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In macroeconomics literature inspired by traditional economists, it is said that economic growth and more equal distribution in income, are two opposite targets since moving toward more equality of income, will reduce propensity to saving. Based on the optimum growths models, it seems that the highest levels of growth can happen in a system just when in allocating the resources among the generations the attention is more paid to the concept of justice. If in this process the attention is more paid to the present generation compared to the future ones, the available resources for the whole system will decrease and as a result the economic growth will be stabilized at far lower rates. The more economic justice means the higher rate for economic growth. In this paper we use an optimal growth theory for studying the mechanics of this regularity. Empirical calibration of the model to the Iranian economy reveals that if economic policy makers in a planning period via a scenario can decrease social time preference to a 5%, real per capita GDP, consumption, saving and per capita capital formation will increase by 6.5%, 2.2% and 42% respectively.

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Using Ramsey – Cass – Koopmans optimal growth model and specifying government’ tax behavior, this study analyzes the effect of tax policies on steady-state and optimal dynamic path of consumption, capital stock and  output for Iran and a group of East Asian countries. In this regard, after specifying consumption and capital stock dynamic behaviors, a model is calibrated and simulated for the selected economies by using annul data during 1980 -2010. Based on the simulation results for Iran, and compared to East Asian region, reductions in tax rates have no significant effects on steady- state and optimal dynamic path of capital stock, consumption and per capita output. Hence, tax policies are not effective in stimulating the real sector of the Iranian economy. The results also show that reductions in rates of income tax, capital gain tax and profit tax have positive and significant effects on the long-run steady-state path of consumption, capital stock and output, especially in less developed East Asian countries. The simulation results show that reduction in consumption tax rate, in particular across the highly developed East Asian countries, has positive and significant effect on steady-state of consumption; however, it has no effect on capital stock and output.   

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Gas turbines are among the most important power generation equipment in industries. One of the methods to enhance the performance of this equipment is the aerodynamic performance optimization of its stator and rotor blades. This paper presents an automatic aerothermodynamic optimization platform for the optimization of 3D stator blade geometry in axial-flow gas turbines using open-source software. This platform can be used for 3D aerothermodynamics optimization of 3D blades and includes parametric 3D modeling, mesh generation, CFD simulation, and implementation of optimization algorithm. 3D models are formed from 2D sections defined by Bézier curves and connected by spline stacking curve. Simulation of flow field includes the solution of compressible viscous flow on structured multi-block grid using parallel processing. Genetic algorithm is used as optimization algorithm. 45 optimization variables govern blade thickness variation in five sections and blade lean, sweep, and twist. Total pressure is selected as objective function and the result of optimization shows 5% decrease of total pressure loss coefficient in the blade. The use of open-source software in the optimization platform provides maximum customization capability to the user. The application of this platform for stator blade optimization shows that the platform can be used for aerothermodynamic optimization of turbomachines effectively.