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751.
The basis of the manSievert as a unit for collective radiation dose is discussed and previous recommendations are considered for how much should be spent to avert a collective dose of 1 manSv. New calculations are given using the J-value method. It is shown that the value to be assigned to averting a manSievert depends on the duration of averted exposure as well as on the net discount rate and the loan rate thought to be appropriate. Different figures will result depending on whether the exposed group consists of workers or the general public. The variation with dose duration is so large that it is not possible to recommend a single figure for the value of a manSievert. Instead, tables are given at two conservative, loan and net discount rates for the value of a manSievert as a function of exposure time. The base data for the J-value method need to be updated annually, and this means that the values given in the tables will increase over time as people live longer and become richer. 相似文献
752.
Establishing the relationship between level of safety climate and safety performance is a current challenge. This work examines the relationship between level of safety climate and orientation toward safety in the decision making process and choice. Alternatively, this work seeks to answer the question of whether level of safety climate can predict safety-oriented decision making. A generalized safety climate questionnaire and a decision making simulation are utilized to examine this relationship. The results indicate that level of safety climate is not a significant predictor of the decision process; however, it was found to be a significant predictor of the selection of safer choices. 相似文献
753.
Brigitte Cambon de Lavalette Charles Tijus Sbastien Poitrenaud Christine Leproux Jacques Bergeron Jean-Paul Thouez 《Safety Science》2009,47(9):1248-1253
Among road users, pedestrians are those whose continued trajectory is the less constrained by the environment and by the regulation rules. Consequently, the choice of where, when and how to cross roads are more or less conforming with the awaited behavior. Proceeding with an experimental approach, from observations of pedestrian crossings to the modeling of the decision-making process, a categorization of both environments and of pedestrian behavior is proposed. 相似文献
754.
E. Battisti A. Albanese L. Bianciardi A. I. Fiaschi M. Rigato A. Vittoria G. L. Messa N. Giordano 《The Environmentalist》2009,29(2):190-195
The utility and the safety of the extremely low frequencies (ELF) electromagnetic fields in the treatment of numerous diseases
have been demonstrated. Moreover, the effects of these fields seem to depend on their respective codes (frequency, intensity,
waveform). We want to value the effects and the safety of the therapeutic application of a musically modulated electromagnetic
field (TAMMEF) system, which field is piloted by a musical signal and its parameters (frequency, intensity, waveform) are
modified in time, randomly varying within the respective ranges, so that all possible codes can occur during a single application.
Sixty subjects, affected by shoulder periarthritis were enrolled in the study and randomly divided into three groups of 20
patients each: the first exposed to TAMMEF, the second exposed to ELF, the third exposed to a simulated field. All subjects
underwent a cycle of 15 daily sessions of 30 min each and a clinical examination upon enrolment, after 7 days of therapy,
at the end of the cycle and at a follow-up 30 days later. All the patients of TAMMEF group and ELF group completed the therapy
without the appearance of side effects: they presented a significant improvement of the subjective pain and the functional
limitation, which remained stable at the follow-up examination. In those exposed to a simulated field group, there was no
improvement of the pain symptoms or articular functionality. This study suggests that the TAMMEF system is efficacious and
safe in the control of pain symptoms and in the reduction of functional limitation in patients with shoulder periarthritis.
Moreover, the effects of the TAMMEF system cover those produced by the ELF field. 相似文献
755.
基于安全等级的地铁车站火灾人员安全疏散方案及其工程应用 总被引:1,自引:0,他引:1
地铁火灾安全特别是大型复合地铁车站的火灾安全得到了广泛关注,合理有效的车站人员疏散方案设计是保障地铁车站火灾时人员安全的关键所在.针对地铁车站人员疏散特点,以人员安全疏散准则和现行地铁设计规范为基础,融合了火灾安全工程学的性能化人员疏散设计思路,分别将事故疏散时间和烟控可用安全疏散时间划分为三个等级,综合形成了四类人员疏散安全等级标准,并在此基础上提出了框架性的基于安全等级的地铁车站火灾人员安全疏散方案设计流程.该流程着重采用了自动扶梯反转及列车辅助疏散等措施提高人员的安全性,并结合某大型复合地铁车站的工程案例验证了该疏散方案的可行性.该文的研究工作可为地铁车站人员疏散设计和应急预案制定提供参考. 相似文献
756.
生物泥浆反应器中微生物数量变化与PAHs降解 总被引:4,自引:0,他引:4
分别以浓度、温度、接种量、通气量和表面活性剂为降解调控因子,采用平板记数法进行了生物泥浆反应器中微生物数量变化与PAHs降解的关系研究。结果表明:土壤中细菌数量与PHE、PY投加浓度呈显著正相关。PHE、PY初始浓度越高,细菌数量越大。此外,反应器的温度对微生物生长速度和数量有重要影响。反应器温度为30℃时对细菌迅速繁殖有利,反应器温度为20℃时对真菌生长繁殖有利。接种量为5%即可明显提高PHE和 相似文献
757.
The limited and sporadic interaction between EIA and planning theory has meant that EIA has largely failed to benefit from planning theory insights and lessons. Obstacles and dilemmas already encountered and addressed in planning theory are still hampering EIA theory building and practice. An overview of the characteristics, strengths, and limitations of five major planning theories—rationalism, pragmatism, socio-ecological idealism (SEI), political-economic mobilization (PEM), and communications and collaboration (CC) is presented in an effort to ameliorate this problem. EIA parallels to each planning theory and lessons for EIA are identified. Also addressed are the application of planning theories to different context types, overlaps, interconnections and middle ground concepts among theories, the integration of values, ethics, and postmodern perspectives and the potential to construct composite theories. 相似文献
758.
Impact of poor solid waste management on ground water 总被引:1,自引:0,他引:1
Eight sediment cores recovered from Tamaki Estuary were analysed for Cu, Pb, Zn, and Cd using downward cored sub-samples.
The results indicate a significant upward enrichment in heavy metals with the highest concentrations found in the uppermost
0–10 cm layer. Assessment of heavy metal pollution in marine sediments requires knowledge of pre-anthropogenic metal concentrations
to act as a reference against which measured values can be compared. Pristine values for the cored sediments were determined
from flat “base-line” metal trends evident in lower core samples. Various methods for calculating metal enrichment and contamination
factors are reviewed in detail and a modified and more robust version of the procedure for calculating the degree of contamination
is proposed. The revised procedure allows the incorporation of a flexible range of pollutants, including various organic species,
and the degree of contamination is expressed as an average ratio rather than an absolute summation number. Comparative data
for normalized enrichment factors and the modified degree of contamination show that Tamaki Estuary sediments have suffered
significant systematic heavy metal contamination following catchment urbanization. Compared to baseline values the uppermost
sediment layers show four-fold enrichment averaged across eight cores and four analysed metals. 相似文献
759.
INTRODUCTION: Gender differences were investigated in a sample of persons (N=34,755) who completed the driver's license theory test in the Netherlands. RESULTS: Contrary to recent findings from Sweden, no gender differences were found. IMPACT OF INDUSTRY: The present study signifies the importance of standardization in driver testing. 相似文献
760.
Quick BL Stephenson MT Witte K Vaught C Booth-Butterfield S Patel D 《Journal of Safety Research》2008,39(3):329-338
PROBLEM: The National Institute for Occupational Safety and Health's [NIOSH] National Occupational Research Agenda (DHHS Publication No. 96-115) reports that approximately 50% of miners will experience hearing loss by age 50, compared to only 9% of the general population. The present investigation examines three antecedents believed to be associated with miner's use of hearing protection. METHOD: A posttest-delayed-posttest-control group field research design was employed to assess antecedents toward wearing hearing protection. RESULTS: Following the initial posttest, miners' attitudes and subjective norms were antecedents to intentions to wear hearing protection devices. Also, intentions toward wearing hearing protection predicted hearing protection behaviors. Approximately six weeks later, miners' attitudes and perceived behavioral control were each significant predictors of intentions to wear hearing protection and again, intentions were positively associated with hearing protection behaviors. IMPACT ON INDUSTRY: Our results indicate that appeals to normative influences may be the most effective antecedent to employ when persuading coal miners to wear hearing protection. However, messages designed to impact attitudes and perceived behavioral control were also effective. 相似文献