We investigate that resource provisioning and scheduling is a prominent problem due to heterogeneity as well as dispersion of cloud resources. Cloud service providers are building more and more datacenters due to demand of high computational power which is a serious threat to environment in terms of energy requirement. To overcome these issues, we need an efficient meta-heuristic technique that allocates applications among the virtual machines fairly and optimizes the quality of services (QoS) parameters to meet the end user objectives. Binary particle swarm optimization (BPSO) is used to solve real-world discrete optimization problems but simple BPSO does not provide optimal solution due to improper behavior of transfer function. To overcome this problem, we have modified transfer function of binary PSO that provides exploration and exploitation capability in better way and optimize various QoS parameters such as makespan time, energy consumption, and execution cost. The computational results demonstrate that modified transfer function-based BPSO algorithm is more efficient and outperform in comparison with other baseline algorithm over various synthetic datasets.
In this paper, a fully non-conforming least-squares spectral element method for fourth order elliptic problems on smooth domains is presented. The proposed method works for a general fourth order elliptic operator with non-homogeneous data in two dimensions and gives exponentially accurate solutions. We derive differentiability estimates and prove our main stability estimate theorem using a non-conforming spectral element method. We then formulate a numerical scheme using a block diagonal preconditioner. Error estimates are also proven for the proposed method. We provide the computational complexity of our method and present results of numerical simulations that have been performed to validate the theory. 相似文献
This article reports a comparative study of two artificial neural network structures and associated variants used to describe and predict the behavior of 2 × 200 μm2 GaN high electron mobility transistors (HEMTs), utilizing radiofrequency characterization. Two architectures namely multilayer perceptron and cascade feedforward, have been investigated in this work to develop the behavioral model. A study is conducted utilizing the two architectures, all trained using Levenberg‐Marquardt, in terms of accuracy, convergence rate, and generalization capability to develop the behavioral model of GaN HEMT. However, to ensure the robustness of the model, accuracy, convergence rate, time elapsed, and generalization capability of the proposed model is also tested under couple of training algorithms, activation functions, number of hidden layers and neuron embedded inside it, methods for initialization of weights and bias and certain other vital parameters playing vital role in influencing the model accuracy and effectiveness. An excellent agreement found between measured S‐parameters and the proposed model proves the effectiveness of the proposed approach and excellent prediction ability for a sweeping multibias set and broad frequency range of 1 to 18 GHz. Moreover, a very good generalization capability is also recorded under variation of crucial parameters of GaN HEMT‐based neural model. 相似文献
Potassium, electrochemically supplied from K β"‐alumina to a silver thin film catalyst in the presence of ppm levels of NOx, strongly promotes the selectivity of ethene epoxidation. However, in the absence of gaseous NOx, alkali catastrophically suppresses both activity and selectivity. Addition of surface chlorine via ppm levels of ethylene
dichloride further enhances the promotional effect of alkali + NO yielding the highest selectivity of all. The minimum necessary
and sufficient conditions for the appearance of NOx promotion are submonolayer quantities of alkali on the metal surface, and ppm levels of gaseous NOx.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
The reaction of 3-mercaptopropan-l,2-diol with methyl 10-undecenoate (Ib) yielded three products, methyl 11-(3′-mercaptopropan-l′,2′-diacetoxy)
undecanoate (II, 48.9%), methyl 11-(1-oxapropan-2′-acetoxy-3′-mercaptoacetyl) undecanoate (III, 27.4%) and methyl 10-(3′-mercaptopropan-1′-acetoxy-2′-ol) undecanoate (IV, 23.0%) along with hydrolyzed starting material
(Ia, 5.4%). The same reaction with methyl 9-octadecenoate (Vb) gave an isomeric product, 9(10)-(3′-mercaptopropan-l′-acetoxy-2′-ol)
octadecanoic acid (VI, 78.5%) and oleic acid (Va, 21.4%). Reaction withtrans-2-octadecenoic acid (VII) afforded 2(3)-(3′-mercaptopropan-l′-acetoxy-2′-ol) octadecanoic acid (VIII, 85.7%). 相似文献
This paper presents the relative gain analysis of two industrial distillation columns. Both columns involve multicomponent separation and the purpose of the relative gain analysis has been to find proper pairing of manipulated and controlled variables. The matrix oriented method of Wang and Henke has been employed in the study, The study has investigated the effects of single-precision versus double-precision programming, step-size, and tightness of convergence, upon the relative gain array. The results with single-precision programming and double-precision programming have yielded significantly different results. The results confirm that a considerable reduction in the step-size of the manipulated variables may be necessary in some cases to achieve meaningful results. They also indicate that tight convergence may be required for some columns at a considerable expense in terms of CPU time while for others, loose convergence and moderate step-sizes may be adequate, The results of this study will be useful to those who are interested in the design of distillation control systems. 相似文献
An experimental investigation of the kinetics of bulk thermal polymerization of styrene in the temperature range of 200°–230°C is reported. Conversions and molecular weight averages were measured by gel permeation chromatography. At elevated temperatures, oxygen in the polymerization mixture appears to have negligible effect on the rate of polymerization and the molecular weights of the polymer. Experimental evidence suggests that the molecular weight development of the polymer is strongly influenced by transfer reactions. 相似文献
The goal of this paper is to study the feasibility of making intelligent antenna selection decision in IEEE 802.15.4 Wireless Sensor Networks (WSNs). This study provides us the basis to design and implement software defined intelligent antenna switching capability to wireless sensor nodes based on Received Signal Strength Indicator (RSSI) link quality metric. First, we discuss the results of our newly designed radio module (Inverted-F Antenna) for 2.4 GHz bandwidth (WSNs). Second, we propose an intelligent antenna selection strategy to exploit antenna diversity. Third, we propose the prototype of our diversity antenna for the TelosB mote and the intelligent switch design. Finally, we compare the performance of the built-in TelosB antenna with our proposed external antenna in both laboratory and realistic environments. Experimental results confirm the gain of 6–10 dB of the proposed radio module over the built-in radio module of the TelosB motes. 相似文献
In an isothermal fixed bed absorption system for constant inlet flowrate of inert gas and concentrations of two adsorbates the more strongly adsorbed component will displace the weaker one and effect its breakthrough characteristics. A small scale technique was used to study this phenomenon for the adsorption of water vapour and carbon dioxide on 4A type synthetic zeolites with helium as the carrier gas. Single adsorbate equilibria and rate data determined with the binary mixtures were then used to calculate the results for the ternary one. Partial differential equations were derived to describe the mass transfer of each adsorbate based on pore diffusion in the adsorbent as a major rate controlling mechanism. With a simplified binary Langmuir equilibrium to describe the effect of water on the adsorption of carbon dioxide, and assuming that the effective pore diffusion coefficient of one adsorbate was not affected by the presence of the other, accurate predictions of the concentration transient were obtained. Four zones are formed in the bed with the ternary mixture resulting from the desorption of carbon dioxide by water, the concentrations of the former rising above the inlet value. An enhanced rate of adsorbed phase transport of water was found, additional to that expected from macropore diffusion, suggesting that surface or capillary flow of the adsorbate occurred. 相似文献