128 research outputs found
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
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
Propulsion Investigation for Zero and Near-Zero Emissions Aircraft
As world emissions are further scrutinized to identify areas for improvement, aviation s contribution to the problem can no longer be ignored. Previous studies for zero or near-zero emissions aircraft suggest aircraft and propulsion system sizes that would perform propulsion system and subsystems layout and propellant tankage analyses to verify the weight-scaling relationships. These efforts could be used to identify and guide subsequent work on systems and subsystems to achieve viable aircraft system emissions goals. Previous work quickly focused these efforts on propulsion systems for 70- and 100-passenger aircraft. Propulsion systems modeled included hydrogen-fueled gas turbines and fuel cells; some preliminary estimates combined these two systems. Hydrogen gas-turbine engines, with advanced combustor technology, could realize significant reductions in nitrogen emissions. Hydrogen fuel cell propulsion systems were further laid out, and more detailed analysis identified systems needed and weight goals for a viable overall system weight. Results show significant, necessary reductions in overall weight, predominantly on the fuel cell stack, and power management and distribution subsystems to achieve reasonable overall aircraft sizes and weights. Preliminary conceptual analyses for a combination of gas-turbine and fuel cell systems were also performed, and further studies were recommended. Using gas-turbine engines combined with fuel cell systems can reduce the fuel cell propulsion system weight, but at higher fuel usage than using the fuel cell only
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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
Power grid simulation considering electric vehicles and renewable energy sources
Transitioning to more sustainable energy systems may require a deep change in the energy, building and transportation sectors. Power generation from renewable energy sources is becoming more and more pervasive. New transportation mobility schemes are growing more popular. Increased attention is more and more devoted to energy efficiency in buildings. For these reasons, the ability to model the interaction of renewable energy sources with the added demand from Electric Vehicles would be an important tool for urban planners, electricity providers, and policymakers alike. This work develops a basic model for this interaction. It further presents the MIT campus as a case study using building consumption from Energize-MIT, a database developed as part of MITs Climate Action Plan
Space Vehicle Power System Comprised of Battery/Capacitor Combinations
Recent improvements in energy densities of batteries open the possibility of using electric rather that hydraulic actuators in space vehicle systems. However, the systems usually require short-duration, high-power pulses. This power profile requires the battery system to be sized to meet the power requirements rather than stored energy requirements, often resulting in a large and inefficient energy storage system. Similar transient power applications have used a combination of two or more disparate energy storage technologies. For instance, placing a capacitor and a battery side-by-side combines the high energy density of a battery with the high power performance of a capacitor and thus can create a lighter and more compact system. A parametric study was performed to identify favorable scenarios for using capacitors. System designs were then carried out using equivalent circuit models developed for five commercial electrochemical capacitor products. Capacitors were sized to satisfy peak power levels and consequently "leveled" the power requirement of the battery, which can then be sized to meet system energy requirements. Simulation results clearly differentiate the performance offered by available capacitor products for the space vehicle applications
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