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According to the neoclassical approach, input prices as a measure of resources scarcity induce firms to cost-minimizing and efficient allocation of recourses. But when the prices are distorted, the effective competitive inputs are used inefficiently and have resulted in under- or over-utilization of production factors relative to their endowments or allocative inefficiency. In this paper, the shadow cost approach and system of equations are used to estimate allocative inefficiency using the Iran's manufacturing data over the period 1976-2006. The results show that there is strong allocative inefficiency and increasing cost of production of firms in Iran's Manufacturing Sector.

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On one hand, the skill-based technologies increase productivity and output, reduce inflation and raise income. On the other hand, human skills are essential for implementing, adopting, utilizing physically and practically of modern and imported technologies and serve a complementary role in this respect. In the present paper, an attempt has been made to evaluate the relationship between the domestic research and development capital stock and technology imports with skilled and unskilled workers in Iran from 1971 to 2006. To do this, a translog cost function was estimated with seemingly unrelated regression method. The results indicate that the technology and its spillover are complementary to the skilled labor and substitute for the unskilled worker. In addition, the results illustrate the existence of a complementary relationship between capital and skilled labor and a substitution one with capital and unskilled worker.

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Islamic banking includes profit and loss sharing (PLS) and transaction contracts. Transaction contracts have fixed rates of return, which in turn form a base for allocating the financial resources to PLS contracts. In Iran, the rates of return in transaction contracts are determined by Central Bank. In this research, we compute and estimate the rates of return in transaction contracts using the Multi-Layer Perceptron (MLP) Artificial Neural Networks and Radial Basis Function (RBF). This research is an extension and improvement of Dadgar and Firoozan (2012) work. Data used for algorithms is the real data gathered from manufacturing workplaces having more than 10 employees. Our results show that two networks are of good accuracy to estimate the coefficients of shadow cost function, and most of them are approximately equal in two networks.
Compared to econometric method, the proposed model has no sampling limitation. This method accounts for all of 14000 manufacturing units in 2007, and consequently the computational errors are much less than those of econometric calculations. According to the results, the estimated rate of return for transaction contracts is 15%. This rate in comparison with the prevailing rate, i.e. 12%, reflects a 20% deviation in determining rate of return, which causes undeniable costs on the economy and allocation of limited resources.
 

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Comparison of Back stepping method optimized via particle swarm optimization algorithm and LQR method for hovering control of a quadrotor is presented in this paper. Quadrotor is not a stable dynamical system and development of high performance controllers for it is important. First the dynamic model of a quadrotor is introduced and state-space equations are presented in order to simulate the dynamic model. Then two Back stepping and LQR controllers are designed to control Euler angles and height of the quadrotor. In order to optimize back stepping controller, its parameters are determined using particle swarm optimization algorithm to minimize cost function considered for LQR controller. Also commands to the motors are calculated and plotted to show the feasibility of the controller. To obtain better comparison, the cost function is calculated for different weighting matrices of Q and R for two controllers and the results are compared. The results show that Back stepping controller has more ability to minimize the cost function in comparison to LQR and the cost function in Back stepping has less values for several choices of weighting matrices.

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Agriculture is one of the responsible sectors for adequate food production and contribution to food security. However, due to the rapid population growth and increasing demand for food, this responsibility is becoming more and more challenging. The consequence of this challenge is the excessive exploitation of natural resources and destruction of the environment. This study aimed to investigate the cost structure, economies of scale, and inputs elasticities for the major farm crops of the Qorveh-Dehgolan Plain, in Kurdistan Province, through a translog cost function. The needed data were collected through a multi-stage cluster sampling survey in the 2017-2018 cropping year. The results showed that the average share of water input in the total production cost of the studied products was 12%. Results also showed that all ordinary own-price elasticities of demand for inputs were negative and smaller than one. However, the results of Allen-Uzawa's own price elasticities showed that demands for inputs could be elastic. Ordinary and Allen-Uzawa own price elasticity of water input were -0.76 and -6.7, respectively. The results also showed that wheat, tomato, barley, and alfalfa farms in the area under study were facing economies of scale, on average, while potato, cucumbers, and sugar-beet farms were facing diseconomies of scale.