توجه: محتویات این صفحه به صورت خودکار پردازش شده و مقاله‌های نویسندگانی با تشابه اسمی، همگی در بخش یکسان نمایش داده می‌شوند.
۱Performance Analysis of AFSMC Control of AFM Microcantilever with Chaotic Motions
نویسنده(ها): ،
اطلاعات انتشار: سومین کنفرانس نانوساختارها، سال
تعداد صفحات: ۴
In this paper, the nonlinear dynamics and chaotic behaviour of AFM tip–sample dynamic system, being run in the non–contact mode (TM), were investigated by considering the effects of hydrodynamic loading and squeeze film damping. The microcantilever was modelled as a spring–mass–damping system and the interaction between the tip and the sample was described by the Lennard–Jones (LJ) potential .then a robust adaptive fuzzy control algorithm for control of this chaotic system have been used. The control approach encompasses a fuzzy system and a robust controller. The fuzzy system is designed to mimic an ideal controller, based on sliding–mode control. The robust controller is designed to compensate for the difference between the fuzzy controller and the ideal controller. The parameters of the fuzzy system, as well as uncertainty bound of the robust controller, are tuned adaptively. The results showes that either the controller has a remarkable success in controlling the chaotic behaviour of AFM microcantilever, the control system can detect the variations of the surface of the sample which perform as a external disturbance and show it in input control signal<\div>

۲3D COBALT COORDINATION POLYMER:SYNTHESIS, AND CO2 ADSORPTION
نویسنده(ها): ، ،
اطلاعات انتشار: اولین همایش ملی تکنولوژی های نوین در شیمی و پتروشیمی، سال
تعداد صفحات: ۶
The crystal structure and vibrational spectra of {(CH6N)[Co(CHO2)3]}n, the structure consists of a threedimensional net of central Co (II) ions connected via formate (methanediolate) bridges. The negative charge iscompensated by protonated methylamine cations. One of the Co (II) ions adopts a disordered octahedral geometry, coordinated by six O atoms from three different formate ligands. IR vibrational spectra were recorded and the full assignment of the vibrational frequencies is proposed. CO2 adsorption performances of the crystals were investigated at ambient temperature and pressure (1 atm), and diagram shows the corresponding CO2 adsorption–desorption isotherms of the crystals.<\div>

۳Cold Metal Forming of Columns with the Rectangular Cross–section Using the Circular Tubes
اطلاعات انتشار: کنفرانس دو سالانه بین المللی مکانیک جامدات تجربی، سال
تعداد صفحات: ۱۱
This article investigates a new method of cold metal forming of columns with rectangular cross–section using the circular tubes under the lateral loading by a U–shaped rigid die in two conditions: empty and polyurethane foam–filled by the experimental methods. During the experiments, the circular metal tubes are compressed between a rigid cubic punch and a U–shaped rigid die in the quasi–static condition to form the tubes into the rectangular columns. Some geometrical groups of the circular specimens were prepared and tested in empty and foam–filled conditions. The specimens were arranged in three different diameters, two different wall thicknesses and four different lengths. Also, for each geometrical characteristic, two other specimens were prepared and filled by the foam with two different densities. Effects of foam–filler, foam density, tube wall thickness, tube length and diameter are investigated on the cold forming process of rectangular columns. The experiments show that in most of the empty samples, an undesirable extra plastic hinge line is created during the forming process, but, this phenomenon is not observed in the filled specimens. Therefore, the experiments illustrate that filling the tubes by the polyurethane foam improves the deformation mode and final shape of the product comparing with the desirable form. Also, it is found that the final shape of the rectangular columns improves by decreasing initial tube diameter and wall thickness, but it is independent of tube length. The tests show that the required mean load of the process increases by increasing the wall thickness, tube length and foam density, and by decreasing the tube diameter.<\div>

۴Performance analysis of IIR ECG signal denoising filters during Iranian music
نویسنده(ها): ، ،
اطلاعات انتشار: ششمین کنفرانس مهندسی برق و الکترونیک ایران، سال
تعداد صفحات: ۵
high quality Electrocardiogram (ECG) recording can be used for properly interpretation and identification of heart activity. Since ECG is always corrupted by various kinds of noises such as Baseline wander, a filtering process will be necessary in order to extract useful information from the noisy ECG signals. This paper presents a detailed analysis of noise reduction approaches based on a case of linear infinite impulse response (IIR) filters. The performances of the filters are investigated considering the values of signal–to–noise ratio (SNR) and root–mean–square–error (RMSE). An analysis of variance (ANOVA) was also conducted to assess if there were any significant differences in SNR and RMSE values of the filtered signals. The results indicated that the mean scores for SNR and RMSE with Chebbyshev type I filter were significantly better. Ten linear time domain features, Standard Deviation (std), mean value, median, variance, second moment, third moment, minimum, maximum, signal energy and signal power were extracted for each original and filtered signal both in pre–music and during–music stages. Statistical comparison of mean values over pre–music and during–music stages, lead to different results for original and filtered signals which is due to the elimination of some useful information of ECG while filtering.<\div>

۵Optimization of Energy Consumption in an Electro–Pump Using a Novel Intelligent Drive Controller
نویسنده(ها): ، ، ،
اطلاعات انتشار: اولین کنفرانس بین المللی دستاوردهای نوین پژوهشی در مهندسی برق و کامپیوتر، سال
تعداد صفحات: ۸
This paper addresses an intelligent control technique to operate an electro–pump in an optimal speed such that the energy consumption becomes minimized.The proposed controller by using the tank's level signal and the pump's efficiency curves data and use of affinity laws and the gradient descending algorithm determine the optimum reference speed in order to reduce energy consumptions. This speed is used as a reference speed of the ACS800–ABB drive and the drive controls the motor using DTC method to reach to this optimal speed. The communication between proposed controller and drive is based on standards Profibus–DP. This controller is realized on FPGA. In order to show the effectiveness of proposed method Matlab\Simulink simulation provided and the results are reported.<\div>
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