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351.
352.
基于Multi-agent的矿工情绪稳定性模型构建   总被引:1,自引:0,他引:1  
为解决由矿工情绪稳定性水平低下引起的不安全行为问题,基于复杂适应系统(CAS)理论和多主体建模与仿真(ABMS)的方法,构建矿工情绪稳定性水平提升模型。通过调节班组协调程度、组织公平程度、安全心理培训水平、受教育程度、个性特征和作业环境舒适度,在NETLOGO仿真平台上分析矿工意志强度、情绪安全倾向度以及管理者领导能力对矿工情绪稳定性水平的影响。研究表明:矿工的情绪稳定性水平提升系统是一种典型的复杂适应系统,矿工情绪稳定性水平是各主体属性相互作用的结果,作用程度存在差异。因此,煤炭企业应考虑各种因素,通过控制和改善各主体的行为以提高矿工情绪稳定性水平。  相似文献   
353.
《Environmental Hazards》2013,12(4):267-280
The present perspective summarizes and projects the results of a two-day workshop held in 2013 with the presence of 21 known disaster risk specialists from academia and practice. Faced with the disconnect between ever-increasing and even-accelerating disaster losses and the declared progress in disaster risk management (DRM) practice over the last eight years, the document attempts to explain the current situation and project future needs in order to increase the saliency and effect of DRM. A review of current conceptual problems and their impact on knowledge and action, of the current role of DRM in society, of governance aspects and of the notion of transformative development and its relationship to DRM is provided. The critique of current practice and understanding of disaster risk then leads to an attempt to identify key needs for the future and changes that must be introduced in order for DRM to become more mainstream and effective. Among the more central concerns, the document points to the way in which disasters are still many times seen as exogenous happenings as opposed to social constructions, product of skewed development practices. This then is reflected in much governance practice and action that are flawed. The difficulty in moving from a reactive and corrective DRM practice to a more prospective, risk avoidance practice is also highlighted.  相似文献   
354.
Populations affected by violent conflicts often withstand threats to their security as well as threats to their livelihoods. Their response to the former threats nontrivially affects their response to the latter threats, and vice versa. This paper examines the interplay between protection and livelihood strategies using a sample of households selected from the Anuradhapura district of Sri Lanka. The fieldwork for this study was completed in 2008, producing evidence that the protection and livelihood strategies employed by households affected by the protracted conflict in Sri Lanka are interlaced. In addition, the research discovered that Muslim and Sinhalese households largely responded to the protracted conflict in ways that are unique to their ethnic group. Certain vulnerabilities that impinge on protection and certain opportunities that support livelihoods are shown to be ethnicised. Hence, the final livelihood outcome, which is defined narrowly here as the household's income, also appears to be ethnicised.  相似文献   
355.
Abstract: The National Research Council recommended Adaptive Total Maximum Daily Load implementation with the recognition that the predictive uncertainty of water quality models can be high. Quantifying predictive uncertainty provides important information for model selection and decision‐making. We review five methods that have been used with water quality models to evaluate model parameter and predictive uncertainty. These methods (1) Regionalized Sensitivity Analysis, (2) Generalized Likelihood Uncertainty Estimation, (3) Bayesian Monte Carlo, (4) Importance Sampling, and (5) Markov Chain Monte Carlo (MCMC) are based on similar concepts; their development over time was facilitated by the increasing availability of fast, cheap computers. Using a Streeter‐Phelps model as an example we show that, applied consistently, these methods give compatible results. Thus, all of these methods can, in principle, provide useful sets of parameter values that can be used to evaluate model predictive uncertainty, though, in practice, some are quickly limited by the “curse of dimensionality” or may have difficulty evaluating irregularly shaped parameter spaces. Adaptive implementation invites model updating, as new data become available reflecting water‐body responses to pollutant load reductions, and a Bayesian approach using MCMC is particularly handy for that task.  相似文献   
356.
不同覆土厚度的煤矸石充填复垦区土壤生产力评价   总被引:7,自引:0,他引:7  
以淮南矿区新庄孜煤矿采煤塌陷区土地复垦区为研究对象,调查了不同覆土厚度的煤矸石充填复垦区土壤生产力状况,发现在以煤矸石充填为基底,上覆不同表土厚度的区域土壤生产能力差异较大,其中覆土较厚的地块小麦产量达到5 770 kg/hm2,覆土较薄的地块只有4 736 kg/hm2。运用了复垦土壤生产力指数的修正模型(MPI)对不同覆土厚度的复垦地块生产力进行评价。结果表明,覆土75 cm和90 cm的地块的水解性氮和速效钾的适应性接近于对照地块,速效磷和有机质的适应性稍微偏低,生产力水平接近于对照地块;覆土40 cm和60 cm的地块土壤的养分普遍偏低,限制了农作物的生长;通过对评价结果的误差分析显示,本次评价的最小误差为1.65%,最大误差为4.33%,运用MPI模型对煤矸石复垦土壤生产力的评价具有较高的精确度。  相似文献   
357.
利用江西省36县346个农户调查数据,运用Heckman Probit选择模型实证分析了影响农户气候变化感知及其适应行为决策的因素,结果表明,户主年龄、文化程度、与村民交流频率、来往亲戚数、赶集频率、看电视频率、距离市场远近及气象信息服务等因素能显著影响农户对气候变化的感知;而户主性别、年龄、文化程度、可借款人数、来往亲戚数、赶集频率、看电视频率及气象信息服务等因素对农户气候变化适应行为决策有显著影响。最后,根据实证分析结果,提出了促进农户采用气候变化适应行为的政策建议。  相似文献   
358.
青藏高原的放牧系统具有重要的生态和生计意义,但目前正受到气候变化和人为干扰的双重威胁。为寻找改善现状的着力点,有必要探究青藏高原放牧系统的现状与演变趋势。以青藏高原东北部的共和县为例,基于历史统计数据、地方志与文献资料,在社会—生态系统的视角下,运用描述系统演变的扰沌模型,分析共和县放牧社会—生态系统的历史变迁、现状以及未来发展趋势。其中与经济相关的家庭生计—市场子系统目前处于平稳积累资源阶段,与生态相关的草—畜子系统处于释放阶段的早期,社会子系统处于偏离正常轨迹的重组阶段。草—畜子系统的情况恶化并将为更大时空尺度的社会子系统带来负面影响。未来要注意防止家庭畜牧生产与畜牧业市场的过度连接,维护畜牧产业链上的获益公平,提升牧民收入来源多样化程度;注重草地治理,提升基层监理队伍的数量和质量,鼓励合作社优化畜群结构从而与草地匹配,制定合理的政策帮助牧民社会适应外来变化。  相似文献   
359.
Soil salinization is a potentially negative side effect of irrigation with reclaimed water. While optimization schemes have been applied to soil salinity control, these have typically failed to take advantage of real-time sensor feedback. This study incorporates current soil observation technologies into the optimal feedback-control scheme known as Receding Horizon Control (RHC) to enable successful autonomous control of soil salinization. RHC uses real-time sensor measurements, physically-based state prediction models, and optimization algorithms to drive field conditions to a desired environmental state by manipulating application rate or irrigation duration/frequency. A simulation model including the Richards equation coupled to energy and solute transport equations is employed as a state estimator. Vertical multi-sensor arrays installed in the soil provide initial conditions and continuous feedback to the control scheme. An optimization algorithm determines the optimal irrigation rate or frequency subject to imposed constraints protective of soil salinization. A small-scale field test demonstrates that the RHC scheme is capable of autonomously maintaining specified salt levels at a prescribed soil depth. This finding suggests that, given an adequately structured and trained simulation model, sensor networks, and optimization algorithms can be integrated using RHC to autonomously achieve water reuse and agricultural objectives while managing soil salinization.  相似文献   
360.
A greater understanding of gendered roles in fisheries is necessary to value the often-hidden roles that women play in fisheries and households. We examine women’s contributions to household food and income using focus group discussions, market surveys, and landings data in six communities in Timor-Leste. Women were actively fishing more days per month than men. Gleaning was the most frequent activity and 100% of trips returned with catch for food and/or income. Mollusc and crab catches were common and exploitation appeared targeted on a dynamic reappraisal of changing food values and changing estimates of group needs. With as many as 80% of households in coastal areas involved in fishing, and at least 50% of women fishing, this highlights the current lack of women’s engagement as a critical gap in fisheries management approaches. The current androcentric dialogue limits social-ecological understanding of these systems and the potential for their effective stewardship.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01335-7) contains supplementary material, which is available to authorized users.  相似文献   
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