186 research outputs found
Torque Production in a Halbach Machine
The NASA John H. Glenn Research Center initiated the investigation of torque production in a Halbach machine for the Levitated Ducted Fan (LDF) Project to obtain empirical data in determining the feasibility of using a Halbach motor for the project. LDF is a breakthrough technology for "Electric Flight" with the development of a clean, quiet, electric propulsor system. Benefits include zero emissions, decreased dependence on fossil fuels, increased efficiency, increased reliability, reduced maintenance, and decreased operating noise levels. A commercial permanent magnet brushless motor rotor was tested with a custom stator. An innovative rotor utilizing a Halbach array was designed and developed to fit directly into the same stator. The magnets are oriented at 90deg to the adjacent magnet, which cancels the magnetic field on the inside of the rotor and strengthens the field on the outside of the rotor. A direct comparison of the commercial rotor and the Halbach rotor was made. In addition, various test models were designed and developed to validate the basic principles described, and the theoretical work that was performed. The report concludes that a Halbach array based motor can provide significant improvements in electric motor performance and reliability
Development of a 32 Inch Diameter Levitated Ducted Fan Conceptual Design
The NASA John H. Glenn Research Center has developed a revolutionary 32 in. diameter Levitated Ducted Fan (LDF) conceptual design. The objective of this work is to develop a viable non-contact propulsion system utilizing Halbach arrays for all-electric flight, and many other applications. This concept will help to reduce harmful emissions, reduce the Nation s dependence on fossil fuels, and mitigate many of the concerns and limitations encountered in conventional aircraft propulsors. The physical layout consists of a ducted fan drum rotor with blades attached at the outer diameter and supported by a stress tuner ring at the inner diameter. The rotor is contained within a stator. This concept exploits the unique physical dimensions and large available surface area to optimize a custom, integrated, electromagnetic system that provides both the levitation and propulsion functions. The rotor is driven by modulated electromagnetic fields between the rotor and the stator. When set in motion, the time varying magnetic fields interact with passive coils in the stator assembly to produce repulsive forces between the stator and the rotor providing magnetic suspension. LDF can provide significant improvements in aviation efficiency, reliability, and safety, and has potential application in ultra-efficient motors, computers, and space power systems
Comparison of attitudes to media representation of mental illness between journalists and mental health professionals in Russia with German-speaking countries of Switzerland, Germany, and Austria
Background: The media are an important source of information on mental health. They are often implicit in reinforcing negative stereotypes of people with mental health problems. There are no studies in German-speaking countries or Russia on media attitudes to mental health and mental health professionalsâ (MHP) attitudes to the media. Aims: This study explored journalists and MHPs attitudes to mental health media reporting in the German speaking countries of Switzerland, Germany, and Austria and in Russia. Methods: A cross-sectional online internet survey, of ten Likert scale statements to ascertain perceptions of stigma, role, and training needs following the STROBE guidance was conducted among journalists and MHPs via their professional organizations. A non-discriminatory exponential snowballing technique leading to non-probability sampling was used. Descriptive statistics, Kruskal-Wallis, and a post hoc Dunnâs multiple comparisons test using Bonferroni adjustment were used to analyze data. Results: A total of 106 German-speaking and 78 Russian journalists, 109 German-speaking, and 82 Russian MHPs fully answered the survey. Journalists felt the media were more balanced about mental health than MHPs, and MHPs were wary of engagement with the media. Small minorities of journalists had engaged with mental health training, similarly few MHPs had engaged with media training, but both groups were interested in doing so in the future. Significant differences between German and Russian speaking respondents were found on a range of issues (e.g. stigmatization, image about psychotherapy, the media/MHPs, and their own role in engaging with the media/MHPs). Russians were more likely to know specialized (media/mental health awareness) training compared to German-speaking MHPs and journalists. Conclusion: There are potential opportunities to engage journalists and MHPs in training about each otherâs worlds and reducing stigma toward mental illness through engaging MHPs with the media. </jats:sec
Experimental evidence of a fractal dissipative regime in high-T_c superconductors
We report on our experimental evidence of a substantial geometrical
ingredient characterizing the problem of incipient dissipation in high-T_c
superconductors(HTS): high-resolution studies of differential
resistance-current characteristics in absence of magnetic field enabled us to
identify and quantify the fractal dissipative regime inside which the actual
current-carrying medium is an object of fractal geometry. The discovery of a
fractal regime proves the reality and consistency of critical-phenomena
scenario as a model for dissipation in inhomogeneous and disordered HTS, gives
the experimentally-based value of the relevant finite-size scaling exponent and
offers some interesting new guidelines to the problem of pairing mechanisms in
HTS.Comment: 5 pages, 3 figures, RevTex; Accepted for publication in Physical
Review B; (figures enlarged
Broadening and deepening or broadening versus deepening: The question of enlargement and Europe's 'hesitant Europeans'
R2P from Below: Does the British Public View Humanitarian Interventions as Ethical and Effective?
One of the major barriers to the implementation of the Responsibility to Protect principle is the lack of a political will. Public attitudes towards intervention will have a crucial impact on elite willingness to prevent mass atrocities, yet we have little understanding of the factors that influence those attitudes. This article provides the first examination of UK public perceptions about the moral justifiability and effectiveness of humanitarian interventions. The article shows that decisions about justifiability and effectiveness are very different. Attitudes towards justification were more easily explained suggesting that judgements about effectiveness are more contextual and less easily accounted for by individualsâ background characteristics and attitudes. Experiences with both Iraq and Afghanistan have contaminated public perceptions of both the ethics and effectiveness of humanitarian interventions. Although the public is broadly supportive about the justifiability of humanitarian interventions they are extremely sceptical about the likelihood that those interventions will be successful
With or without force? : European public opinion on democracy promotion
A Large part of the education provided at colleges and universities of today requires for thestudent to be more independent in their studies. This demands that the physical space,where the students choose to study, is designed in a way that can encourage and supportlearning. It seems as though that many of the learning spaces of today donât always meetthe studentsâ needs. The university library at the University of UmeĂ„ is currently planningto design new learning spaces for the students. The aim of this study is to examine how thephysical learning space can be designed to engage and encourage the students in theirlearning process. Based on literature describing learning spaces we have initially identified three mainareas to examine- Learning, Information Technology and Learning space design. Theseareas are all important features in the design of new learning spaces. With informationdrawn from that literature we conducted an empirical study at the library of the Universityof UmeĂ„. The empirical study was carried out through observations and focus groupinterviews. To give us more insight about the studentsâ thoughts about the learning spacewe also compared our findings with a survey conducted by the library personnel in 2008and 2010. The result of our study shows that there are some areas to be improved in theexisting learning space. The students are working more collaboratively which requiresmore group areas. Our study also shows that flexibility, more student interaction and asocial and engaging environment are all important features in the design of new learningspaces
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Globalisation from Above? Corporate Social Responsibility, the Workers' Party and the Origins of the World Social Forum
In its assessment of the origins and early development of the World Social Forum this article challenges traditional understandings of the Forum as representing âglobalisation from belowâ. By tracing the intricate relations among elements of business, civil society, and the Workersâ Party in the first years of the Forum, this article reveals the major role played by a corporate movement stemming from the Brazilian democratisation process in the 1980s, and how this combined with the transformed agenda of the Workersâ Party as it gained higher political offices to constrain the Forumâs activities from the outset. In so doing, this article challenges not only widespread conceptions of the Forum as a counterâhegemonic alternative but also current critiques concerning its subsequent limitations. Furthermore, it reveals how traditional understandings of the World Social Forum and of global civil society are underpinned by flawed assumptions which typecast political activities in the global âSouthâ
PERAN ORANG TUA DALAM MEMBINA NILAI KARAKTER ANAK DI KECAMATAN SIMPANG TIGA ACEH BESAR
ABSTRAKRahmayanti KS, Sri. 2016. Peran Orang Tua Dalam Membina Nilai Karakter Anak di Kecamatan Simpang Tiga Kabupaten Aceh Besar. Skripsi, Jurusan Pendidikan Kesejahteraan Keluarga, Fakultas Keguruan dan Ilmu Pendidikan, Universitas Syiah Kuala. Pembimbing:(1)Dr. Anizar Ahmad, M.Pd., (2). Dra. Fitriana, M.SI.Kata Kunci: Nilai Karakter Anak, Peran Orang TuaPeran orang tua adalah partisipasi atau kesadaran jiwa orang tua untuk memperdulikan anaknya, terutama dalam hal memberikan dan memenuhi kebutuhan hidup anaknya baik dari segi sosial maupun material. Penelitian ini untuk mengetahui usaha orang tua dalam membina nilai karakter anak di Kecamatan Simpang Tiga Kabupaten Aceh Besar. Penelitian ini bertujuan untuk (1) mengetahui usaha yang dilakukan orang tua dalam membina nilai karakter anak dan (2) mengetahui sistem pengawasan yang diterapkan oleh orang tua terhadap anak. Metode yang digunakan dalam penelitian ini adalah metode deskriptif kuantitatif. Data penelitian ini bersumber dari orang tua yang memiliki anak usia 4 sampai 10 tahun berjumlah 28 keluarga, pengumpulan data menggunakan kuisioner. Pengolahan data penelitian ini menggunakan rumus persentase. Simpulan penelitian ini berpengaruh pada usaha orang tua dalam membina nilai karakter anak, walau sebagian kecil yang mengetahui nilai-nilai karakter, tetapi sebagian besar sudah berusaha menanamkan nilai karakter tersebut. Lebih dari setengah responden menanamkan nilai religius kepada anak dengan tujuan agar anak mempunyai akhlak yang mulia kedepannya. Sedangkan yang berperan dalam membina nilai karakter anak adalah suami dan istri. Sistem pengawasan yang diterapkan orang tua berpengaruh terhadap pembentukkan nilai karakter anak. Seluruh anak termasuk kedalam katagori anak yang mudah bersahabat. Penanaman nilai karakter pada anak di mulai pada awal masa kanak-kanak ketika berumur 2-6 tahun. Responden juga menerapkan perilaku disiplin kepada anak karena usia awal kanak-kanak merupakan usia yang masih rentan, dan akan meniru semua yang dikerjakan oleh orang tuanya. Saran untuk orang tua agar dapat mendidik anaknya dengan baik, tidak mengedepankan emosi, dapat meluangkan waktu, adanya komunikasi yang dibina orang tua dengan anak, dan jangan bersikap apatis terhadap apa yang dikerjakan sianak
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