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971.
随着矿产资源不断向地层深部开采,矿井亦不断延伸,尤其是千米深井日渐增多,矿井动力提升速度和提升功能不断加快、增强,矿井数字化水平提高,对矿井动力操控员工的心理反应能力、注意能力、时空判断能力等一系列心理素质水平的要求不断增强。员工的反应准确性、注意集中和分配能力及情绪稳定性和人格状况是构成影响员工操控行为安全稳定的核心心理品质。探究矿井动力提升系统操控员工的各项安全心理阈限值及其安全心理参数标准,建立员工安全心理选拔准入制,是保障矿井人一机和谐安全运行的重要措施。 相似文献
972.
增加粮食收益的市场对策 总被引:4,自引:0,他引:4
课题组 《河北经贸大学学报》2001,22(3):79-83
粮食在国民经济中的重要地位决定粮食收益问题受到各国政府的普遍关注。基于此,文章在深入分析粮食收益下滑原因的基础上,提出了增加粮食收益的市场对策,即在政府宏观调控下,依据市场规律建立优势突出、结构合理、运作高效的粮食生产、流通体系。 相似文献
973.
In this paper, we study strategic asset allocation for China's foreign reserves using a risk- based approach. Four aspects of the risk management are investigated: an investment universe, dependence structure, allocation strategies under risk minimization and trade-off between risks and returns. A regime-switching copula model is developed to investigate the dynamic dependence between assets. One regime emphasizes a short-term safe asset and the other regime emphasizes a long-term safe asset. The optimal allocation is derived following two strategies: risk minimization and trade-off between risks and returns in utility maximization with disappointment avoidance, lf the central bank focuses solely on risk minimization, the asymmetries in the asset return dependence encourage the flight to safety. However, if higher risks are allowed in exchange for higher returns, even the exchange is very conservative, and the asymmetries would discourage the flight to safety. Therefore, we suggest that China should mitigate its flight to safety after 2008 and increase holdings of short-term bank deposits, long-term treasury bonds and euro bonds. 相似文献
974.
本文通过实验室模拟仓实验,研究了碎麦提取物与锈赤扁谷盗Cryptolestes ferrugineus、、锯谷盗Oryzaephilus surinamensis、赤拟谷盗Tribolium castaneum、玉米象Sitophilus zeamais、米象Sitophilus ory zae、谷蠹Rhyzopertha dominica信息素提取物混合诱捕储粮害虫效果的影响:本实验应用6种储粮害虫信息素提取物与碎麦提取物混合分别对多种储粮害虫进行诱捕,发现当多种害虫共存时,碎麦提取物与害虫信息素提取物混合对同种害虫的诱捕超过了单独使用碎麦提取物或同种害虫的信息素提取物的诱捕效果,而对于其它害虫的诱捕也都有较显著的增强作用。如碎麦提取物与米象信息素提取物混合除了对米象诱捕有增强作用外,对玉米象也有较好的诱捕作用;结果再次证明昆虫信息素结合食物引诱剂对监测害虫,特别是储粮害虫有较好的增效作用。 相似文献
975.
976.
Dirk van Aken 《International journal of injury control and safety promotion》2013,20(3):151-156
The concept of risk appears in a prominent way in the recently revised European Directive on General Product Safety (GPSD). Risk assessment is therefore an important tool for the success of the Directive; the question is how risk assessment should be carried out in a systematic manner in order to meet the aims of the Directive. In this paper, the references in the GPSD concerning the concept of risk are reviewed and compared with reported problems in European risk assessment. Existing guidelines for risk assessment are examined in order to determine what factors determine the consistency of the outcome. This leads to recommendations for a process that could be followed in order to make risk assessment successful in the context of the GPSD. On the basis of existing guidelines for risk assessment, criteria are formulated with which methods of risk assessment should comply. A stepwise process is proposed in order to develop a common method of risk assessment that can be applied in Europe to support the GPSD. The requirements for risk management in the new GPSD are rather and lack specification, both for producers and for enforcement authorities. The Directive further refers to the need to develop non-binding guidelines in due course. Sources of different outcomes of the risk assessment process are outlined in this paper as well as possibilities to achieve a more consistent basis for decisions, more uniformity and transparency. These are essential conditions if one wishes to avoid both undue trade barriers and unsafe products on the market. A leading role for the European Commission seems necessary to make sure that the intentions of the GPSD are accomplished. 相似文献
977.
Francisco Tercero Ragnar Andersson Julio Rocha Néstor Castro Leif Svanström 《International journal of injury control and safety promotion》2013,20(1):33-42
Background Regularly available data has been shown to be inadequate for developing, implementing, and evaluating injury prevention and control programs in Nicaragua. A specific prevention-oriented local injury surveillance system has therefore been set up in the city of León. Objectives The aim of this paper is to describe the epidemiology of fatal and non-fatal injuries over a one-year period in a well-defined local population in Nicaragua, as emerging from the perspective of emergency room and inpatient treatments over a one-year period. Methods A hospital-based injury surveillance system was established to collect data for different levels of severity. All treated unintentional and intentional injuries were registered, including information on the external causes according to the ICD-9. Results Of all emergency room visits, 15.9% (9,970) were injuries. For every death due to injuries, there were 31 hospital admissions and 253 emergency room visits. Home and street/roads were the main arenas for the accidents. The estimated underreporting rate was about 6%, and in 20.3% of the cases, no E-code was assigned. The overall incidence and mortality rates were 56.2 per 1,000 and 20 per 100,000 inhabitants, respectively. However, comparison with a parallel household survey showed that the reporting rate of the surveillance system is only about 9%. The overall ratio of male to female injury rates was 2.1 to 1. The main causes of non-fatal injuries were falls, whereas the main cause of death was traffic accidents. Conclusions Hospital discharge and emergency room data systems are effective and feasible means for collecting the data needed to prevent injuries. However, in a country like Nicaragua with limited access to hospital health services, it is necessary to supplement such a system with additional sources of information in order to gain a more comprehensive picture of injury occurrence. 相似文献
978.
Adnan A. Hyder Shams Arifeen Nazma Begum Steven Fishman Salman Wali Abdullah H. Baqui 《International journal of injury control and safety promotion》2013,20(4):205-210
The study focuses on children less than 5 years old and explores the epidemiological profile and correlates of drowning as a challenge to child survival in Bangladesh. Two data sources from Bangladesh, a cohort of 8,070 children followed for 2 years in a rural area and a nation-wide survey conducted in 1996–97 have been used. In addition, a systematic review of the literature has been conducted spanning the past two decades for analysis of drowning in children. Seventy drowning deaths were reported in the cohort and 726 deaths were reported in the national survey. Verbal autopsy and semi-structured interviews were conducted on all deaths. Drowning accounted for 43% of deaths in the cohort and 20% of deaths in 1–4-year-old children in the national survey. Most drowning deaths were in 12–23 month old children from falling into ditches and ponds. Communities provided valuable insights on possible interventions to reduce deaths due to drowning. Drowning is a newly recognized challenge for Bangladesh. Considerable research and programmatic work is required to understand the nature of the problem and develop appropriate interventions. This paper calls on aid agencies to create opportunities for drowning research and action in their work plans for the country. 相似文献
979.
980.
本文分析了不完善粒超标小麦最低收购价收购的现实需要及意义,探讨了做好收购工作的基本思路及解决收购中相关问题的建议和看法,对如何做好不完善粒超标小麦最低收购价收购工作具有一定借鉴意义. 相似文献