1,248 research outputs found

    Flight investigation of cockpit-displayed traffic information utilizing coded symbology in an advanced operational environment

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    Traffic symbology was encoded to provide additional information concerning the traffic, which was displayed on the pilot's electronic horizontal situation indicators (EHSI). A research airplane representing an advanced operational environment was used to assess the benefit of coded traffic symbology in a realistic work-load environment. Traffic scenarios, involving both conflict-free and conflict situations, were employed. Subjective pilot commentary was obtained through the use of a questionnaire and extensive pilot debriefings. These results grouped conveniently under two categories: display factors and task performance. A major item under the display factor category was the problem of display clutter. The primary contributors to clutter were the use of large map-scale factors, the use of traffic data blocks, and the presentation of more than a few airplanes. In terms of task performance, the cockpit-displayed traffic information was found to provide excellent overall situation awareness. Additionally, mile separation prescribed during these tests

    Influence of display and control compatibility on pilot-induced oscillations

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    The differences in techniques used by seven pilots to acquire information from an advanced display for instrument approaches to and landings on a runway were investigated. A fixed base simulator programmed with dynamics resembling the terminal configured vehicle (TCV) was studied. It is shown that the seven pilots can be divided into two groups which used the display with distinctly different strategies for controlling the airplane. A related pattern of performance differences resulted. It is found that pilots who primarily use raw flight path information experience longitudinal oscillations while pilots using attitude information did not

    Clinical Profile and Disability Levels of Younger vs. Older TKR and THR Patients in a National Research Consortium

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    Introduction: A growing number of patients under 65 years old undergo total knee replacement (TKR) and total hip replacement (THR).1 This trend has raised concerns that younger patients may receive surgery prematurely. We examined demographic and clinical factors in younger versus older patients in a national sample of THR and THR patients. Methods: Patients undergoing primary TKR and THR from 7/1/11 through 12/03/12 were identified from a national research consortium that gathers demographics, comorbid conditions (Charlson Comorbidity Index), Short Form 36 Physical Component Score (PCS) and Mental Component Score (MCS), burden of musculoskeletal disease using the Knee injury and Osteoarthritis Outcome Score (KOOS) or the Hip injury and Osteoarthritis Outcome Score (HOOS) and the Oswestry Low Back Pain Disability Questionnaire. Descriptive statistics were performed. Results: TKR patients included 1326 younger ( Conclusion: Younger patients have fewer medical illnesses at the time of TKR or THR, but have greater functional impairment and higher rates of obesity and smoking as well as lower mental health scores

    Trouble in Paradise - A disabled person's right to the satisfaction of a self-defined need:Some conceptual and practical problems

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    This paper questions the usefulness of the rights-based approach to ameliorating the social situation of disabled people in Britain and advances two criticisms. First, that rights and self-de? ned needs have been under-theorised by disability theorists to the extent that they have insuf? ciently appreciated the problems that these approaches pose. The paper suggests that rights to appropriate resources to satisfy self-de? ned needs will generate vast numbers of competing rights claims and that the resulting tendency of rights to con? ict has been under-appreciated. Secondly, that there has been little consideration of how these con? icts might be reconciled. The ? rst two sections of the paper look at the concepts of ascribed and self-de? ned needs, respectively, whilst the ? nal one looks at some of the problems of the rights approach and some of the dif? culties of making self-de? ned need the basis of rights claims

    Psychometric Development of the Research and Knowledge Scale

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    BACKGROUND: Many research participants are misinformed about research terms, procedures, and goals; however, no validated instruments exist to assess individual\u27s comprehension of health-related research information. We propose research literacy as a concept that incorporates understanding about the purpose and nature of research. OBJECTIVES: We developed the Research and Knowledge Scale (RaKS) to measure research literacy in a culturally, literacy-sensitive manner. We describe its development and psychometric properties. RESEARCH DESIGN: Qualitative methods were used to assess perspectives of research participants and researchers. Literature and informed consent reviews were conducted to develop initial items. These data were used to develop initial domains and items of the RaKS, and expert panel reviews and cognitive pretesting were done to refine the scale. We conducted psychometric analyses to evaluate the scale. SUBJECTS: The cross-sectional survey was administered to a purposive community-based sample (n=430) using a Web-based data collection system and paper. MEASURES: We did classic theory testing on individual items and assessed test-retest reliability and Kuder-Richardson-20 for internal consistency. We conducted exploratory factor analysis and analysis of variance to assess differences in mean research literacy scores in sociodemographic subgroups. RESULTS: The RaKS is comprised of 16 items, with a Kuder-Richardson-20 estimate of 0.81 and test-retest reliability 0.84. There were differences in mean scale scores by race/ethnicity, age, education, income, and health literacy (all P \u3c 0.01). CONCLUSIONS: This study provides preliminary evidence for the reliability and validity of the RaKS. This scale can be used to measure research participants\u27 understanding about health-related research processes and identify areas to improve informed decision-making about research participation

    Handling qualities of a wide-body transport airplane utilizing Pitch Active Control Systems (PACS) for relaxed static stability application

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    Piloted simulation studies have been conducted to evaluate the effectiveness of two pitch active control systems (PACS) on the flying qualities of a wide-body transport airplane when operating at negative static margins. These two pitch active control systems consisted of a simple 'near-term' PACS and a more complex 'advanced' PACS. Eight different flight conditions, representing the entire flight envelope, were evaluated with emphasis on the cruise flight conditions. These studies were made utilizing the Langley Visual/Motion Simulator (VMS) which has six degrees of freedom. The simulation tests indicated that (1) the flying qualities of the baseline aircraft (PACS off) for the cruise and other high-speed flight conditions were unacceptable at center-of-gravity positions aft of the neutral static stability point; (2) within the linear static stability flight envelope, the near-term PACS provided acceptable flying qualities for static stabilty margins to -3 percent; and (3) with the advanced PACS operative, the flying qualities were demonstrated to be good (satisfactory to very acceptable) for static stabilty margins to -20 percent

    The Biodiversity Heritage Library : advancing metadata practices in a collaborative digital library

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    Author Posting. © Taylor & Francis, 2010. This article is posted here by permission of Taylor & Francis for personal use, not for redistribution. The definitive version was published in Journal of Library Metadata 10 (2010): 136-155, doi:10.1080/19386389.2010.506400.The Biodiversity Heritage Library is an open access digital library of taxonomic literature, forming a single point of access to this collection for use by a worldwide audience of professional taxonomists, as well as “citizen scientists.” A successful mass-scanning digitization program, one that creates functional and findable digital objects, requires thoughtful metadata work flow that parallels the work flow of the physical items from shelf to scanner. This article examines the needs of users of taxonomic literature, specifically in relation to the transformation of traditional library material to digital form. It details the issues that arise in determining scanning priorities, avoiding duplication of scanning across the founding 12 natural history and botanical garden library collections, and the problems related to the complexity of serials, monographs, and series. Highlighted are the tools, procedures, and methodology for addressing the details of a mass-scanning operation. Specifically, keeping a steady flow of material, creation of page level metadata, and building services on top of data and metadata that meet the needs of the targeted communities. The replication of the BHL model across a number of related projects in China, Brazil, and Australia are documented as evidence of the success of the BHL mass-scanning project plan

    \u3cem\u3eTithonia diversifolia\u3c/em\u3e for Ruminant Nutrition

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    India and Brazil lead the world ranking of livestock enteric methane emissions (FAO 2006). According to FAO (2006), Brazil (9.6 Tg of CH4/year) is the highest emitter of methane from cattle, followed by India (8.6 Tg of CH4/year) and the USA (5.1 Tg of CH4/year). In livestock, methane (CH4) formed from enteric fermentation of carbohydrates is primarily responsible for the emissions in the sector. Regarding livestock methane emission, Delgado et al. (2012) evaluated 20 tree and shrub species using in vitro technique and demonstrated a reducing effect on the amount of methane when Tithonia diversifolia was compared with, for example, Cynodon nlemfuensis grass. Tithonia diversifolia belongs to the division - Sphermatophyta; class - Eudicotiledoneae; sub-class - Metaclamídeas; Order - Campanulate; Family - Asteraceae; Genre - Tithonia, and Species - Tithonia diversifolia (Hemsl.), Gray (Souza 2008). Tithonia diversifolia can be very useful in animal nutrition (Fig. 1) by increasing the protein content of animal diet at low cost (Murgueitio et al. 2010) as well as in the recovery of degraded soils for it grows in areas with low levels of fertility and has high ability to absorb phosphorus, even if it is unavailable to other forage species (Kwabiah et al. 2003). The objective of this study was to assess the nutritional qualities, including quantification of enteric methane generated during in vitro ruminal fermentation, of Tithonia diversifolia as an alternative forage for ruminant nutrition in the tropics

    Universality of the Gunn effect: self-sustained oscillations mediated by solitary waves

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    The Gunn effect consists of time-periodic oscillations of the current flowing through an external purely resistive circuit mediated by solitary wave dynamics of the electric field on an attached appropriate semiconductor. By means of a new asymptotic analysis, it is argued that Gunn-like behavior occurs in specific classes of model equations. As an illustration, an example related to the constrained Cahn-Allen equation is analyzed.Comment: 4 pages,3 Post-Script figure
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