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41.
42.
Naveed Ahmed Khan Guftaar Ahmad Sardar Sidhu Ahmed Bilal Awan Zain Ali Anzar Mahmood 《国际能源研究杂志》2019,43(13):6721-6739
Microgrids provide promising solution for integration of renewable energy sources in the electrical grid. To exploit the key benefits, achieving the economical operation of renewable aided microgrids has become necessary and is a challenging task. This paper presents an efficient optimization model to minimize the operational cost of a solar integrated microgrid. We formulate a joint optimization mixed integer problem for appropriate modeling of the system under various practical constraints. An efficient solution is obtained with a distributed approach such that the original problem is solved in two stages. Dual decomposition approach is adopted for cost, emissions, and solar share optimization. Lagrange relaxation, Lambda iteration method, and binary integer programming are employed to obtain the joint optimization solution. Finally, the performance of the proposed model is validated through simulations that show that an overall cost reduction of 4.2070e+04 $ and emission reduction of 7.2001e+03 kg are achieved with the proposed model. 相似文献
43.
Wireless Networks - Wireless sensor network (WSN) consists of small sized devices containing different sensors to monitor physical, environmental and medical conditions during surveillance of... 相似文献
44.
Ghulam Gilanie Usama Ijaz Bajwa Mustansar Mahmood Waraich Zulfiqar Habib 《International journal of imaging systems and technology》2019,29(3):260-271
The drive of this study is to develop a robust system. A method to classify brain magnetic resonance imaging (MRI) image into brain-related disease groups and tumor types has been proposed. The proposed method employed Gabor texture, statistical features, and support vector machine. Brain MRI images have been classified into normal, cerebrovascular, degenerative, inflammatory, and neoplastic. The proposed system has been trained on a complete dataset of Brain Atlas-Harvard Medical School. Further, to achieve robustness, a dataset developed locally has been used. Extraordinary results on different orientations, sequences of both of these datasets as per accuracy (up to 99.6%), sensitivity (up to 100%), specificity (up to 100%), precision (up to 100%), and AUC value (up to 1.0) have been achieved. The tumorous slices are further classified into primary or secondary tumor as well as their further types as glioma, sarcoma, meningioma, bronchogenic carcinoma, and adenocarcinoma, which could not be possible to determine without biopsy, otherwise. 相似文献
45.
Yassen Mahmood T. Hussan Mohammed R. Hammas Hussain A. Al-Saedi Hussam Ali Jawad K. 《Wireless Personal Communications》2019,104(2):649-662
Wireless Personal Communications - The design of a fractal based slot antenna, to serve the dual-band communication applications, is proposed in this paper. The structure of the proposed antenna is... 相似文献
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Seyed Jalaledin Najafi Mahmood Mehrdad Shokrieh Ali Akbar Gharehaghaji Seyed Hajir Bahrami 《纺织学会志》2020,111(7):941-949
AbstractElectrospinning of glass nanofibers, as one of the most important techniques for producing nanofibers, was the focus of the present research. This process was done using a carrying polymer in order to modify all important parameters of the process including the solution parameters, the electrospinning voltage, the electrospinning distance and feeding rate of the solution to achieve a desired nanofiber morphology. The produced nanofibers were pyrolyzed at a high temperature to remove the carrying polymer and the FTIR test approved that it was completely removed. The diameter of nanofibers and other details were investigated using SEM images and it was shown that the produced nanofibers have a finer diameter with an average of 228?nm and standard deviation of 46?nm in comparison to other works that reported 500?nm for these characteristics. 相似文献
48.
Amin ZA Abdulla MA Ali HM Alshawsh MA Qadir SW 《Journal of the science of food and agriculture》2012,92(9):1874-1877
BACKGROUND: Recently much attention has been paid to biologically active plants because of their low production cost and fewer adverse effects compared with chemical drugs. In the present investigation the bioactivity of Phyllanthus niruri ethanol and aqueous extracts was evaluated in vitro. RESULTS: The ethanol extract of P. niruri showed a high level of flavonoid content (123.9 ± 0.002 mg g?1), while the aqueous extract showed the highest 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH; IC506.85 ± 1.80 µmol L?1) and 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS; 46.44 ± 0.53 µmol L?1) free radical scavenging activities with high phenol content (376 ± 0.02 mg g?1) and elevated levels of ferric reducing antioxidant power (FRAP; 23 883 ± 0.019 mmol g?1) with excellent antibacterial activity against Staphylococcus aureus (20 mm inhibition zone) and Streptococcus agalactiae (12 mm inhibition zone), respectively, in addition to the best immune activation potential of human peripheral blood mononuclear cells (450.5%). CONCLUSIONS: It is clear from our results that both extracts of P. niruri has excellent bioactivity roles via elevated levels of antibacterial, antioxidant and percentage of peripheral blood mononuclear cell proliferation, which could lead to the development of medications for clinical use. Copyright © 2012 Society of Chemical Industry 相似文献
49.
Maria Yousaf Lodhi Muhammad Azhar Khan Majid Niaz Akhtar Muhammad Farooq Warsi Asif Mahmood Shahid M. Ramay 《Ceramics International》2018,44(3):2968-2975
The influence of neodymium and nickel substitution on structural and dielectric parameters was investigated in strontium-barium X-type hexagonal ferrites having composition SrBaCu2?xNixNdyFe28?yO46 (x = 0, 0.2, 0.4, 0.6, 0.8, 1 and y = 0, 0.02, 0.04, 0.06, 0.08, 0.1). Sol-gel method was employed for synthesizing these hexagonal ferrites. The XRD plots of all studied materials which were annealed at 1250 °C show single phase characteristics. Lattice parameter ‘c’ increased as a consequence of larger radius of rare earth ion (Nd3+) as compared to (Fe3+), while lattice parameter ‘a’ showed very small variation. The cell volume was obtained in the range 2508.32–2523.75 (Å3). The inclusion of Nd-Ni also affected X-ray density, bulk density and porosity. The FTIR spectroscopy indicated the particular absorption peaks of hexagonal ferrites and it was performed in the range of 500–700 cm?1. On account of Nd-Ni doping, the dielectric constant, dielectric loss and AC-conductivity showed decreasing trend. The occupancy of Nd3+ ions at octahedral site impedes the valence alternation of Fe3+; therefore there was decrease in dielectric permittivity. Ac conductivity has been decreased from 9.14 to 6.49 (Ω cm)?1 at frequency of 2.7 GHz. The Cole-Cole plots of synthesized materials noticeably revealed grain boundary contribution. The appearance of single semi-circle in impedance Cole-Cole graphs confirms the exceptional role of grain boundaries in the conduction process. The considerably lower dielectric parameters of investigated nano X-type ferrites propose their feasibility for high-frequency applications (phase shifters, dielectric resonators, stealth technology etc). 相似文献
50.
Rai Muhammad Sarfraz Mahmood Ahmad Asif Mahmood Hira Ijaz 《Polymer-Plastics Technology and Engineering》2018,57(12):1175-1187
Current research work was conducted for enhancing solubility of rosuvastatin calcium. A highly stable, biocompatible, and nontoxic β-cyclodextrin-g-poly(methacrylic acid) graft polymeric network was developed. Formulations proved entrapment efficacy (%) in between 82.30?±?0.25 and 89.00?±?0.25 and gel fraction between 90.34?±?1.012 and 95.25?±?1.331. Formulation HM2 had shown optimum swelling and drug release, i.e., 85.74% at pH 6.8. The best-fit model was first-order kinetics with anomalous diffusion as release mechanism. Likewise, solubility enhancement, i.e., 9.59-folds was determined at pH 6.8. It was concluded that hydrogel microparticles are the promising tools for improving solubility and bioavailability of hydrophobic drugs. 相似文献