331 research outputs found

    The Arctic Climate System, by Roger Barry and Mark Serreze

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    Modelling Dynamics of Valley Glaciers

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    Angle of Attack Equipment in General Aviation Operations

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    The Federal Aviation Administration (FAA) in conjunction with the general aviation (GA) industry formed the General Aviation Joint Steering Committee (GAJSC) with the goal to improve overall general aviation safety. The GAJSC tasked their technical division, the Safety Analysis Team (SAT), with identifying safety issues present within GA. Upon review of fatal GA accidents between 2001 and 2010, it was concluded that over half of the fatal accidents were a result of loss of control inflight, or LOC-I. A Loss of Control Working Group (LOCWG) was formed between the FAA and the GA industry to research and recommend safety improvements. One of the recommended safety improvements offered is to consider the use of Angle of Attack Indicators in GA aircraft. This project is being conducted by the Partnership to Enhance General Aviation Safety, Accessibility and Sustainability (PEGASAS), an FAA Center of Excellence

    Semi-autonomous vehicles as a cognitive assistive device for older adults

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    Losing the capacity to drive due to age-related cognitive decline can have a detrimental impact on the daily life functioning of older adults living alone and in remote areas. Semi-autonomous vehicles (SAVs) could have the potential to preserve driving independence of this population with high health needs. This paper explores if SAVs could be used as a cognitive assistive device for older aging drivers with cognitive challenges. We illustrate the impact of age-related changes of cognitive functions on driving capacity. Furthermore, following an overview on the current state of SAVs, we propose a model for connecting cognitive health needs of older drivers to SAVs. The model demonstrates the connections between cognitive changes experienced by aging drivers, their impact on actual driving, car sensors' features, and vehicle automation. Finally, we present challenges that should be considered when using the constantly changing smart vehicle technology, adapting it to aging drivers and vice versa. This paper sheds light on age-related cognitive characteristics that should be considered when developing future SAVs manufacturing policies which may potentially help decrease the impact of cognitive change on older adult drivers

    Problems with Sleep Do Not Predict Self-Reported Driving Factors and Perception in Older Drivers: Evidences from the Candrive II Prospective Cohort

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    Given that sleep problems and serious motor vehicle collisions are increasingly prevalent in older adults, even minor drowsiness could potentially contribute to driving patterns in older drivers. To date, it is unknown whether less serious problems with sleep influence driving frequency and ability in older adults. We investigated the influence of everyday sleep disturbances on driving practices and driver perceptions in a large cohort of healthy older drivers. Selfreported measures of sleep problems were used to investigate the influence of sleep disturbance on self-reported driving practices and perceived driving abilities. On two measures of self-reported driving outcomes, participants with problems with rated themselves more poorly. However, this relationship disappeared when health and demographic variables were entered prior in hierarchical regression analyses. Our results show that the relationship between sleep problems, driving frequency and perceived abilities is better explained by mediating demographic, health, and cognitive factors

    An ethical framework for cardiac report cards: a qualitative study

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    BACKGROUND: The recent proliferation of health care report cards, especially in cardiac care, has occurred in the absence of an ethical framework to guide in their development and implementation. An ethical framework is a consistent and comprehensive theoretical foundation in ethics, and is formed by integrating ethical theories, relevant literature, and other critical information (such as the views of stakeholders). An ethical framework in the context of cardiac care provides guidance for developing cardiac report cards (CRCs) that are relevant and legitimate to all stakeholders. The purpose of this study is to develop an ethical framework for CRCs. METHODS: Delphi technique – 13 panelists: 2 administrators, 2 cardiac nurses, 5 cardiac patients, 2 cardiologists, 1 member of the media, and 1 outcomes researcher. Panelists' views regarding the ethics of CRCs were analyzed and organized into themes. RESULTS: We have organized panelists' views into ten principles that emerged from the data: 1) improving quality of care, 2) informed understanding, 3) public accountability, 4) transparency, 5) equity, 6) access to information 7) quality of information, 8) multi-stakeholder collaboration, 9) legitimacy, and 10) evaluation and continuous quality improvement. CONCLUSION: We have developed a framework to guide the development and dissemination of CRCs. This ethical framework can provide necessary guidance for those generating CRCs and may help them avoid a number of difficult issues associated with existing ones

    High Temperature Proton Exchange Membranes With Enhanced Proton Conductivities At Low Humidity and High Temperature Based On Polymer Blends and Block Copolymers of Poly(1,3-Cyclohexadiene) and Poly(ethylene Glycol)

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    Hot (at 120 °C) and dry (20% relative humidity) operating conditions benefit fuel cell designs based on proton exchange membranes (PEMs) and hydrogen due to simplified system design and increasing tolerance to fuel impurities. Presented are preparation, partial characterization, and multi-scale modeling of such PEMs based on cross-linked, sulfonated poly(1,3-cyclohexadiene) (xsPCHD) blends and block copolymers with poly(ethylene glycol) (PEG). These low cost materials have proton conductivities 18 times that of current industry standard Nafion at hot, dry operating conditions. Among the membranes studied, the blend xsPCHD-PEG PEM displayed the highest proton conductivity, which exhibits a morphology with higher connectivity of the hydrophilic domain throughout the membrane. Simulation and modeling provide a molecular level understanding of distribution of PEG within this hydrophilic domain and its relation to proton conductivities. This study demonstrates enhancement of proton conductivity at high temperature and low relative humidity by incorporation of PEG and optimized sulfonation conditions
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