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排序方式: 共有678条查询结果,搜索用时 15 毫秒
101.
Hussein Abdel-Mawgoud Salah Kamel Hegazy Rezk Tahir Khurshaid Sang-Bong Rhee 《计算机、材料和连续体(英文)》2021,69(2):1463-1481
Recently, implementation of Battery Energy Storage (BES) with photovoltaic (PV) array in distribution networks is becoming very popular in overall the world. Integrating PV alone in distribution networks generates variable output power during 24-hours as it depends on variable natural source. PV can be able to generate constant output power during 24-hours by installing BES with it. Therefore, this paper presents a new application of a recent metaheuristic algorithm, called Slime Mould Algorithm (SMA), to determine the best size, and location of photovoltaic alone or with battery energy storage in the radial distribution system (RDS). This algorithm is modeled from the behavior of SMA in nature. During the optimization process, the total active power loss during 24-hours is used as an objective function considering the equality and inequality constraints. In addition, the presented function is based on the probabilistic for PV output and different types of system load. The candidate buses for integrating PV and BES in the distribution network are determined by the real power loss sensitivity factor (PLSF). IEEE 69-bus RDS with different types of loads is used as a test system. The effectiveness of SMA is validated by comparing its results with those obtained by other well-known optimization algorithms. 相似文献
102.
Rejaiba Omar Hcini Fakher Nasri Maria Alzahrani Bandar Bouazizi Mohamed Lamjed Hlil E. K. Khelifi Jabeur Khirouni Kamel Dhahri Essebti 《Journal of Materials Science》2021,56(28):16044-16058
Journal of Materials Science - The CuFeCr0.5Ni0.5O4 (CFO) compound was synthesized using sol–gel reaction combustion technic. The structural analysis showed that the obtained composites have... 相似文献
103.
Channoufi Ines Bourouis Sami Bouguila Nizar Hamrouni Kamel 《Multimedia Tools and Applications》2018,77(19):25591-25606
Multimedia Tools and Applications - In recent years, a great deal of effort has been expended on developing robust solutions for images quality degradation caused mainly by noise. In this paper, we... 相似文献
104.
The advantages of multiparticulate carriers over monolithic one are well known. In this study, mucoadhesive micropellets (MPs) composed of metronidazole (MTZ)–polysaccharide(s) polyelectrolytes complexes were prepared to be used as a localized vaginal healthcare product. The prepared all-natural MPs were characterized using FTIR spectroscopy as well as scanning electron microscopy studies. The MPs were evaluated by determination of drug encapsulation efficiency (EE), particle size (PS), drug release parameters, and ex vivo bioadhesivity using vaginal mucosa. MP-D composed of (MTZ:alginate:polycarbophil?=?1:0.5:0.5) attained the highest EE (97.67%) as well as the most extended drug release properties. Microbiological study comparing MP-D to the market product (Amrizole vaginal suppository) showed the superiority of MP-D by its capability to constantly inhibit fungal growth all-over 24?h, while Amrizole suppository was effective for only 8?h. 相似文献
105.
Integrated ion exchange mixed bed with reverse osmosis and nanofiltration for isolation of neutral dissolved organic matter from natural waters 下载免费PDF全文
Sami Khettaf Kamel‐Eddine Bouhidel Nour el Houda Meguellati Nour el Houda Ghodbane Mohammed Bouhelassa 《Water and Environment Journal》2016,30(3-4):261-270
The aim of this study was to isolate the neutral dissolved organic matter (NDOM) and the low molecular weight neutrals (LMWN) from natural waters. The coupling of an ion exchange mixed bed (IEXMB) with reverse osmosis (RO) and nanofiltration was the main hypothesis. IEXMB removed charged species, while the neutral molecules were isolated in the demineralised water and then concentrated by RO without any osmotic pressure or fouling limits. Neutrals isolation and unlimited concentration, gives this paper its originality. The nanofiltration (NF) step allows for the isolation of the LMWN. The studied reservoir water NDOM and LMWN represented respectively 35% of the dissolved organic matter (DOM) and 34% of the NDOM. Aromatic compounds were found in both fractions. The UV254 absorbance measured before and after the IEXMB evidenced the water quality ‘signature’. IEX has never been studied as fractionation method of DOM. This IEXMB approach is thus quite novel. 相似文献
106.
In this paper, we propose a hybrid classifier fusion scheme for motor unit potential classification during electromyographic (EMG) signal decomposition. The scheme uses an aggregator module consisting of two stages of classifier fusion: the first at the abstract level using class labels and the second at the measurement level using confidence values. Performance of the developed system was evaluated using one set of real signals and two sets of simulated signals and was compared with the performance of the constituent base classifiers and the performance of a one-stage classifier fusion approach. Across the EMG signal data sets used and relative to the performance of base classifiers, the hybrid approach had better average classification performance overall. For the set of simulated signals of varying intensity, the hybrid classifier fusion system had on average an improved correct classification rate (CCr) (6.1%) and reduced error rate (Er) (0.4%). For the set of simulated signals of varying amounts of shape and/or firing pattern variability, the hybrid classifier fusion system had on average an improved CCr (6.2%) and reduced Er (0.9%). For real signals, the hybrid classifier fusion system had on average an improved CCr (7.5%) and reduced Er (1.7%). 相似文献
107.
Palm leaves as a woody lignocellulose, together with polystyrene, were used to produce composites. Chemithermal mechanical pulps (CTMP) were obtained from palm leaves under alkaline or acidic conditions. Appropriate bending strength was obtained from palm leaves and their CTMP pulps prepared under neutral or acidic conditions. The bulky fibers resulted from the alkaline pulps lead to composites of low bending strength. Thus, the cooking conditions of the palm leaves to obtain CTMP pulp play an important role on the properties of the composites. The nonbulky fibers lead to the formation of trapped pockets air as the number of the hydrogen bond are few. The presence of these air pockets allows the polystyrene solution to enter forming bonding between the interfaces. It is also found that the lower the density of the composites, the lower the internal bond strengths. The chemical constituents of the CTMP pulps, as well as the yields of the pulps, may influence the properties of the composites. Increasing the percentage of polystyrene in the composites, the mechanical properties increased. The water uptake and the swellability decreased until 20% polystyrene concentration and then levelled off. The thickness and density behaved the same. However, the type of substrate of the composite and the weight fraction are the important factors in determining the properties of the composites. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 845–855, 1998 相似文献
108.
The ultraviolet (UV) and infrared (IR) spectra of pure poly(vinyl alcohol) (PVA) and gelatin–doped PVA films with concentrations (2, 5, 7, 10, and 15 wt %) were studied before and after irradiation with neutron fluences in the range of 105–108 n/cm2. The obtained data revealed that the addition of gelatin and neutron irradiation causes structural variation in the PVA network. The analysis of the UV spectra showed that the increase of dopant concentration above 5 wt % gelatin makes the sample less resistant to a degradation effect caused by neutron irradiation. It was also found that the intensity of the band at 210 nm increases by increasing dopant concentration. Careful examination of the infrared spectra indicated that the induced percent crystallinity of the sample containing 5 wt % gelatin has more stability than the other doped samples. Neutron irradiation also results in the appearance of new absorption bands and irregular change in the absorbance of some IR bands. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 1395–1406, 1999 相似文献
109.
M. A. Kamel M. A. Abido Moustafa Elshafei 《Intelligent Automation and Soft Computing》2018,24(4):795-805
Directional Steering System (DSS) has been established for well drilling in the oilfield in order to
accomplish high reservoir productivity and to improve accessibility of oil reservoirs in complex
locations. In this paper, a novel feedback linearization controller to cancel the nonlinear dynamics of a
DSS is proposed. The proposed controller design problem is formulated as an optimization problem for
optimal settings of the controller feedback gains. Gravitational Search Algorithm (GSA) is developed to
search for optimal settings of the proposed controller. The objective function considered is to minimize
the tracking error and drilling efforts. In this study, the DSS considered has 4 downhole motors. The
robustness of the proposed GSA-based approach for the controller design is demonstrated. The
simulation results of the considered 4-rotor DSS is presented and the effectiveness of the proposed
controller is confirmed. 相似文献
110.