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101.
《International Journal of Sustainable Engineering》2013,6(3):224-235
Reliable prediction of total product life cycle costs is crucial for the life cycle management of products. These costs are predominantly dictated by the actual operational behaviour of the product's lifetime, and cannot be sufficiently determined through deterministic calculations due to the stochastic and the dynamic nature of the problem. This is specifically true when considering running systems with unknown lifetime and operation parameters. Against this background, the paper presents a dynamic methodology for predicting life cycle costs based on product failure mechanisms, their associated critical lifetime prediction parameters and optional maintenance strategies to enable decision support for product design and use phase strategies. 相似文献
102.
Various federal regulations require states to evaluate the effectiveness of their vehicle inspection and maintenance (I/M) programs in reducing in-use emissions. One method to evaluate program effectiveness is to compare initial and final program test results of individual vehicles. Unscheduled emissions measurements, from remote sensing measurement or roadside pullover testing, can also be used to provide an independent assessment of program effectiveness. We compared emissions reductions from the Arizona IM240 program measured by program data and a large set of remote sensing measurements. Remote sensing measurements indicate smaller emission reductions from the program than those calculated directly from program test results. We discuss some possible causes of the differences obtained from the two sets of measurements. 相似文献
103.
出租车排放是城市大气污染的重要来源,对高排放出租车加严管理是改善空气质量的有效手段之一.在北京市选取6辆有代表性的高里程汽油出租车,较全面地评估了维护保养、更换三元催化器对出租车油耗和排放的影响,以及三元催化器在更换后的老化情况.研究表明:常规的维护保养可显著改善车辆的燃油经济性,保养后车辆的100 km油耗比原车降低了2%~4%,但对THC和NOx排放的影响很小.原车排放越高,更换三元催化器的减排效果越显著,且更换第一级三元催化器(前三元催化器)和同时更换第一、二级三元催化器(前、后三元催化器)的减排效果差别较小.更换三元催化器后行驶里程约18.5×104 km时,有4辆出租车对CO、THC和NOx的减排比例仍保持在45%、26%和29%的平均水平,说明更换三元催化器后,在约20×104km的行驶里程内对气态污染物能保持较好的减排效果. 相似文献
104.
研究大型装备备件供应网络面临大规模突发事件时的应急备件调度问题。首先采用信息熵理论对应急维修点进行优先度权重排序;其次建立应急响应时间和需求满意度函数,并将量化后的时间满意度和需求满意度以作为模型的目标函数,构建了网络供应状态下应对突发事件的备件调度规划模型;最后以某大型装备企业备件的应急备件调度为例,验证了模型的有效性,给出调度优化方案。 相似文献
105.
为实现铁路大型养路机械(简称"大机")故障的智能检索和诊断,使用基于案例推理(CBR)的思路分析和设计用以实现这些目的的系统。阐述案例的表示和构建方法。提出捣固车的故障案例模型构建方法。设计捣固车故障诊断的CBR系统。给出带权值的k-近邻法的案例相似性检索方法。提出大机故障诊断智能决策系统,采用定性和定量检索相结合的方法。故障诊断系统能够进行案例的定性、定量和混合检索。用捣固车的具体故障案例,验证所设计的系统的可行性。诊断系统检索得到的故障类型与依据现场采集的数据判定的故障类型基本一致,能够进行案例调用和修改。 相似文献
106.
107.
本文主要介绍国家标准GB/T 29512—2013的实施背景以及防护手套的选择、使用和维护指南,并提出标准实施的建议。 相似文献
108.
膜生物反应器无剩余污泥排放的研究 总被引:42,自引:2,他引:40
本文介绍了以膜生物反应器为基础的剩余污泥产量最少或无剩余污泥产生的最新的污水处理理论和技术。从技术微生物基本生命活动的物质转化概念和细胞产生和平衡的理论,提出了确定维持微生物基本生命活动的物质转化系数的方法,从理论与实验上计实了膜生物反应器无剩余污泥排放的可能性。 相似文献
109.
110.
The potential to capture carbon from industrial sources and dispose of it for the long-term, known as carbon capture and sequestration (CCS), is widely recognized as an important option to reduce atmospheric carbon dioxide emissions. Specifically, CCS has the potential to provide emissions cuts sufficient to stabilize greenhouse gas levels, while still allowing for the continued use of fossil fuels. In addition, CCS is both technologically-feasible and commercially viable compared with alternatives with the same emissions profile. Although the concept appears to be solid from a technical perspective, initial public perceptions of the technology are uncertain. Moreover, little attention has been paid to developing an understanding of the social and political institutional infrastructure necessary to implement CCS projects. In this paper we explore a particularly dicey issue--how to ensure adequate long-term monitoring and maintenance of the carbon sequestration sites. Bonding mechanisms have been suggested as a potential mechanism to reduce these problems (where bonding refers to financial instruments used to ensure regulatory or contractual commitments). Such mechanisms have been successfully applied in a number of settings (e.g., to ensure court appearances, completion of construction projects, and payment of taxes). The paper examines the use of bonding to address environmental problems and looks at its possible application to nascent CCS projects. We also present evidence on the use of bonding for other projects involving deep underground injection of materials for the purpose of long-term storage or disposal. 相似文献