24,235 research outputs found

    Out-reach in-space technology experiments program: Control of flexible robot manipulators in zero gravity, experiment definition phase

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    The results obtained show that it is possible to control light-weight robots with flexible links in a manner that produces good response time and does not induce unacceptable link vibrations. However, deflections induced by gravity cause large static position errors with such a control system. For this reason, it is not possible to use this control system for controlling motion in the direction of gravity. The control system does, on the other hand, have potential for use in space. However, in-space experiments will be needed to verify its applicability to robots moving in three dimensions

    Energy Conversion and Utilization Technologies Program (ECUT) electrocatalysis research

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    The general field of electrocatalysis, from both the technical and business standpoints is accessed and research areas and approaches most likely to lead to substantial energy/cost savings are identified. The overall approach was to compile and evaluate available information, relying heavily on inputs/recommendations of research managers and technical personnel in responsible positions in industry and at universities. Some promising approaches identified to date include the use of transition metal compounds as electrocatalysts and the use of the new electrochemical photocapacitance spectroscopy (EPS) technique for electrocatalyst characterization/development. For the first time, an oxygen electrocatalyst based on the K2NiF4 structure was synthesized, investigated and compared with a perovskite analog. Results show that this class of materials, based on Ni(3+), forms very efficient and stable O2 anodes in basic solution and suggest that other structure-types be examined in this regard. The very difficult problem of dinitrogen and carbon dioxide electroreductions is addressed through the use of biological model systems which can mimic the enzyme processes in nature

    User's appraisal of yield model evaluation criteria

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    The five major potential USDA users of AgRISTAR crop yield forecast models rated the Yield Model Development (YMD) project Test and Evaluation Criteria by the importance placed on them. These users were agreed that the "TIMELINES" and "RELIABILITY" of the forecast yields would be of major importance in determining if a proposed yield model was worthy of adoption. Although there was considerable difference of opinion as to the relative importance of the other criteria, "COST", "OBJECTIVITY", "ADEQUACY", AND "MEASURES OF ACCURACY" generally were felt to be more important that "SIMPLICITY" and "CONSISTENCY WITH SCIENTIFIC KNOWLEDGE". However, some of the comments which accompanied the ratings did indicate that several of the definitions and descriptions of the criteria were confusing

    Why Children’s Suggestibility Remains a Serious Concern

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    Warren and Marsil focus on six areas representing some of the most intractable problems that will require further attention from scientists and practitioners alike. Research on child witnesses is highlighted, concentrating primarily on studies published or presented in the past ten years

    Obituary: Ross McDonald Parish (1928 - 2001)

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    Teaching/Communication/Extension/Profession,

    Postnatal debriefing: Have we thrown the baby out with the bathwater?

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    Postnatal debriefing is offered by 78% of maternity services in the UK despite little evidence from randomized controlled trials (RCTs) that it is effective. RCTs in this area have applied debriefing as a prophylactic to all or high risk women, rather than as a treatment for women who request it. This pragmatic trial therefore evaluated existing postnatal debriefing services that provide debriefing as a treatment for women who request it. Forty-six women who met criterion A for post-traumatic stress disorder (PTSD) and requested debriefing 1.3 to 72.2 months (median 16 weeks) postpartum completed measures of depression, PTSD, support and negative appraisals of the birth before and one month after debriefing. Women were compared with others who gave birth in the same hospitals during the same time period (n=34), who met criterion A for PTSD but had not requested debriefing. Results showed PTSD symptoms reduced over time in both groups but greater decreases were observed in women who attended debriefing. Debriefing also led to reduction in negative appraisals but did not affect symptoms of depression. Therefore, results suggest providing debriefing as a treatment to women who request or are referred to it may help to reduce symptoms of PTSD
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