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401.
Communication signals used in animal social interactions are frequently performed repetitively, but the function of this repetition is often not well understood. We examined the effects of signal repetition by investigating the behavior of worker honey bees that received differing numbers of vibration signals in established and newly founded colonies, which could use signal repetition differently to help adjust task allocations to the labor demands associated with the different stages of colony development. In both colony types, more than half of all monitored workers received more than one vibration signal, and approximately 12% received ≥5 signals during a given 20-min observation period. Vibrated recipients exhibited greater activity and task performance than same-age non-vibrated controls at all levels of signal activity. However, vibrated workers showed similar levels of task performance, movement rates, cell inspection rates, and trophallactic exchanges regardless of the number of signals received. Thus, the repeated performance of vibration signals on individual bees did not cause cumulative increases in the activity of certain workers, but rather may have functioned to maintain relatively constant levels of activity and task performance among groups of recipients. The established and newly founded colonies did not differ in the extent to which individual workers received the different numbers of vibration signals or in the levels of activity stimulated by repeated signals. Previous work has suggested that compared to established colonies, newly founded colonies have a greater number of vibrators that perform signals on a greater proportion of the workers they contact. Taken in concert, these results suggest that vibration signal repetition may help to adjust task allocations to the different stages of colony development by helping to maintain similar levels of activity among a greater total number of recipients, rather than by eliciting cumulative effects that cause certain recipients to work harder than others.  相似文献   
402.
It is now widely recognised that good communication between multi-disciplinary stakeholders is central to effective flood risk management. Recent developments in Geographical Information Systems, increased availability of accurate digital terrain models from remotely sensed data sources and improved graphical computer interfaces have made the outputs from computer models of flood inundation easily accessible to the stakeholder community. As a consequence, predictions from such models are now being used routinely as a means of communication between engineers and other stakeholders in flood risk management. This paper provides a review of the modelling methods most appropriate for flood risk communication. These are one-dimensional models which are suitable for simulating flood risk at a catchment or sub-catchment scale and appropriate for communicating the impact of strategic flood management decisions and two-dimensional models which can be applied across a range of scales but, are now being regularly applied at the relatively small scale, less than 10 km2, where they have the potential to inform and communicate disaster management decisions. The role of such models in communicating between modellers and non-modellers by providing a means for immediate visualisation of “the future” is discussed and illustrated by application to two case studies.  相似文献   
403.
With high profile flooding events and increasing risk and probable damages of flooding in the future flood risk management (FRM) in England and Wales has undergone substantial changes over the last decade. The contextual influences on flood risk communication in the areas of flood forecasting, warning and response, spatial planning and development control and flood insurance at a national level are investigated in this paper. Research is based on qualitative interviews with 21 representatives of key organisations and activities at a national level of FRM. Drawing on communication theory the research highlights the key contextual features at play: the characteristics of communication flow through organisations, the importance of policy as a communication tool informed and constrained by flood events, organisational agendas, communication approaches and the development of knowledge and technology. The paper describes the influence of clear policy guidance on activities in certain government FRM communication initiatives and the commercial imperative driving the insurance industry activities.  相似文献   
404.
《Environmental Hazards》2013,12(2):87-102
Mountain risk management is currently facing a scientifically driven, normative paradigm change towards risk governance, where communication and participation take on key roles. On the local level, hazard zone planning is a risk management tool to balance land-use developments and hazard processes, such as debris flows, avalanches, rock fall, mass movements or flooding. In this contribution, communication among stakeholders professionally involved in hazard zone planning (internal communication) is analysed by participant observation. Here, the quality of internal communication is seen both as an indicator and as a prerequisite for transition processes from risk management to risk governance. This case study of communication in hazard zone planning in the Autonomous Province of South Tyrol points out pitfalls and challenges in an advanced, spatial planning scheme. Based on the concept of social learning, it is argued that the transition towards governance of mountain risks requires fundamental changes in the underlying normative models, objectives, organizational understandings, structures and qualifications of the administrative bodies. Proposals for change are provided.  相似文献   
405.
Communicating risks has become a core ingredient in the regulatory functions of government, interest group advocacy, public health, and corporate relations. The channels of risk communication have grown in complexity along with the development and expansion of the Internet and the birth of personalized blogging. This paper discusses three stages in the development of risk communication as an area of study and research. It examines the way risk is framed in three channels of communication, newsprint, the Expanded Academic Index, and Google using the example of the controversial chemical perfluorooctanoic acid (PFOA). The paper concludes that the Internet, as illustrated by the Google search engine, has created more opportunities for citizen learning and expanded the breadth and channels of risk communication, while also providing new opportunities for stakeholders to influence the message. Democritization of information does not necessarily create greater concordance between the cultural and technical assessment of risk.  相似文献   
406.
丙烯腈装置安全预警及控制技术研究   总被引:1,自引:1,他引:0  
丙烯腈生产装置危险性极高,其主要设备大部分为压力容器、压力管道;其原料、中间产物、产品、副产品理化性质复杂,具有易燃、易爆、剧毒的特点。为提高丙烯腈生产企业管理水平,实现丙烯腈生产的远程监控、实时预警、过程控制和应急控制,为装置处于非正常工况下快速有序地实施风险控制,降低事故危害,减少事故损失提供技术支持,达到丙烯腈装置安全平稳生产的目的。在对某炼化企业丙烯腈生产装置风险分析的基础上,确定需监控的重点设备和关键参数,通过OPC通讯技术实时采集DCS操作参数数据并进行多参数趋势预警分析,建立起丙烯腈装置非正常工况下安全预警系统。系统主要包括关键参数安全预警分析、偏差标准操作处置程序、突发事件的应急评估、相关辅助信息等技术内容,涵盖安全保障的预防、预警、应急和处置的各个环节,实现了多参数实时监控、自动预警和应急辅助决策。  相似文献   
407.
When and how often to release information on television are important issues in crisis and emergency risk communication. There is a lot of crisis information, including warnings and news, to which people should have access, but most of it is not significantly urgent to interrupt the broadcasting of television programmes. Hence, the right timing for the release of crisis information should be selected based on the importance of the crisis and any associated communication requirements. Using recursive methods, this paper builds an audience coverage model of crisis information release. Based on 2007 Household Using TV (HUT) data for Hefei City, China, the optimal combination of broadcasting sequence (with frequencies between one and eight times) is obtained using the implicit enumeration method. The developed model is applicable to effective transmission of crisis information, with the aim of reducing interference with the normal television transmission process and decreasing the psychological effect on audiences. The same model can be employed for other purposes, such as news coverage and weather and road information.  相似文献   
408.
ABSTRACT: Global climate change is examined from the perspective of its relevancy and urgency as a public policy issue. Interpreting from literature specific to investigations into public awareness and concern, climate change is seen as a legitimate though less than urgent issue. The literature reveals that the general public holds surprising misconceptions about the processes contributing to climate change, including failure to grasp the fundamental connection to CO2. General ambivalence is also suggested from the results of two surveys conducted by The Groundwater Foundation. They first asked participants in a recent Groundwater Guardian Conference to rate levels of discussion and concern for water resources implications in the participants' communities. A second survey polled national water resource organizations about the extent climate change has been a focus of their educational, investigative, or advocacy efforts. The paper concludes by describing basic barriers to stimulating public response to climate change, which education about the issue should address, and by offering a model to educate and involve citizens based on the Groundwater Guardian program developed by the The Groundwater Foundation.  相似文献   
409.
Can animals, and especially cattle, be the subject ofmoral concern? Should we care about their well-being?Two competing ethical theories have addressed suchissues so far. A utilitarian theory which, inBentham's wake, extends moral consideration to everysentient being, and a theory of the rights orinterests of animals which follows Feinberg'sconceptions. This includes various positions rangingfrom the most radical (about animal liberation) tomore moderate ones (concerned with the well-being ofanimals). Notwithstanding their diversity, theseconceptions share some common flaws. First, as anextension of primarily anthropocentric theories (aboututility or rights) they still participate in the flawsof the original setting. Second, extending them tonon-human beings raises the problem of the borderwhich is to be drawn between what can be included inthe purview of moral consideration and what is leftoutside. Third, such theories are not able to distinguishbetween an ethics of wildlife and an ethics ofdomestic life, which too often leads to preposterousstatements. We would like to argue (i) that we should distinguishbetween environmental ethics (concerned withpopulations, species, biotic communities) and animalethics (where animals are taken into consideration individually);(ii) that individualist animal ethics are not relevantfor animal rearing; (iii) that animal rearing is a hierarchicalrelationship which rules are to be found in the fiction of a domesticcontract. Hence, we would like to construct a new conception ofthe ethics of the relation between men and the cattlethey breed based on the idea of a domestic contract.Our main assumption is Mary Midgleys's anthropologicalassumption, according to which human communities,since the Neolithic age, have always included variousanimals, so that relations of sociability have alwaysexisted between human beings and animals within thedomestic community (a mixed community). In order tospecify the hierarchical and non-egalitarian, butinclusive reciprocal obligations and relations insidesuch a community, we will elaborate on the notion ofa ``domestic contract'', an implicitly assumedidea traced back to Lucretius and whichwe will follow up to the physiocrats and Adam Smith.We will show that such an idea relies upon theassumption of communication between cattle farmer andanimals, of shared experience and exchanges betweenthe two parties. We will then show how modern factory,or battery animal farming, can be seen as unilaterallybreaking this domestic contract, forsaking ourduties towards domestic animals.  相似文献   
410.
Estimates of temporal trends in species’ occupancy are essential for conservation policy and planning, but limitations to the data and models often result in very high trend uncertainty. A critical source of uncertainty that degrades scientific credibility is that caused by disagreement among studies or models. Modelers are aware of this uncertainty but usually only partially estimate it and communicate it to decision makers. At the same time, there is growing awareness that full disclosure of uncertainty is critical for effective translation of science into policies and plans. But what are the most effective approaches to estimating uncertainty and communicating uncertainty to decision makers? We explored how alternative approaches to estimating and communicating uncertainty of species trends could affect decisions concerning conservation status of freshwater fishes. We used ensemble models to propagate trend uncertainty within and among models and communicated this uncertainty with categorical distributions of trend direction and magnitude. All approaches were designed to fit an established decision-making system used to assign species conservation status by the New Zealand government. Our results showed how approaches that failed to fully disclose uncertainty, while simplifying the information presented, could hamper species conservation or lead to ineffective decisions. We recommend an approach that was recently used effectively to communicate trend uncertainty to a panel responsible for setting the conservation status of New Zealand's freshwater fishes.  相似文献   
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