Assessing emergency preparedness in support of hazardous facility risk analyses: Application to siting a US hazardous waste incinerator

Increasing public resistance to hazardous materials transportation and facility operation has elicited a number of suggestions for improved risk communication, early community participation, and provision of incentives. Another potentially useful but hitherto neglected method of addressing local opposition to hazardous facility siting involves community emergency preparedness for a release of hazardous materials. This paper describes a procedure for analyzing local emergency preparedness in accordance with operational guidance from federal agencies in the United States and scientific principles derived from international research on disasters. This procedure identifies vulnerable areas of a community and assesses the capability of the community to take timely and effective protective actions including evacuation and sheltering in-place. Response capability is first assessed by verifying that local emergency response plans address the elements defined in state and federal guidance. Next, implementation analyses are conducted to determine whether the four critical functions of hazard detection and notification, protective action decision making, warning and public information, and protective action implementation can be accomplished with available resources under local conditions. These analyses indicate the degree to which formally designated emergency response activities of community agencies, as outlined by its Emergency Operations Plan (EOP), together with the informal social processes of emergency response known to operate in disasters, provide reasonable assurance of prompt and effective protective action by the public. Results of these analyses can provide administrative and judicial review processes with conclusions on the overall adequacy of local emergency preparedness, local emergency responders with suggestions as to which emergency preparedness improvements should be undertaken, and local residents with a better understanding of risk mitigation measures.     

Selection of protective action guides for nuclear incidents. EPA

In 1991 the Environmental Protection Agency (EPA) published its revised Manual of Protective Action Guides and Protective Actions for Nuclear Incidents. The protective action guides contained in the manual represent EPA's formal recommendations to Federal, State, and local emergency response officials for protecting public health and safety during a nuclear incident. These guides are expressed in terms of the projected dose at which action(s) should be taken to reduce or eliminate that dose. In determining the appropriate values for the protective action guides, the Agency considered the following four principles: (1) acute health effects should be avoided, (2) the risk of delayed health effects should be minimized, (3) the values should not be higher than justified by a cost-benefit analysis, and (4) the risk to health from implementing the protective action should not be greater than the risk from the dose avoided. This paper examines each of these principles and their application in the selection of the evacuation and sheltering protective action guides for the early, or immediate, phase of a nuclear incident.     

Planning for protective action decision making: evacuate or shelter-in-place

Protecting the public from an airborne hazardous chemical release requires that appropriate protective actions be selected quickly. When deciding whether to recommend evacuation or shelter-in-place, decision makers must weigh the interaction of numerous factors that characterize the release, the meteorological conditions, and the populations that may be affected. This article examines the components of the protective action decision process and describes steps that should be taken in a planning context to prepare for efficient decision making during an emergency. Methods of organizing information to facilitate decision making are identified, and a model useful for detailed analysis of specific emergency scenarios is described.     

An overview of protective action decision-making for a nuclear power plant emergency

Protection of the public in a nuclear power plant emergency requires decision-makers to balance the time requirements from two chains of events: the events associated with a radiological release and the events involved with the response to that release. The management of these events is distributed among personnel at the nuclear plant, in the local community, and in state and federal agencies. All of these parties must coordinate their response to the emergency to assure that timely and effective protective response can be made by the risk area population. This article describes the process by which protective action recommendations (PARs) are developed in nuclear power plant emergency exercises and provides recommendations from research on emergency response in other types of natural and technological hazards.     

Age-dependent potassium iodide effect on the thyroid irradiation by 131I and 133I in the nuclear emergency

The initial near-field exposure is primarily through inhalation in a nuclear emergency and the dominant contribution to the effective inhalation dose comes from radioiodine. Thyroid blockade by oral potassium iodide (KI) is efficient and practical for public in the nuclear emergency. Age-dependent radioprotective effect of KI on the thyroid irradiation by (131)I and (133)I has been derived using the simplified compartment model of iodine metabolism and WinSAAM program. Administration of KI within 2 h after (131)I and (133)I intake can block thyroid uptake significantly, yielding protective effect of 78.9% and 74.3%, respectively, for (131)I and (133)I for adults. The mean absorbed doses decrease with age, while protective effects of KI are similar for all age groups.     

Decision support in nuclear emergencies

In a nuclear emergency, protective actions such as evacuation, sheltering and food bans can be taken to mitigate the consequences of any release of radioactivity. Within the RODOS project, an evaluation framework has been developed to support the assessment of the costs and benefits of potential actions. In order to help the decision makers gain insight into the decision problem and clarify their preferences, guidance can be given in three stages. First, the search of feasible portfolios of protective actions is seen as a constraint satisfaction problem; only those portfolios that satisfy constraints depending on factors such as feasibility are worth further evaluation. Second, the portfolios are ranked based on their consequences and the preferences of the decision makers using either a multi-attribute value or utility function. Third, a natural language report explaining the ranking is produced to help the decision makers gain insight into the decision problem and refine the decision parameters. An intelligent decision system has been developed to demonstrate the feasibility of the framework.     

Emergency management in the early phase

An overview of response management in the early phase of an emergency at a nuclear installation is provided from a systems approach. This starts with the recognition of response goals, and using detailed analyses of threats, past experience, international law and principles, a response strategy is developed. The process is illustrated for the case of severe accidents at pressurized water reactors (PWRs) and identifies the need for and nature of: emergency classification based on plant conditions, notification, radiological monitoring and assessment strategies, operational criteria for implementing protective action decisions and management of public information. From the strategy detailed, functional and infrastructure requirements can be defined. The paper also presents some reflections on the key differences between response to emergencies arising from accidents and those arising from deliberate acts; on the preparedness and response capabilities of States, highlighting areas where generic improvements are needed and how best to achieve that.     

Protective action recommendations based upon plant conditions

Analyses conducted by the Nuclear Regulatory Commission (NRC) indicate that timely and effective protective action would be necessary to protect the public in a major nuclear power plant accident. Given the large amount of time required to implement an evacuation around most reactor sites, protective action recommendations (PARs) must be based upon specific plant indicators regarding the status of the core and systems that protect the core. This article describes the assumptions made, and the analyses conducted, by the NRC in developing its procedures for PARs based upon plant conditions.     

The social psychology of public response to warnings of a nuclear power plant accident

This article reviews the process of public response to warnings of an impending nuclear power plant emergency. Significant evidence exists to suggest that people engage in protective action in response to warnings based upon the substance and course through which emergency warning information is disseminated. The three basic components of a warning system are defined, and the elements of public response to warnings are summarized. Popular myths about public response to warnings are outlined and dispelled based upon current research verification. The conclusion provides an overview and synthesis of the warning response process.     

爆破漏斗形成过程的DDA模拟分析

对于块体等非连续介质在外力作用下运动或破坏规律的模拟,有限元(FEM)和离散元(DEM)法有一定的局限性,而非连续变形分析方法(DDA)更适用。本研究中,利用二维DDA对有、无节理面强度两种情况下一半无限域内球形药包爆炸时爆破漏斗的形成过程进行了动态模拟,并对模拟结果进行了分析和比较。结果表明,用DDA法模拟被节理分割的岩体在爆炸载荷作用下块体的运动规律具有独特的优越性,但它还不能模拟爆炸近区的特征。     

A Memory-efficient Simulation Method of Grover's Search Algorithm

Grover's search algorithm is one of the most significant quantum algorithms, which can obtain quadratic speedup of the extensive search problems. Since Grover's search algorithm cannot be implemented on a real quantum computer at present, its quantum simulation is regarded as an effective method to study the search performance. When simulating the Grover's algorithm, the storage space required is exponential, which makes it difficult to simulate the high-qubit Grover's algorithm. To this end, we deeply study the storage problem of probability amplitude, which is the core of the Grover simulation algorithm. We propose a novel memory-efficient method via amplitudes compression, and validate the effectiveness of the method by theoretical analysis and simulation experimentation. The results demonstrate that our compressed simulation search algorithm can help to save nearly 87.5% of the storage space than the uncompressed one. Thus under the same hardware conditions, our method can dramatically reduce the required computing nodes, and at the same time, it can simulate at least 3 qubits more than the uncompressed one. Particularly, our memory-efficient simulation method can also be used to simulate other quantum algorithms to effectively reduce the storage costs required in simulation.     

A GIS-based prediction and assessment system of off-site accident consequence for Guangdong nuclear power plant

GNARD (Guangdong Nuclear Accident Real-time Decision support system) is a decision support system for off-site emergency management in the event of an accidental release from the nuclear power plants located in Guangdong province, China. The system is capable of calculating wind field, concentrations of radionuclide in environmental media and radiation doses. It can also estimate the size of the area where protective actions should be taken and provide other information about population distribution and emergency facilities available in the area. Furthermore, the system can simulate and evaluate the effectiveness of countermeasures assumed and calculate averted doses by protective actions. All of the results can be shown and analysed on the platform of a geographical information system (GIS).     

Experiences in methods to involve key players in planning protective actions in the case of a nuclear accident

A widely used method in the planning of protective actions is to establish a stakeholder network to generate a comprehensive set of generic protective actions. The aim is to increase competence and build links for communication and coordination. The approach of this work was to systematically evaluate protective action strategies in the case of a nuclear accident. This was done in a way that the concerns and issues of all key players could be transparently and equally included in the decision taken. An approach called Facilitated Decision Analysis Workshop has been developed and tested. The work builds on case studies in which it was assumed that a hypothetical accident had led to a release of considerable amounts of radionuclides and, therefore, various types of countermeasures had to be considered. Six workshops were organised in the Nordic countries where the key players were represented, i.e. authorities, expert organisations, industry and agricultural producers.     

高精度星图模拟及有效性验证新方法

为在地面上进行星图模拟以测试星图识别算法和星敏感器性能,提出了一种新的高精度星图模拟方法。该方法利用截面圆和固定区域的性质,根据赤纬值求解赤经跨度来确定选星条件;将选出的导航星通过构建理想星敏感器模型,来求解它们在CCD面阵上的精确位置;根据位置信息,采用TFT液晶光阀,以实现高质量的星图模拟;利用星间角距和投影原理的性质来验证星图模拟的有效性。仿真实验结果表明,与现有星图模拟方法相比,此方法选星速度快,模拟实时性好,准确率达到98.8742%,位置精度达到1/50个像素。     

Research on key technologies of FEM simulation of temperature field in the process of quenching

In this paper, some key technologies of computing the quenching temperature field are given. According to the characteristics of quenching process, a new method of computing phase-transformation latent heat is presented to ensure the computation accuracy of temperature. The phase-transform latent heat is regarded as the internal heat source because it can result in the rise of temperature in the process of cooling. A new method of self-control and adaptive time-step is presented in this paper. This method can be used to compute the time-step according to maximum and minimum difference values of the temperature field between the previous simulating step and the current simulating step. A finite element method (FEM) software for evaluating the temperature and the phase-transformation is developed by using the methods presented in this paper, the lump parameters method and fine mesh method. The experimental results or analytical values of two cases are used to check the accuracy of FEM simulation. The comparisons show that the simulation results of FEM software are consistent with experimental results or analytical values.     

舰艇发射装置冲击输入设计方法研究

为提高舰艇发射装置抗冲击性能,分别采用静G法、动态设计分析方法和时域模拟法对其进行冲击响应计算。结果表明,静态G法和动态设计分析方法对应的冲击环境较弱,而时域模拟法可以提供更加严酷的冲击环境,对舰艇发射装置进行详细的冲击响应计算时有必要采用时域模拟法。在同一冲击载荷作用下,结构响应特性以横向响应为主,横向抗冲击设计不可忽视。所得结论对舰艇设备进行抗冲击设计有一定参考价值。     

MPP并行机上数亿粒子规模的分子动力学模拟

提出一种基于“块-单元-链表”数据结构和HSFC动态负载平衡的并行分子动力学算法,实现了大规模、非均匀分子动力学模拟的基于MPI的可扩展并行计算,以辅助物理学家实现具有实验意义的纳米级模拟。具体地,在某MPP并行机的240个CPU上,计算3．84亿(二维)和2．76亿(三维)个粒子规模的金属微喷射问题,均获得了209倍以上的加速比。     

基于结构相似性的图像质量评价方法

分析现有图像质量评价方法特点,针对基于失真敏感度的质量评价方法的局限性,提出了一种新的基于结构相似度的图像质量评价方法,从亮度、对比度、结构三个子方面得到一个总的相似性度量作为质量客观评价标准.该方法充分考虑了图像的结构信息和人类视觉的特性,从图像内容的理解功能出发,通过数学建模估算出人眼对图像质量的主观视觉感受,使结构相似性计算模型符合图像处理应用的本质.通过理论推导和算法验证,该方法可以为选择图像压缩算法和评价图像质量提供依据.将采用压缩算法SPIHT编解码后的图像与传统的峰值信噪比方法评价图像相比,实验表明,本文提出的算法是一种更为有效的图像质量评价方法.     

Effectiveness of expedient sheltering in place in a residence

The objective of this study was to evaluate the effectiveness of expedient sheltering in place in a residence for protection against airborne hazards, as outlined in the U.S. Department of Homeland Security (DHS) guidance to the public. An improved method was developed to determine the air flow rate for a shelter inside a house. Expedient sheltering measures (plastic sheeting and duct tape) were applied to a room inside a test house by participants who followed the DHS guidance. Measured air flow rates were used to determine protection factors for various scenarios. Protection factors were calculated for the house and shelter under various occupancy times, weather conditions, and outdoor exposure times for hazardous agents. Protection factors ranged from 1.3 to 539, depending on the conditions. Results indicate that proper sealing can make a substantial difference in the effectiveness of the shelter. Sheltering in place can be most beneficial if people enter shelters before the arrival of a cloud of hazardous agent, and people exit shelters as soon as the cloud passes over. However, sheltering in place can be detrimental if people enter or exit shelters too late. CO2 and O2 concentrations inside the shelter are not likely to reach dangerous levels under most scenarios, but concentrations could reach dangerous levels under certain conditions, and concentration levels could affect individuals with respiratory problems.