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51.
Dipankar Saha Amretashis Sengupta Sitangshu Bhattacharya Santanu Mahapatra 《Journal of Computational Electronics》2014,13(4):862-871
We report the effect of topological as well as lattice vacancy defects on the electro-thermal transport properties of the metallic zigzag graphene nano ribbons at their ballistic limit. We employ the density function theory–Non equilibrium green’s function combination to calculate the transmission details. We then present an elaborated study considering the variation in the electrical current and the heat current transport with the change in temperature as well as the voltage gradient across the nano ribbons. The comparative analysis shows, that in the case of topological defects, such as the Stone-Wales defect, the electrical current transport is minimum. Besides, for the voltage gradient of 0.5 Volt and the temperature gradient of 300 K, the heat current transport reduces by \({\sim }62\,\%\) and \({\sim }50\,\%\) for the cases of Stones-Wales defect and lattice vacancy defect respectively, compared to that of the perfect one. 相似文献
52.
Laminar flow and heal transfer in annular passages with axially nonuniform inner tubes are obtained numerically. A characteristic feature of these passages is that the flow separates in the streamwise direction. An axisymmetric coordinate system with an algebraic transformation in the radial direction kas been used. Fully elliptic vorticity-slream function and energy equations in the transformed coordinates are solved using an iterative alternate direction implicit (ADI) method. In an annulus with a smooth blockage, the flow separates immediately downstream of the blockage at Reynolds numbers greater than 100. The main features of the flow are established at a Reynolds number of 1000. The pressure drop is drastic near the maximum constriction. The heat flux is also high in the constricted region. A sharp increase in the heat transfer occurs where the fluid reattaches itself to the wall. The increase in the total pressure drop is about an order of magnitude greater than that in the average Nusselt number. 相似文献
53.
Patent law is the body of law governing the protection of rights to an invention made by an inventor and/or patent owner (such as a company or other organization which has obtained rights to a patent). Such an invention stems from an idea and may or may not result in a tangible product. Patent law protects the idea, and the owner of such an idea can prevent others from making, using, and selling a product that uses that idea by means of one or more associated patents. In the current global economic scenario, protection of intellectual property means protection from theft of potential profits that an individual or an organization can possibly make by commercialization of a patent and/or a family of patents related to a particular technology. 相似文献
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Design Space Exploration (DSE) with multi-parametric objective in High Level Synthesis (HLS) involves assessing the various design points in the architecture design space to find the optimum solution for the design according to the system requirements specified. Due to the time to market pressure, the cost of solving the problem of architecture selection by exhaustive analysis is strictly forbidden. The tradeoffs linked to the selection of the appropriate design point during architecture evaluation needs careful assessment for efficient design space exploration. Further DSE requires satisfying multiple conflicting multi objective conditions such as increase in accuracy of evaluation during DSE with simultaneous speedup in the exploration process. This paper presents a novel hybrid design space exploration approach which is a combination of the Priority Factor (PF) method and Fuzzy search technique that is rapid and accurate in architecture evaluation and selection. The proposed approach for DSE when applied on a number of benchmarks yielded superior results compared to the current existing DSE approach for architecture selection. The comparison results of the proposed hybrid approach with the current existing approach for different benchmarks are shown and the speedups obtained are also presented. 相似文献
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Ford Julian D.; Racusin Robert; Daviss William B.; Ellis Cynthia G.; Thomas Julie; Rogers Karen; Reiser Jessica; Schiffman Jill; Sengupta Anjana 《Canadian Metallurgical Quarterly》1999,67(5):786
Consecutive admissions to an outpatient child psychiatry clinic diagnosed with oppositional defiant disorder (ODD), attention deficit-hyperactivity disorder (ADHD), or adjustment disorder were assessed for trauma exposure by a structured clinical interview and parent report. Controlling for age, gender, severity of internalizing behavior problems, social competence, family psychopathology, and parent–child relationship quality (assessed by parent report), an ODD diagnosis, with or without comorbid ADHD, was associated with increased likelihood of prior victimization (but not nonvictimization) trauma. ADHD alone was not associated with an increased likelihood of a history of trauma exposure Traumatic victimization contributed uniquely to the prediction of ODD but not ADHD diagnoses. Children in psychiatric treatment who are diagnosed with ODD, but not those diagnosed solely with ADHD, may particularly require evaluation and care for posttraumatic sequelae. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
59.
Suman Maiti Chandan Chakraborty Sabyasachi Sengupta 《Simulation Modelling Practice and Theory》2009,17(4):585-596
This paper presents a speed estimation technique for the permanent magnet synchronous motor drive. A Model Reference Adaptive System (MRAS) has been formed using the instantaneous and steady-state reactive powers to estimate the speed. It has been shown that such unique MRAS offers several desirable features. The proposed technique is completely independent of stator resistance and is less parameter sensitive, as the estimation-algorithm is only dependent on q-axis stator inductance. Also, the method requires less computational effort as the simplified expressions are used in the MRAS. The stability of the proposed system is achieved through Popov’s Hyperstability criteria. Extensive simulation results are presented to validate the proposed technique. The system is tested at different speeds including zero speed and a very satisfactory performance has been achieved. 相似文献
60.
The pioneering work in the area of millimeter waves, performed by J. C. Bose, a physicist from Calcutta, India, during 1894-1900, is reviewed and appraised. Various measurement techniques and circuit components, developed by him a hundred years ago, are still being used. The development of the electromagnetic horn, the point-contact detector, and the galena (semiconductor) detector of electromagnetic waves are attributed to the original research of J.C. Bose 相似文献