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991.
Corbacioglu S  Kapucu N 《Disasters》2006,30(2):212-233
This paper examines the problems associated with inter-organisational learning and adaptation in the dynamic environments that characterise disasters. The research uses both qualitative and quantitative methods to investigate whether organisational learning took place during and in the time in between five disaster response operations in Turkey. The availability of information and its exchange and distribution within and among organisational actors determine whether self-adaptation happens in the course of a disaster response operation. Organisational flexibility supported by an appropriate information infrastructure creates conditions conducive to essential interaction and permits the flow of information. The study found that no significant organisational learning occurred within Turkish disaster management following the earthquakes in Erzincan (1992), Dinar (1995) and Ceyhan (1998). By contrast, the 'symmetry-breaking' Marmara earthquake of 1999 initiated a 'double loop' learning process that led to change in the organisational, technical and cultural aspects of Turkish disaster management, as revealed by the Duzce earthquake response operations.  相似文献   
992.
介绍了便携式红外气体分析仪的检测方案。其检测项目与指标、检测方法可为各级环境监测站及行业监测站检测同类仪器时借鉴使用。  相似文献   
993.
城市天然气管网预警系统的研究与实现   总被引:1,自引:0,他引:1  
随着城市天然气管网密度加大,由于天然气管理手段滞后导致的天然气泄漏事故急剧增加。基于GIS技术并结合燃气管网定量风险分析(QRA)模型,提出利用定量风险分析模型实现管网风险预警的方法。结合C#+ArcEngine编程技术,开发城市天然气管网预警系统,实现管网失效率分析、燃气事故扩散模拟、火灾及爆炸模拟、个人风险等值线绘制、社会风险分析等功能,能够进行区域性事故后果预测、个人风险和社会风险计算、安全性评价及应急预案编制等项工作。  相似文献   
994.
The response of natural systems to atmospheric change may depend critically on species diversity and on the genetic diversity (variability) found within their respective populations. Yet, most surveys of aquatic invertebrates account for neither. This may be of particular concern for benthic populations in running waters because of the considerable variability and the fragmentary nature of these habitats (e.g. isolated watersheds). In such habitats, species with limited genetic variability and/or limited dispersal capabilities (genetically differentiated populations) may be unable to track rapid environmental change, and may be more susceptible to climatic perturbations. We present a conceptual framework to illustrate some of the potential problems of ignoring population genetics when considering the impacts of global atmospheric change. We then review a simple method to assess population genetic structure and we evaluate available data on the genetic structure of North American stream invertebrates. These data indicate that benthic taxa often consist of genetically differentiated local populations, or even previously unknown species. Accordingly, our limited knowledge of population structure among benthic invertebrates may result in the unwitting loss of genetic and/or species diversity. Enhanced taxonomic research incorporating molecular techniques is clearly warranted. Conservation strategies based on the preservation and remediation of a diversity of aquatic habitats are likely to be our best means of ensuring species and genetic diversity of invertebrate taxa.  相似文献   
995.
IntroductionChild weight and height are the basis of manufacturer and best practice guidelines for child restraint system use. However, these guides do not address behavioral differences among children of similar age, weight, and height, which may result in child-induced restraint use errors. The objective of this study was to characterize child behaviors across age in relation to appropriate restraint system use during simulated drives. Methods: Fifty mother–child (4–8 years) dyads completed an installation into a driving simulator, followed by a simulated drive that was video-recorded and coded for child-induced errors. Time inappropriately restrained was measured as the total amount of the simulated drive spent in an improper or unsafe position for the restraint to be effective divided by the total drive time. Kruskal-Wallis tests were used to determine differences across age in the frequency of error events and overall time inappropriately restrained. Results: Children in harnessed seats had no observed errors during trips. Within children sitting in booster seats there were differences in time inappropriately restrained across age (p = 0.01), with 4 year-olds spending on average 67% (Median = 76%) of the drive inappropriately restrained, compared to the rest of the age categories spending less than 28% (Medians ranged from 3% to 23%). Conclusion: Some children may be physically compatible with booster seats, but not behaviorally mature enough to safely use them. More research is needed that examines how child behavior influences child passenger safety. Practical Applications: Not all children physically big enough are behaviorally ready to use belt positioning booster seats. Primary sources of information should provide caregivers with individualized guidance about when it is appropriate to transition children out of harnessed seats. Additionally, best practice guidelines should be updated to reflect what behaviors are needed from children to safely use specific types of child restraint systems.  相似文献   
996.
Introduction: Rear-end crashes are one of the most frequent crash types in China, leading to significant economic and societal losses. The development of active safety systems – such as Automatic Emergency Braking System (AEBS) – could avoid or mitigate the consequences of these crashes in Chinese traffic situations. However, a clear understanding of the crash causation mechanisms is necessary for the design of these systems. Method: Manually coded variables were extracted from a naturalistic driving study conducted with commercial vehicles in Shanghai. Quantitative analyses of rear-end crashes and near crashes (CNC) were conducted to assess the prevalence, duration, and location of drivers’ off-path glances, the influence of lead vehicle brake lights on drivers’ last off-path glance, and driver brake onset, and the influence of off-path glances and kinematic criticality on drivers’ response to conflicts. Results: The results indicate that the Chinese truck drivers in our study rarely engage in distracting activities involving a phone or other handheld objects while driving. Instead, they direct their off-path glances mainly toward the mirrors, and the duration of off-path glances leading to critical situations are shorter compared to earlier analyses performed in Western countries. The drivers also often keep small margins. Conclusions: Overall, the combination of short time headway with off-path glances directed toward the mirror originates visual mismatches which, associated to a rapid change in the kinematic situation, cause the occurrence of rear-end CNC. When drivers look back toward the road after an off-path glance, a fast response seems to be triggered by lower values of looming compared to previous studies, possibly because of the short time headways. Practical Application: The results have practical implications for the development of driver models, for the design of active safety systems and automated driving, and for the design of campaigns promoting safe driving.  相似文献   
997.
Problem: Safety management programs (SMPs) are designed to mitigate risk of workplace injuries and create a safe working climate. The purpose of this project was to evaluate the relationship between contractors’ SMPs and workers’ perceived safety climate and safety behaviors among small and medium-sized construction subcontractors. Methods: Subcontractor SMP scores on 18 organizational and project-level safety items were coded from subcontractors’ written safety programs and interviews. Workers completed surveys to report perceptions of their contractor’s safety climate and the safety behaviors of coworkers, crews, and themselves. The associations between SMP scores and safety climate and behavior scales were examined using Spearman correlation and hierarchical linear regression models (HLM). Results: Among 78 subcontractors working on large commercial construction projects, we found striking differences in SMP scores between small, medium, and large subcontractors (p < 0.001), related to a number of specific safety management practices. We observed only weak relationships between SMP scales and safety climate scores reported by 746 workers of these subcontractors (β = 0.09, p = 0.04 by HLM). We saw no differences in worker reported safety climate and safety behaviors by contractor size. Discussion: SMP only weakly predicted safety climate scales of subcontractors, yet there were large differences in the quality and content of SMPs by size of employers. Summary: Future work should determine the best way to measure safety performance of construction companies and determine the factors that can lead to improved safety performance of construction firms. Practical applications: Our simple assessment of common elements of safety management programs used document review and interviews with knowledgeable representatives. These methods identified specific safety management practices that differed between large and small employers. In order to improve construction safety, it is important to understand how best to measure safety performance in construction companies to gain knowledge for creating safer work environments.  相似文献   
998.
Introduction: Automobile manufacturers are developing increasingly sophisticated driving automation systems. Currently, the highest level of automation available on the market is SAE Level 2, which provides sustained assistance for both lateral and longitudinal vehicle control. The purpose of this study was to evaluate how drivers’ perceptions of what behaviors secondary to driving are safe while a Level 2 system is operating vary by system name. Methods: A nationally representative telephone survey of 2005 drivers was conducted in 2018 with questions about behaviors respondents perceived as safe while a Level 2 driving automation system is in operation. Each respondent was asked about two out of five system names at random for a balanced study design. Results: The name “Autopilot” was associated with the highest likelihood that drivers believed a behavior was safe while in operation, for every behavior measured. There was less variation observed among the other four SAE Level 2 system names when compared with each other. A limited proportion of drivers had experience with advanced driver assistance systems and fewer of these reported driving a vehicle in which Level 2 systems were available. Drivers reported that they would consult a variety of sources for information on how to use a Level 2 system. Conclusions: The names of SAE Level 2 driving automation systems influence drivers’ perceptions of how to use them, and the name “Autopilot” was associated with the strongest effect. While a name alone cannot properly instruct drivers on how to use a system, it is a piece of information and must be considered so that drivers are not misled about the correct usage of these systems. Practical Applications: Manufacturers, suppliers, and organizations regulating or evaluating SAE Level 2 automated driving systems should ensure that systems are named so as not to mislead drivers about their safe use.  相似文献   
999.
Tsetse flies are the vectors of trypanosomes, the causal agent of trypanosomiasis, a widespread disease of livestock and people in Africa. Control of tsetse may open vast areas of land to livestock-keeping, with the associated benefits of developing mixed crop-livestock production systems. However, as well as possible positive impacts there are also risks: bush clearing would accelerate and cattle numbers would rise, leading to a reduction of vegetation cover, and an increase in runoff and erosion; there may also be increased pressure on conserved areas and reductions in biodiversity. The objective of this study is to show how remotely sensed and other environmental data can be combined in a decision support system to help inform tsetse control programmes in a manner that could be used to limit possible detrimental effects of tsetse control. For Zambia, a methodology is developed that combines a tree-based decision-support approach with the use of Multiple-Criteria Evaluation (MCE), within a Geographical Information System (GIS), in order to target areas for tsetse control. The results show clear differentiation of priority areas under a series of hypothetical scenarios, and some areas (e.g. northwest of Petauke in the Eastern Province of Zambia) are consistently flagged as high priority for control. It is also demonstrated that priority areas do not comprise isolated tsetse populations, meaning that disease control using an integrated approach is likely to be more economically viable than local eradication.  相似文献   
1000.
In a genetic analysis of the mating system of cooperatively breeding Arabian babblers (Timalidae: Turdoides squamiceps), we identified which individuals in the population are breeding, and how reproductive success was distributed among group members with respect to their dominance rank, for both males and females. The population was characterized by an asymmetrical distribution of reproductive success; behaviorally dominant males produced 176 of 186 (95%) of the offspring in 44 social groups analyzed, and alpha females produced 185 of 186 (99.5%). We evaluated models of reproductive skew by examining genetic and demographic correlates of reproduction by␣subordinates. Subordinate (beta) males that sired young were more likely to be recent dispersers from their natal groups or members of newly formed groups than betas that did not reproduce. Breeding beta males had spent smaller proportions of their lives with the current alpha male and female as alphas than had beta males that did not sire young. One consequence of the linkage of dispersal with breeding in newly formed, nonnatal groups is that beta males that sired young had significantly lower genetic similarity to the alpha males in their groups (based on band-sharing coefficients using multilocus minisatellite DNA fingerprinting) than those that did not sire young. This pattern may occur generally in species in which group membership accrues both through nondispersal of young (forming groups of relatives) as well as through dispersal involving coalitions that sometimes include nonrelatives. Received: 22 July 1997 / Accepted after revision: 5 February 1998  相似文献   
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