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81.
Introduction: Technological advancements during recent decades have led to the development of a wide array of tools and methods in order to record driving behavior and measure various aspects of driving performance. The aim of the present study is to present and comparatively assess the various driver recording tools that researchers have at their disposal. Method: In order to achieve this aim, a multitude of published studies from the international literature have been examined based on the driver recording methodologies that have been implemented. An examination of more traditional survey methods (questionnaires, police reports, and direct observer methods) is initially conducted, followed by investigating issues pertinent to the use of driving simulators. Afterwards, an extensive section is provided for naturalistic driving data tools, including the utilization of on-board diagnostics (OBD) and in-vehicle data recorders (IVDRs). Lastly, in-depth incident analysis and the exploitation of smartphone data are discussed. Results: A critical synthesis of the results is conducted, providing the advantages and disadvantages of utilizing each tool and including additional knowledge regarding ease of experimental implementation, data handling issues, impacts on subsequent analyses, as well as the respective cost parameters. Conclusions: New technologies provide undeniably powerful tools that allow for seamless data handling, storage, and analysis, such as smartphones and in-vehicle data recorders. However, this sometimes comes at considerable costs (which may or may not pay off at a later stage), while legacy driver recording methods still have their own niches to fill in research. Practical Applications: The present research supports researchers when designing driver behavior monitoring studies. The present work enables better scheduling and pacing of research activities, but can also provide insights for the distribution of research funds. 相似文献
82.
83.
为进一步探索数据挖据技术在组织事故预防工作中的融入性与适用性,基于24Model构建事故预控基础模型,通过预测准确率数值及接受者操作特性曲线(ROC曲线)对比分析随机森林(RF)、支持向量机(SVM)、决策树(DT)与神经网络(NN)4种方法对组织事故防控效果的预测性能。结果表明:针对事故率控制(Y1)、职业危害预防(Y2)、财产损失3类预测目标(Y3),RF方法均能达到较高的准确率及稳定性,具有较优的预测性能。根据特征重要度(FI)排序,明确对组织事故水平影响最显著的因素为安全实践活动认知(SC5)及安全管理程序文件(SMS3),FI值均大于0.150 0。研究结果可为有效预测组织事故防控效果提供方法依据,同时为企业安全工作的规划设计提供思路。 相似文献
84.
伴随经济发展的迅速,人们对环境越来越重视,国家也制定了相应的环境执法与保护措施,保障环境质量。在环境执法的过程中,必须严格依照环境监测的数据,从而保障信息的准确性,使环境执法策略的开展能够顺应时代发展,符合目前发展的现状。因此,环境执法中环境监测数据占据重要的位置。基于此,本文分析了环境执法中环境监测数据的应用,笔者根据自身经验提出相应的建议。 相似文献
85.
本文首先分析了生态环境信息化体系的主要构成要素,其后基于大数据技术的生态环境信息化体系重点领域应用进行了深入研究。 相似文献
86.
Nicole F. Opalinski Aditi S. Bhaskar Dale T. Manning 《Journal of the American Water Resources Association》2020,56(1):68-81
Weather variability has the potential to influence municipal water use, particularly in dry regions such as the western United States (U.S.). Outdoor water use can account for more than half of annual household water use and may be particularly responsive to weather, but little is known about how the expected magnitude of these responses varies across the U.S. This nationwide study identified the response of municipal water use to monthly weather (i.e., temperature, precipitation, evapotranspiration [ET]) using monthly water deliveries for 229 cities in the contiguous U.S. Using city‐specific multiple regression and region‐specific models with city fixed effects, we investigated what portion of the variability in municipal water use was explained by weather across cities, and also estimated responses to weather across seasons and climate regions. Our findings indicated municipal water use was generally well‐explained by weather, with median adjusted R2 ranging from 63% to 95% across climate regions. Weather was more predictive of water use in dry climates compared to wet, and temperature had more explanatory power than precipitation or ET. In response to a 1°C increase in monthly maximum temperature, municipal water use was shown to increase by 3.2% and 3.9% in dry cities in winter and summer, respectively, with smaller changes in wet cities. Quantifying these responses allows urban water managers to plan for weather‐driven variability in water use. 相似文献
87.
Andrew S. Jones Allan A. Andales Jos L. Chvez Cullen McGovern Garvey E.B. Smith Olaf David Steven J. Fletcher 《Journal of the American Water Resources Association》2020,56(2):201-211
We apply predictive weather metrics and land model sensitivities to improve the Colorado State University Water Irrigation Scheduler for Efficient Application (WISE). WISE is an irrigation decision aid that integrates environmental and user information for optimizing water use. Rainfall forecasts and verification performance metrics are used to estimate predictive rainfall probabilities that are used as input data within the irrigation decision aid. These input data errors are also used within a land model sensitivity study to diagnose important prognostic water movement behaviors for irrigation tool development purposes simultaneously performing the analysis in space and time. Thus, important questions such as “how long can a crop water application be delayed while maintaining crop yield production?” are addressed by evaluating crop growth stage interactions as a function of soil depth (i.e., space), rainfall events (i.e., time), and their probabilistic uncertainties. Editor’s note : This paper is part of the featured series on Optimizing Ogallala Aquifer Water Use to Sustain Food Systems. See the February 2019 issue for the introduction and background to the series. 相似文献
88.
Kumar PR 《Environmental monitoring and assessment》2006,117(1-3):215-233
In this paper, an attempt has been made to highlight an experimental methodology for monitoring contaminant transport through
locally available silty soil and commercially available clay in geotechnical centrifuge models, for different compaction states.
Use of multiple depth sensors to determine depth distribution of sodium chloride in the soil column has been detailed. The
obtained results have been compared with argentometric method. To validate the centrifuge modelling, modelling of models has
been used. The test setup developed can simulate contaminant transport mechanisms through the soil mass, which is approximately
10 m deep, over a period of 600 days. R
e and P
e are found to be N times higher in the centrifuge models. These numbers are found to be several orders less than unity. This indicates that
laminar flow prevails and the dominating Cl− transport mechanism in centrifuge is diffusion. The study also highlights the fact that the geotechnical centrifuge modelling
can be used as a viable alternative to field scale experimentation. 相似文献
89.
Weyer PJ Smith BJ Feng ZF Kantamneni JR Riley DG 《Environmental monitoring and assessment》2006,116(1-3):81-90
Nitrate contamination of water sources is a concern where large amounts of nitrogen fertilizers are regularly applied to soils.
Ingested nitrate from dietary sources and drinking water can be converted to nitrite and ultimately to N-nitroso compounds,
many of which are known carcinogens. Epidemiologic studies of drinking water nitrate and cancer report mixed findings; a criticism
is the use of nitrate concentrations from retrospective drinking water data to assign exposure levels. Residential point-of-use
nitrate data are scarce; gaps in historical data for municipal supply finished water hamper exposure classification efforts.
We used generalized linear regression models to estimate and compare historical raw water and finished water nitrate levels
(1960s--1990s) in single source Iowa municipal supplies to determine whether raw water monitoring data could supplement finished
water data to improve exposure assessment. Comparison of raw water and finished water samples (same sampling date) showed
a significant difference in nitrate levels in municipalities using rivers; municipalities using other surface water or alluvial
groundwater had no difference in nitrate levels. A regional aggregation of alluvial groundwater municipalities was constructed
based on results from a previous study showing regional differences in nitrate contamination of private wells; results from
this analysis were mixed, dependent upon region and decade. These analyses demonstrate using historical raw water nitrate
monitoring data to supplement finished water data for exposure assessment is appropriate for individual Iowa municipal supplies
using alluvial groundwater, lakes or reservoirs. Using alluvial raw water data on a regional basis is dependent on region
and decade. 相似文献
90.
This work represents an attempt to define a simple method to classify the relative degree of disturbance of sites in lotic
systems on the basis of comparison of their faunistic composition with reference sites. Two ecotypes were selected in northern
Portugal where benthic invertebrates were sampled in reaches with different levels of contamination. As a first stage, previous
Geographic Information System information was used to define reference sites in each ecotype. Afterwards, multivariate techniques
and non linear estimation models were combined to assess biological quality. This method allowed us to quantify sites according
to increasing levels of contamination, after the probabilities of occurrence of taxa along a gradient of contamination taking
into account the reference condition. The results suggest that this method is sensitive to organic pollution, easy to interpret,
namely the species tolerance, and could be a good framework to establish regional rankings depending on the ecological impact
of river sites. 相似文献