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1.
为了对钢铁企业安全投资进行模糊综合评价,建立了钢铁企业安全投资的评价体系,确定各因素的权重。得出模糊综合评价矩阵,可对各因素进行评价分析;得出某钢铁企业安全投资现状分数为83.9分,等级为较好,需着重加强安全培训、劳保品、工业卫生等人因素方面的投资;在环境方面的投资较合理。  相似文献   
2.
分层开采是厚煤开采的经典工艺,这种工艺对地表沉降的影响比较复杂。通过测试原岩物理力学参数,利用有限元软件flac3D对分层和一次采全高时地表沉降进行了数值模拟。结果表明,如果采高较小,砌体梁距煤层较近,且采完上分层后长时间停采,给顶板再生留足时间,分层开采较一次采全高对地表沉降影响要小。  相似文献   
3.
Abstract

Objective: With the overall goal to harmonize prospective effectiveness assessment of active safety systems, the specific objective of this study is to identify and evaluate sources of variation in virtual precrash simulations and to suggest topics for harmonization resulting in increased comparability and thus trustworthiness of virtual simulation-based prospective effectiveness assessment.

Methods: A round-robin assessment of the effectiveness of advanced driver assistance systems was performed using an array of state-of-the-art virtual simulation tools on a set of standard test cases. The results were analyzed to examine reasons for deviations in order to identify and assess aspects that need to be harmonized and standardized. Deviations between results calculated by independent engineering teams using their own tools should be minimized if the research question is precisely formulated regarding input data, models, and postprocessing steps.

Results: Two groups of sources of variations were identified; one group (mostly related to the implementation of the system under test) can be eliminated by using a more accurately formulated research question, whereas the other group highlights further harmonization needs because it addresses specific differences in simulation tool setups. Time-to-collision calculations, vehicle dynamics, especially braking behavior, and hit-point position specification were found to be the main sources of variation.

Conclusions: The study identified variations that can arise from the use of different simulation setups in assessment of the effectiveness of active safety systems. The research presented is a first of its kind and provides significant input to the overall goal of harmonization by identifying specific items for standardization. Future activities aim at further specification of methods for prospective assessments of the effectiveness of active safety, which will enhance comparability and trustworthiness in this kind of studies and thus contribute to increased traffic safety.  相似文献   
4.
为减少事故损失,必须对矿热炉安装施工危险源进行分析。基于此,对矿热炉安装工序中最重要工序炉壳安装应用作业危险性分析进行分析。将炉壳安装作业分成3大部分,用鱼刺图分析方法进行分析,总结出矿热炉炉壳安装中事故发生的主要原因并提出对策措施,以预防和减少事故的发生。  相似文献   
5.
为检验交通公益广告中情感诉求变化对广告效果的影响,采用试验法操作广告情感诉求类型,使用眼动技术和Go/no-go联想测验(GNAT),通过比较不同效价和唤醒度的情感诉求广告对受众的注意力和内隐态度的影响,评估交通安全广告情感诉求类型的说服效果。研究发现:被试对低唤醒广告文字区的眼动注视时间和注视点个数显著长于/多于对高唤醒广告文字区的注视时间和注视点个数;被试观看高唤醒消极的广告后,正确驾驶行为的积极态度显著下降,而低唤醒消极/高唤醒积极/低唤醒积极的公益广告对于被试的内隐态度的改变没有显著差异。结果表明,高唤醒度积极广告能够提升受众的注意力,而高唤醒度消极广告则会损害受众对正确驾驶行为的内隐态度。  相似文献   
6.
地下开采对地表的破坏与防治   总被引:5,自引:0,他引:5  
介绍了由于地下开采而引起的沉陷对环境的破坏,包括连续下沉的移动盆地、非连续下沉的塌陷坑等。同时还介绍了对留设保护矿柱、充填采空区等预防措施。对塌陷区和裂缝的治理、复地造田等方法进行了探讨。  相似文献   
7.
由于我国对企业特别是海外来大陆投资的企业,缺乏严格的安全管理手段,致使不少企业屡次出现安全事故。为了减少企业安全事故的发生,提高企业安全度,要求企业在贯彻“安全第一,预防为主”的基本方针的基础上。建立“以人为本。以制度和伦理道德为约束的人性化的安全管理系统”。本文给出了该系统的模型,并对此模型进行了分析和解释,探讨了相关的几个理论基础,最后给出了人性化安全管理的实质。通过该系统的管理执行,使企业在尊重人权、尊重生命的前提下发展壮大,最终实现安全的全球化。  相似文献   
8.
The coastal water of northeast Taiwan island, called 'Yin-Yang Hai' for its distinct yellow colour compared with blue offshore water, was investigated from 1989 to 1990 by the authors. Biological study showed the dominant species of plankton to be Copepoda, Cladocera, planktonic eggs and Diatoma. Dominant species of benthos were young crabs, Amphipoda and Annelida, with Amphipoda usually occurring in heavily polluted areas. Heavy metal data showed that the concentration of copper was high. the copper and iron concentration in algae of the intertidal zone was also high. the concentrations of iron and copper in inshore water were also higher than in offshore water. By comparison of the pH and salinity distribution of this area, we conclude that this coastal water has been polluted by acid waste water from coastal industry. the suspended solids concentration in sea water is high. Flocculation occurring at the boundary of fresh and saline water might be a reason for the distinct yellow colour of the water of this area. Further study is required.  相似文献   
9.
以广西柳州泗顶铅锌矿区的玉米地、菜地、灌木、尾矿库、森林和柑橘园6种不同利用类型土壤为研究对象,采用高通量测序技术,分析了不同土地利用类型土壤微生物群落结构特征及土壤环境因子对微生物群落结构的影响.结果表明,变形菌门(Proteobacteria)是6种土壤的优势菌门,所占比例为31.34%~53.47%,γ-变形菌纲(Gammaproteobacteria)为优势菌纲.冗余分析表明,在重金属含量最高的灌木区,厚壁菌门(Firmicutes)和拟杆菌门(Bacteroidetes)的丰度与土壤中铅、锌、镉、铜的含量呈现显著正相关;在土壤钠和钾含量较高的玉米地和菜地,浮霉菌门(Planctomycetes)的丰度有所增加,而厚壁菌门和拟杆菌门的丰度则有所下降.在土壤有机质含量较高而总氮、总磷含量较低的柑橘园,酸杆菌门(Acidobacteria)和疣微菌门(Verrucomicrobia)的丰度较高.芽单胞菌门(Gemmatimonadetes)和浮霉菌门的丰度与土壤pH值呈显著正相关.研究结果表明土地利用类型及土壤环境因子对土壤微生物群落结构多样性有显著的影响.  相似文献   
10.
Nahanni National Park Reserve is located at southwestern NWT-Yukon border. One of the first UNESCO World Heritage sites, Nahanni lies within Taiga Cordillera and Taiga Shield Ecozones. Base and precious metal mining occurred upstream of Nahanni prior to park establishment. Nahanni waters, sediments, fish, and caribou have naturally elevated metals levels. Baseline water, sediment and fish tissue quality data were collected and analyzed throughout Nahanni during 1988–91 and 1992–97. These two programs characterized how aquatic quality variables are naturally varying in space and time, affected by geology, stream flow, seasonality, and extreme meteorological and geological events. Possible anthropogenic causes of aquatic quality change were examined. Measured values were compared to existing Guidelines and site-specific objectives were established.  相似文献   
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