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621.
基于GIS的铁路行车事故救援系统研究 总被引:5,自引:1,他引:4
笔者扼要探讨了构建基于GIS的铁路行车事故救援系统的相关理论和方法 ,提出了该系统的设计目标、功能结构、体系结构以及空间数据库设计的简要准则和空间数据的输入方法。笔者还介绍了结合实际科研项目 ,开发的大秦线事故救援辅助决策支持系统。该系统具有以下几方面的特点 :在以工务信息为主体的基础上 ,实现了车、机、工、电、辆各部门主要业务信息以及事故救援预案信息的初步整合 ;实现了线路录像按里程点播以及录像与线路设备综合图的联动 ;实现了事故救援的辅助决策支持 ,提供了一个可以扩展的理想平台。 相似文献
622.
Decision Support for Road System Analysis and Modification on the Tahoe National Forest 总被引:1,自引:0,他引:1
The United States Forest Service is required to analyze road systems on each of the national forests for potential environmental impacts. We have developed a novel and inexpensive way to do this using the Ecosystem Management Decision Support program (EMDS). We used EMDS to integrate a user-developed fuzzy logic knowledge base with a grid-based geographic information system to evaluate the degree of truth for assertions about a roads environmental impact. Using spatial data for natural and human processes in the Tahoc National Forest (TNF, California, USA), we evaluated the assertion the road has a high potential for impacting the environment. We found a high level of agreement between the products of this evaluation and ground observations of a TNF transportation engineer, as well as occurrences of road failures. We used the modeled potential environmental impact to negatively weight roads for a least-cost path network analysis to 1573 points of interest in the forest. The network analysis showed that out of 8233 km of road analyzed in the forest, 3483 km (42%) must be kept in a modified road network to ensure access to these points. We found that the modified network had improved patch characteristics, such as significantly fewer cherry stem roads intruding into patches, an improved area-weighted mean shape index, and larger mean patch sizes, as compared to the original network. This analysis system could be used by any public agency to analyze infrastructure for environmental or other risk and included in other mandated analyses such as risks to watersheds. 相似文献
623.
Decision Support System for Managing Oil Spill Events 总被引:3,自引:0,他引:3
The Mediterranean environment is exposed to various hazards, including oil spills, forest fires, and floods, making the development of a decision support system (DSS) for emergency management an objective of utmost importance. The present work presents a complete DSS for managing marine pollution events caused by oil spills. The system provides all the necessary tools for early detection of oil-spills from satellite images, monitoring of their evolution, estimation of the accident consequences and provision of support to responsible Public Authorities during clean-up operations. The heart of the system is an image processing–geographic information system and other assistant individual software tools that perform oil spill evolution simulation and all other necessary numerical calculations as well as cartographic and reporting tasks related to a specific management of the oil spill event. The cartographic information is derived from the extant general maps representing detailed information concerning several regional environmental and land-cover characteristics as well as financial activities of the application area. Early notification of the authorities with up-to-date accurate information on the position and evolution of the oil spill, combined with the detailed coastal maps, is of paramount importance for emergency assessment and effective clean-up operations that would prevent environmental hazard. An application was developed for the Region of Crete, an area particularly vulnerable to oil spills due to its location, ecological characteristics, and local economic activities. 相似文献
624.
Degradation Model: A Quantitative EIA Instrument,Acting as a Decision Support System (DSS) for Environmental Management 总被引:1,自引:0,他引:1
Makhdoum MF 《Environmental management》2002,30(1):151-156
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
625.
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
626.
Daniel P. Loucks 《Journal of the American Water Resources Association》1995,31(4):571-582
ABSTRACT: Computer-based models together with their interactive interfaces are typically called decision support systems. DSSs are interactive computer-based information providers. The common objective of all DSSs, regardless of the frameworks, methodologies, or techniques used, is to provide timely information that supports human decision makers - at whatever level of decision making. The informational needs of the decision making process are the key considerations that motivate the development of DSSs. The growth of DSS development and use has been substantial. In spite of this impressive growth, computer-aided decision support systems can still be improved and made more useful to those they are intended to support. Researchers and practitioners, and indeed the computer industry, continue to identify ways of doing this. This paper reviews some of these needs and opportunities by focusing on the process of successful DDS development and implementation. The paper outlines an approach and some guidelines for developing DSSs. The approach emphasizes and requires considerable interaction between the DSS developers (analysts) and the DSS users (decision makers). This interaction and feedback is required throughout the entire DSS building, testing and evaluation (debugging), and implementation processes. The paper concludes by identifying some research needs and opportunities affecting DSS development and effective use. 相似文献
627.
Kenneth H. Reckhow 《Environmental management》1994,18(2):161-166
Uncertainty in environmental decision making should not be thought of as a problem that is best ignored. In fact, as is illustrated
in a simple example, we often informally make use of awareness of uncertainty by hedging decisions away from large losses.
This hedging can be made explicit and formalized using the methods of decision analysis. While scientific uncertainty is undesirable,
it can still be useful in environmental management as it provides a basis for the need to fund additional monitoring, experimentation,
or information acquisition to improve the scientific basis for decisions. 相似文献
628.
A broad and objective perspective of ecological and socioenomic knowledge is required to underlie a scientific approach to
the problems of terrestrial restoration ecology. Uncertainty associated with limited scientific knowledge highlights the crucial
importance of the interaction between science and policy in weighing ecological restoration alternatives in relation to other
management options. In this paper, we provide a pragmatic definition for restoration ecology that is suitable for extensive
terrestrial applications and present a decision framework to help organize and clarify different phases of the decision process
as it is related to ecological restoration. We argue that restoration planning should include a wider spectrum of participants
and decisions than have traditionally been employed. 相似文献
629.
矿山企业安全管理决策支持系统的智能化 总被引:1,自引:0,他引:1
矿山安全工程技术人员需要开发使数学模型和安全信息便于操作的软件环境,并与人工智能技术集成一体。本文所介绍的矿山企业安全管理智能化决策支持系统SMDSS,是专家系统与决策支持系统两者的集成。SMDSS可用于企业安全评价、事故统计分析与查询、事故动态预测与预报、FTA的计算、安全措施计划的编制、安全投资的最优分配。 相似文献
630.
William J. Petak 《Environmental management》1981,5(3):213-224
This paper presents a system framework whose purpose is to improve understanding of environmental management. By analyzing the links between elements of the environmental management system, it is possible to construct a model that aids thinking systematically about the decision-making subsystem, and other subsystems, of the entire environmental management system.Through a multidisciplinary environmental approach, each of the individual subsystems is able to adapt to threats and opportunities. The fields of government, market economics, social responsibility and ecology, for example, are so complex that it is extremely difficult to develop a framework that gives full consideration to all aspects. This paper, through the application of a highly idealized system framework, attempts to show the general relationships that exist between complex system elements. 相似文献