2,965 research outputs found

    Telecommunications and data acquisition systems support for Voyager missions to Jupiter and Saturn, 1972-1981, prelaunch through Saturn encounter

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    The Deep Space Network has supported the Voyager Project for approximately nine years, during which time implementation, testing, and operational support was provided. Four years of this time involved testing prior to launch; the final five years included network operations support and additional network implementation. Intensive and critical support intervals included launch and four planetary encounters. The telecommunications and data acquisition support for the Voyager Missions to Jupiter and Saturn are summarized

    The effectiveness of teamwork training on teamwork behaviors and team performance : A systematic review and meta-analysis of controlled interventions

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    The objective of this study was to conduct a systematic review and meta-analysis of teamwork interventions that were carried out with the purpose of improving teamwork and team performance, using controlled experimental designs. A literature search returned 16,849 unique articles. The meta-analysis was ultimately conducted on 51 articles, comprising 72 (k) unique interventions, 194 effect sizes, and 8439 participants, using a random effects model. Positive and significant medium-sized effects were found for teamwork interventions on both teamwork and team performance. Moderator analyses were also conducted, which generally revealed positive and significant effects with respect to several sample, intervention, and measurement characteristics. Implications for effective teamwork interventions as well as considerations for future research are discussed

    Advanced single permanent magnet axipolar ironless stator ac motor for electric passenger vehicles

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    A program was conducted to design and develop an advanced-concept motor specifically created for propulsion of electric vehicles with increased range, reduced energy consumption, and reduced life-cycle costs in comparison with conventional systems. The motor developed is a brushless, dc, rare-earth cobalt, permanent magnet, axial air gap inductor machine that uses an ironless stator. Air cooling is inherent provided by the centrifugal-fan action of the rotor poles. An extensive design phase was conducted, which included analysis of the system performance versus the SAE J227a(D) driving cycle. A proof-of-principle model was developed and tested, and a functional model was developed and tested. Full generator-level testing was conducted on the functional model, recording electromagnetic, thermal, aerodynamic, and acoustic noise data. The machine demonstrated 20.3 kW output at 1466 rad/s and 160 dc. The novel ironless stator demonstated the capability to continuously operate at peak current. The projected system performance based on the use of a transistor inverter is 23.6 kW output power at 1466 rad/s and 83.3 percent efficiency. Design areas of concern regarding electric vehicle applications include the inherently high windage loss and rotor inertia

    New results on GP Com

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    We present high resolution optical and UV spectra of the 46 min orbital period, helium binary, GP Com. Our data contains simultaneous photometric correction which confirms the flaring behaviour observed in previous optical and UV data. In this system all lines show a triple peaked structure where the outer two peaks are associated with the accretion disc around the compact object. The main aim of this paper is to constrain the origin of the central peak, also called ``central spike''. We find that the central spike contributes to the flare spectra indicating that its origin is probably the compact object. We also detect that the central spike moves with orbital phase following an S-wave pattern. The radial velocity semiamplitude of the S-wave is ~10 km/s indicating that its origin is near the centre of mass of the system, which in this case lies very close to the white dwarf. Our resolution is higher than that of previous data which allows us to resolve structure in the central peak of the line. The central spike in three of the HeI lines shows another peak blueshifted with respect to the main peak. We propose that one of the peaks is a neutral helium forbidden transition excited in a high electron density region. This forbidden transition is associated with the permitted one (the stronger peak in two of the lines). The presence of a high electron density region again favours the white dwarf as their origin.Comment: 14 pages, 16 figures. Accepted for publication in A&

    Resilience to climate shocks in the tropics

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    This focus collection on resilience to climate shocks in the tropics draws together 16 papers that predominantly examine the impacts of, and responses to, the 2015/2016 El Niño-Southern Oscillation event, in a range of contexts. This introductory synthesis contextualises the collection of papers by reviewing important concepts and highlighting some important insights that emerge from the collection. The papers in this collection collectively highlight: the value of longitudinal and interdisciplinary research in understanding both the roots of, and responses to, resilience challenges; the critical interaction between climatic and land-use changes; and the ways in which governance arrangements underpin societal decision-making across a range of scales and contexts to shape resilience

    Predicting exercise motivation and exercise behavior: A moderated mediation model testing the interaction between perceived exercise variety and basic psychological needs satisfaction

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    Objectives Perceived variety in exercise predicts exercise behavior through autonomous motivation. However, psychological need satisfaction (viz. for competence, autonomy, and relatedness) may moderate the relationship between perceived variety in exercise and exercise behavior (through autonomous motivation). The purpose of the present study was to examine whether the satisfaction of the basic psychological needs in exercise contexts moderates the mediating role of autonomous exercise motivation in the relationship between perceived variety in exercise and exercise behavior. Design Cross-sectional. Method Adults (N = 499) completed an online questionnaire to measure the study variables. Associations were examined using structural equation modeling. Results Psychological need satisfaction moderated the positive indirect relationship between perceived exercise variety and self-reported exercise behavior (via autonomous motivation) such that perceived variety was associated with exercise behavior when psychological need satisfaction scores were lower than average. Conclusions Based on these findings, perceived exercise variety may act as a compensatory source of motivation when psychological need satisfaction is low. In addition to attempting to foster need-supportive exercise contexts, it may be particularly important for exercise promotion specialists to foster the experience of variety among individuals who have lower psychological need satisfaction

    The Right to Know and the Right Not to Know Revisited: Part One

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    Prompted by developments in human genetics, a recurrent bioethical question concerns a person’s ‘right to know’ and ‘right not to know’ about genetic information held that is intrinsically related to or linked to them. In this paper, we will revisit the claimed rights in relation to two particular test cases. One concerns the rights of the 500,000 participants in UK Biobank (UKB) whose biosamples, already having been genotyped, will now be exome sequenced; and the other concerns the rights of pregnant women (and their children) who undergo non-invasive prenatal testing (NIPT)—a simple blood test that can reveal genetic information about both a fetus and its mother. This two-part paper is in four principal sections. First, we sketch the relevant features of our two test cases. Secondly, we consider the significance of recent legal jurisprudence in the UK and Singapore. Thirdly, we consider how, the jurisprudence apart, the claimed rights might be grounded. Fourthly, we consider the limits on the rights. We conclude with some short remarks about the kind of genetically aware society that we might want to be and how far there is still an opportunity meaningfully to debate the claimed rights

    The Application of Transformational Leadership Theory to Parenting: Questionnaire Development and Implications for Adolescent Self-Regulatory Efficacy and Life Satisfaction

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    We draw upon transformational leadership theory to develop an instrument to measure transformational parenting for use with adolescents. First, potential items were generated that were developmentally appropriate and evidence for content validity was provided through the use of focus groups with parents and adolescents. We subsequently provide evidence for several aspects of construct validity of measures derived from the Transformational Parenting Questionnaire (TPQ). Data were collected from 857 adolescents (Mage = 14.70 years), who rated the behaviors of their mothers and fathers. The results provided support for a second-order measurement model of transformational parenting. In addition, positive relationships between mothers’ and fathers’ transformational parenting behaviors, adolescents’ self-regulatory efficacy for physical activity and healthy eating, and life satisfaction were found. The results of this research support the application of transformational leadership theory to parenting behaviors, as well as the construct validity of measures derived from the TPQ. (AUTHORS' ABSTRACT

    Individual freedom versus collective responsibility: an ethicist's perspective

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    Philosophical theories of collective action have produced a number of alternative accounts of the rationality and morality of self-interest and altruism. These have obvious applications to communicable disease control, the avoidance of antibiotic resistance, the responsibility of healthcare professionals to patients with serious communicable diseases, and the sharing of personal data in epidemiological research
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