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排序方式: 共有522条查询结果,搜索用时 15 毫秒
281.
灰色马尔柯夫模型在地表水体DO浓度预测中的应用   总被引:10,自引:0,他引:10  
灰色马尔柯夫模型是一种随机预测模型,被广泛的应用于社会,经济的预测中,本文利用灰色马尔柯夫模型对某平原河段DO浓度进行了预测。经验证,灰色马尔柯夫模型适用于对地表水体DO浓度预测,并具有相当高的精度,在此基础上,作者提出了改进的建议,使模型更具有实用性和可操作性。  相似文献   
282.
广州市污水排放分析及预测   总被引:8,自引:0,他引:8  
在分析广州市十几年污水排放特点的基础上,采用灰色理论中的灰色GM(1,1)模型对广州市污水进行建模预测,以便为广州污水处理和规划目标的制定提供宏观依据。  相似文献   
283.
在信息技术飞速发展的今天,地震预报智能决策系统和地震信息系统迫切需要新技术的融入。Web挖掘是目前信息技术中的研究热点,它是现代科学技术相互渗透融合的必然结果。文章首先介绍了Web挖掘的含义,重点讨论了Web文本分类技术,并提出了其在防震减灾辅助决策中的应用模型。  相似文献   
284.
285.
    
As the defining force of the Anthropocene, human enterprise is reshaping Earth's surface and climate. As part of that process, growth-inducing infrastructure, such as electrical transmission lines, export facilities, and roads, presents nonincremental changes in where and how natural resources are exploited. These projects open intact areas, induce or intensify industrial development, and accelerate carbon emissions. The direct impacts of large-scale infrastructure are widely acknowledged and policy and legislation exists to account for them in environmental decisions. Yet, decision makers often ignore the secondary, growth-induced effects, even though they can outweigh the impacts of the initial development. Given the extensive area and magnitude of such impacts, we argue that regulatory or funding approvals for growth-inducing infrastructure represent keystone decisions. Credible approval processes require the consideration of the full range of impacts resulting from the ensuing growth. This will necessitate a shift in assessment thinking, from the traditional focus on the immediate project footprint to one that recognizes the sustainability implications of approving infrastructure that will transform the trajectory of development at regional and national scales. We identify the characteristics of growth-inducing infrastructure and provide an overview of methods and policy that can facilitate a deliberate assessment of these keystone decisions.  相似文献   
286.
    
ABSTRACT. In the past planners have used various approaches to develop alternative plans for planning studies. These include: rational thought which draws upon the planners' knowledge, experience and judgement; objectives which emphasize specific values such as economic and environmental; technologies which achieve the same objective; public preferences which reflect public values and interests; alternative futures which array a diverse range of possible futures; mathematical models which rapidly evaluate possible alternatives; cost sharing policies which consider a participant's financial interest; Delphi technique utilizing a diversity of professional expertise; the IDEA method which stimulates and evaluates large numbers of alternatives. Most of these approaches have found application on various planning studies.  相似文献   
287.
With the growing importance of environmental sustainability in the corporate sector, businesses are compelled to progress from assessing and benchmarking their environmental impact to making decisions on how to prioritize impact reduction alternatives. Most often, business decisions are driven by financial metrics, but with sustainability improvements becoming a business goal, it is also important to assess metrics from environmental and social spheres; nevertheless, practically and systematically performing such an assessment is challenging. We present an application of a multi-criteria decision analysis (MCDA) method that addresses the aforementioned challenges in a corporate setting. Our case study company – one of the largest inland marine freight carriers in the United States – promotes a business culture focused on financially viable, yet socially and environmentally responsible solutions. Thus, we combine life cycle analysis (LCA), financial calculation methods, and corporate surveys to quantify environmental, economic, and social performance measures, respectively. Multiattribute utility theory is integrated with analytic hierarchy processes (AHPs) and fuzzy analysis to create a carefully designed framework for corporations with diverse groups of stakeholders. With company leadership, implementation is feasible and successful at prioritizing alternatives among diverse stakeholders. The process provides a platform for negotiation and promotes discussions on decision drivers. The use of MCDA methodologies promoted the inclusion of a suite of metrics that aligned with the company's sense of social and environmental responsibility, generating an in-depth analysis of the alternatives that factored in other things besides economics. Return-on-investments (ROI) calculations, the typical approach used in the corporate setting, would have required significantly less time and effort from the company, but the results of our MCDA application indicated that inclusion of triple bottom line metrics delve deeper into stakeholder preferences. Thus, our case study company gained a holistic view of the candidate alternatives, in addition to creating a platform for structured discussions about company goals and priorities.  相似文献   
288.
灰色神经网络模型在油气管道腐蚀速度预测中的应用   总被引:8,自引:0,他引:8  
简要说明了GM(1,1)模型和BP神经网络模型预测过程,提出了灰色神经网络组合模型,用此方法对某原油长输管道腐蚀速度进行了预测,并用MatLab语言编程的方法对数据做了处理,结果表明用该方法预测得到的数据与实测值非常接近。  相似文献   
289.
探索了城市空气颗粒物污染控制决策的流程.分析了颗粒物排放源类的分担率、颗粒物的可削减空间、控制措施实施的可执行性及控制技术经济成本等方面对颗粒物污染控制决策的影响,在此基础上,结合空气质量模型、颗粒物来源解析、层次分析法等技术,建立了颗粒物污染控制方案优选方法及相应的决策模型.以天津市为例,分别设定颗粒物各排放源类的控制情景,计算不同控制情景下环境空气中ρ(PM10)削减率,在对所有方案初筛的基础上,采用层次分析法确定颗粒物污染控制的最优方案组合.  相似文献   
290.
从应急物流的定义与特征、系统体系构建、保障机制、风险评估以及定量模型等方面对国内外近10年来的应急物流相关成果进行系统分析,指出当前应急物流存在的问题与不足,探讨应急物流发展趋势.分析表明,国内外对应急物流定量模型的研究主要是选址和调度问题分开进行的,对选址调度问题的集成研究还较少,也没有将应急物流的风险识别与选址调度问题结合起来进行研究.另外,应急物流的开展需要多个部门协同决策,开发应急物流协同决策系统也将是未来的研究方向.  相似文献   
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