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排序方式: 共有478条查询结果,搜索用时 15 毫秒
1.
A robust model-free controller for a three-phase grid-connected photovoltaic system based on ultra-local model 下载免费PDF全文
In this paper, a robust model-free controller for a grid-connected photovoltaic (PV) system is designed. The system consists of a PV generator connected to a three-phase grid by a DC/AC converter. The control objectives of the overall system are to extract maximum power from the PV source, to control reactive power exchange and to improve the quality of the current injected into the grid. The model-free control technique is based on the use of an ultra-local model instead of the dynamic model of the overall system. The local model is continuously updated based on a numerical differentiator using only the input–output behavior of the controlled system. The model-free controller consists of a classical feedback controller and a compensator for the effects of internal parameter changes and external disturbances. Simulation results illustrate the efficiency of the controller for grid-connected PV systems. 相似文献
2.
Salim Hengky K. Padfield Rory Lee Chew Tin Syayuti Khadijah Papargyropoulou Effie Tham Mun Hou 《Clean Technologies and Environmental Policy》2018,20(3):529-538
Clean Technologies and Environmental Policy - Food production and consumption is one of the major causes of global environmental degradation. One way to address environmental impacts in the food... 相似文献
3.
A. Djellouli K. Benyelloul H. Aourag S. Bekhechi A. Adjadj Y. Bouhadda O. ElKedim 《International Journal of Hydrogen Energy》2018,43(41):19111-19120
In this paper, two techniques of datamining tools were adopted, a principal component analysis (PCA) and artificial neural network (ANN). A PCA to classify, select and identify several combinations between transition element A and B (B = Ti, Zr, Hf, Sc, Y, La and Th) and ANN to predict ΔH for ternary hydrides. Based on the datasets selected from different works, a principal component analysis (PCA) has been applied to select, classify and identify around 76 possible combinations between transition metal elements A and B. The results showed that the clustering of combinations A-B are significantly influenced by the atomic parameters of element A, such atomic radius (RA), Pauling's electronegativity (χA) and atomic electron density (ZA/RA3). From 76 combinations, 55 systems which have χA ≥ 1.5, ZA/RA3>1.28 and RA < 1.46 Å are categorized as group 1. On the other hand, 21 systems which have χA < 1.5, ZA/RA3 < 1.28, and RA > 1.46 Å are categorized as group 2. From the first group, 46 different combinations are identified and have a negative ΔH, within 18 well-known promising binary alloys of hydrogen storage.An (6-15-1) architecture of artificial neural network (ANN) has been developed to estimate the ΔH for the other ternary hydrides selected from different published works. The performance indices such as relative error, coefficient of determination (R2) and mean square error (MSE) were used to control the performance of obtained results. In addition to this, the ΔH obtained from ANN model were compared with those experimental data and theoretical results available in the literature. 相似文献
4.
Imdad Ali Salim Saifullah Babiker M. El-Haj Heyam Saad Ali Saira Yasmeen Muhammad Imran Jan Nisar Muhammad Raza Shah 《Journal of surfactants and detergents》2020,23(5):973-980
Nonionic surfactants are highly stable and cost-effective and receiving acceptance for applications in many diverse fields including drug delivery, due to their distinctive properties. Here, we report on the synthesis and characterization of sulfanilamide-based nonionic surfactants for nanoscale vesicular drug loading applications. Nonionic surfactants were synthesized through alkylation of sulfanilamide with alkyl halides that possessed diverse degrees of lipophilicity. They were explored for their nanovesicular drug loading with Cefixime as a hydrophobic model drug. Drug-loaded nanovesicles were characterized for surface morphologies, size, size distribution, surface charge, and drug loading efficiency using atomic force microscopy (AFM), dynamic light scattering (DLS), and UV–visible spectrophotometry. All of the synthesized nonionic surfactants revealed their CMC values in 0.055–0.035 mM range depending upon the lipophilic chain length of surfactants. They caused a decreased hemoglobin release and low toxicity against cell culture. They self-assembled and loaded an increased amount of drug in the form of nanorange spherical shape niosomal vesicles. Results of the current study verify these synthesized nonionic surfactants are hemocompatible, nontoxic, and capable of self-assembling into nanorange niosomal vesicles. These niosomal vesicles can be suggested as safe and highly efficient nanocarriers for hydrophobic drug loading and delivery. 相似文献
5.
Zouaidia Khouloud Ghanemi Salim Rais Mohamed Saber Bougueroua Lamine Katarzyna Wgrzyn-Wolska 《Neural computing & applications》2021,33(23):16591-16608
Neural Computing and Applications - Nowadays wind power is considered as one of the fastest growing alternative energies, that is expected to continue to grow rapidly in the upcoming... 相似文献
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Sofie Zarina Lamaming Junidah Lamaming Nurul Fazita Mohammad Rawi Rokiah Hashim Mohamad Haafiz Mohamad Kassim Mohd Hazwan Hussin Yazmin Bustami Othman Sulaiman Mohd Hazim Mohamad Amini Salim Hiziroglu 《Polymer Engineering and Science》2021,61(10):2393-2405
Soy protein is known for its eco-friendly, sustainable, and biodegradable qualities that are likely used as raw material in producing bioadhesive. However, soy protein-based adhesive are lacking in terms of adhesive strength and water-resistance compared to commercial formaldehyde-based adhesives such as phenol and urea-formaldehyde resin. Therefore, continuous research has been done to improve adhesive performance. This can be done via physical or modification methods, including the usage of cross-linking agents, structural modification, enzymatic modification, and the addition of additives. This review will cover these modification methods that give significant enhancement to the water-resistance and adhesive strength of soy protein-based adhesives. 相似文献
9.
In this study some of the important properties of experimentally manufactured wood–plastic composites (WPC) were determined. Specimen having 60% and 80% particle and fiber of radiata pine (Pinus radiata ) were mixed with polypropylene (plastic) and four different additives, namely Structor TR 016 which is coupling agent, CIBA anti-microbial agent (IRGAGUARD F3510) as fungicide, CIBA UV filter coating (TINUVIN 123S), CIBA blue pigment (Irgalite), and their combinations. Based on the initial finding of this work static bending properties of the samples enhanced as above chemicals were added into both particle and fiber-based specimens. Thickness swelling of the samples were also improved with having additives in the panels. Micrographs taken on scanning electron microscope (SEM) revealed that coupling agent and pigment resulted in more homogeneous mixture of wood and plastic together. Two surface roughness parameters average roughness (Ra) and maximum roughness (Rmax) used to evaluate surface characteristics of the samples showed that particle based samples had rougher surface characteristics than those of fiber based ones. No significant influence of chemicals added in the samples was found on surface roughness values of the samples manufactured from particle and fiber of radiata pine. 相似文献