38 research outputs found

    Advancing self-escape training : a needs analysis based on the National Academy of Sciences report "improving self-escape from underground coal mines."

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    "This report summarizes a needs analysis and actions taken by NIOSH based on the National Academy of Sciences recommendations specific to advancing self-escape training, with an emphasis on preparing rank-and-file mineworkers for self-escape. This report also provides the foundation for the practical guidance offered in its sister publication, the NIOSH Information Circular (IC) "Self-escape Core Competency Profile: Guidance for Improving Underground Coal Miners' Self-escape Competency" [NIOSH 2023], which offers an evidence-based self-escape competency framework derived from the results of this work." - NIOSHTIC-2NIOSHTIC no. 20067688Suggested citation: NIOSH [2023]. Advancing self-escape training: a needs analysis based on the National Academy of Sciences report, \u201cImproving Self-escape from Underground Coal Mines.\u201d By Hoebbel CL, Bellanca JL, Ryan ME, Brnich MJ. Pittsburgh PA: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 2023-134, https://doi.org/10.26616/NIOSHPUB2023134

    Several approaches for the traveling salesman problem

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    We characterize both approaches, mldp and k-mldp, with several methodologies; both a linear and a non-linear mathematical formulation are proposed. Additionally, the design and implementation of an exact methodology to solve both linear formulations is implemented and with it we obtained exact results. Due to the large computation time these formulations take to be solved with the exact methodology proposed, we analyse the complexity each of these approaches and show that both problems are NP-hard. As both problems are NP-hard, we propose three metaheuristic methods to obtain solutions in shorter computation time. Our solution methods are population based metaheuristics which exploit the structure of both problems and give good quality solutions by introducing novel local search procedures which are able to explore more efficiently their search space and to obtain good quality solutions in shorter computation time. Our main contribution is the study and characterization of a bi-objective problematic involving the minimization of two objectives: an economic one which aims to minimize the total travel distance, and a service-quality objective which aims to minimize of the waiting time of the clients to be visited. With this combination of objectives, we aim to characterize the inclusion of the client in the decision-making process to introduce service-quality decisions alongside a classic routing objective.This doctoral dissertation studies and characterizes of a combination of objectives with several logistic applications. This combination aims to pursue not only a company benefit but a benefit to the clients waiting to obtain a service or a product. In classic routing theory, an economic approach is widely studied: the minimization of traveled distance and cost spent to perform the visiting is an economic objective. This dissertation aims to the inclusion of the client in the decision-making process to bring out a certain level of satisfaction in the client set when performing an action. We part from having a set of clients demanding a service to a certain company. Several assumptions are made: when visiting a client, an agent must leave from a known depot and come back to it at the end of the tour assigned to it. All travel times among the clients and the depot are known, as well as all service times on each client. This is to say, the agent knows how long it will take to reach a client and to perform the requested service in the client location. The company is interested in improving two characteristics: an economic objective as well as a servicequality objective by minimizing the total travel distance of the agent while also minimizing the total waiting time of the clients. We study two main approaches: the first one is to fulfill the visits assuming there is a single uncapacitated vehicle, this is to say that such vehicle has infinite capacity to attend all clients. The second one is to fulfill the visits with a fleet of k-uncapacitated vehicles, all of them restricted to an strict constraint of being active and having at least one client to visit. We denominate the single-vehicle approach the minimum latency-distance problem (mldp), and the k-sized fleet the k-minimum latency-distance problem (k-mldp). As previously stated, this company has two options: to fulfil the visits with a single-vehicle or with a fixed-size fleet of k agents to perform the visits

    INTERDEPENDENT INFRASTRUCTURE RESILIENCE IN THE U.S. VIRGIN ISLANDS: PRELIMINARY ASSESSMENT

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    Prepared for: Federal Emergency Management AgencyThe U.S. Virgin Islands (USVI) is a territory comprised of three main islands—Saint Croix, Saint John, and Saint Thomas—and a number of smaller surrounding islands, located in the Leeward Islands of the Lesser Antilles approximately 40 miles east of Puerto Rico and over 1,100 miles from Miami, Florida. In September 2017, two Category-5 hurricanes made landfall within a two-week period and collectively devastated the homes, businesses, and infrastructure throughout the Territory.This technical report (1) explains the structure, function, and tensions associated with energy, water, transportation, and communication infrastructure that were chronic problems prior to the hurricanes; (2) documents hurricane response, recovery, and mitigation activities for these infrastructure systems after the hurricanes; and (3) provides concrete approaches to overcome potential barriers to resilience (where they exist) and open questions for research (where they do not yet exist).Federal Emergency Management AgencyFederal Emergency Management AgencyApproved for public release; distribution is unlimited

    Contested Deployment

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    As indicated in the 2018 National Defense Strategy and evolving Multi-Domain Operations doctrine, the assumption the homeland will provide a secure space for mobilization and deployment is no longer valid. This integrated research project goes beyond affirming this assumption and contributes to efforts to mitigate the concerns a contested deployment entails. Following the introductory chapter, Chapter 2, “Army Deployments in a Contested Homeland: A Framework for Protection,” explores how current coordination and cooperation mechanisms between the DoD and state and local government may need realignment, with civil authorities preparing themselves to support military mobilization. Chapter 3, “Strategic Seaports and National Defense in a Contested Environment,” examines the 22 strategic seaports across the United States, identifying issues with throughput, structural integrity, security, readiness, funding, and authorities. Chapter 4, “Single Point of Failure,” identifies how strict adherence to a business efficiency model for munition production and distribution may jeopardize the successful employment of military forces. Chapter 5, “The Interstate Highway System: Reinvestment Needed before a Contested Deployment,” provides the status of the deteriorating road network and explains how associated vulnerabilities could be exploited by an adversary. The two appendices provide points for consideration on cyberattacks and defense and the impacts a full mobilization of reserve forces would have on the homeland.https://press.armywarcollege.edu/monographs/1944/thumbnail.jp

    Disasters as Usual:The Public Life of Recurring Floods in Dresden

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    Safety and Reliability - Safe Societies in a Changing World

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    The contributions cover a wide range of methodologies and application areas for safety and reliability that contribute to safe societies in a changing world. These methodologies and applications include: - foundations of risk and reliability assessment and management - mathematical methods in reliability and safety - risk assessment - risk management - system reliability - uncertainty analysis - digitalization and big data - prognostics and system health management - occupational safety - accident and incident modeling - maintenance modeling and applications - simulation for safety and reliability analysis - dynamic risk and barrier management - organizational factors and safety culture - human factors and human reliability - resilience engineering - structural reliability - natural hazards - security - economic analysis in risk managemen

    Disruptive Technologies with Applications in Airline & Marine and Defense Industries

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    Disruptive Technologies With Applications in Airline, Marine, Defense Industries is our fifth textbook in a series covering the world of Unmanned Vehicle Systems Applications & Operations On Air, Sea, and Land. The authors have expanded their purview beyond UAS / CUAS / UUV systems that we have written extensively about in our previous four textbooks. Our new title shows our concern for the emergence of Disruptive Technologies and how they apply to the Airline, Marine and Defense industries. Emerging technologies are technologies whose development, practical applications, or both are still largely unrealized, such that they are figuratively emerging into prominence from a background of nonexistence or obscurity. A Disruptive technology is one that displaces an established technology and shakes up the industry or a ground-breaking product that creates a completely new industry.That is what our book is about. The authors think we have found technology trends that will replace the status quo or disrupt the conventional technology paradigms.The authors have collaborated to write some explosive chapters in Book 5:Advances in Automation & Human Machine Interface; Social Media as a Battleground in Information Warfare (IW); Robust cyber-security alterative / replacement for the popular Blockchain Algorithm and a clean solution for Ransomware; Advanced sensor technologies that are used by UUVs for munitions characterization, assessment, and classification and counter hostile use of UUVs against U.S. capital assets in the South China Seas. Challenged the status quo and debunked the climate change fraud with verifiable facts; Explodes our minds with nightmare technologies that if they come to fruition may do more harm than good; Propulsion and Fuels: Disruptive Technologies for Submersible Craft Including UUVs; Challenge the ammunition industry by grassroots use of recycled metals; Changing landscape of UAS regulations and drone privacy; and finally, Detailing Bioterrorism Risks, Biodefense, Biological Threat Agents, and the need for advanced sensors to detect these attacks.https://newprairiepress.org/ebooks/1038/thumbnail.jp
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