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971.
Permit-trading policy in a total maximum daily load (TMDL) program may provide an additional avenue to produce environmental benefit, which closely approximates what would be achieved through a command and control approach, with relatively lower costs. One of the important considerations that might affect the effective trading mechanism is to determine the dynamic transaction prices and trading ratios in response to seasonal changes of assimilative capacity in the river. Advanced studies associated with multi-temporal spatially varied trading ratios among point sources to manage water pollution hold considerable potential for industries and policy makers alike. This paper aims to present an integrated simulation and optimization analysis for generating spatially varied trading ratios and evaluating seasonal transaction prices accordingly. It is designed to configure a permit-trading structure basin-wide and provide decision makers with a wealth of cost-effective, technology-oriented, risk-informed, and community-based management strategies. The case study, seamlessly integrating a QUAL2E simulation model with an optimal waste load allocation (WLA) scheme in a designated TMDL study area, helps understand the complexity of varying environmental resources values over space and time. The pollutants of concern in this region, which are eligible for trading, mainly include both biochemical oxygen demand (BOD) and ammonia-nitrogen (NH3-N). The problem solution, as a consequence, suggests an array of waste load reduction targets in a well-defined WLA scheme and exhibits a dynamic permit-trading framework among different sub-watersheds in the study area. Research findings gained in this paper may extend to any transferable dynamic-discharge permit (TDDP) program worldwide.  相似文献   
972.
973.
Test case based risk predictions using artificial neural network   总被引:3,自引:0,他引:3  
INTRODUCTION: The traditional fuzzy-rule-based risk assessment technique has been applied in many industries due to the capability of combining different parameters to obtain an overall risk. However, a drawback occurs as the technique is applied in circumstances where there are multiple parameters to be evaluated that are described by multiple linguistic terms. METHOD: In this study, a risk prediction model incorporating fuzzy set theory and Artificial Neural Network (ANN) capable of resolving the problem encountered is proposed. An algorithm capable of converting the risk-related parameters and the overall risk level from the fuzzy property to the crisp-valued attribute is also developed. Its application is demonstrated by a test case evaluating the navigational safety within port areas. RESULTS: It is concluded that a risk predicting ANN model is capable of generating reliable results as long as the training data takes into account any potential circumstance that may be met. IMPACT ON INDUSTRY: This paper provides safety assessment practitioners with a novel and flexible framework of modelling risks using a fuzzy-rule-base technique. It is especially applicable in circumstances where there are multiple parameters to be considered. The proposed framework also enables the port industry to manage navigational safety in a rational manner.  相似文献   
974.
基于混沌理论的企业危机管理研究   总被引:8,自引:3,他引:5  
企业的有效运行和发展历程中都不可避免会面临不同程度的危机,揭示其危机成因,回避危机、化解风险十分重要。企业危机是一个复杂的非线性的能量耗散系统,具有类似混沌的本质特征。笔者运用混沌理论,从“消极、失误、弊病”角度研究企业危机现象,着重探讨企业危机的混沌特征及其发生动因,并提出危机的混沌理论管理原则。针对企业实际,给出控制危机混沌发生,改变危机系统的动态行为,以化解或转化危机的5种对策及方法,实现企业可持续发展。  相似文献   
975.
矿井瓦斯涌出量预测的GM(1,1)模型研究   总被引:6,自引:0,他引:6  
矿井瓦斯渗出量预测,对矿井安全及正常生产至关重要。由于矿井瓦斯涌出量的影响因索、关联变量和约束条件复杂,对各因素之间的影响程度难以区分和把握,因此在预测预报中的精度较差。而采用灰色理论则具有高度的概括性,可以把各种不确定的因素,统一用一个简单的“灰数”表示,预测精度高而且使用简单。在分析某矿历年来相对瓦斯涌出量的基础上,应用灰色系统理论对其瓦斯涌出量进行了预测,其方法与结果对预防煤矿恶性事故的发生,悍证煤矿的安全生产具有重要意义。  相似文献   
976.
针对特种设备数量和种类不断增多与安全监管力量不足问题,首先阐述特种设备安全监管内涵,分析其涉及的委托代理关系;然后基于委托代理理论构建特种设备安全监管委托代理数学模型,并利用激励相容约束条件讨论监管力度、安全投入、公众信任度等因素对特种设备安全监管效果的影响及内在机制;最后提出进一步提高特种设备安全水平的改进策略.结果...  相似文献   
977.
为了探讨大气气溶胶的吸湿性特征,基于观测气溶胶化学组分,计算了吸湿性参数κ.首先,通过PCA分析法,得到了对吸湿性参数κ贡献率较大的化学因子;其次,基于K?hler公式与ZSR混合理论,对各化学组分加权得到各时刻对应的吸湿性参数κchemical;最后,基于κ-K?hler理论,讨论κchemical与其相关性,并通过...  相似文献   
978.
在对国内外该领域研究现状进行分析的基础上,提出了我国目前需要研究的主要问题、研究的基本思路和方法以及研究的重点和难点。将国外先进的理论和方法与我国消防监督管理的实践相结合,探索一条适合中国国情的消防管理模式。为完善我国消防与保险方面的相关技术与法规提供了建议,对完善我国消防监督管理的体制、充分发挥火灾保险的重要作用以及调动全社会参与消防的积极性等方面提供了重要的决策依据。  相似文献   
979.
Annually, in Australia, 10-15% of all road-related fatalities involve pedestrians. Of those pedestrians fatally injured, approximately 45% were walking while intoxicated or ‘drink walking’. Drink walking is increasing in prevalence and younger persons may be especially prone to engage in this behaviour and, thus, are at heightened risk of being injured or killed. Presently, limited research is available regarding the factors which influence individuals to drink walk. This study explored young people’s (17-25 years) intentions to drink walk, using an extended Theory of Planned Behaviour (TPB). Participants (N = 215), completed a self-report questionnaire which assessed the standard TPB constructs (attitude, subjective norm, perceived behavioural control) as well as the extended constructs of risk perception, anticipated regret, and past behaviour. It was hypothesised that the standard TPB constructs would significantly predict individuals’ reported intentions to drink walk and that the additional constructs would predict intentions over and above the TPB constructs. The TPB variables significantly predicted 63.2% of the variance in individuals’ reported intentions to drink walk, and the additional variables, combined, explained a further 6.1% of the variance. Of the additional constructs, anticipated regret and past behaviour, but not risk perception, were significant predictors of drink walking intentions. As one of the first studies to provide a theoretically-based investigation of factors influencing individuals’ drink walking intentions, the current study’s findings have potentially significant implications for understanding young people’s decisions to drink walk and the design of future countermeasures to ultimately reduce this behaviour.  相似文献   
980.
基于图论的海洋平台连锁风险评价   总被引:1,自引:1,他引:0  
为控制海洋平台连锁风险,基于图论(GT),提出一种新型定性风险评价方法,将分析对象的复杂风险分析转化为图形分析运算。该方法综合考虑研究对象的风险,重点考虑事故可能的发展模式,建立并转换可能发生的事故的连锁图,用图论算法进行图形运算,得到造成结果事故发生的关键路径、最短路径和点割集,设置并优化安全屏障,防止初始事故发生。最后,结合墨西哥湾事故,建立事故连锁图,通过图形变换与运算得到2条最短路径、3条关键路径和2个点割集,并提出风险控制措施。  相似文献   
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