845 research outputs found

    ESTIMATION OF THE SPACE SHUTTLE ROLLOUT FORCING FUNCTION

    Get PDF
    The Space Shuttle Vehicle is assembled in the Vertical Assembly Building (VAB) at Kennedy Space Flight Center in Florida. The Vehicle is stacked on a Mobile Launch Platform (MLP) that weighs eight million pounds. A Crawler Transporter (CT) then carries the MLP and the stacked vehicle (12 million pounds total weight) to the launch complex located 5 miles away. This operation is performed at 0.9 mph resulting in a 4.5-hour transport. A recent test was performed to monitor the dynamic environment that was produced during rollout. It was found that the rollout is a harmonic-rich dynamic environment that was previously not understood. This paper will describe work that has been performed to estimate the forcing function that is produced in the transportation process. The rollout analysis team has determined that there are two families of harmonics of the drive train, which excite the system as a function of CT speed. There are also excitation sources, which are random or narrow-band in frequency and are not a function of CT speed. This presentation will discuss the application of the Sum of Weighted Accelerations Technique (SWAT) to further refine this understanding by estimating the forces and moments at the center-of-mass

    Promised incentives on a random digit dial survey

    Full text link
    Die Verfasser legen die Ergebnisse von zwei Experimenten vor, mit denen die Wirkung von versprochenen Belohnungen bei einer Random-Digit-Dial-Untersuchung im Stadium der GesprĂ€chseröffnung sowie im Stadium der Aufgabe einer anfĂ€nglichen Verweigerungshaltung untersucht werden sollte. In beiden FĂ€llen zeigte sich kein Effekt. Dieses Ergebnis steht im Widerspruch zu mindestens einem weiteren Experiment aus jĂŒngster Zeit sowie auch zum Einsatz versprochener Belohnungen zur Reduktion von Antwortverweigerung bei mehreren Meinungsforschungsinstituten. Die Verfasser diskutieren mögliche Ursachen fĂŒr das Ausbleiben eines Effekts. (ICEÜbers)"This paper presents the results of two experiments carried out to test the effectiveness of promised incentives for a random digit dial survey (RDD) at the initial household contact (introduction) and at the stage of refusal conversion. The results of the experiments find no effect of at either stage of the survey process. These results are contrary to those found by at least one other recent experiment, as well as the use of promised incentives used routinely to convert reluctant respondents by several survey organizations. The possible reasons for not finding an effect are discussed." (author's abstract

    Undergraduate nurses reflections on Whatsapp use in improving primary health care education

    Get PDF
    Background: The global use of mobile devices with their connectivity capacity, and integrated with the affordances of social media networks, provides a resource-rich platform for innovative student-directed learning experiences. Objective: The objective of this study was to review the experiences of undergraduate nurses on the improvement of primary health care education at a School of Nursing at a University in the Western Cape, South Africa, through the incorporation of a social media application, WhatsApp. Method: A qualitative, exploratory, descriptive, and contextual design was used to explore and describe data collected from a purposive sample of 21 undergraduate nursing students. The study population was engaged in a WhatsApp discussion group to enhance their integration of theory and clinical practice of the health assessment competency of the Primary Health Care Module. Participants submitted electronic reflections on their experiences in the WhatsApp discussion group via email on completion of the study. Thematic analysis of the qualitative data collected was done according to Tesch’s (1990) steps of descriptive data analysis in order to identify the major themes in the study. The electronic reflections were analysed to explore their rich, reflective data. Results: Seven themes were identified that included: positive experiences using the WhatsApp group; the usefulness of WhatsApp for integrating theory and clinical practice; the availability of resources for test preparation; opportunity for clarification; anonymity; exclusion of students as a result of the lack of an appropriate device, and the application caused the battery of the device to run flat quickly. Conclusion: The results of the experiences of students in the WhatsApp discussion group could be used to inform the use of social media applications in teaching and learning, with the purpose of enhancing the integration of the theory and clinical practice.Department of HE and Training approved lis

    Science Meets Traditional Knowledge: Water and Climate in the Sahtu (Great Bear Lake) Region, Northwest Territories, Canada

    Get PDF
    In July 2005, several scientists from the Mackenzie GEWEX (Global Energy and Water Cycle Experiment) Study, known as MAGS, met with aboriginal people in Deline on the shore of Great Bear Lake to exchange information on climate and water in the region. Topics discussed pertained directly to the northern environment, and they included climate variability and change, wind, lightning, lake ice, lake level, and streamflow. The traditional knowledge shared by the residents is a rich source of local expertise about the landscape and climate systems of the Deline area, while the scientific knowledge provided by MAGS presents a scientific basis for many observed climate and water phenomena, particularly on a broad regional scale. Through cordial and open discussions, the meeting facilitated the sharing of traditional knowledge and scientific results. The meeting enhanced the potential for traditional knowledge to help direct and validate scientific investigations and for scientific knowledge to be used in conjunction with traditional knowledge to guide community decision making.En juillet 2005, plusieurs scientifiques de l’étude Mackenzie GEWEX (expĂ©rience internationale sur l’énergie et le cycle hydrologique), connue sous le nom de MAGS, ont rencontrĂ© les Autochtones de Deline, sur la cĂŽte du Grand lac de l’Ours dans le but d’échanger des donnĂ©es sur les conditions climatiques et hydrologiques de la rĂ©gion. Les sujets Ă  l’étude se rapportaient directement Ă  l’environnement nordique, plus prĂ©cisĂ©ment la variabilitĂ© et le changement climatiques, le vent, la foudre, la glace lacustre, le niveau des lacs et le dĂ©bit des cours d’eau. Les connaissances traditionnelles des habitants de la rĂ©gion reprĂ©sentent une riche source d’expertise locale au sujet du paysage et des systĂšmes climatiques de la rĂ©gion de Deline, tandis que les connaissances scientifiques fournies par MAGS constituent une base scientifique pour de nombreux phĂ©nomĂšnes climatiques et hydrologiques observĂ©s, surtout sur une vaste Ă©chelle rĂ©gionale. GrĂące Ă  des discussions cordiales et ouvertes, cette rĂ©union a donnĂ© lieu au partage de connaissances traditionnelles et de rĂ©sultats scientifiques. Cette rĂ©union a Ă©galement permis d’accroĂźtre la possibilitĂ© que les connaissances traditionnelles aident Ă  diriger et Ă  valider les enquĂȘtes scientifiques, et que les connaissances scientifiques soient employĂ©es de pair avec les connaissances traditionnelles pour favoriser la prise de dĂ©cisions au sein de la collectivitĂ©

    Proportionate methods for evaluating a simple digital mental health tool

    Get PDF
    Background: Traditional evaluation methods are not keeping pace with rapid developments in mobile health. More flexible methodologies are needed to evaluate mHealth technologies, particularly simple, self-help tools. One approach is to combine a variety of methods and data to build a comprehensive picture of how a technology is used and its impact on users. Objective: This paper aims to demonstrate how analytical data and user feedback can be triangulated to provide a proportionate and practical approach to the evaluation of a mental wellbeing smartphone app (‘In Hand’). Methods: A three-part process was used to collect data: 1) app analytics; 2) an online user survey; and 3) interviews with users. Findings: Analytics showed that >50% of user sessions counted as ‘meaningful engagement’. User survey findings (N=108) revealed that In Hand was perceived to be helpful on several dimensions of mental wellbeing. Interviews (N=8) provided insight into how these self-reported positive effects were understood by users. Conclusions: This evaluation demonstrates how different methods can be combined to complete a real-world, naturalistic evaluation of a self-help digital tool and provide insights into how and why an app is used and its impact upon users’ wellbeing. Clinical implications: This triangulation approach to evaluation provides insight into how wellbeing apps are used and their perceived impact on users’ mental wellbeing. This approach is useful for mental healthcare professionals and commissioners who wish to recommend simple digital tools to their patients and evaluate their uptake, use and benefits

    A comparison of host gene expression signatures associated with infection in vitro by the Makona and Ecran (Mayinga) variants of Ebola virus

    Get PDF
    The Ebola virus (EBOV) variant Makona (which emerged in 2013) was the causative agent of the largest outbreak of Ebola Virus Disease recorded. Differences in virus-host interactions between viral variants have potential consequences for transmission, disease severity and mortality. A detailed profile of the cellular changes induced by the Makona variant compared with other Ebola virus variants was lacking. In this study, A549 cells, a human cell line with a robust innate response, were infected with the Makona variant or with the Ecran variant originating from the 1976 outbreak in Central Africa. The abundance of viral and cellular mRNA transcripts was profiled using RNASeq and differential gene expression analysis performed. Differences in effects of each virus on the expression of interferon-stimulated genes were also investigated in A549 NPro cells where the type 1 interferon response had been attenuated. Cellular transcriptomic changes were compared with those induced by human respiratory syncytial virus (HRSV), a virus with a similar genome organisation and replication strategy to EBOV. Pathway and gene ontology analysis revealed differential expression of functionally important genes; including genes involved in the inflammatory response, cell proliferation, leukocyte extravasation and cholesterol biosynthesis. Whilst there was overlap with HRSV, there was unique commonality to the EBOV variants

    Change in psychopathology in referred children: The role of life events and perceived stress

    Get PDF
    Background: This study examined the relation between stress and change in emotional and behavioural problems in children and adolescents referred for mental health services. Method: At three waves across four years, children and their parents (N = 310, mean age at the first wave = 11.26 years, SD = 3.18) reported emotional and behavioural problems, as well as stressful life events (parent report) and perceived stress (child report). Results: Major life events before referral were associated with higher levels of parent-reported internalising and externalising problems at referral. Life events after referral were associated with a slower recovery from internalising problems. The associations between stressful life events and the course of parent- and self-reported problems were mediated by children's subjective feelings of stress. Conclusion: Stressful life events appear to interfere with recovery from internalising problems in the years after referral through increasing the experience of stress in daily life

    'To live and die [for] Dixie': Irish civilians and the Confederate States of America

    Get PDF
    Around 20,000 Irishmen served in the Confederate army in the Civil War. As a result, they left behind, in various Southern towns and cities, large numbers of friends, family, and community leaders. As with native-born Confederates, Irish civilian support was crucial to Irish participation in the Confederate military effort. Also, Irish civilians served in various supporting roles: in factories and hospitals, on railroads and diplomatic missions, and as boosters for the cause. They also, however, suffered in bombardments, sieges, and the blockade. Usually poorer than their native neighbours, they could not afford to become 'refugees' and move away from the centres of conflict. This essay, based on research from manuscript collections, contemporary newspapers, British Consular records, and Federal military records, will examine the role of Irish civilians in the Confederacy, and assess the role this activity had on their integration into Southern communities. It will also look at Irish civilians in the defeat of the Confederacy, particularly when they came under Union occupation. Initial research shows that Irish civilians were not as upset as other whites in the South about Union victory. They welcomed a return to normalcy, and often 'collaborated' with Union authorities. Also, Irish desertion rates in the Confederate army were particularly high, and I will attempt to gauge whether Irish civilians played a role in this. All of the research in this paper will thus be put in the context of the Drew Gilpin Faust/Gary Gallagher debate on the influence of the Confederate homefront on military performance. By studying the Irish civilian experience one can assess how strong the Confederate national experiment was. Was it a nation without a nationalism
    • 

    corecore