Original Research Paper
TVET
S. Ahmadi; A. Shokouh Far; M.R. Abutalebi; A. Rezaee
Abstract
Aluminum-lithium alloys are among the ultra-lightweight and workable alloys that have replaced some air alloys (such as 2000 and 7000 groups) due to their higher elastic modulus and lower specific gravity. Increasing the mechanical properties of these alloys using various thermal-mechanical methods (Thermo ...
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Aluminum-lithium alloys are among the ultra-lightweight and workable alloys that have replaced some air alloys (such as 2000 and 7000 groups) due to their higher elastic modulus and lower specific gravity. Increasing the mechanical properties of these alloys using various thermal-mechanical methods (Thermo Mechanical) has always been considered by researchers. Creating GP regions through low temperature aging processes has a great impact on the physical and mechanical properties of aluminum-lithium alloys. In this research, in the first part of the experiments, by performing natural aging and artificial aging at a temperature of 100 اد C, the formation and impact of these areas on the properties of the alloy were investigated. In the second part of the experiments, the precipitation of phase T1 during the aging process and the effective effect on the optimal time of the aging process at temperatures C150 and C190 for a sample of aluminum-copper-copper-lithium alloy sheet have been investigated. The results show that the formation of GP areas in the structure increases the hardness, strength and special strength of the alloy and by performing the aging process at higher temperatures and forming stable sediments, the process of increasing the hardness and strength continues while the special strength of the alloy decreases. It was found that the change in energy level in the range C250 to C300 is related to the deposition of phase T1 and the change in energy level in the temperature range C450 to C305 due to its dissolution in the alloy structure. The energy of the formation and dissolution activations of phase T1 in this study was calculated to be (kj / mol) 1/122 and (/ mol (kj3 / 130), respectively, which is equal to the activation energy of the penetration of the constituent elements of this phase (copper and lithium) in the network structure. It is aluminum.
Original Research Paper
Architecture
M.Z Kabir; A. Abrisham Foroushan Asl; M. Khan alipour
Abstract
The use of prefabricated panels is one of the new methods of building construction, which has recently been used in the construction of interior and exterior walls, loaders and separators, as well as flooring in construction. This system includes two layers of welded wire mesh. On both sides, a layer ...
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The use of prefabricated panels is one of the new methods of building construction, which has recently been used in the construction of interior and exterior walls, loaders and separators, as well as flooring in construction. This system includes two layers of welded wire mesh. On both sides, a layer of polystyrene is placed and connected to each other by cutters. In the next step, shotcrete concrete is sprayed on these wires and then the surface is polished. The use of 3D panels is increasing due to the importance of lightening, optimizing and saving fuel consumption. In this paper, the combined system of steel frame and lightweight prefabricated panels in the distance from the frame under cyclic loading is analyzed numerically and laboratory. The columns of the frames used are 2IPE120 and the beams are IPE120 and the wall has a height of 120 cm, a width of 64 cm and a thickness of 14 cm, which includes two layers of concrete with a thickness of 4 cm and a layer of polystyrene with a thickness of 6 cm. Numerical analysis is performed with the help of Perform software and in the next step, the formability obtained from numerical and laboratory analysis is compared. Combining a 3D panel system with a bending frame will increase the stiffness and lateral strength of the structure.
Original Research Paper
TVET
Z. Nasiri Gheydari; H. Lessani; A. Darabi; F. Totonchian
Abstract
The permanent magnet hysteresis motor has the advantages of both the hysteresis motor and the permanent magnet. This engine is ideal for applications for electric vehicles, compressor pumps, robots and precision industrial drives, such as inertial navigation systems and video recorders that require high-performance ...
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The permanent magnet hysteresis motor has the advantages of both the hysteresis motor and the permanent magnet. This engine is ideal for applications for electric vehicles, compressor pumps, robots and precision industrial drives, such as inertial navigation systems and video recorders that require high-performance soft, low-performance, and high-performance audio. . In this article, we will model and simulate this engine. We first derive the dynamic equations of the engine by considering the Foucault effect, and then we present the equations of its state for simulation in the SIMULINK / MATLAB environment. Finally, we compare the results of the simulation with the results of the numerical method and the finite element. This comparison shows a good match for these results. The method presented in this paper is time-limited, faster than the finite element method, and has acceptable accuracy.
Original Research Paper
TVET
A.R Dourandish; G.H Paygane; S. Agha Najafi; G.H. Dehghan
Abstract
The purpose of this paper is to examine the design method of a micro-constraint that, with proper performance, can automatically take a micro-part according to the important parameters of the reaction time and force, and after performing various steps on the part. Be. Release the piece and be ready to ...
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The purpose of this paper is to examine the design method of a micro-constraint that, with proper performance, can automatically take a micro-part according to the important parameters of the reaction time and force, and after performing various steps on the part. Be. Release the piece and be ready to take the next piece. The use of CMOS technology in the design of retaining walls and the use of SMA technology in the design of the retaining bracket and its replacement instead of other existing designs in optimizing energy consumption power and reaction time, as well as combining the last two technologies play an essential role in this article. Is responsible. In the following, the mentioned design is examined through stimulation modeling based on mass and spring system and using mathematical software, analytical equations of stimulus movement based on time are extracted so that the time of deformation of stimulus can be calculated as a parameter.
Original Research Paper
Architecture
S. Ali Mohammadi; F. Ali Moradi; E. Jabbari
Abstract
One of the most important pillars of optimized multi-purpose reservoir optimization models is the definition of a penalty or loss function. Due to the variety of operating goals and the complexity of the system, they often use alternative functions instead of using profit and cost functions, which only ...
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One of the most important pillars of optimized multi-purpose reservoir optimization models is the definition of a penalty or loss function. Due to the variety of operating goals and the complexity of the system, they often use alternative functions instead of using profit and cost functions, which only consider certain goals. These functions are the sum of several expressions that reflect the penalty or damages corresponding to the deviation from the desired values (needs). In this case, one of the most important steps in developing an optimization model is to determine the coefficients and capabilities (parameters) of these functions. This paper uses a dynamic stochastic programming (SDP) model to optimize the operation of a multi-purpose tank. With the help of this model, the parameters of the damage function have been evaluated through sensitivity analysis. For this purpose, the criteria of reliability, reversibility, and vulnerability have been used. Studies show that these parameters are much more sensitive to changes in the power of functions than the coefficients of functions.
Original Research Paper
Architecture
M. Hosseini
Abstract
Penetration is a very important feature in rocks and controls the flow of fluid inside the rocks. In most cells in mechanical laboratories, the water rock moves along the axis of the cylindrical pattern. These cells are used to determine the longitudinal permeability of the rock, while the fluid penetrates ...
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Penetration is a very important feature in rocks and controls the flow of fluid inside the rocks. In most cells in mechanical laboratories, the water rock moves along the axis of the cylindrical pattern. These cells are used to determine the longitudinal permeability of the rock, while the fluid penetrates radially into the rocks around the water and oil wells. The purpose of this study is to design a cell and calibrate a device used to determine the radial permeability of a rock. To test the performance of the test device, several experiments were performed on an artificial stone called CPIR09 as well as travertine. Test results show that the test device is performing well. Also, with the help of this test device, it is possible to measure the volumetric modulus of stone components.
Original Research Paper
Architecture
M. Yahyaee; M. Moradi
Abstract
Considering the purpose of Regulation 2800, which is to ensure the safety of life at risk level 1, as well as the progress made in the design method based on the performance and development of new design regulations, in this study, asymmetric steel structures in one In order to have a coaxial brace that ...
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Considering the purpose of Regulation 2800, which is to ensure the safety of life at risk level 1, as well as the progress made in the design method based on the performance and development of new design regulations, in this study, asymmetric steel structures in one In order to have a coaxial brace that is designed according to the 2800 standard of the third edition and the tenth issue of the national regulations, from the perspective of design, based on the performance and criteria of the Iran Improvement Instruction, Do or not. For this purpose, 12 steel buildings with coaxial brace system in groups of 5, 8, 11 and 14 floors are analyzed and studied by leaving the centers of difficulty compared to the center of mass 0, 10 and 20%, which is due to the displacement of braces in one direction. At the stage of performance appraisal, the results of static and dynamic nonlinear analysis of buildings, including relative displacement of floors, determination of structural performance point, paste deformations of compressive and tensile braces, and ratio of force to column capacity with acceptance, comparison and level criteria. The performance of buildings and their components has been determined. The results show that regular and irregular structures of 11 and 14 floors provide the level of life safety performance at risk level 1. This is almost true of 8-story structures, but in 5-story structures, especially in the symmetrical direction, weaknesses have been observed that need to be addressed to ensure the level of safety of the lifeguard.
