The Experts below are selected from a list of 291 Experts worldwide ranked by ideXlab platform
Mostafa Ammar - One of the best experts on this subject based on the ideXlab platform.
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Optimal reDesign policies to support dynamic processing of applications on a distributed relational database system
Information Systems, 1996Co-Authors: Kamalakar Karlapalem, Shamkant B. Navathe, Mostafa AmmarAbstract:An application processing center consists of a set of well-defined, well-Designed and well-tested applications that are dynamically executed over a period of time. We assume that there is a set of Candidate distributed database Designs each of which is optimal for some applications. The random execution of applications on a distributed database Design is modeled as a discrete Markov process, and the problem of selecting the Candidate Design for each execution of an application is solved by using Sequential Markovian Decision Process analysis to generate an optimal reDesign policy vector. The scope of the methodology developed in this paper is applicable to environments similar to application processing centers. The viability of this methodology is illustrated by means of a case study conducted at Georgia Institute of Technology.
Kamalakar Karlapalem - One of the best experts on this subject based on the ideXlab platform.
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Optimal reDesign policies to support dynamic processing of applications on a distributed relational database system
Information Systems, 1996Co-Authors: Kamalakar Karlapalem, Shamkant B. Navathe, Mostafa AmmarAbstract:An application processing center consists of a set of well-defined, well-Designed and well-tested applications that are dynamically executed over a period of time. We assume that there is a set of Candidate distributed database Designs each of which is optimal for some applications. The random execution of applications on a distributed database Design is modeled as a discrete Markov process, and the problem of selecting the Candidate Design for each execution of an application is solved by using Sequential Markovian Decision Process analysis to generate an optimal reDesign policy vector. The scope of the methodology developed in this paper is applicable to environments similar to application processing centers. The viability of this methodology is illustrated by means of a case study conducted at Georgia Institute of Technology.
A. N. Otte - One of the best experts on this subject based on the ideXlab platform.
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Status of the Schwarzchild-Couder medium-sized telescope for the Cherenkov telescope array
2017Co-Authors: W. Benbow, A. N. OtteAbstract:The Cherenkov Telescope Array (CTA) is planned to be the next-generation very-high-energy (VHE; E>100 GeV) gamma-ray observatory. It is anticipated that CTA will improve upon the sensitivity of the current generation of VHE experiments, such as VERITAS, HESS and MAGIC, by an order of magnitude. CTA is planned to consist of two graded arrays of Cherenkov telescopes with three primary-mirror sizes. A proof-of-concept telescope, based on the dual-mirror Schwarzchild-Couder Design, is being constructed on the VERITAS site at the F.L. Whipple Observatory in southern Arizona, USA, and is a Candidate Design for the medium-sized telescopes. The telescope’s construction will be completed in early 2017, and the status of this project is presented here.
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Status of the Schwarzchild-Couder Medium-Sized Telescope for the Cherenkov Telescope Array
arXiv: Instrumentation and Methods for Astrophysics, 2016Co-Authors: W. Benbow, A. N. OtteAbstract:The Cherenkov Telescope Array (CTA) is planned to be the next-generation very-high-energy (VHE; E > 100 GeV) gamma-ray observatory. It is anticipated that CTA will improve upon the sensitivity of the current generation of VHE experiments, such as VERITAS, HESS and MAGIC, by an order of magnitude. CTA is planned to consist of two graded arrays of Cherenkov telescopes with three primary-mirror sizes. A proof-of-concept telescope, based on the dual-mirror Schwarzchild-Couder Design, is being constructed on the VERITAS site at the F.L. Whipple Observatory in southern Arizona, USA, and is a Candidate Design for the medium-sized telescopes. The construction of the telescope will be completed in early 2017, and the status of this project is presented here.
Arun S. Mujumdar - One of the best experts on this subject based on the ideXlab platform.
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Application of phase change materials in thermal management of electronics
Applied Thermal Engineering, 2007Co-Authors: Ruckmani Kandasamy, Xiang Qi Wang, Arun S. MujumdarAbstract:Application of a novel PCM package for thermal management of portable electronic devices was investigated experimentally for effects of various parameters e.g. power input, orientation of package, and various melting/freezing times under cyclic steady conditions. Also, a two-dimensional numerical study was made and compared the experimental results. Results show that increased power inputs increase the melting rate, while orientation of the package to gravity has negligible effect on the thermal performance of the PCM package. The thermal resistance of the device and the power level applied to the PCM package are of critical importance for Design of a passive thermal control system. Comparison with numerical results confirms that PCM-based Design is an excellent Candidate Design for transient electronic cooling applications.
Yaochu Jin - One of the best experts on this subject based on the ideXlab platform.
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CEC - Hierarchical Surrogate-Assisted Evolutionary Multi-Scenario Airfoil Shape Optimization
2018 IEEE Congress on Evolutionary Computation (CEC), 2018Co-Authors: Handing Wang, John Doherty, Yaochu JinAbstract:For multi-scenario airfoil shape optimization problems, an evaluation of a single airfoil is based on its full-scenario drag landscape. To obtain the full-scenario drag landscape, a large number of computational fluid dynamic simulations for different operating conditions must be conducted. Since a single computational fluid dynamic simulation is often time-consuming, evaluations for multi-scenario airfoil shape optimization will be computationally highly intensive. Although surrogate-assisted evolutionary algorithms have been widely applied to expensive optimization problems, existing surrogate-assisted evolutionary algorithms cannot be directly applied to multi-scenario airfoil shape optimization due to the lack of training data. Instead of using surrogate models to directly approximate the multi-scenario evaluations, we employ a hierarchical surrogate model consisting of a K-nearest neighbors classifier and a Kriging model to approximate the full-scenario drag landscape for each Candidate Design during the optimization. Then, the fitness of the Candidate Design is evaluated based on the approximated drag landscape to reduce the computational cost. The proposed hierarchical surrogate model is embedded in the covariance matrix adaptation evolution strategy and applied to the RAE2822 airfoil Design problem. Our experimental results show that the proposed algorithm is able to obtain an airfoil Design with limited computational cost that perform well in different operating conditions.
