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Noe Oliva-Moreno L.,Escuela Superior de Computo Del IPN
Advanced Materials Research | Year: 2014

In this paper a low voltage FGMOS analog multiplier is proposed that uses a follower voltage flipped (FVF), which dominates its operation. In order to reduce the power supply of the multiplier, floating gate CMOS transistors (FGMOS) are used. Theoretical steps of the FVF design are presented together with its simulation. The output of the FVF is insensitive to the device parameters and is loaded with a resistive load. The multiplier design consists of two FVF cells, two current sensors FVF and one Gilbert cell multiplier. The results show that the proposed multiplied in a 0.13μm CMOS process exhibits significant benefits in terms of linearity, insensibility to device parameters, bandwidth and output impedance. The power supply is 0.8V and a power consumption of 181μW. © (2014) Trans Tech Publications, Switzerland. Source


Barranco-Jimenez M.A.,Escuela Superior de Computo Del IPN | Paez-Hern'andez R.T.,Metropolitan Autonomous University
Entropy | Year: 2011

In this work we present a local stability analysis of the thermo-economic model of an irreversible heat engine working at maximum power conditions. The thermo-economic model is based on the maximization of a benefit function which is defined by the ratio of the power output and the total cost involved in the plant's performance. Our study shows that, after a small perturbation, the system decays exponentially to the steady state determined by two different relaxation times. In particular, we show that the relaxation times are function of the temperature ratio T = T 2/T 1 (T 1 > T 2), the cost function f and the parameter R (a parameter related to the degree of internal irreversibilities). We observe that the stability of the system improves as T increases whereas for changes in f and R, the stability properties are characterized by a rapid decay along the fast eigendirection as f increases and R decreases. Finally, we discuss our results in the context of energetic properties. © 2011 by the authors. Source


Barranco-Jimenez M.A.,Escuela Superior de Computo Del IPN | Sanchez-Salas N.,Escuela Superior de Fisica y Matematicas del IPN | Angulo-Brown F.,Escuela Superior de Fisica y Matematicas del IPN
Entropy | Year: 2011

In the present paper, the thermoeconomic optimization of an irreversible solar-driven heat engine model has been carried out by using finite-time/finite-size thermodynamic theory. In our study we take into account losses due to heat transfer across finite time temperature differences, heat leakage between thermal reservoirs and internal irreversibilities in terms of a parameter which comes from the Clausius inequality. In the considered heat engine model, the heat transfer from the hot reservoir to the working fluid is assumed to be Dulong-Petit type and the heat transfer to the cold reservoir is assumed of the Newtonian type. In this work, the optimum performance and two design parameters have been investigated under two objective functions: the power output per unit total cost and the ecological function per unit total cost. The effects of the technical and economical parameters on the thermoeconomic performance have been also discussed under the aforementioned two criteria of performance. © 2011 by the authors. Source


Ahmadi M.H.,K. N. Toosi University of Technology | Ahmadi M.H.,Institute Of Recherche En Genie Chimique Et Petrolier Irgcp | Mohammadi A.H.,Institute Of Recherche En Genie Chimique Et Petrolier Irgcp | Mohammadi A.H.,University of KwaZulu - Natal | And 2 more authors.
Energy Conversion and Management | Year: 2013

A solar-powered high temperature differential Stirling engine has been considered for optimization with multiple criteria. A mathematical model based on the finite-time thermodynamics has been developed so that the output power and thermal efficiency and the rate of entropy generation of the solar Stirling system with finite rate of heat transfer, regenerative heat loss, conductive thermal bridging loss and finite regeneration process time are obtained. Furthermore, imperfect performance of the dish collector and convective/radiative heat transfer mechanisms at the hot end as well as the convective heat transfer at the heat sink of the engine are considered in the developed model. Three objective functions including the output power and overall thermal efficiency have been considered simultaneously for maximization and the rate of entropy generation of the Stirling engine are minimized at the same time. Multi-objective evolutionary algorithms (MOEAs) based on NSGA-II algorithm has been employed while the Effectiveness's of regenerator, the Effectiveness's of the low temperature heat exchanger, the Effectiveness's of the high temperature heat exchanger, heat capacitance rate of the heat sink, heat capacitance rate of the heat source, temperatures of the working fluid in the high temperature isothermal process and temperatures of the working fluid in the low temperature isothermal process are considered as decision variables. Pareto optimal frontier has been obtained and a final optimal solution has been selected using various decision-making approaches including the fuzzy Bellman-Zadeh, LINMAP and TOPSIS methods. © 2013 Elsevier Ltd. All rights reserved. Source


Ahmadi M.H.,K. N. Toosi University of Technology | Dehghani S.,K. N. Toosi University of Technology | Mohammadi A.H.,Institute Of Recherche En Genie Chimique Et Petrolier Irgcp | Mohammadi A.H.,University of KwaZulu - Natal | And 2 more authors.
Energy Conversion and Management | Year: 2013

To study the optimum design factors and the optimal thermo-economical performances an optimal performance analysis of a solar driven heat engine system at maximum thermo-economical objective function conditions is done numerically. In the present investigation, thermodynamic analysis and NSGAII algorithm are employed to optimize objective function associated to the power output, thermal efficiency for a Solar driven engine system. Three decision-making procedures are applied to optimized answers from the results. The error through investigation is shown using error analysis. © 2013 Elsevier Ltd. All rights reserved. Source

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