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991.
The current status and future issues in human evacuation from ships   总被引:2,自引:0,他引:2  
The International Maritime Organization (IMO) developed guidelines in May 1999 for the evacuation analysis of Ro-Ro passenger ships to prevent loss of life in maritime accidents. However, IMO considered these guidelines only as an interim measure and allocated 3 years for their improvement and further development as very limited experience and data were available. In this paper, the requirements of the IMO and current research regarding ship evacuation are reviewed. In addition, applicable evacuation models are presented as well as several experimental methods of obtaining the data of human behavior in regard to listing and the dynamic effect of waves on a ship are evaluated. Recommendations on further issues are discussed at the end.  相似文献   
992.
ABSTRACT. Water development planning has virtually since its beginnings over one hundred fifty years ago utilized a variety of devices for involving segments of the public. But a new insistence for increased public participation, particularly at the Federal level, has stimulated re-examination of objectives and methods for relating water planning to citizen interests and preferences. Involved is partly a recommitment to democratic symbols, partly a recognition that segments of society have been overlooked, and partly a reaction to the pressures of confrontation and demonstration. The rhetoric and polemics of participation have often implied a kind of “town-meeting” process of decision, difficult at best in a nation of 200 million. In water planning more emphasis has been placed on listening to citizens, which has meant providing opportunities for influentials to express their views and preferences. A more adequate approach would seem to require identification of all who are significantly affected by plans and proposals (even though they may not perceive then-interest). But gaining greater participation does not make the planning job easier. It may increase tension and conflict; it may require difficult choices; and it can alter existing power relationships and generate changes with considerable consequences for the agency and its programs.  相似文献   
993.
ABSTRACT This paper is concerned with the portion of harbor improvement planning which identifies the refuge and transient service needs at points along Lake Michigan. The travel behavior model developed to predict this use is sensitive to five criteria: boater characteristics which influence travel behavior; entry rates into the Lake from each access site; site characteristics; weather conditions; and planning parameters. The information provided by this computer model includes: the number of boaters demanding a given access point at a given time; the length of stay at that point; the probability of travel to specific access sites in given amounts of time; and those facilities used during a specified time period. The simulation modelling boat movement consists of two parts; a traffic generation routine and an activity simulation. The former schedules the entry of boats into the Lake from each site and the latter establishes the probabilistic movement of boats on the Lake. This simulation of interport movements and port activities enables the planner to investigate some impacts of alternative small boat harbor development plans.  相似文献   
994.
林火行为预测预报专家系统   总被引:3,自引:0,他引:3  
在针对我国大兴安岭林区典型可燃物进行实验的基础上,参考美国北方林火实验室编制的BEHAVE程序中的数学模型,提出了一整套估算森林地表火火行为特征量的表达式。在此基础上,通过交互式窗口技术、字符型汉字技术和专家系统原理,建立了“林火行为预测预报专家系统”。该系统在输入现场可燃物分布特性参数及相应的地形条件和气象条件后,即能迅速预测火蔓延过程中不同时间段的火行为特征量的值。与野外试验的结果对比表明,预测的结果是合理、可靠的。  相似文献   
995.
Artificial manipulations of habitat, such as those that incorporate adding nesting boxes or platforms for birds, often enhance the breeding success of threatened animals. However, such alterations are likely to have unintended behavioral and ecological effects that might negatively impact the target species or others in its community. We conducted a controlled study to investigate the effect of artificial nesting platforms on aggressive behavior and reproductive success of male common loons (Gavia immer). Males residing on territories to which platforms were added produced longer territorial "yodels" (reflecting willingness to escalate a contest), experienced increased levels of confrontation and aggression with territorial intruders, and experienced increased rates of territorial displacement by intruders. Surprisingly, males of treatment territories also experienced lower productivity. Therefore, in addition to providing novel empirical support of sequential assessment models of animal contests that predict contest escalation with increasing resource quality, this study is one of a few to show that tools used to mitigate habitat loss can negatively impact reproductive fitness in a threatened species.  相似文献   
996.
Most small-colony termites live confined within a single piece of wood on which they feed and do not possess permanent workers: Tasks are done by developmentally flexible immatures (pseudergates). By contrast, large-colony termites possess a specialized (true) worker caste and forage outside their nest for food. To shed light on possible transitional steps between these contrasting patterns of social organization, we studied an atypical Rhinotermitidae, Prorhinotermes inopinatus. In this species, despite the absence of a true worker caste, soldiers, pseudergates, and neotenic reproductives may leave the nest and explore their surroundings. Although evidence presented in this study indicates that termites recognize unknown areas, there is no directional recruitment toward them. The discovery of a food source, i.e., a piece of wood, is followed by the establishment of a long-lasting trail between the nest and the food source. A large fraction of the colony, including neotenic reproductives, ultimately migrates into the piece of wood. Our results thus demonstrate that multiple features of external foraging behavior can evolve independently of the existence of a true worker caste in termites. We suggest that large colonies with true workers, like those of most Rhinotermitidae, may easily have evolved from a Prorhinotermes-like pattern if submitted to increasing selective pressures for worker efficiency in a stable environment.  相似文献   
997.
The high concentration of heavy metal (Cu, Cr, Zn, Pb) in tannery sludge causes severe heavy metal emissions in the process of incineration. In the present investigation, the tannery sludge was treated with 85% phosphoric acid before the incineration process in the tube furnace to control the heavy metal emissions. The thermal behavior and heavy metal vaporization of pre-treated tannery sludge were investigated, and X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis were also implemente...  相似文献   
998.
多溴联苯醚及其环境行为   总被引:7,自引:4,他引:3  
多溴联苯醚(PBDEs)在环境中的浓度快速增长,在各种生物体和人体中也发现了PBDEs的存在,因此已经成为了全球性的环境污染物,是目前研究的一大热点。文章介绍了PBDEs的物理化学性质、分析方法、在环境中的分布归趋和控制措施,着重介绍了水环境中PBDEs的分布和归趋。  相似文献   
999.
水环境中药物污染及迁移转化行为研究进展   总被引:5,自引:1,他引:4  
药物在人体健康和畜牧业生产中起到了积极的作用。但是未被完全吸收、利用的药物或其代谢物将通过尿液、粪便排泄等途径进入水体,而污水处理厂现有处理技术对其不能有效地去除。虽然药物在水体中的半衰期较短,但是其大量、频繁的使用,仍有可能形成"假性持久性"污染。近年来,在地表水、地下水、饮用水、污泥、土壤、水生物体内等环境介质中都报道有检测到不同浓度水平的药物,其对生态环境和人类健康的影响已引起国际社会广泛关注。欧美一些国家对水环境中药物做了较深入的研究,而我国相关研究报道较少。文章对水环境中药物的来源、污染现状及迁移转化行为等研究进展作了综合分析和讨论,为我国开展相关研究及建立水环境中药物污染的生态风险评价提供参考。  相似文献   
1000.
Introduction: Construction sites exhibit unique hazardous characteristics. Hence, investigating the causes of fatal and nonfatal accidents is extremely important to promote safety on construction sites. Literature shows a risk perception (RP) scale for construction workers; to expand the existing research, this study aims to identify risky scenarios for assessing the RP of Thai construction workers, with the goal of reducing workplace incidents. Method: The scale development process consists of four phases. Item development was also performed, followed by factor analysis. Reliability and validity assessments were finalized in the process. A survey of 500 construction workers in Thailand was conducted to investigate risky scenarios. Through the process, a total of 17 items remained in the final RP scale, and the reliability and validity of these items were confirmed. Results: The RP scale was affirmed to have four dimensions (probability, severity, worry, and unsafe). These dimensions of workers’ RP were negatively correlated with the workers’ risk-taking behaviors. This study further showed that participants with a high level of affective RP were more likely to have a high level of cognitive RP. Hence, those with a high level of RP tended to be involved in fewer risk-taking behaviors. Practical Applications: The final version of the scale was reliable and valid in determining the RP and risk-taking behaviors of construction workers in Thailand.  相似文献   
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