In this paper, the economic production is considered by considering defective products during production, a percentage of which can be recycled at a fixed cost, also machine failure, and variable demand. It is assumed that the products are produced at a fixed rate, but the machine may break down during production. Machine failure during production is a random variable that follows an exponential distribution with a specified parameter. If the machine breaks down during production, production stops immediately and the machine is repaired, and this study assumes that the machine repair time is a fixed value. Also, unlike the classical models, the demand for the manufactured product is expressed as a non-incremental function of time. The main goal is to determine the optimal policies for reproducing the problem in such a way that the total annual cost is minimized. For this purpose, first, a mathematical model is presented, then, the average cost per unit of time is determined, and based on the concepts of global optimization, the optimal values are determined. Finally, by solving a numerical example, the problem is analyzed. The results show that, the repair time has a great impact on the cost of the entire system, and as it increases, the system cost increases exponentially.

Nowadays, due to the high expectations of customers in meeting their demand and the competition environment among service providers, employers are working to provide customers with new methods in the shortest possible time and in the best possible way to attract customer’ s satisfaction and maximize profits. In this paper, the orienteering problem with variable profits, fractional objective function and demand on arcs is studied. An appropriate integer programming model is proposed to solve it. In this case, the purpose is to determine a route for a vehicle so that it maximizes the profit, the start and end of its route is at the origin, serving demands of customers, and does not exceed a maximum allowed travel time. In the orinteering problem with variable profits and fractional objective function the customers are located on vertices of the graph corresponding to the problem. Next, a problem is considered in which the service is performed on arcs. The resulting problem is called the orinteering arc routing problem with variable profits and fractional objective function. We solve the problem by bisection method. In the end, the numerical efficiency of the proposed model is examined. The proposed algorithms can solve problems in a reasonable amount of time. We will also see that the time of solving problems depends on their graph structure and not on their size.

Crisis Management includes planning and readiness to respond to the inevitable and unpredictable natural disasters. One of the aspects of crisis planning and management is the establishment of relief centers in suitable locations for responding promptly to potential victims after the disasters. In this paper, the problem locating relief centers in relief logistics is investigated in the framework of the problem of locating with the variable coverage radius model. It is assumed that the time to reach all points of the demands is not greater than a predetermined value. Since the population in need of relief (demand) is a function of the severity of the disaster and certainly is not determined before the occurrence, the proposed model is considered uncertain. In this paper, a robust two-objective mathematical planning model (minimizing logistics costs and maximizing the covered population) is developed with uncertain demand to determine the number, location, coverage, and capacity of different relief centers with different service levels. To evaluate the validity of the proposed model, one of the districts of Tehran was studied as a case study to determine the number and location of the relief centers, along with their capacity and type of service. The results in the case study show we need to construct five relief centers with appropriate distribution in the region which capable of to cover 90 percent of all potential demand points.

In most irrigation systems in our country, the pumping stations are equipped with fixed speed pumps. These pumps in addition to causing water waste, demand extra energy. Providing a method for adjusting the pumps to function according to obligations of operation can improve efficiency of water distribution as well as energy efficiency. One of the choices toward this aim, is to employ the variable speed pumps which adjust with the variable demand of system. In this study, by coding in MATLAB software, design of pumping stations equipped with variable- speed pumps was done for a drip irrigation system. Then with regard to variable demand of discharge and pressure during irrigation season, the designed system was evaluated and compared with some ordinary operation methods based on constant speed pumps. The results show that the performance of variable- speed pumps to supply the pressure head and discharge is largely definitely acceptable; while water losses in ordinary pumping stations, depending on the type of station, amount to from 16 to 36 percent.

This paper proposes a mathematical model to solve facility layout problem in CMS. Its objective is to solve both inter-cell and intra-cell facility layout problems simultaneously, so that the material handling costs are minimized. It has been assumed that the demand rate varies over the product life cycle. Due to the complexity of the case, an improved simulated annealing algorithm has been developed to provide the optimal solution to this problem. This algorithm can always generate a neighborhood configuration that satisfies all of the zoning constraints. The results indicated that the proposed approach can yield satisfactory solutions within reasonable time.  

Background: Common variable immune deficiency (CVID) is the commonest symptomatic primary immunodeficiency and represents a heterogenous collection of disorders resulting mostly in antibody deficiency and recurrent infections. The syndrome includes impaired B-cell maturation, impaired somatic hyper mutation, reduced numbers of circulating memory and isotype-switched memory B cells, and absent or reduced plasma cells. B cell maturation antigen (BCMA) is a tumor necrosis family receptor superfamily member 17 (TNFRSF17), expressed only on B cell lines, and is essential for survival of long-lived plasma cells. The aim of this study was to evaluate mutations in BCMA in patients with CVID in compare with normal individuals in Isfahan, Iran.Methods: Blood samples were collected from 10 CVID patients with substitutive immunoglobulin therapy before immunoglobulins (Ig) infusion and 10 normal controls in ethylenediaminetetraacetic acid (EDTA) tubes then DNA samples were extracted and after the polymerase chain reaction (PCR) was done, samples were sequenced.Findings: After reviewing the results of the sequence and alignment of the sequences, no mutations in the gene were seen.Conclusion: In addition to the study of mutation in BCMA gene, BCMA gene and protein expression level should be considered to understand more aspects of this disease.

The Effect of different culture conditions on growth and production of antimicrobial agents by Oudemansiella spp, using the Variable Size - Simplex Design, were investigated. The results obtained from the experiments indicated that the optimum condition for growth and production of antimicrobial agents, situated at pH between 5.6 and 6.8, temperature between 28°C and 30.6 ºC, shaking rate between 137 and 170 rpm. The results also showed the fungus grow and produced antimicrobial agents at a very wide range of glucose concentration. Increasing the concentration of glucose over 15 g/L, resulted in decreasing the activity of the fungus.