Twinning induced plasticity (TWIP) steels with high manganese percentage (17-35%), are mostly used in automotive bodies. Their microstructure at room temperature is austenitic, and due to the low stacking fault energy, major deformation mechanism in them is twinning inside austenite grains which leads to enhanced mechanical strength in the steel. Due to the important effect of heat treatment process on mechanical properties, FULL ANNEALING heat treatment and resultant twins were investigated in this study. To this aim, the steel was casted, hot rolled, and then heat treated at different times and temperatures and the obtained microstructures were analyzed using optical microscope. The results showed that the percentage of ANNEALING twins is increased with increasing ANNEALING temperature up to 1100oC, the peak point at which grain growth stage starts, and increasing temperature above that decreases twins’ percentage. A relation between grain size and ANNEALING twins’ percentage was found. FULL ANNEALING temperature for this steel was determined to be 1100oC.

Twinning Induced Plasticity (TWIP) steels, with high manganese percentage (17-35%), are used in automotive bodies. Their microstructure at room temperature is austenitic and due to low stacking fault energy, major deformation mechanism in them is twinning inside austenite grains which on the other hand, leads to enhanced mechanical strength in steel. Due to important effect of heat treatment process on mechanical properties, FULL ANNEALING heat treatment and effect of Molybdenum were investigated in this study. To this aim, the steel was casted and hot rolled and then heat treated at different temperatures and the obtained microstructures were analyzed using optical, SEM and TEM microscopes. The results showed that the FULL ANNEALING temperature for steel without Mo was determined to be 1100oC. and addition Mo to the steel ANNEALING Temperature by 50oC reduced.

The set covering problem (SCP) is one of the location -allocation models. It s objective is to minimize the cost of facilities location-allocation in an optimal structure in such a way that each customer or zone has been covered by at least one facility. The above problem is a class of NP-Hard problems that cannot be solved by exact algorithms in a reasonable amount of computational time. Thus in this paper, a simulated ANNEALING (SA) algorithm is proposed to solve the SCP. This algorithm is one of the efficient metaheuristics based on a neighbourhood search within solution space, acceptance of probability, and inferior solutions to scape from trap (i.e., local optimal solution). Ten test problems are solved in which associated results show the efficiency and validity: of the SA algorithm for solving the SCP. The validity comparisions of the results obtained the proposed algorithm are compared with the results reported by three methods named as Lingo 8 Software, Heragu's heuristic, and Genetic Algorithms (GAs).

In this study, IN738LC super alloy samples were solutionized at 1210 ° C for 5 hours. After solutionizing, the samples were cooled in both air and liquid nitrogen. One of the air-cooled samples after reaching the room temperature was stored in liquid nitrogen for 2 hours. To investigate the effects of high cooling rate and sub-zero operations on the microstructure and hardness, the samples were characterized by scanning electron microscopy (SEM) and hardness test. Deeper sub-zero operations reduced the size of the sediment to 117 nm. While cooling in liquid nitrogen reduced the size of the sediment to 76 nm. This suggests that the cold weather in the air has provided the opportunity for growth to precipitate. By increasing cooling rate and keep at deep zero, the hardness of the samples decreased, so that the minimum hardness was related to the sample stored in liquid nitrogen. The results of this research can be applied to new blades after casting and also under service and to help improve the heat treatment process.

In most service and production systems, there is a need of planning and scheduling the multi-shifts work. This paper presents a manpower scheduling problem in order to assign a work pattern (shift-day) considering system and workforce requirements. The objective is to minimize all cost incurred in the proposed mathematical model. This problem belongs to the class of NP-complete ones due to its time complexity function that it cannot be solved by traditional optimization methods in a reasonable computational time. For this reason, a number of heuristic methods have been proposed to solve such a hard problem. In this paper, a heuristic-based simulated ANNEALING is designed and applied. A number of test problems are generated at random and the associated solutions are compared with the Lingo 6 software in order to evaluate and show efficiency of the proposed algorithm.      

Using FULL duplex communication systems called FD, is a new technique for increasing the spectral efficiency. That`s why it has been considered seriously in the new generation of communication systems. The main challenge of the FULL-duplex system is the self-interference, which has to be decreased properly. In this paper, we consider a FULL-duplex cellular network base station and using the antenna selection technique to reduce its self-interference issue. For appropriate antenna selection, we present a new criterion. In this new criterion, antenna selection has been modeled and solved as a multi-objective optimization problem. In this new criterion, antennas which simultaneously minimizes interference channel gain and maximizes uplink (UL) and downlink (DL) channel gains are selected for transmission and reception. Since the goal of the base station is a good performance in both the UL and DL channels and reduction of the self-interference simultaneously, the multi-objective criterion has a better performance when compared to single-objective criteria. In the common single-objective criteria, only the UL and DL channels or interference channel is considered. Finally, simulation results show that the new criterion has more throughput rate than the other single-objective antenna selection technique in the FULL duplex systems.