全文获取类型
收费全文 | 35篇 |
免费 | 0篇 |
国内免费 | 1篇 |
专业分类
安全科学 | 10篇 |
环保管理 | 5篇 |
综合类 | 13篇 |
基础理论 | 2篇 |
污染及防治 | 2篇 |
评价与监测 | 3篇 |
灾害及防治 | 1篇 |
出版年
2023年 | 1篇 |
2021年 | 3篇 |
2019年 | 1篇 |
2017年 | 2篇 |
2016年 | 1篇 |
2014年 | 2篇 |
2013年 | 3篇 |
2012年 | 1篇 |
2009年 | 1篇 |
2007年 | 4篇 |
2006年 | 1篇 |
2005年 | 2篇 |
2004年 | 4篇 |
2003年 | 1篇 |
2000年 | 1篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1996年 | 1篇 |
1994年 | 1篇 |
1992年 | 1篇 |
1986年 | 1篇 |
1982年 | 1篇 |
1981年 | 1篇 |
排序方式: 共有36条查询结果,搜索用时 93 毫秒
21.
A review of criteria for evaluating natural areas 总被引:12,自引:0,他引:12
Environmental Management - Methods for evaluating natural areas have evolved in the last couple of decades to assess the importance of natural areas for the purposes of land-use planning,... 相似文献
22.
Introduction: Speed cameras have been implemented to improve road safety over recent decades in the UK. Although the safety impacts of the speed camera have been estimated thoroughly, the criteria for selecting camera sites have rarely been studied. This paper evaluates the current speed camera sites selection criteria in the UK based on safety performance. Method: A total of 332 speed cameras and 2,513 control sites with road traffic accident data are observed from 2002 to 2010. Propensity score matching method and empirical Bayes method are employed and compared to estimate the safety effects of speed cameras under different scenarios. Results: First, the main characteristics of speed cameras meeting and not meeting the selection criteria are identified. The results indicate that the proximity to school zones and residential neighborhoods, as well as population density, are the main considerations when selecting speed camera sites. Then the official criteria used for selecting camera sites are evaluated, including site length (a stretch of road that has a fixed speed camera or has had one in the past), previous accident history, and risk value (a numerical scale of the risk level). The results suggest that a site length of 500 m should be used to achieve the optimum safety effects of speed cameras. Furthermore, speed cameras are most effective in reducing crashes when the requirement of minimum number of historical killed and seriously injured collisions (KSIs) is met. In terms of the risk value, it is found that the speed cameras can obtain optimal effectiveness with a risk value greater than or equal to 30, rather than the recommended risk value of 22. 相似文献
23.
Management of safety, and barriers in particular, includes using information expressing performance, i.e. use of safety performance indicators. For this information to be useful, the indicators should demonstrate adequate quality. In other words, they should satisfy some predefined set of quality criteria. Without showing adequate quality, the indicators are generally unable to provide sufficient support for barrier management, which could result in poor decisions. In this article, the use of the SMART criteria is considered to assess the quality of safety performance indicators in process industries. SMART being an acronym for ‘specificity’, ‘measurability’ or ‘manageability’, ‘achievability’, ‘relevancy’ and ‘time-based’, covering five key aspects and criteria for assessing the quality of an indicator. A discussion on whether the indicators are able to demonstrate adequate quality by satisfying these criteria has been conducted. The finding is that all of the SMART criteria should be satisfied for a safety performance indicator to demonstrate acceptable quality and to be regarded as useful to support barrier management decision-making. However, it has also been observed that including the ‘M’ criterion in the assessment of quality is not needed. When all the other criteria are satisfied there is no way the conclusions could be misleading as a result of measurability or manageability aspects. Hence, for safety performance indicator quality, only four of the criteria are assessed and suggested for such situations to shorten the acronym to ‘STAR’. A key safety indicator used in downstream process facilities, i.e. ‘dangerous fluid overfilling events’, motivated from the 2005 Texas City refinery accident, is used to illustrate the situation. The indicator is also applied to another incident, the Buncefield oil storage depot's accident in 2005, to provide a broader context for using it. The findings in this article could also be applied beyond the context studied. This means that, despite focusing on safety indicators in the process industries, the findings are considered as relevant and applicable to other types of performance indicators and to other energy industries. 相似文献
24.
Bursa is one of the largest cities of Turkey and it hosts 17 organized industrial zones. Parallel to the increase in population, rapidly growing energy consumption, and increased numbers of transport vehicles have impacts on the air quality of the city. In this study, regularly calibrated automatic samplers were employed to get the levels of air pollution in Bursa. The concentrations of CH4 and N-CH4 as well as the major air pollutants including PM10, PM2.5, NO, NO2, NOx, SO2, CO, and O3, were determined for 2016 and 2017 calendar years. Their levels were 1641.62?±?718.25, 33.11?±?5.45, 42.10?±?10.09, 26.41?±?9.01, 19.47?±?16.51, 46.73?±?16.56, 66.23?±?32.265, 7.60?±?3.43, 659.397?±?192.73, and 51.92?±?25.63 µg/m3 for 2016, respectively. Except for O3, seasonal concentrations were higher in winter and autumn for both years. O3, CO, and SO2 had never exceeded the limit values specified in the regulations yet PM10, PM2.5, and NO2 had violated the limits in some days. The ratios of CO/NOx, SO2/NOx, and PM2.5/PM10 were examined to characterize the emission sources. Generally, domestic and industrial emissions were dominated in the fall and winter seasons, yet traffic emissions were effective in spring and summer seasons. As a result of the correlation process between Ox and NOx, it was concluded that the most important source of Ox concentrations in winter was NOx and O3 was in summer. 相似文献
25.
美国制定水质基准的方法概要 总被引:5,自引:0,他引:5
水质基准保护对象不同可分为保护水生生物的水质基准和保护人体健康的水质基准。概要介绍了美国推导这两种水质基准的方法及其数据要求。 相似文献
26.
27.
Delhi is one of the many megacities struggling with punishing levels of pollution from industrial, residential, and transportation
sources. Over the years, pollution abatement in Delhi has become an important constituent of state policies. In the past one
decade a lot of policies and regulations have been implemented which have had a noticeable effect on pollution levels. In
this context, air quality models provide a powerful tool to study the impact of development plans on the expected air pollution
levels and thus aid the regulating and planning authorities in decision-making process. In air quality modeling, emissions
in the modeling domain at regular interval are one of the most important inputs. From the annual emission data of over a decade
(1990–2000), emission inventory is prepared for the megacity Delhi. Four criteria pollutants namely, CO, SO2, PM, and NO
x
are considered and a gridded emission inventory over Delhi has been prepared taking into account land use pattern, population
density, traffic density, industrial areas, etc. A top down approach is used for this purpose. Emission isopleths are drawn
and annual emission patterns are discussed mainly for the years 1990, 1996 and 2000. Primary and secondary areas of emission
hotspots are identified and emission variations discussed during the study period. Validation of estimated values is desired
from the available data. There is a direct relationship of pollution levels and emission strength in a given area. Hence,
an attempt has been made to validate the emission inventory for all criteria pollutants by analyzing emissions in various
sampling zones with the ambient pollution levels. For validation purpose, the geographical region encompassing the study area
(Delhi) has been divided into seven emission zones as per the air quality monitoring stations using Voronoi polygon concept.
Dispersion modeling is also used for continuous elevated sources to have the contributing emissions at the ground level to
facilitate validation. A good correlation between emission estimates and concentration has been found. Correlation coefficient
of 0.82, 0.77, 0.58 and 0.68 for CO, SO2, PM and NO
x
respectively shows a reasonably satisfactory performance of the present estimates. 相似文献
28.
29.
30.
To study the occurrence conditions and propagation characteristics of deflagration to detonation transition (DDT) in linked vessels, two typical linked vessels were investigated in this study. The DDT of the methane–air mixture under different pipe lengths and inner diameters was studied. Results showed that the CJ detonation pressure of the methane–air mixture was 1.86 MPa, and the CJ detonation velocity was 1987.4 m/s. Compared with a single pipe, the induced distance of DDT is relatively short in the linked vessels. With the increase in pipeline length, DDT is more likely to occur. Under the same pipe diameter, the DDT induction distance in the vessel–pipe–vessel structure is shorter than that in the vessel–pipe structure. With the increase in pipeline diameter, the length of the pipe required to form the DDT is reduced. For linked vessels in which detonation formed, four stages, namely, slow combustion, deflagration, deflagration to detonation, and stable detonation, occurred in the vessels. Moreover, for a pipe diameter of 60 mm and a length of 8 m, overdriven detonation occurred in the vessel–pipe–vessel structure. 相似文献