7,989 research outputs found

    Occupational cooling practices of emergency first responders in the United States: A survey

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    This is an accepted manuscript of an article published by Taylor & Francis in Temperature on 29/07/2018, available online: https://doi.org/10.1080/23328940.2018.1493907 The accepted version of the publication may differ from the final published version.© 2018 Informa UK Limited, trading as Taylor & Francis Group. Despite extensive documentation directed specifically toward mitigating thermal strain of first responders, we wished to ascertain the degree to which first responders applied cooling strategies, and what opinions are held by the various agencies/departments within the United States. An internet-based survey of first responders was distributed to the International Association of Fire Chiefs, International Association of Fire Firefighters, National Bomb Squad Advisory Board and the USA Interagency Board and their subsequent departments and branches. Individual first responder departments were questioned regarding the use of pre-, concurrent, post-cooling, types of methods employed, and/or reasons why they had not incorporated various methods in first responder deployment. Completed surveys were collected from 119 unique de-identified departments, including those working in law enforcement (29%), as firefighters (29%), EOD (28%) and HAZMAT technicians (15%). One-hundred and eighteen departments (99%) reported heat strain/illness to be a risk to employee safety during occupational duties. The percentage of departments with at least one case of heat illness in the previous year were as follows: fire (39%) HAZMAT (23%), EOD (20%) and law enforcement (18%). Post-cooling was the scheduled cooling method implemented the most (63%). Fire departments were significantly more likely to use post-cooling, as well as combine two types of scheduled cooling compared to other departments. Importantly, 25% of all departments surveyed provided no cooling whatsoever. The greatest barriers to personnel cooling were as follows–availability, cost, logistics, and knowledge. Our findings could aid in a better understanding of current practices and perceptions of heat illness and injury prevention in United States first responders. Abbreviations: EOD: explosive ordnance disposal; HAZMAT: hazardous materials.This project is financially supported by the United States Government through the United States Department of Defense (DOD).Published versio

    Advisory Algorithm for Scheduling Open Sectors, Operating Positions, and Workstations

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    Air traffic controller supervisors configure available sector, operating position, and work-station resources to safely and efficiently control air traffic in a region of airspace. In this paper, an algorithm for assisting supervisors with this task is described and demonstrated on two sample problem instances. The algorithm produces configuration schedule advisories that minimize a cost. The cost is a weighted sum of two competing costs: one penalizing mismatches between configurations and predicted air traffic demand and another penalizing the effort associated with changing configurations. The problem considered by the algorithm is a shortest path problem that is solved with a dynamic programming value iteration algorithm. The cost function contains numerous parameters. Default values for most of these are suggested based on descriptions of air traffic control procedures and subject-matter expert feedback. The parameter determining the relative importance of the two competing costs is tuned by comparing historical configurations with corresponding algorithm advisories. Two sample problem instances for which appropriate configuration advisories are obvious were designed to illustrate characteristics of the algorithm. Results demonstrate how the algorithm suggests advisories that appropriately utilize changes in airspace configurations and changes in the number of operating positions allocated to each open sector. The results also demonstrate how the advisories suggest appropriate times for configuration changes

    Dynamic structure selection and instabilities of driven Josephson lattice in high-temperature superconductors

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    We investigate the dynamics of the Josephson vortex lattice in layered high-Tc_{c} superconductors at high magnetic fields. Starting from coupled equations for superconducting phases and magnetic field we derive equations for the relative displacements [phase shifts] between the planar Josephson arrays in the layers. These equations reveal two families of steady-state solutions: lattices with constant phase shifts between neighboring layers, starting from zero for a rectangular configuration to π\pi for a triangular configuration, and double-periodic lattices. We find that the excess Josephson current is resonantly enhanced when the Josephson frequency matches the frequency of the plasma mode at the wave vector selected by the lattice structure. The regular lattices exhibit several kinds of instabilities. We find stability regions of the moving lattice in the plane lattice structure - Josephson frequency. A specific lattice structure at given velocity is selected uniquely by boundary conditions, which are determined by the reflection properties of electromagnetic waves generated by the moving lattice. With increase of velocity the moving configuration experiences several qualitative transformations. At small velocities the regular lattice is stable and the phase shift between neighboring layers smoothly decreases with increase of velocity, starting from π\pi for a static lattice. At the critical velocity the lattice becomes unstable. At even higher velocity a regular lattice is restored again with the phase shift smaller than π/2\pi/2. With increase of velocity, the structure evolves towards a rectangular configuration.Comment: 28 pages, 12 figures, submitted to Phys. Rev.

    Investigating the Heat Generation Efficiency of Electrically-Conductive Asphalt Mastic Using Infrared Thermal Imaging

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    One of the emerging technologies for producing sustainable ice-and snow-free pavements is the use of electrically-conductive surface courses, e.g., electrically-conductive asphalt concrete (ECAC) that can melt ice and snow through resistive heating. Modifying the mastic in asphalt concrete with electrically-conductive materials is a promising approach for producing high-quality ECAC. The objective of this study is to evaluate electrical conductivity and heat generation efficiency of electrically-conductive asphalt mastic (ECAM) specimens at a below-freezing temperature—simulating the harsh weather conditions in North America during the wintertime. To this end, asphalt mastic was electrically modified with carbon fiber (CF) at varying volume contents. The ECAM specimens were then powered by 60V AC during a time window of 10 minutes so that their heat generation capacity could be characterized through infrared thermography (IRT). Based on the resistivity measurements and thermal data analysis, the most reasonable CF content enabling rapid heat-generating ECAM was identified; this has future implications with respect to achieving efficient highway, bridge, and airport pavement operations during wintertime

    MARKETING ROLE IN ALTERING STRATEGIES TOCOLLABORATE IN SUSTAINABLE DEVELOPMENT

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    With the growing recognition of major environmental trends, marketers are reorganizing or regenerating their strategies and practices to meet the new challenges. The intent of this paper is to highlight new marketing strategic thinking, to accommodate for creative sustainable development. It introduces the importance of environment and sustainable development to the world around us. It defines a critical environmental problem and tries to find solutions from a marketing discipline. It tackles on latest marketing terminologies, such as consumerism, green marketing, ethical consumption, ecological concerns and green innovation and promotion. This paper reviews and analyzes three environmental trends, to determine their effects on marketing strategies interventions toward providing solutions to environmental problems opposing our globe today. The paper indicates that businesses can change and alter marketing strategies to protect the environment and consequently achieve creative sustainable development. We also note the essential role of learning organizations in the twenty first century. Successful strategies in prospect will need to be receptive and adaptive rather than permanent and rigid to accommodate the fact that customers are more market literate. Close to the end of the paper is a reflection of misusage of some companies with respect to corporate social responsibility, thus misleading the society by taking green marketing as propaganda for their advertizing and using marketing strategies to differentiate themselves rather than save the planet

    Estimating offsets for avian displacement effects of anthropogenic impacts

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    Biodiversity offsetting, or compensatory mitigation, is increasingly being used in temperate grassland ecosystems to compensate for unavoidable environmental damage from anthropogenic developments such as transportation infrastructure, urbanization, and energy development. Pursuit of energy independence in the United States will expand domestic energy production. Concurrent with this increased growth is increased disruption to wildlife habitats, including avian displacement from suitable breeding habitat. Recent studies at energy-extraction and energy-generation facilities have provided evidence for behavioral avoidance and thus reduced use of habitat by breeding waterfowl and grassland birds in the vicinity of energy infrastructure. To quantify and compensate for this loss in value of avian breeding habitat, it is necessary to determine a biologically based currency so that the sufficiency of offsets in terms of biological equivalent value can be obtained. We describe a method for quantifying the amount of habitat needed to provide equivalent biological value for avifauna displaced by energy and transportation infrastructure, based on the ability to define five metrics: impact distance, impact area, pre-impact density, percent displacement, and offset density. We calculate percent displacement values for breeding waterfowl and grassland birds and demonstrate the applicability of our avian-impact offset method using examples for wind and oil infrastructure. We also apply our method to an example in which the biological value of the offset habitat is similar to the impacted habitat, based on similarity in habitat type (e.g., native prairie), geographical location, land use, and landscape composition, as well as to an example in which the biological value of the offset habitat is dissimilar to the impacted habitat. We provide a worksheet that informs potential users how to apply our method to their specific developments and a framework for developing decision-support tools aimed at achieving landscape-level conservation goals

    Motivation for Air-Launch: Past, Present, and Future

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    Air-launch is defined as two or more air-vehicles joined and working together, that eventually separate in flight, and that have a combined performance greater than the sum of the individual parts. The use of the air-launch concept has taken many forms across civil, commercial, and military contexts throughout the history of aviation. Air-launch techniques have been applied for entertainment, movement of materiel and personnel, efficient execution of aeronautical research, increasing aircraft range, and enabling flexible and efficient launch of space vehicles. For each air-launch application identified in the paper, the motivation for that application is discussed

    Harmless? A hierarchical analysis of poppers use correlates among young gay and bisexual men

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    © 2019 Australasian Professional Society on Alcohol and other Drugs Introduction and Aims: Poppers (alkyl nitrites) are recreational substances commonly used during sexual activity. The current legal status of poppers is complex and wide-ranging bans are increasingly under discussion. Research has identified disproportionate levels of poppers use in sexual minority men. While research on poppers use among sexual minority men exists, little is known about poppers use patterns and correlations with psychosocial and other factors among gay and bisexual young men. Design and Methods: A cross-sectional survey was conducted with 836 Australian gay and bisexual young men aged 18 to 35 years. Descriptive statistics and hierarchical segmentation analyses were conducted to identify poppers use patterns, and correlates of recent poppers use (past 3 months) with personal characteristics, use of other substances, as well as mental and psychosocial health including minority stress, LGBT-community connectedness and participation. Results: High levels of lifetime (38%, n = 315) and recent (24%, n = 204) poppers use were reported. However, few participants reported dependency symptoms, risky consumption or problems arising from using poppers. The final model included three variables (visiting sex-on-premises venues, licensed LGBT venues, and using other substances) and predicted 85% (n = 174) of recent poppers use. No correlations with other concepts or characteristics could be identified. Conclusion: This analysis further supports the hypothesis that poppers may be substances with a comparably low-risk profile. A regulation of poppers with a harm reduction approach may present a valuable public health intervention

    Energy Technology Progress for Sustainable Development

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    Energy security is a fundamental part of a country`s national security. Access to affordable, environmentally sustainable energy is a stabilizing force and is in the world community`s best interest. The current global energy situation however is not sustainable and has many complicating factors. The primary goal for government energy policy should be to provide stability and predictability to the market. This paper differentiates between short-term and long-term issues and argues that although the options for addressing the short-term issues are limited, there is an opportunity to alter the course of long-term energy stability and predictability through research and technology development. While reliance on foreign oil in the short term can be consistent with short-term energy security goals, there are sufficient long-term issues associated with fossil fuel use, in particular, as to require a long-term role for the federal government in funding research. The longer term issues fall into three categories. First, oil resources are finite and there is increasing world dependence on a limited number of suppliers. Second, the world demographics are changing dramatically and the emerging industrialized nations will have greater supply needs. Third, increasing attention to the environmental impacts of energy production and use will limit supply options. In addition to this global view, some of the changes occurring in the US domestic energy picture have implications that will encourage energy efficiency and new technology development. The paper concludes that technological innovation has provided a great benefit in the past and can continue to do so in the future if it is both channels toward a sustainable energy future and if it is committed to, and invested in, as a deliberate long-term policy option
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