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51.
Objective: The Useful Field of View (UFOV) assessment, a measure of visual speed of processing, has been shown to be a predictive measure of motor vehicle collision (MVC) involvement in an older adult population, but it remains unknown whether UFOV predicts commercial motor vehicle (CMV) driving safety during secondary task engagement. The purpose of this study is to determine whether the UFOV assessment predicts simulated MVCs in long-haul CMV drivers.

Method: Fifty licensed CMV drivers (Mage = 39.80, SD = 8.38, 98% male, 56% Caucasian) were administered the 3-subtest version of the UFOV assessment, where lower scores measured in milliseconds indicated better performance. CMV drivers completed 4 simulated drives, each spanning approximately a 22.50-mile distance. Four secondary tasks were presented to participants in a counterbalanced order during the drives: (a) no secondary task, (b) cell phone conversation, (c) text messaging interaction, and (d) e-mailing interaction with an on-board dispatch device.

Results: The selective attention subtest significantly predicted simulated MVCs regardless of secondary task. Each 20 ms slower on subtest 3 was associated with a 25% increase in the risk of an MVC in the simulated drive. The e-mail interaction secondary task significantly predicted simulated MVCs with a 4.14 times greater risk of an MVC compared to the no secondary task condition. Subtest 3, a measure of visual speed of processing, significantly predicted MVCs in the email interaction task. Each 20 ms slower on subtest 3 was associated with a 25% increase in the risk of an MVC during the email interaction task.

Conclusions: The UFOV subtest 3 may be a promising measure to identify CMV drivers who may be at risk for MVCs or in need of cognitive training aimed at improving speed of processing. Subtest 3 may also identify CMV drivers who are particularly at risk when engaged in secondary tasks while driving.  相似文献   

52.
Aggregations of individual animals that form for breeding purposes are a critical ecological process for many species, yet these aggregations are inherently vulnerable to exploitation. Studies of the decline of exploited populations that form breeding aggregations tend to focus on catch rate and thus often overlook reductions in geographic range. We tested the hypothesis that catch rate and site occupancy of exploited fish‐spawning aggregations (FSAs) decline in synchrony over time. We used the Spanish mackerel (Scomberomorus commerson) spawning‐aggregation fishery in the Great Barrier Reef as a case study. Data were compiled from historical newspaper archives, fisher knowledge, and contemporary fishery logbooks to reconstruct catch rates and exploitation trends from the inception of the fishery. Our fine‐scale analysis of catch and effort data spanned 103 years (1911–2013) and revealed a spatial expansion of fishing effort. Effort shifted offshore at a rate of 9.4 nm/decade, and 2.9 newly targeted FSAs were reported/decade. Spatial expansion of effort masked the sequential exploitation, commercial extinction, and loss of 70% of exploited FSAs. After standardizing for improvements in technological innovations, average catch rates declined by 90.5% from 1934 to 2011 (from 119.4 to 11.41 fish/vessel/trip). Mean catch rate of Spanish mackerel and occupancy of exploited mackerel FSAs were not significantly related. Our study revealed a special kind of shifting spatial baseline in which a contraction in exploited FSAs occurred undetected. Knowledge of temporally and spatially explicit information on FSAs can be relevant for the conservation and management of FSA species.  相似文献   
53.
Valuing biodiversity: reality or mirage?   总被引:1,自引:0,他引:1  
The objective of this paper was to consider the social value ofbiological diversity and explore if this value could be expressedin terms of a unidimensional metric in money. Economics distinguishes between use-values and non-use-values, which are critically evaluated for valuing biodiversity. It is shown that these utility-based valuations have severe limitations as they treat species in isolation from their ecological contexts. In contrast, ecosystem ecology regards ecosystems as an integratednon-linear and nonconvex system in which ecosystem functions canbe understood as a four-component cycle; exploitation, accumulation of biomass, creative destruction and renewal. Withinsuch a cycle, ecosystems can be seen to have two properties: stability and resilience. A good proxy for resilience is the probability of extinction of species, and social value of biodiversity can be expressed as a partial ordering with thisprobability as an index. This approach is consistent with decision theory, of which social choice is an important component, pioneered by Arrow.  相似文献   
54.
本文对GB8965.1-2009《防护服装阻燃防护第一部分:阻燃服》标准的特点、整体框架、新增项目的目的及内容进行具体阐述,并提出标准修订及实施的建议。  相似文献   
55.
北京西单立体交通工程施工安全风险模糊分析   总被引:2,自引:1,他引:1  
随着我国大规模城市地下空间的开发 ,需要分析和研究城市地下空间施工的安全风险。笔者结合北京西单立体交通工程 ,采用层次分析理论 ,探讨和分析施工过程的安全风险 ,定义施工中涉及的六大类主要安全风险 ;运用数学集合理论 ,建立风险因素集合论域U和分析评判集合论域V ,采用模糊数学理论 ,将风险因素集合论域U和分析评判集合论域V建立模糊映射关系和模糊关系 ,从而确定数学模型 ;根据西单立体交通工程施工安全风险调查采样分析 ,统计计算风险权重和建立模糊矩阵 ,定性、定量地比较了 3种施工方法的安全风险 ,经过归一化处理 ,给出施工方法的安全风险量 ,明确了适合西单地区的施工方法。  相似文献   
56.
通过剖析乌鲁木齐市建设项目环境管理工作现状,从审批权限分工管理、审批人员业务素质及环境保护与城市规划协调发展等方面,找出制约建设项目环境管理的瓶颈,并提出加强和提高建设项目环境管理工作质量的途径和对策.  相似文献   
57.
城市地下综合体在大型城市中迅猛发展,而现行防火规范中对其商业部分防火分隔的要求难以满足设计需求。结合城市地下综合体的建筑特点,提出将采取加强消防设计的步行街作为防火分隔的措施,以某城市地下综合体为例,通过理论分析与数值模拟的方法,证明了该防火分隔方案能够达到现行防火规范要求的分隔效果。  相似文献   
58.
人员密度是建筑疏散设计的基础,而商业综合体人员密度具有一定的特点。运用黑箱理论模型及统计学相关知识,建立了商业综合体人员密度计算模型。结合两个典型商业综合体实例的调查数据,获得了商业综合体人员密度、每天不同时段的人员密度分布规律以及工作日、休息日和节假日的平均人员密度比值;提出了相应的消防管理措施。结果表明:商业综合体的人员密度小于现行规范推荐值,可为商业综合体安全疏散设计提供参考。  相似文献   
59.
通过对2012~2015年6月全国工矿商贸行业发生的较大以上次生衍生事故行业分布、地域分布、时段分布、空间分布等特征的分析,归纳总结了次生衍生事故发生的规律和特点,根据事故致因理论,对次生衍生事故原因进行了分析,并提出对策措施,为降低工矿商贸次生衍生事故发生率、减少人员伤亡提供理论支撑。  相似文献   
60.
为了研究热障效应对有顶商业步行街自然排烟的影响,采用理论分析与数值模拟相结合的方法,对不同高度及不同环境温度条件下有顶商业步行街自然排烟时顶棚附近的温度、能见度以及排烟效率进行了分析。结果表明:顶棚附近环境温度越高,自然排烟效果越差,自然排烟效率随顶棚热空气温度的升高呈现线性降低趋势;步行街高度越高,竖直方向的温度差越小,到达顶棚的烟气流速越小,排烟效率越低;当顶棚附近环境温度为45℃时,有顶商业步行街高度不宜超过35 m。  相似文献   
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