are needed and where cumulative impacts are neglected. Environmental impact assessment (EIA) and environmental economics theories, despite their usefulness, are not capable of addressing those issues and problems alone. In recent years, the decision support system (DSS) has provided some solutions, but mathematical analysis of the system to show the internal structure of the problem is not always possible. To addres the above shortcomings and ongoing problems of decision-making in Iran, a degradation model (DM) was introduced as an instrument of EIA, to act as a DSS for managers. The model is a compromise between knowledge-based decision support systems, detailed models, digested information models, and the basic theorem of environmental economics. In the present study (1996–2000), the model was applied in three provinces of Iran, representing three of four biogeographical regions of Iran. The study area was divided into a set of grids (100 km2). The degradation coefficient (H) was computed for all grids (1333), representing the degree of degradation in the grid. It is obvious that the higher the coefficient the more area is degraded and less prone to further development, and vice versa. In order to provide decision-makers with a set of quantitative measures to observe impacted areas (critical and noncritical) for resource allocation and further development, the degradation coefficients of all grids were classified into categories and criteria, using a fuzzy set theoretic approach. Accordingly, only 24% of study areas are prone to further development. The degradation model as a knowledge-based decision support system has its strengths and weaknesses, but it has solved managers' ongoing problems in Iran and it could be used elsewhere.  相似文献   
599.
事故定性分析与事故定量预测   总被引:2,自引:0,他引:2  
分析了影响事故预测准确的原因,综述了国内外许多学者在事故预测方面所做的努力。指出今后事故预测工作的主要途径是由安全系统工程专家建立计算机支持的决策支持系统(DSS),由安全专家灵活运用这个系统中的计算机辅助研究方法(CAR)。  相似文献   
600.
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