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Brushless Direct Current (BLDC) motors are known as synchronous motors and used in industrial areas due to their advantageous features. NdFeB magnets used in BLDC motors and produced at different power levels of rare earth elements are preferred due to their excellent magnetic properties. Although physical factors and environmental conditions have an effect on permanent magnets, the performance values are determined by the maximum energy efficiency (BHmax), residual flux density (Br,) and intrinsic coercive force (Hei) parameters. In this study, Alnico, Ceramic, SmCo and NdFeB magnets used in BLDC motors with permanent magnet rotor structure and the effects of these magnets on motor performance parameters are analyzed. For motor performance, magnet types are compared by considering speed, efficiency and torque values. The magnetic properties of the NdFeB are determined by analysis comparisons. Therefore, the effects of the types of these magnets obtained at different power degrees (N28-N38-N42-N52) on the engine performance are included in the study by considering the operating conditions at different temperatures (20°C, 60°C, 80°C). In the study, the effects of NdFeB on motor heat transfer are determined by an inner mounted rotor IPMBLDC motor with 2.45 kW power, the analysis made with finite element method (FEM). [ABSTRACT FROM AUTHOR]

Historical buildings are an integral part of cultural heritage all over the world and are structures that carry the traces of the past to the present, together with the universal values they have. Although historical buildings, which generally have a masonry bearing system, have a better seismic performance compared to reinforced concrete structures, it is understood that some of these structures have suffered serious structural damage in some destructive earthquakes. Although many studies have been conducted to determine the seismic performance of historical buildings, there is no method that has been determined with strict lines to evaluate the performance of these structures. Within the scope of this study, a simplified method based on displacement was emphasized in order to determine the seismic performance of historical buildings and the seismic performance of historical Kaya Çelebi Mosque, which was damaged after the 2011 Van earthquake, was examined using this method. [ABSTRACT FROM AUTHOR]

This paper investigates the effect of own weight on the dynamic analysis of a pre-stretched composite platestrip containing a circular hole subjected to bending load. The combined effect of body forces (weight) and surface forces (pre-stretching load) on the plate-strip with a hole is considered as the initial stresses determined within the linear theory of elasticity. The effects of these initial stresses on the natural and forced vibrations around the hole within a plate-strip under additional bending load are investigated in the framework of the Three-Dimensional Linearized Theory of Elasticity (TDLTE) under the plane strain state, and the solutions of the considered boundary value problems are solved numerically by using the finite elements method. This paper shows that the influence of the plate's own weight has an important role on the dynamic analysis around the circular hole within a plate-strip. [ABSTRACT FROM AUTHOR]

This paper investigates the effect of own weight on the dynamic analysis of a pre-stretched composite plate-strip containing a circular hole subjected to bending load. The combined effect of body forces (weight) and surface forces (pre-stretching load) on the plate-strip with a hole is considered as the initial stresses determined within the linear theory of elasticity. The effects of these initial stresses on the natural and forced vibrations around the hole within a plate-strip under additional bending load are investigated in the framework of the Three-Dimensional Linearized Theory of Elasticity (TDLTE) under the plane strain state, and the solutions of the considered boundary value problems are solved numerically by using the finite elements method. This paper shows that the influence of the plate's own weight has an important role on the dynamic analysis around the circular hole within a plate-strip. [ABSTRACT FROM AUTHOR]

An artificial bedrock as wave impeding barrier can be used in practical civil engineering applications as isolation measures to protect structures from strong vibrations transmitted through soft ground nearby high-speed railway track. This study focuses on mitigation of the effects of high speed trains inducued vibrations on the strucutres which are located near the track lines by installing wave impeding barriers. Extensive parametric studies on the screening performance of wave impeding barrier have been done for both active and passive isolation cases. [ABSTRACT FROM AUTHOR]

In this paper, it is carried out the spread of plastic zones and the stress analysis at the composite plates with laminated thermoplastic (Polyvinyl Chloride) subsisting an elliptic hole in the middle part. The composite plates with steel fiber reinforcement of woven-shaped consist of four orthotropic layers bonded symmetrically in the form of [θ0-θ0]². The plates are subjected to uniformly distributed vertical loads. Loading is realized by iterations number of 25, 50, 75 and 100 by increments 0.0001 MPa by starting from the yielding point of plate for the chosen each reinforcement angle. According to the load steps and the different reinforcement angles, the values of the plastic stresses occurring in the composite plates are obtained by Finite Element Method. The obtained results present that the plastic zones in the plate appear in the lower and upper surfaces but not in the intermediate surfaces. It is also observed that the stress components at the intermediate layers are less than that of the lower and upper surfaces and the plastic stress components increase depending on the iteration number. [ABSTRACT FROM AUTHOR]