توجه: محتویات این صفحه به صورت خودکار پردازش شده و مقاله‌های نویسندگانی با تشابه اسمی، همگی در بخش یکسان نمایش داده می‌شوند.
۱Application of Nonlinear Filtering for Sea Clutter Prediction
نویسنده(ها): ، ،
اطلاعات انتشار: دوازدهیمن کنفرانس مهندسی برق ایران، سال
تعداد صفحات: ۶
Application of nonlinear predictor for sea clutter was restricted to sea clutter chaotic model .This paper is concerned with the application of a nonlinear predictor for sea clutter modeled statistically, using a zero–memory nonlinearity (ZMNL) followed by a second order Volterra filter(SVF) as described in [2] . First partial statistical information such as marginal probability density function (PDF)and the covariance structure are exploited .The clutter PDF parameters are estimated by a combinational method based on maximum likelihood and method of moments ,resulting in the lowest variance of parameter estimation as mentioned in [5]. The ZMNL transformes the process
into a Gaussian process, finally the transformed process is predicted by a SVF. The improvement concerned with application of the nonlinear predictor, when compared with linear one is outlined.<\div>

۲Evaluation of the Shear Wave Velocity Using GMDH–Type Neural Network
نویسنده(ها): ،
اطلاعات انتشار: چهارمین همایش بین المللی مهندسی ژئوتکنیک و مکانیک خاک ایران، سال
تعداد صفحات: ۶
The use of the shear wave velocity is increasing to predict some geotechnical. In many cases the field geophysical and geotechnical investigations are implemented to measure in–situ shear wave velocity. Because these methods are not easy and economic to carry out in all cases, the empirical methods are more interesting. Shear wave velocity is influenced by many factors such as void ratio, state of stress, stress history, and many other soil parameters, and it is difficult if not impossible to simultaneously consider in an empirical model. The interactions between these factors and shear wave velocity are complex. Therefore, it is worthwhile to find a predictive model to correlate the shear wave velocity with main influenced parameters. In present study, a new model has been developed to predict the shear wave velocity using a group method of data handling (GMDH) type neural network. The proposed model shows an appreciable achievement in prediction of shear wave velocity.<\div>

۳Electrochemical study of polyaniline\Ag and poly (o–Metylaniline)\Ag nanocomposites as conducting polymer in fuel cells
نویسنده(ها): ، ،
اطلاعات انتشار: چهارمین همایش پیل سوختی ایران، سال
تعداد صفحات: ۹
This paper shows an exhaustive presentation and complementary discussions on various aspects of works done recently on the developments of composite membranes for polymer electrolyte fuel cell (PEFC) applications. The electropolymerisation of Polyaniline\Ag (PANI\Ag) and poly(o_methylaniline)\Ag (PoMeANI)\Ag nanocomposites were prepared by insitu oxidative polymerization of aniline monomer in the presence of different concentrations of Ag nanoparticles. The formation of PANI\Ag and its derivative nanocomposites was characterized by FTIR and UV–vis spectroscopy. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to investigate the electrochemical properties Polyaniline\Ag and poly(o_metylaniline)\Ag .CV and EIS results show that the PANI\Ag film exhibits considerably higher electroactivity compared with its derivative. The research interest is to implement the conducting polymers in fuel cell technology, as Membrane Electrolyte fuel cell components or conducting supports for noble metal deposition.<\div>

۴Determination of Imipramine by Selective Solid Phase Extraction Using Molecularly Imprinted Polymers (MIP) and Liquid Chromatography
نویسنده(ها):
اطلاعات انتشار: دومین کنفرانس بین المللی یافته های نوین پژوهشی در شیمی و مهندسی شیمی، سال
تعداد صفحات: ۱۱
The Molecularly Imprinted Polymers (MIP) are polymers possessing specific cavities designed for a target molecule. MIP are synthetic polymers having a predetermined selectivity for a given analyte, or group of structurally related compounds that make them ideal materials to be used in separation processes. In this study new absorbent for molecularly imprinted solid phase extraction of Imipramine from aqueous solution was synthesized using Methacrylic acid (MAA) as functional monomer, Ethylene glycol dimethacrylate (EGDMA) as a cross linker, 2–2'–Azoisobutyronitrile (AIBN) as initiator and chloroform as porogen, causing a non–covalent bulk polymerization. The synthesized MIP and NIP were characterized by FT–IR spectroscopy, UV–VIS spectrophotometer, thermo gravimetric analysis (TGA\DTG) and scanning electron microscope (SEM). The factors that probably influence the solid phase extraction process, such as pH of loading sample, eluent solvent, loading and eluent solvent flow–rate, volume of the loading and eluent solvent and sorbent mass, were investigated. The recovery percent, limit of detection (LOD), limit of quantification (LOQ) and relative standard deviation (RSD %) for human plasma samples by introduced selective solid phase extraction were 94%, 10 ngmL–1, 33 ngmL–1 and 2.8% respectively. Furthermore, the imprinted polymers were successfully applied as a specific solid–phase extractants combined with high performance liquid chromatography (HPLC) for determination of imipramine in the human plasma samples.<\div>

۵Implementation of flotation and gravity separation, to process Changarzeh sulfide–oxide lead ore
اطلاعات انتشار: Journal of Mining and Environement، سوم،شماره۲، ۲۰۱۲، سال
تعداد صفحات: ۱۰
This study aimed to explore concentration of a low grade sulfide–oxide lead–zinc sample containing 2.3% Pb, 1.91% Zn taken from Changarzeh mine, South Natanz, Iran. The effects of different parameters such as type and dosage of collector, milling retention time, dosage of sodium sulfur and its preparation time, application of sodium silicate, pH and solid content were investigated in relation to flotation efficiencies. Optimum experiment was carried out in cumulative flotation with 200g\t KAX as collector, 2000g\t Na2S, 500g\t sodium silicate, 30g\t MIBC and at pH=10. This test yielded 94% of lead recovery under optimum condition performance, and a concentrate with 70%Pb was produced through cleaning stages. Eighteen minutes was found to be the optimum time for lead flotation in laboratory scale. Application of gravity method for the production of a middle product was also considered. For shaking table the effect of table slope and water flowrate and for jig the effect of water flowrate and frequency were studied. Gravity separation by shaking table resulted in a concentrate with 46%Pb and 80% recovery, so shaking table could be proposed for production of pre–concentrate.
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