فهرست مطالب abdolrasool ghasemi

In today's electronic and digital world, increasing demand for portable systems has led the electronics industry and chip design technology to reduce power consumption methods, and therefore power consumption has become an important criterion in this field. Also, increasing the speed of chips and reducing the propagation delay of circuits has always been an important goal of digital design engineers. Since the Adder element is one of the important elements in many digital systems, so today various Adders with different technologies and design approaches have been proposed, each of which has certain advantages and disadvantages. This paper presents a low-power single-bit full-adder cell design that is based on pass-transistor logic.This circuit is used in the arithmetic logic units of digital signal processors and also in several electronic and digital communication systems that operate within the frequency range of in 1GHz. The proposed cell exploits the pass transistor techniques and XOR-XOR structures to improve the design parameters namely power consumption, propagation delay, power–delay product, and the number of transistors. The proposed circuit is designed using 180nm CMOS technology and the simulation results show that for a supply voltage of 1.8V, the power consumption, delay, and power–delay product have been achieved as 83 W, 89ps, and 7fJ respectively.

The electricity supply security has played a vital role in the economic development of Iran. However, a large number of electricity supply disruptions has happened in recent years, which lead to electricity shortage costs in the level of economic sectors. Using a combination of Input-Output analysis and the Linear Programming method, this study measures the producer price index as average costs of Iranian economic sectors after imposing a unique scenario of a 30% potential electricity shortage supply. In this regard, we employ an Iranian symmetric Input-Output 14Í14 industry-by-industry Table for the year 2011. The results of this study indicate that the most shortage cost occurs for the manufacture of wood and paper products, while the services have the lowest cost after electricity supply disruption. Besides, increasing the costs of non-electricity sectors in the Iranian economy after the electricity supply shock is 175.63% on average. The quantitative results are useful for policymakers attempting to set strategic plans to reduce the electricity cost in manufacturing sectors and optimal distribution of limited electricity resources to reduce the overall cost of blackouts.

In this paper, a robust dynamic slip mode controller for an electrical robot manipulator is presented. The control law calculates the motor voltage based on the voltage control strategy. Uncertainties are estimated using the Fourier series expansion and the cutting error is compensated. Fourier coefficients are adjusted based on stability analysis. Also in this paper is the design of a robust controller using a new adaptive Fourier series extension. Compared to previous related works based on the Fourier series expansion, the advantage of this paper is that it provides a matching law for the main frequency of the Fourier series expansion and thus eliminates the need for trial and error in its regulation. A case study of a Scara robot powered by DC magnet electric motors. The effect of uncertainty estimation based on the Fourier series expansion is studied instead of using the sign function. The proposed method is also compared with Legendre polynomials. The simulation results confirm the robust and satisfactory performance of the proposed controller.

Analog to digital converters are divided into two categories, Nyquist rate converter and oversampling converter, in terms of sampling frequency. At oversampling converter, input signal are sampled at several times the Nyquist rate. Increasing the over sampling rate leads to an increase in effective resolution, but although the use of high sampling rate for wide band signals is impractical due to the need for high sampling frequency and power consumption. Increasing the number of bits also increases the dynamic range as opposed to the multi-bit DAC required in the linear feedback path. In this paper, we designed sigma delta structure with 12 bit resolution, 1-v power supply for low power applications. on the other hand, increasing levels of quantization(number of bits) causes the reduction in-band noise power of the system, as well as the modulator stability improves without need increasing oversampling ratio. The maximum value of a signal-to-noise-and-distortion ratio(SNDR) will be achieved by means of choosing appropriate feedback coefficients. Simulation results of a 12-bit,2.4-MS/s , and 1-v proposed structure in a 0.18-µm CMOS technology show a signal-to-noise-and-distortion ratio (SNDR) of 71.3 dB, a power consumption of 451µW, and figure of merit 3.76(pJ/Conver.step.)

The rapid development of gas distribution in Iran causes considerable dependence of consuming sectors on Natural Gas production .The share of South Pars Gas Field from the entire gas production in the end of sixth Five-Year Iranian Economic Plan will be over 62%. The pressure of reservoir gradually reduces and subsequently the volume of gas production declines in the production period due to the natural technical condition of South Pars reservoir. Installation of gas compressor platform is necessary in order to delay the reduction of the production. In spite of installation of these platforms,unofficial announcements indicate that production from South Pars field will decrease significantly in the twenty–year prospect and supply of new gas fields cannot compensate this reduction. Hence, in order to prevent gas shortage crisis in the coming years, it is required to predict some strategic actions and prioritize the supply of gas for new demand sectors. The "AHP" model has been applied to determine the priorities for this purpose. The relevant calculations have been carried out for solving the model by selecting a total of 8 options and 6 criteria by using the Expert Choice Software. The priorities of this study for each option are as follows respectively: Injection into Oil Reservoirs, Gas supply to Power Plants, Export, Feedstock for Petrochemical Units, Gas supply to Industries, Gas supply to Residential& Commercial , Transportation

This paper examines the causality between concentration in banking industry and economic growth by using data across 15 countries named in «Iran outlook in 2025», over the period 2004-2011. Our aim is to assess whether the economy grows more or less rapidly in areas where the banking sector is more concentrated. The topic is motivated by the fact that the causality between concentration in banking industry and economic growth has not been examined in Iran and the countries named in Iran Outlook 2025. In order to investigate the relationship, the standard Granger causality test and Hsiao’s version of Granger causality test are employed in this paper. The results show that banking concentration is negatively associated with economic growth. Besides, the evidence suggests that economic growth has a positive effect on bank monopoly power.

The impact of information & communication technology (ICT) on people''s lives can be study in different aspects. From economic and environmental perspective، the outcomes of the efficiency and productivity activities، has an important role because the improvement of efficiency provides a basis for reducing energy consumption. This Paper examines the impact of information & communication technology (ICT) on petroleum products in transportation Sector of the selected OECD & OPEC countries for the period 2000-2010، and for this purpose، dynamic panel modes are used. The results show that ICT has different rules in the samples. In the selected OECD countries، more use of information and communication technology can increase the intensity of consumption of petroleum products of the transportation sector، while in the selected OPEC countries more use of ICT can reduce the intensity of consumption of petroleum products of the transportation sector and ICT has the potential for reduction of energy intensity in the transportation sector of these countries that have high energy intensity.

The major function of a financial market in the literature on economy represents a way to conduct and dedicate capital. Banks in developing countries have a main role in this way; we can find some variables effective on market structure to advocate capital more efficiently. This paper studies the importance and impact of macroeconomic variables on banking system structure within 15 out of 20 years of Iran's perspective plan. The study has used a fixed-effect panel data method during 2002 to 2009. The results show that the logarithmic form of per capita GDP is the most important variable in market power description as a proxy for institution development. Other institutional variables such as economic freedom index, governance index and financial freedom index have the second importance after the bank special variables (loans to asset ratio and total asset logarithmic form). Inflation rate has a little significant effect on the structure of banking industry, and GDP growth rate has no significant effect on it.