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101.
Amir Rastegarnia Mohammad Ali Tinati Azam Khalili 《Signal, Image and Video Processing》2013,7(2):227-234
In this paper, we analyze the steady-state performance of the distributed incremental least mean-square (DILMS) algorithm when it is implemented in finite-precision arithmetic. Our analysis in this paper does not consider any distribution of input data. We first formulate the update equation for quantized DILMS algorithm, and then we use a spatial-temporal energy conservation argument to derive theoretical expressions that evaluate the steady-state performance of individual nodes in the network. We consider mean-square error, excess mean-square error, and mean-square deviation as the performance criteria. Simulation results are generated by using two types of signals, Gaussian and non-Gaussian distributed signals. As the simulation results show, there is a good match between the theory and simulation. 相似文献
102.
Seyed‐Ataollah Mirshafiei‐Langari Vahid Haddadi‐Asl Hossein Roghani‐Mamaqani Masoud Sobani Khezrollah Khezri 《Polymer Composites》2013,34(10):1648-1654
Polystyrene nanocomposite with mixed free and anchored chains was synthesized by atom transfer radical polymerization. Attachment of 3‐(trimethoxysilyl)propyl methacrylate with a double bond on the nanoporous silica aerogel surface results in a double bond grafted silica aerogel which could be incorporated into the polystyrene chains by a grafting‐through process. Conversion and molecular weight evaluation was carried out using gas chromatography and gel permeation chromatography, respectively. Double bond containing silica aerogel has an inconsiderable effect on conversion. There is no considerable discrepancy between the molecular weights of the free and anchored chains. Addition of silica aerogel with pendant CC bonds leads to increase of apparent rate constant of polymerization and also molecular weights. This is mainly because of initiator trapping in silica aerogel pores. Every percent of double bond containing silica aerogel with respect to styrene results in trapping of about 0.08 mol of ethyl alpha‐bromoisobutyrate among the silica pores. POLYM. COMPOS., 34:1648–1654, 2013. © 2013 Society of Plastics Engineers 相似文献
103.
Azam Beg 《International Journal of Electronics》2013,100(7):1120-1131
In this paper, we present a multi-objective optimisation technique for transistor sizing in the variation-prone nanometric complementary metal-oxide semiconductor (CMOS) logic cells. To demonstrate the effectiveness of the technique, we have used the common figures-of-merit, such as power, energy, and static noise margin. By using examples of different logic cells, we have demonstrated how competing design goals can be tackled effectively. We show that concurrent improvements in multiple figures-of-merit are possible using the proposed method. 相似文献
104.
M. Azam Ali M. A. Khan K. M. Idriss Ali 《Polymer-Plastics Technology and Engineering》2013,52(5):663-678
Polymeric films were prepared under UV radiation with tetraacrylated urethane oligomer in combination with N-vinyl pyrrolidone (NVP) using a set of four photoinitiators (Irg 907, Irg 651, Irg 369, and Irg 184). The study evaluates optimum photoinitiator concentration and radiation dose. Various film properties such as gel content, swelling ratio in acetone, pendulum hardness, tensile strength, and elongation at break were determined. These formulated solutions were coated on wood substrates, and gloss and hardness of the film cured on the wood substrate were determined. Some of these properties are compared with those of the films cured on the glass plates. Irg 369 is found to be the best photoinitiator to produce better films, both on glass plate and on wood substrate. 相似文献
105.
Asl B.M. Mahloojifar A. 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2009,56(9):1923-1931
Currently, the nonadaptive delay-and-sum (DAS) beamformer is used in medical ultrasound imaging. However, due to its data-independent nature, DAS leads to images with limited resolution and contrast. In this paper, an adaptive minimum variance (MV)-based beamformer that combines the MV and coherence factor (CF) weighting is introduced and adapted to medical ultrasound imaging. MV-adaptive beamformers can improve the image quality in terms of resolution and sidelobes by suppressing off-axis signals, while keeping onaxis ones. In addition, CF weighting can improve contrast and sidelobes by emphasizing the in-phase signals and reducing the out-of-phase ones. Combining MV and CF weighting results in simultaneous improvement of imaging resolution and contrast, outperforming both DAS and MV beamformers. In addition, because of the power of CF in reducing the focusing errors, the proposed method presents satisfactory robustness against sound velocity inhomogeneities, outperforming the regularized MV beamformer. The excellent performance of the proposed beamforming approach is demonstrated by several simulated examples. 相似文献
106.
Azam Sobhani Masoud Salavati-Niasari 《Journal of Materials Science: Materials in Electronics》2016,27(4):3271-3280
In this article, the synthesis and characterization of Co2P/Co nanocomposites are reported. Three kinds of precursors are studied: bis(salicylidene)cobalt(II) [Co(sal)2], bis(salicylate)cobalt(II) [Co(Hsal)2] and cobalt oxalate [Co(O4C2)·4H2O]. The cobalt(II) acetate tetrahydrate Co(CH3COO)2·4H2O is used as reference. The nanocomposites are prepared by thermal decomposition method using triphenylphosphine as a surfactant solvent and phosphorus precursor. A possible mechanism of the formation of the nanocomposites is put forward to explain the experimental observations. This is the first time that Co2P/Co nanocomposites are synthesized. To study the crystalline structure, composition, size, morphology and magnetic property of the products, characterization techniques including XRD, SEM, TEM, FT-IR and VSM are employed. 相似文献
107.
108.
109.
Mehdi Shafiee Ardestani Alireza Salehi Fordoei Asghar Abdoli Reza Ahangari Cohan Golnaz Bahramali Seyed Mehdi Sadat Seyed Davar Siadat Hamid Moloudian Nasser Nassiri Koopaei Azam Bolhasani Pooneh Rahimi Soheila Hekmat Mehdi Davari Mohammad Reza Aghasadeghi 《Journal of materials science. Materials in medicine》2015,26(5):1-8
110.
Taher Rahimi Aghdam Habib Mehrizadeh Dariush Salari Hui-Hsin Tseng Aligholi Niaei Azam Amini 《Korean Journal of Chemical Engineering》2018,35(4):994-999
Perovskite type BiFeO3 (BFO) was synthesized by sol-gel auto-combustion method. Synthesized BFO was immobilized on the micro slides glass plates by sol-gel dip-coating method. The sample was characterized by XRD, FESEM, UV-Vis DRS, and BET techniques. The XRD pattern confirmed the perovskite structure, and from the Debye-Scherrer equation the average crystalline size was calculated as 19 nm. The FE-SEM images of prepared BFO showed porous structure with low agglomeration. The band gap energy was calculated about 2.13 eV, and the specific surface area (SSA) of prepared BFO nanostructure was obtained 55.1m2 g?1. The photocatalytic activity of prepared pure and immobilized BFO was investigated in the removal of NOx under UV irradiation, in the batch photoreactor. The effects of operational parameters such as initial concentration of NOx, light intensity and amount of coated photocatalyst, under identical conditions, were investigated. The results showed that the highest conversion of NOx was obtained as 35.83% in the 5 ppm of NOx with 1.2 g immobilized BFO and under 15 W illumination lamp. 相似文献