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101.
民用产品与非研发产品的保障性研究   总被引:1,自引:1,他引:0  
开发利用民用产品与非研发产品作为军方的后勤保障源是一项重要的战略任务。论述了民用产品与非研发产品的保障性要求,诠释了民用产品与非研发产品保障性分析和保障性分析过程中的要素。对民用产品与非研发产品的信息需求进行了归纳。  相似文献   
102.
Fluctuations in the abundance of insular groups of sea otters on the Commander Archipelago are analyzed with regard to changes in meteorological conditions. The main factors responsible for the abrupt decline of the Bering Sea group between 2002 and 2004 are discussed. A statistically significant correlation has been revealed between fluctuations of sea otter abundance and the cycles of solar activity in the period since 1992. Changes in the age and sex structure of the insular groups of sea otters are evaluated.  相似文献   
103.
惠州市惠城区水口镇原隶属于惠阳市,2003年惠城区行政区划进行了战略性调整,惠阳撤市设区,水口镇划归惠城区管辖, 这样水口镇现执行的基准地价标准(原惠阳标准)需要更新.目前基准地价的评估方法有很多种,通过建立样点地价与土地定级网格单元总分值关系模型,运用回归分析来测算水口镇商业用地基准地价.  相似文献   
104.
高校宣传思想工作者要抓住宣传思想工作的根本问题,不断提高自身素质,尤其要强化相关意识:党性意识、人本意识、求真意识、服务意识、民主意识、导向意识、渗透意识、阵地意识、示范意识、创新意识。  相似文献   
105.
中国“入世”后 ,其劳动标准问题与其他经济和社会领域中的问题一样 ,不可避免地越来越带有国际化的色彩。究竟我国的劳动标准处于何种水平 ?是低 ,是高 ?这需要针对劳动标准的各方面内容进行一系列的比较研究。我国女职工劳动保护标准作为劳动标准体系中的一个组成部分 ,一直是国际社会关注的热点问题之一。通过比较 ,可以认为 :就水平而言 ,我国法定的女工保护标准或者与国际标准类似 ,或者高于国际标准 ;就结构而言 ,二者的框架也大体相同。但鉴于国际劳工标准的发展趋势 ,我国女工保护标准也应考虑增加某些注重促进女工社会平等方面的内容 ,如家庭责任问题等。  相似文献   
106.
This paper examines the relationship between psychological contract breach and insomnia among older workers (aged 40 years and up). Drawing upon the conservation of resources theory, we conceptualize breach as a stressful event characterized by a perceived threat, failure to gain, or actual loss of valued resources, which increases psychological distress and insomnia. Moreover, we hypothesized that older workers' generativity concerns would act as a personal resource that would buffer the negative impact of breach. We tested our proposed model in 2 studies (Study 1 = 123; Study 2 = 168) of employee–spouse dyads. Results revealed that psychological distress mediated the relationship between psychological contract breach and insomnia. These mediated relationships were significant for those with low, but not for those with high levels of generativity concerns. These effects remained significant even after controlling for perceived organizational support (i.e., a social exchange mechanism). Theoretical and practical implications are discussed.  相似文献   
107.
Objective. The provision of appropriate personal cooling vests is recognized as an effective measure to combat heat stress. However, personal cooling vests are not widely implemented in the Hong Kong industries. The current study aims to evaluate the usability of a hybrid cooling vest that is associated with the success of its application in industrial settings. Methods. A self-administrated questionnaire focusing on 10 subjective attributes of cooling effect, ergonomic design and usability of a hybrid cooling vest was administered with 232 occupational workers in the construction, horticultural and cleaning, airport apron services and kitchen and catering industries. Results. A structural equation model estimated by analysis of moment structures was constructed to evaluate the usability of the cooling vest, as influenced by cooling effect and ergonomic design. Results showed that cooling effect (path coefficient?=?0.69, p?p?Conclusions. The structural equation model is feasible to examine the complex nature of the structural relationships among the subjective perceptions of personal cooling vests. The empirical findings furnish sound evidence for further optimization of the hybrid cooling vest in terms of cooling effect and ergonomic design for occupational workers.  相似文献   
108.
Introduction: Night work requires inversion of the natural, diurnal human activity-rest cycle and is associated with decreased alertness and some measures of performance, reduced safety, adverse health effects, and chronic disruption of the melatonin cycle that has been associated with increased risk for several major diseases. Previous studies show that red light exposures at night can promote alertness and improve performance while not negatively affecting melatonin secretion. Method: This ongoing crossover, mixed (within- and between-subjects) design field study is testing the efficacy and acceptance of red light delivered to day-shift and night-shift workers using personal light glasses while they are at work. Each participant experienced three lighting interventions at the eyes: red light (50 lx, 630 nm, the treatment intervention), blue light (50 lx, 460 nm, the positive control intervention), and dim white light (10 lx, 3,000 K, the placebo control). During the interventions, participants underwent visual performance testing, submitted salivary melatonin and cortisol samples, and provided subjective reports of sleepiness, sleep disturbance, and general health over the 20-week protocol. Due to the ongoing nature of the study, only the performance and subjective reports are presented here. Results: Preliminary results indicate that response times were improved by the red and blue interventions, but not accuracy and hit rates. Blue light was associated with improvements to self-reported sleep disturbances compared to dim light. Conclusions: These field results partially support our laboratory results that showed a positive effect of red light for promoting alertness and certain performance outcomes during the day and at night. Practical Applications: Red light may be used to improve response times in shift workers. Continued research will elucidate the lighting interventions’ effects on melatonin and objective sleep measures (actigraphy).  相似文献   
109.
Masgrau LR  Palom AR 《Disasters》2012,36(4):676-699
This paper is based on a case study of the city of Girona in Catalonia, Spain, and analyses the vulnerability of commercial establishments to floods caused by the Onyar River. A mapping and statistical approach (cluster analysis) was applied to the information obtained from 568 questionnaires answered by the shops and the workshops located in the flood risk area. The results obtained allowed the authors to determine five different flood vulnerability profiles of the commercial establishments analysed. These profiles paint a picture of little individual adaptation to the risk and the possibility of suffering, sooner or later, large economic losses due to overflowing of the Onyar River. The authors established a methodology for carrying out a detailed multidimensional analysis of the flood vulnerability of the city's commercial establishments in order to provide the foundations for local government policies and for strategies for shop owners to reduce flood vulnerability.  相似文献   
110.
The aim of this study was to develop an analytical method for the determination of residues of organophosphorus and carbamate pesticides which are widely used in Tunisia. This method involves a liquid-liquid extraction procedure followed by liquid chromatography tandem mass spectrometry (LC/MS/MS) for the identification and quantification of compounds. Ionization of molecules was performed by the electrospray mode. Multiple reactions monitoring (MRM) was the acquisition mode used for the monitoring of two MS/MS transitions for each compound. The average recoveries obtained, at three different fortification levels, ranged between 65% and 106% for most of the pesticides studied, except for methamidophos (lower than 25%).The linearity of the method was in the range of 5 to 50 μ g/L with a correlation coefficient from 0.995 to 0.999, depending on the analyte. The estimated limit of detection and limit of quantification were 2 μ g/L and 5 μ g/L, respectively. The precision of the analytical procedure was satisfactory and the coefficients of variation, evaluated at three concentration levels were lower than 15% for most pesticides studied. The application of the method was investigated in a population of agricultural workers chronically exposed to various pesticides some of which, such as carbofuran, carbendazim, methomyl and pirimicarb, were detected in some serum samples.  相似文献   
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