25,131 research outputs found

    Characterization of polybenzimidazole (PBI) film at high temperatures

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    Polybenzimidazole, a linear thermoplastic polymer with excellent thermal stability and strength retention over a wide range of temperatures, was evaluated for its potential use as the main dielectric in high temperature capacitors. The film was characterized in terms of its dielectric properties in a frequency range of 50 Hz to 100 kilo-Hz. These properties, which include the dielectric constant and dielectric loss, were also obtained in a temperature range from 20 C to 300 C with an electrical stress of 60 Hz, 50 V/mil present. The alternating and direct current breakdown voltages of silicone oil impregnated films as a function of temperature were also determined. The results obtained indicate that while the film remained relatively stable up to 200 C, it exhibited an increase in its dielectric properties as the temperature was raised to 300 C. It was also found that conditioning of the film by heat treatment at 60 C for six hours tended to improve its dielectric and breakdown properties. The results are discussed and conclusions made concerning the suitability of the film as a high temperature capacitor dielectric

    Working memory learning method and astrocytes number in different subfields of rat's Hippocampus

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    The aim of this study was evaluation of the astrocytes number in different subfields of rat's Hippocampus after spatial learning with usage of Morris Water Maze technique and working memory method. In this study, between 2005-2006 years in Pasteur institute of Iran-Tehran and histological department of Gorgan University with usage of Morris Water Maze and working memory technique, we used 14 male albino wistar rats. Seventh rats were in control group and 7 rats in working memory group. After histological preparation, the slides were stained with PTAH staining for showing the Astrocytes. Present results showed significant difference in astrocytes number in CA1, CA2 and CA3 areas of hippocampus between control and reference memory group. The number of astrocytes is increased in working memory group. Then we divided the hippocampus to three parts: Anterior, middle and posterior and with compare of different area (CA1, CA2 and CA3) of hippocampus, we found that the differences between Anterior-middle and Middle-Posterior of CA1 and CA2 area of hippocampus were significant, whereas the difference between Anterior-Posterior parts was not significant in CA1 and CA2 areas. In CA3 area, the difference between Anterior-Middle and Anterior-Posterior parts was significant, whereas the difference between middle and posterior parts was not significant. We concluded that the number of astrocytes increased due to spatial learning and working memory technique. © 2008 Science Publications

    AMCTD: Adaptive Mobility of Courier nodes in Threshold-optimized DBR Protocol for Underwater Wireless Sensor Networks

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    In dense underwater sensor networks (UWSN), the major confronts are high error probability, incessant variation in topology of sensor nodes, and much energy consumption for data transmission. However, there are some remarkable applications of UWSN such as management of seabed and oil reservoirs, exploration of deep sea situation and prevention of aqueous disasters. In order to accomplish these applications, ignorance of the limitations of acoustic communications such as high delay and low bandwidth is not feasible. In this paper, we propose Adaptive mobility of Courier nodes in Threshold-optimized Depth-based routing (AMCTD), exploring the proficient amendments in depth threshold and implementing the optimal weight function to achieve longer network lifetime. We segregate our scheme in 3 major phases of weight updating, depth threshold variation and adaptive mobility of courier nodes. During data forwarding, we provide the framework for alterations in threshold to cope with the sparse condition of network. We ultimately perform detailed simulations to scrutinize the performance of our proposed scheme and its comparison with other two notable routing protocols in term of network lifetime and other essential parameters. The simulations results verify that our scheme performs better than the other techniques and near to optimal in the field of UWSN.Comment: 8th International Conference on Broadband and Wireless Computing, Communication and Applications (BWCCA'13), Compiegne, Franc

    E-Commerce to Improve Homemaker Productivity (Women Entrepreneur Empowerment at Meruya Utara, Kembangan District, West Jakarta, Indonesia)

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    Saat ini banyak ibu rumah tangga memiliki bisnis sampingan yang sesuai dengan keterampilan dan hobi mereka. Adapun tujuan dari bisnis sampingan tersebut adalah untuk membantu kebutuhan keuangan rumah tangga mereka. Penelitian sebelumnya telah menunjukkan bahwa ibu rumah tangga yang juga pengusaha perempuan memiliki kontribusi yang signifikan terhadap kesejahteraan keluarga. Namun demikian, terdapat kesulitan dari ibu rumah tangga dalam memasarkan produk dan layanan mereka. Pengabdian ini melaksanakan sosialisasi terkait cara membuat akun e-commerce dan menggunakannya sebagai alternatif untuk menjual produk dan layanan mereka. Selain itu, hasil dari kegiatan layanan masyarakat Internasional ini adalah bahwa ibu rumah tangga dapat menjual produk dan layanan mereka melalui e-commerce. Menurut hasil survei pada kegiatan sosialisasi ini, diketahui bahwa hambatan bagi ibu rumah tangga adalah masih rendahnya pendidikan mereka dimana 65% dari mereka memiliki pendidikan sekolah menengah. Juga, kepemilikan aplikasi internet banking dan mobile banking masih rendah, yaitu 35%. Dengan demikian, kepemilikan yang rendah atas aplikasi internet banking dan mobile banking membuat mereka kesulitan untuk menjual produk dan layanannya melalui e-commerce. Semua peserta sosialisasi menyatakan bahwa kegiatan ini bermanfaat dan menambah pengetahuan mereka. Selanjutnya untuk dapat meningkatkan omset penjualan mereka adalah melalui perbaikan kemasan produk dan layanan mereka untuk membuatnya lebih menarik bagi pembeli.  Kata kunci: Ibu Rumah Tangga, Pengusaha Wanita, Mobile Banking, Internet Banking, E-Commerce. &nbsp

    Active neutrino Oscillations and the SNO neutral Current measurement

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    We discuss the relation between the observed CC, ES, and NC fluxes with the flavor fractional content of the solar neutrino flux seen by SNO. By using existing estimates of the cross sections for the charged and neutral current reactions which take into account the detector resolution, we show how the forthcoming SNO rates unconstrained by the standard 8^8B shape could test the oscillations into active states. We perform a model independent analysis for the Super-K and SNO data, assuming a non distorted spectrum.Comment: 6pages, 4 figure
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