7 research outputs found
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Vital area identification for U.S. Nuclear Regulatory Commission nuclear power reactor licensees and new reactor applicants.
U.S. Nuclear Regulatory Commission nuclear power plant licensees and new reactor applicants are required to provide protection of their plants against radiological sabotage, including the placement of vital equipment in vital areas. This document describes a systematic process for the identification of the minimum set of areas that must be designated as vital areas in order to ensure that all radiological sabotage scenarios are prevented. Vital area identification involves the use of logic models to systematically identify all of the malicious acts or combinations of malicious acts that could lead to radiological sabotage. The models available in the plant probabilistic risk assessment and other safety analyses provide a great deal of the information and basic model structure needed for the sabotage logic model. Once the sabotage logic model is developed, the events (or malicious acts) in the model are replaced with the areas in which the events can be accomplished. This sabotage area logic model is then analyzed to identify the target sets (combinations of areas the adversary must visit to cause radiological sabotage) and the candidate vital area sets (combinations of areas that must be protected against adversary access to prevent radiological sabotage). Any one of the candidate vital area sets can be selected for protection. Appropriate selection criteria will allow the licensee or new reactor applicant to minimize the impacts of vital area protection measures on plant safety, cost, operations, or other factors of concern
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Critical infrastructure systems of systems assessment methodology.
Assessing the risk of malevolent attacks against large-scale critical infrastructures requires modifications to existing methodologies that separately consider physical security and cyber security. This research has developed a risk assessment methodology that explicitly accounts for both physical and cyber security, while preserving the traditional security paradigm of detect, delay, and respond. This methodology also accounts for the condition that a facility may be able to recover from or mitigate the impact of a successful attack before serious consequences occur. The methodology uses evidence-based techniques (which are a generalization of probability theory) to evaluate the security posture of the cyber protection systems. Cyber threats are compared against cyber security posture using a category-based approach nested within a path-based analysis to determine the most vulnerable cyber attack path. The methodology summarizes the impact of a blended cyber/physical adversary attack in a conditional risk estimate where the consequence term is scaled by a ''willingness to pay'' avoidance approach
Distribution of Culex coronator in the USA
In 1920, Culex coronator was reported from San Benito, Texas, and later in Arizona, New Mexico, and Oklahoma. In 2005, this species was reported to be spreading across the southeastern USA. Now reported in 14 states, it has been found as far north as northern Oklahoma; Memphis, TN; and Suffolk, VA. The public health significance of Cx. coronator is not firmly established, even though it has been implicated as a potential vector of several arboviral diseases. This study aims to document additional Cx. coronator county-level records, to provide information about its continued expansion across the southern USA, and to provide a short research update into its vector potential. Data acquired through multistate collaborations and author collections resulted in 146 new county records from Alabama, Arkansas, Florida, Georgia, Louisiana, Mississippi, North Carolina, Oklahoma, South Carolina, and Texas. No new county records were presented for Arizona, New Mexico, Tennessee, or Virginia, which had previously reported this species. With these new data, this species has been documented in 386 counties in 14 states of the continental USA.Peer reviewedEntomology and Plant Patholog
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Development and Test Case Application of a Waste Minimization Project Evaluation Method
The authors have developed and applied a methodology to evaluate and prioritize proposed waste minimization activities affecting Department of Energy (DOE) programs. The approach provides a systematic and defensible method for selecting a set of waste minimization proposals that maximizes the benefits to DOE while maintaining costs within a specified budget. The report discusses the development of a structured set of evaluation criteria to characterize waste minimization issues; techniques for documenting the anticipated and potential costs, risks, and benefits of waste minimization proposals; and a method of translating disparate data into a figure of merit for each proposal. A test case demonstration of this prioritization approach was applied to proposals currently being considered at two DOE weapons production facilities. Recommendations are provided for combining this approach with the existing DOE proposal selection process. 9 refs., 9 figs., 3 tabs
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Development and Test Case Application of a Waste Minimization Project Evaluation Method
This paper describes a formal process for selecting, from a diverse set of proposed waste minimization activities, those activities that provide the greatest benefit to Department of Energy (DOE). A methodology for evaluating and prioritizing proposals was developed to illustrate how the selection process works and what types of data are required to characterize waste minimization activities. It is clearly impossible to remove all aspects of subjective judgment from the proposal selection process. With this important consideration in mind, the methodology presented is put forth to enhance, not replace, the traditional DOE decision-making process. 5 refs., 2 figs., 1 tab
Probing intermetallic coupling in dinuclear N-heterocyclic carbene ruthenium(II) complexes
A series of bimetallic N-heterocyclic carbene (NHC) ruthenium(II) complexes were synthesized, which comprise two [RuClā(cymene)(NHC)] units that are interlinked via the NHC nitrogens by alkyl chains of different length. Electrochemical characterization revealed two mutually dependent oxidation processes for the complex with a methylene linker, indicating moderate intramolecular electronic coupling of the two metal centers (class II system). The degree of coupling decreases rapidly upon increasing the number of CHā units in the linker and provides essentially decoupled class I species when propylene or butylene linkers are used. Electrochemical analyses combined with structural investigations suggest a through-bond electronic coupling. Replacement of the alkyl linker with a p-phenylene group afforded cyclometalated complexes, which were considerably less stable. The electronic coupling in the methylene-linked complex and the relatively robust NHCāruthenium bond may provide access to species that are switchable on the molecular scale