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981.
为定量化评估盾构隧道施工过程中管片上浮给隧道造成的损伤,作者提出将常见的损伤分为管片间变形、管片裂缝、管片表面剥落、沉降、渗漏水、断面整体变形、螺栓受到过大剪力以及管片受到过大水土压力等8大类。采用相关系数法选取15个底层指标,建立管片上浮致伤诊断指标体系。通过模糊变换对全部底层指标进行量纲一化处理,结合提出的融合赋权方法,构建管片上浮致伤诊断模型。最后,基于理想点法对中国湖南某盾构隧道管片上浮致伤情况进行诊断研究。结果表明,模型能有效评估管片上浮对隧道造成的损伤,诊断结果与工程实际情况及专家论证结果基本相符。  相似文献   
982.
The translation of the framework directive 89/391/EEC (Council Directive 89/391/EEC) into national law aims at supplying occupational protection and health care to all employees of large, small, and medium-sized enterprises (SMEs) likewise, depending on assessed exposure. Prior incomplete protection of the German workforce with bias against the SMEs requires an assessment of quantitative and qualitative adequacy of present occupational health care practice and also of future needs.

Therefore, the Federal Institute for Occupational Safety and Health of Germany initiated a study to evaluate the present state of occupational health care in 4 regions with different geographic and economic structure. Based on these data the future demand for adequately trained occupational physicians will be estimated by employing a statistical method that allows for including a large number of modifying variables (economic development, demographic change, etc.).

Expected result of the applied technique are the estimated minimal and maximal number of occupational physicians that have to be trained to meet future demand. In the same study models of best practice will be identified and evaluated for general application. The project started in October 1997 and will be finished by January 2000.  相似文献   
983.
The study deals with working conditions in small private enterprises in Poland. Data come from 50 small enterprises from the Warsaw area. Information about the evaluation of working conditions and the existence of programmes for their improvement was gathered with the help of questionnaires addressed to employees and employers. The results constitute a ‘photograph’ of the Polish reality at the beginning of its transition from planned to market economy. The study revealed a lack of programmes for the improvement of working conditions in a significant number of the enterprises studied as well as little interest in occupational safety on the part of employers (owners).

The study also revealed that all decisions—including those about the improvement of working conditions—were made by employers. Hence, the need for the widest possible dissemination of knowledge on occupational safety and the protection of human in the working environment with particular stress put on employers. Employers who are knowledgeable in this field and who are aware of its importance can significantly influence the improvement of working conditions in small enterprises.  相似文献   
984.
We analyzed occupational exposure to potentially infectious body fluids among health care workers (HCWs). Nurses were the most common exposed category of HCWs. In 73.6% cases needle sticks had been the reason of exposure. Recapping a needle was the cause of exposure in 6.9% accidents. Among 189 registered HCWs, 66 (34.9%) performed invasive procedures without any personal protective equipment. Prophylaxis with antiretroviral drugs was necessary in 43 (22.8%) cases.

As many as 60.3% of exposure incidents to potentially infectious material result from non-compliance with the relevant recommendations. Continuous education and training is critically needed to prevent occupational exposure to blood-borne infections among health care workers.  相似文献   
985.
Exposure to methyl methacrylate (MMA), total dust and health symptoms were investigated in 20 dental laboratories located in Tehran, Iran. Time-weighted average (TWA) of MMA and peak concentrations were determined, using XAD-2 tubes followed by GC-ID analysis. Total dusts were evaluated gravimetrically. Health symptoms were asked using a questionnaire. TWA for technicians with direct and indirect exposure to MMA were 327.28 ± 79.42 and 282.9 ± 41.84 mg/m3 , respectively. Peak concentration of MMA for those technicians were 337.0 ± 36.81 and 328.88 ± 45.40 mg/m3, respectively.

There were no significant differences between TWA of MMA and peak concentration in different weekly workdays; however, within-day variations were observed (P < .05).

TWA of MMA and peak concentration correlation with the laboratory volume were 0.61-0.65. Dust exposure of technicians was 2.35 ± 2.70 mg/m3. Cough and skin dryness were the common health symptoms. Smoking and asbestos exposure history were factors influencing cough prevalence (p < .05).

It is concluded that the current Short-Term Exposure Limit (STEL) is not low enough to protect technicians against the adverse effects caused by MMA.  相似文献   
986.
Employers and workers need concrete guidance to plan and implement changes in the ergonomics of computer workstations. The Näppärä method is a screening tool for identifying problems requiring further assessment and corrective actions. The aim of this study was to assess the work of occupational safety and health (OSH) government inspectors who used Näppärä as part of their OSH enforcement inspections (430 assessments) related to computer work. The modifications in workstation ergonomics involved mainly adjustments to the screen, mouse, keyboard, forearm supports, and chair. One output of the assessment is an index indicating the percentage of compliance items. This method can be considered as exposure assessment and ergonomics intervention used as a benchmark for the level of ergonomics. Future research can examine whether the effectiveness of participatory ergonomics interventions should be investigated with Näppärä.  相似文献   
987.
The main purpose of this study is to gather information about the dimensions of the northern Colombian (Caribbean region) population, focusing on the dimensions of the hand and comparing them with measurements from other regions. Thirty-two hand dimensions were chosen and 120 males and 86 females were measured. Results indicated that there were differences between the dimensions of the hand for men and women, showing that men are larger. Also, there was a comparison made between some measurements of other studies in different regions of Colombia, the USA, Chile, Jordan, Korea and Japan. The results indicated important physiological differences between regions in Colombia and across countries. It was therefore concluded that differences in anthropometric measurements must be included in the design and procurement of machinery and apparatus in order to avoid productivity loss, occupational injuries or illness.  相似文献   
988.
吕梁矿区某矿山西组煤层受奥陶系灰岩含水层和太原组灰岩含水层高承压水威胁,工作面回采时发生了底板突水.为了快速、准确判别突水水源类型,分析突水原因并制定合理的治理措施,采用灰色关联度法分析水质关联度,利用弹塑性理论计算了煤层采动后底板最大破坏深度,分析了隔水层厚度及岩性组合的隔水性能.分析结果表明,煤层底板隔水层厚度平均26m,且软岩所占比例达到62.18%,灰色关联度分析突水水源接近太原组灰岩水,底板最大破坏深度26.7m,距离煤壁22.4m,与实际突水点吻合,判断突水水源为太原组灰岩水.  相似文献   
989.
船舶漏油事故等导致海洋环境污染的案例推动了船舶污染海洋环境应急管理和立法的发展。2011年交通运输部颁布的《船舶污染海洋环境应急防备和应急处置管理规定》及最高人民法院发布的《关于船舶油污损害赔偿纠纷案件若干问题的规定》等确立了以下机制:行政主体依民事侵权程序向责任人请求返还应急费用;应急产业经营者依强制缔约合同请求支付应急处置费用;以责任社会化的方式保障应急费用的资金来源。为应对海洋石油开发等其他类型的海洋环境污染事故,我国应借鉴船舶污染海洋应急管理中的强制清污协议制度、强制保险制度、油污基金制度等,建立环境损害赔偿制度。  相似文献   
990.
麻水歧  王莉 《灾害学》1990,(3):38-43
本文给出了企事业单位的震害预测方法。其特点是:与当地地震危险性分析和场地地震动参数相结合;把结构的整体动力计算与薄弱部位抗震构件验算和普查结果相结合;把建筑物的震害预测与震害调查和试验研究结果相结合。  相似文献   
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