1,172 research outputs found

    Non-equilibrium spatial distribution of Rashba spin torque in ferromagnetic metal layer

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    We study the spatial distribution of spin torque induced by a strong Rashba spin-orbit coupling (RSOC) in a ferromagnetic (FM) metal layer, using the Keldysh non-equilibrium Green's function method. In the presence of the s-d interaction between the non-equilibrium conduction electrons and the local magnetic moments, the RSOC effect induces a torque on the moments, which we term as the Rashba spin torque. A correlation between the Rashba spin torque and the spatial spin current is presented in this work, clearly mapping the spatial distribution of Rashba Spin torque in a nano-sized ferromagnetic device. When local magnetism is turned on, the out-of-plane (Sz) Spin Hall effect (SHE) is disrupted, but rather unexpectedly an in-plane (Sy) SHE is detected. We also study the effect of Rashba strength (\alpha_R) and splitting exchange (\Delta) on the non-equilibrium Rashba spin torque averaged over the device. Rashba spin torque allows an efficient transfer of spin momentum such that a typical switching field of 20 mT can be attained with a low current density of less than 10^6 A/cm^2

    Analisis terhadap Densitas Larva Nyamuk Aedes Aegypti (Vektor Penyakit Demam Berdarah Dengue/DBD)

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    Demam Berdarah Dengue (DBD) merupakan salah satu penyakit menular yang menjadi masalah kesehatan yang serius masyarakat di Indonesia. Hal ini sering menimbulkan kekhawatiran karena perjalanan penyakit DBD tergolong cepat dan dapat menimbulkan wabah serta kematian dalam waktu yang singkat. Monitoring kepadatan populasi Aedes aegypti sangat penting untuk membantu evaluasi dan peningkatan pemberantasan nyamuk penyebab DBD. Penelitian ini bertujuan untuk mengetahui densitas larva nyamuk Aedes aegypti berdasarkan angka House Index (HI), Container Index (CI) dan Breateu Index (BI). Penelitian ini merupakan penelitian deskriptif dengan pendekatan survei. Penelitian ini dilakukan di Kelurahan Samalewa, Kecamatan Bungoro, Kabupaten Pangkep, pada bulan Juli hingga Oktober 2014. Populasi dalam penelitian ini adalah seluruh rumah di Kelurahan Samalewa (2.246 rumah) dan sampel berjumlah 50 rumah yang diambil melalui metode proportional random sampling. Pengamatan jentik dilakukan dengan mengamati kehadiran jentik pada setiap kontainer yang terletak di dalam dan di luar rumah. Hasil penelitian menunjukkan bahwa secara keseluruhan persentase House Index bernilai sebesar 54%, Container Index sebesar 23.9% dan Breateu Index sebesar 110%. Berdasarkan nilai indeks tersebut, dapat disimpulkan bahwa Kelurahan Samalewa beresiko terhadap transmisi penyakit Demam Berdarah Dengue

    Kehidupan Waria di Kota Dumai (Studi Kasus Waria Menghadapi Tekanan Sosial)

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    Transvestites are men who prefer to play a role as women in their daily lives. Transvestites can be interpreted as analogous to the behavior of men who are graceful, soft and womanish .. The aim of this study was to identify and analyze the characteristics of transvestites, to know what are the social pressures experienced by transvestites and to know how or how transvestites face pressure social community. The theory used is the theory of aberration. Deviations are all actions that are not in accordance with the norms of social berlaku.Tekanan experienced by study subjects were from families and communities around such derision received by transvestites, the anger of families, punches and even evicted from the house by the family. Efforts made by the subject of research in facing social pressure is to run away from home to avoid ridicule from the local community and the anger and the blows that come from the family.Keywords: Sex, Deviant Behavior, effort and Pressur

    Gardening Coconut Farmers Local Wisdom In The Village Topang Kecamatan Rangsang Kabupaten Kepulauan Meranti

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    This research purpose of this study to analyze how the behavior of farmers in the Topang which has palm plantation which starts from clearing, processing, nursery, plant up to collect the results and the behavior of the last farmers in preparing the land. farmers cleared the land himself with reason as a source of livelihood. Farmers who cultivate farming land with their own hands, without having to hire someone else to do it. To be a successful farmer should do their own farmers to comply with what is expected by each farmer. The first beginning farmers develop their plantations without government permission letter regarding land ownership in processed by farmers because the government has not contributed at that time. Behavior of farmers in processing a piece of land to plantations was not using it by burning palm plantation farmers use the traditional way to keep the preservation of the environment. Their behavior shows that there must be a way to burn to cultivate a piece of land, but there are many more ways to do it wisely. The behavior of farmers who are still stuck with the old ways that do not cause damage to the function of forests. The accusations being leveled at farmers who cultivate land by burning was never true. Because farmers clearing land must pass through that long to work his land

    Electrochemical strategy for grown ZnO nanoparticles deposited onto HY zeolite with enhanced photodecolorization of methylene blue: Effect of the formation of Si O Zn bonds

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    Nanoparticles of electrogenerated zinc-supported HY zeolite (EGZnO/HY) catalyst were prepared by a simple electrochemical method. The interaction between zinc species and HY support during the electrolysis was found to affect the EGZnO/HY structure. In addition to the formation of EGZnO nanoparticles (<30 nm in size) that distributed on the surface of HY support, an isomorphous substitution of Al with Zn also occurred in the aluminosilicate framework to result in a Si O Zn bonds. The photoactivity of EGZnO/HY was tested on the decolorization of methylene blue (MB). An amount of 0.375 g L−1 of 1 wt% EGZnO/HY was found to be the optimum dosage for 10 mg L−1 MB, which resulted in 80% of maximum decolorization after 6 h of contact time at pH 3 under fluorescent light (420 nm). Increasing the EGZnO loading led to additional formation of Si O Zn bonds and lessened the number of EGZnO nanoparticles, which then reduced the photodecolorization percentage of MB.The photocatalytic reaction was follows the first-order Langmuir–Hinshelwood model, and gives partially mineralization. The photocatalyst was still stable after five cycling runs with no Zn leaching

    Nd:YAG laser welding of stainless steel 304 for photonics device packaging

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    Although pulsed Nd:YAG laser welding has been widely used in microelectronics and photonics packaging industry, a full understanding of various phenomena involved is still a matter of trials and speculations. In this research, an ultra compact pulsed Nd:YAG laser with wavelength of 1.064 µm has been used to produce a spot weld on stainless steel 304. The principal objective of this research is to examine the effects of laser welding parameters such as laser beam peak powers, pulse durations, incident angles, focus point positions and number of shots on the weld dimensions: penetration depth and bead width. The ratio of the penetration depth to the bead width is considered as one of the most critical parameters to determine the weld quality. It is found that the penetration depth and bead width increase when the laser beam peak power, pulse duration and number of shot increase. In contrast, the penetration depth decreases when the laser beam defocus position and incident angle increase. This is due to the reduction of the laser beam intensity causing by the widening of the laser spot size. These experimental results provide a reference on an optimal laser welding operations for a reliable photonics device packaging. The results obtained shows that stainless steel 304 is suitable to be used as a base material for photonics device packaging employing Nd:YAG laser welding technique

    Decomposition-assisted computational technique based on surrogate modeling for real-time simulations

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    The development of complex simulation systems is extremely costly as it requires high computational capability and expensive hardware. As cost is one of the main issues in developing simulation components, achieving real-time simulation is challenging and it often leads to intensive computational burdens. Overcoming the computational burden in a multidisciplinary simulation system that has several subsystems is essential in producing inexpensive real-time simulation. In this paper, a surrogate-based computational framework was proposed to reduce the computational cost in a high-dimensional model while maintaining accurate simulation results. Several well-known metamodeling techniques were used in creating a global surrogate model. Decomposition approaches were also used to simplify the complexities of the system and to guide the surrogate modeling processes. In addition, a case study was provided to validate the proposed approach. A surrogate-based vehicle dynamic model (SBVDM) was developed to reduce computational delay in a real-time driving simulator. The results showed that the developed surrogate-based model was able to significantly reduce the computing costs, unlike the expensive computational model. The response time in surrogate-based simulation was considerably faster than the conventional model. Therefore, the proposed framework can be used in developing low-cost simulation systems while yielding high fidelity and fast computational output. © 2017 Nariman Fouladinejad et al

    Textile Diamond Dipole and Artificial Magnetic Conductor Performance under Bending, Wetness and Specific Absorption Rate Measurements

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    Textile diamond dipole and Artificial Magnetic Conductor (AMC) have been proposed and tested under wearable and body centric measurements. The proposed antenna and AMC sheet are entirely made of textiles for both the substrate and conducting parts, thus making it suitable for wearable communications. Directive radiation patterns with high gain are obtained with the proposed AMC sheet, hence minimizing the radiation towards the human body. In this study, wearable and body centric measurements are investigated which include bending, wetness and Specific Absorption Rate (SAR). Bending is found not to give significant effect to the antenna and AMC performance, as opposed to wetness that yields severe performance distortion. However, the original performance is retrieved once the antenna and AMC dried. Moreover, notable SAR reduction is achieved with the introduction of the AMC sheet, which is appropriate to reduce the radiation that penetrates into human flesh
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