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Experimental and CFD Study on the Role of Fluid Flow Pattern on Membrane Permeate Flux 被引量:7
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作者 A. Parvareh M. Rahimi +1 位作者 S. S. Madaeni A. A. Alsairafi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第1期18-25,共8页
这份报纸在实验室规模通过微过滤膜在 permeate 流动上在液体流动模式和动态压力的角色上报导研究。为这个目的,与海洋的类型 impeller 装备的一个尽头的膜房间被使用。impeller 被设置旋转在顺时针方向并且顺时针方向与一样的尖速度... 这份报纸在实验室规模通过微过滤膜在 permeate 流动上在液体流动模式和动态压力的角色上报导研究。为这个目的,与海洋的类型 impeller 装备的一个尽头的膜房间被使用。impeller 被设置旋转在顺时针方向并且顺时针方向与一样的尖速度阻止方向以便说明旋转方向的效果在上渗入流动。因而,渗入流动在各种各样的 impeller 被测量旋转速度。计算液体动力学(CFD ) 预言动态压力与在实验获得的流动有关。用当模特儿的 CFD,在在膜表面之上的动态压力的变化在 permeate 流动上有直接效果,这被证明。 展开更多
关键词 实验室规模 CFD建模 膜通量 内流场 渗透通量 动态压力 流体流动模式 计算流体力学
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An Effective Runge-Kutta Optimizer Based on Adaptive Population Size and Search Step Size
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作者 Ala Kana Imtiaz Ahmad 《Computers, Materials & Continua》 SCIE EI 2023年第9期3443-3464,共22页
A newly proposed competent population-based optimization algorithm called RUN,which uses the principle of slope variations calculated by applying the Runge Kutta method as the key search mechanism,has gained wider int... A newly proposed competent population-based optimization algorithm called RUN,which uses the principle of slope variations calculated by applying the Runge Kutta method as the key search mechanism,has gained wider interest in solving optimization problems.However,in high-dimensional problems,the search capabilities,convergence speed,and runtime of RUN deteriorate.This work aims at filling this gap by proposing an improved variant of the RUN algorithm called the Adaptive-RUN.Population size plays a vital role in both runtime efficiency and optimization effectiveness of metaheuristic algorithms.Unlike the original RUN where population size is fixed throughout the search process,Adaptive-RUN automatically adjusts population size according to two population size adaptation techniques,which are linear staircase reduction and iterative halving,during the search process to achieve a good balance between exploration and exploitation characteristics.In addition,the proposed methodology employs an adaptive search step size technique to determine a better solution in the early stages of evolution to improve the solution quality,fitness,and convergence speed of the original RUN.Adaptive-RUN performance is analyzed over 23 IEEE CEC-2017 benchmark functions for two cases,where the first one applies linear staircase reduction with adaptive search step size(LSRUN),and the second one applies iterative halving with adaptive search step size(HRUN),with the original RUN.To promote green computing,the carbon footprint metric is included in the performance evaluation in addition to runtime and fitness.Simulation results based on the Friedman andWilcoxon tests revealed that Adaptive-RUN can produce high-quality solutions with lower runtime and carbon footprint values as compared to the original RUN and three recent metaheuristics.Therefore,with its higher computation efficiency,Adaptive-RUN is a much more favorable choice as compared to RUN in time stringent applications. 展开更多
关键词 Optimization Runge Kutta(RUN) metaheuristic algorithm exploration EXPLOITATION population size adaptation adaptive search step size
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Comparative analysis on the performance of different types of input-and command-shaping controllers in minimizing payload residual vibration of an overhead crane with an inclined supporting track
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作者 Mohammed Alfares Khaled Alhazza 《International Journal of Mechanical System Dynamics》 EI 2024年第1期22-33,共12页
Reducing the effects of external disturbance on overhead crane systems is crucial,as they can impair the controller performance and cause excessive vibrations or oscillations of the payloads.One such external disturba... Reducing the effects of external disturbance on overhead crane systems is crucial,as they can impair the controller performance and cause excessive vibrations or oscillations of the payloads.One such external disturbance is the inclination of the supporting track of the crane trolley,which causes the system dynamics model to change.An open-loop control strategy is widely utilized to control the payload sway motion and generally does not require any alterations in the physical structure of a system or the installation of sensors and/or actuators.Input and command shaping are two common open-loop control techniques applied to control overhead cranes.In this paper,the effect of moving an overhead crane system along an inclined supporting track is investigated.In addition,the ability of different types of input-and command-shaping control schemes to suppress the residual vibrations due to trolley track inclination is demonstrated.Two types of input-shaping controllers,which are double-step,zero vibration,and one command waveform(WF)shaper based on a trigonometric function,are used and tested.A linear equation of motion of the overhead crane resting on an inclined surface is developed to simulate the overhead crane and payload motion.The effectiveness of the different types of open-loop controllers to suppress residual vibrations is verified by both simulation and experimental results.In addition,a new WF command shaper is proposed and designed to overcome track inclination while eliminating payload residual vibration.A comprehensive comparative analysis,both numerically and experimentally,is performed on the new proposed shaper to measure its effectiveness in handling inclination when compared to other types of open-loop controllers.The new shaper outperforms other controllers in eliminating payload residual vibration for a wider range of inclination angles. 展开更多
关键词 overhead cranes open-loop control input and command shaping payload residual vibrations
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Designs of Two-Element Optical Refracting System to Achieve Uniform Laser Beam Profile
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作者 Abdallah K. Cherri Nabil I. Khachab Mahmoud K. Habib 《Journal of Applied Mathematics and Physics》 2017年第12期2371-2385,共15页
Various specific laser irradiance distribution outputs are needed in many applications. To fulfill this need, a detailed step-by-step design procedure for split refracting system is proposed for three types of laser b... Various specific laser irradiance distribution outputs are needed in many applications. To fulfill this need, a detailed step-by-step design procedure for split refracting system is proposed for three types of laser beams transformation: 1) Annular-uniform-to-uniform;2) Annular-Gaussian-to-uniform;and 3) Gaussian-to-uniform to obtain the required laser irradiance distributions. Mathematical expressions of the two Plano-aspheric surfaces are derived for each type. The proposed designs take into account few important parameters such as the system length, the surfaces radii of curvature, the annular beam starting cone angle, and the beams power ratio. Further, the proposed designs are much better than the ones, which were previously 展开更多
关键词 ANNULAR Laser Beam Refracting SYSTEM LENS Design
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Experimentation with Personal Identifiable Information 被引量:3
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作者 Sabah Al-Fedaghi Abdul Aziz Rashid Al-Azmi 《Intelligent Information Management》 2012年第4期123-133,共11页
In this paper, actual personal identifiable information (PII) texts are analyzed to capture different types of PII sensitivities. The sensitivity of PII is one of the most important factors in determining an individua... In this paper, actual personal identifiable information (PII) texts are analyzed to capture different types of PII sensitivities. The sensitivity of PII is one of the most important factors in determining an individual’s perception of privacy. A “gradation” of sensitivity of PII can be used in many applications, such as deciding the security level that controls access to data and developing a measure of trust when self-disclosing PII. This paper experiments with a theoretical analysis of PII sensitivity, defines its scope, and puts forward possible methodologies of gradation. A technique is proposed that can be used to develop a classification scheme of personal information depending on types of PII. Some PII expresses relationships among persons, some specifies aspects and features of a person, and some describes relationships with nonhuman objects. Results suggest that decomposing PII into privacy-based portions helps in factoring out non-PII information and focusing on a proprietor’s related information. The results also produce a visual map of the privacy sphere that can be used in approximating the sensitivity of different territories of privacy-related text. Such a map uncovers aspects of the proprietor, the proprietor’s relationship to social and physical entities, and the relationships he or she has with others. 展开更多
关键词 PERSONAL Identifiable INFORMATION PUBLIC POLICY Issues PRIVACY Sensitivity
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Multiple Targets Recognition for Highly-Compressed Color Images in a Joint Transform Correlator
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作者 Abdallah K. Cherri Alshahd S. Nazar 《Optics and Photonics Journal》 2022年第5期107-127,共21页
In this paper, we are proposing a compression-based multiple color target detection for practical near real-time optical pattern recognition applications. By reducing the size of the color images to its utmost compres... In this paper, we are proposing a compression-based multiple color target detection for practical near real-time optical pattern recognition applications. By reducing the size of the color images to its utmost compression, the speed and the storage of the system are greatly increased. We have used the powerful Fringe-adjusted joint transform correlation technique to successfully detect compression-based multiple targets in colored images. The colored image is decomposed into three fundamental color components images (Red, Green, Blue) and they are separately processed by three-channel correlators. The outputs of the three channels are then combined into a single correlation output. To eliminate the false alarms and zero-order terms due to multiple desired and undesired targets in a scene, we have used the reference shifted phase-encoded and the reference phase-encoded techniques. The performance of the proposed compression-based technique is assessed through many computer simulation tests for images polluted by strong additive Gaussian and Salt & Pepper noises as well as reference occluded images. The robustness of the scheme is demonstrated for severely compressed images (up to 94% ratio), strong noise densities (up to 0.5), and large reference occlusion images (up to 75%). 展开更多
关键词 Image Compression JPEG Image Format Multiple Targets Detection Fringe-Adjusted Joint Transform Correlation Random-Phase Mask
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Physics-based electrical modelling of CIGS thin-film photovoltaic modules for system-level energy yield simulations
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作者 Santhosh Ramesh Arttu Tuomiranta +3 位作者 Ali Hajjiah Marc Meuris Bart Vermang Jef Poortmans 《npj Flexible Electronics》 SCIE 2022年第1期854-862,共9页
Copper indium gallium selenide(CIGS)is a commercialized,high-efficiency thin-film photovoltaic(PV)technology.The state-of-theart energy yield models for this technology have a significant normalized root mean square e... Copper indium gallium selenide(CIGS)is a commercialized,high-efficiency thin-film photovoltaic(PV)technology.The state-of-theart energy yield models for this technology have a significant normalized root mean square error(nRMSE)on power estimation:De Soto model—26.7%;PVsyst model—12%.In this work,we propose a physics-based electrical model for CIGS technology which can be used for system-level energy yield simulations by people across the PV value chain.The model was developed by considering models of significant electrical current pathways from literature and adapting it for the system-level simulation.We improved it further by incorporating temperature and irradiance dependence of parameters through characterisation at various operating conditions.We also devised a module level,non-destructive characterization strategy based on readily available measurement equipment to obtain the model parameters.The model was validated using the measurements from multiple commercial modules and has a significantly lower power estimation nRMSE of 1.2%. 展开更多
关键词 CIGS ELECTRICAL PVsyst
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