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MEMS-Based Wireless Communications
Published in Anwar Sohail, Raja M Yasin Anwar Akhtar, Raja Qazi Salahuddin, Ilyas Mohammad, Nanotechnology for Telecommunications, 2017
The capacitor can be tuned by varying one of three parameters such as distance between the electrode, area, or dielectric of the material. It can be classified as gap tuning, area tuning, or dielectric tuning. Gap and area tuning is commonly used by employing electrostatic or thermal actuation.
Review on the synthesis, performance and trends of butanol: a cleaner fuel additive for gasoline
Published in International Journal of Ambient Energy, 2022
Toxic emissions and performance of SI engine using iso-butanol – gasoline blends (3, 7 and 10 vol. % iso-butanol with neat gasoline) has been studied by Elfasakhany (2016). A single-cylinder four-stroke SI engine was used at speed range of 2600–3400 r/min. CO and unburned HC emissions of pure gasoline are higher than blends at speeds equal to or less than 2900 r/min but at higher speed, the results were just the opposite. The carbon dioxide emission however was found to be the always less for the blend. There was a drop in engine performance on using blends within all speeds without any engine modification. However, when suitable engine tuning was done, better combustion, higher performance and lesser emissions were observed. The study also concludes that iso-butanol gasoline blend gives less CO and CO2 emission and higher performance compared to n-butanol which however gave lower unburned HC emissions. Thus the blends bring about a considerable decrease in emissions at low speeds without compromising much on the engine performance is what is concluded by the author.
GPU parameter tuning for tall and skinny dense linear least squares problems
Published in Optimization Methods and Software, 2020
Benjamin Sauk, Nikolaos Ploskas, Nikolaos Sahinidis
Optimal tuning parameters are desirable as they can lead to significant performance benefits. For example, well chosen parameters have led to a 25% increase in performance compared to default parameter values in the case of matrix-matrix multiplication [44]. This paper investigates the potential of using DFO and SO solvers to tune GPU algorithms for LLSPs. The idea of using DFO algorithms to tune algorithms is not new. Audet and Orban [11] proposed a DFO approach to tune a trust-region method. By using DFO and SO solvers to determine optimal tuning parameters for solving LLSPs with GPUs, the primary contributions of this paper are as follows: We provide a computational comparison of DFO and SO algorithms, thus adding to a recently emerging literature on comparisons of DFO algorithms that is still in its infancy [59] and helps increase our understanding of the capabilities of these solvers.We show that it is possible to accelerate MAGMA's QR solver by a factor of 1.8 for large TS matrices compared to the MAGMA algorithm with its default parameters.We demonstrate that a specific collection of five DFO solvers is capable of finding optimal GPU parameters and that it succeeds in doing so while requiring an order of magnitude fewer function evaluations than complete enumeration.We demonstrate that the best DFO solvers are able to identify higher quality solutions faster than OpenTuner [9].