The inaccurate estimation of the Initial rotor position in a synchronous reluctance motor can lead to reduced starting torque and slower rotor speed response at startup. Various methods have been proposed to estimate the Initial rotor position of the synchronous reluctance motor, which can be categorized based on complexity, implementation, and estimation accuracy. Some of these methods, despite their high implementation complexity, reduce the error in estimating the Initial rotor position. On the other hand, some methods are advantageous due to their low computational burden and ease of implementation, but they exhibit a higher error in estimating the Initial rotor position, with some methods showing errors of up to 30 degrees. This paper examines the impact of Initial rotor position estimation errors on the performance of synchronous reluctance motors from various aspects. To analyze the effect of estimation errors on the motor's parameters, errors of 0, 10, 20, and 30 degrees in Initial rotor position were applied, and the resulting impact on parameters such as electromagnetic starting torque and rotor speed response time to the reference speed were investigated. The simulation results were presented using MATLAB/Simulink software.

Abstract Intuition is one of the characteristics of entrepreneurs and an important factor in the decision-making processes of entrepreneurs. In recent years, at the same time as the development of entrepreneurship as an interdisciplinary science, intuition and providing different definitions of it have not been noticed by researchers and researchers in this field, and many researches have not been written in this field. This is despite the fact that in other fields of humanities, especially management (with which entrepreneurship is closely related), basic sciences and even medical sciences, there is a suitable background and theoretical literature about this. On the other hand, it seems that the theoretical and epistemological foundations of this concept have not been researched as much as necessary in the few researches that have been conducted, and very little research has been done in this field. In this article, firstly, the definitions and researches about intuition are reviewed, and secondly, the little researches that have been done in entrepreneurship and its relationship with other sciences are discussed.

This paper presents the design of a complete self-tunable method for detecting the rotor position at low, high, and standstill speeds under different motor power ratings in a switched reluctance motor (SRM). In this method, high frequency diagnostic pulses with different pulse widths are applied to the three-stator pole windings and then the proper size pulse width is determined for that particular motor at standstill. At low speeds, the rotor positions are then sensed with the selected pulse width by applying the pulse to the un-energized phase winding while sensing the rotor position from the resulting phase winding current magnitude. At high speeds) beyond motor rated speed) the rotor position is detected by the current magnitude produced by the injected pulse and at the same time advancing the phase on time according to the motor speed. The designed controller is tested on different motor ratings ranging from 20 W to 2 KW. In order to demonstrate the feasibility and practicability of the method, this controller is applied in a vacuum cleaner with a switched reluctance motor.

The rotor of Enegelberg whitener was equipped with a screw conveyor to reduce broken rice percentage. According to preliminary experiments this modification could reduce broken rice percentage about 2.5%. Further experiment was performed to determine the effect of rotor speeds and blade positions on white rice quality. To do this, five rotor speeds, consisting 500, 600, 700, 800 and 900 r.p.m and three blade positions including, distance blade from entrance side of rotor was 7mm and from exit side was 9mm, distance blade from entrance side and exit side was 8mm equally, finally distance blade from entrance side of rotor was 9mm and from exit side was 7mm were examined using a experiment factorial randomized complete block design. The considered white rice quality measures were percentage of whole rice, broken rice, degree of milling and performance index. According to the result, rotor speed had significant effect on whole white rice and broken rice in level of 5%. Blade position and the interaction of rotor speed and blade position had significant effect on degree of milling and performance index at level of 1% and 5% respectively. Based on the results, the optimum operating conditions were 600 r.p.m and  distance blade from entrance side of rotor was 9mm and from exit side was 7mm. The rotor speed of 800r.p.m leads to same result.

This paper presents an approach for life estimation of helicopter main rotor shaft based on the standard Federation aviation administration (FAA) spectrum. According to Federation aviation regulation (FAR), the safe life approach has been employed in order to estimate the shaft life. Since the loading of the shaft is non-proportional and the material ductility is low, Findley's critical plane criterion has been applied. In order to apply Findley's criterion, an individual code was developed using ANSYS Parametric Design Language facilities. The code uses the minimum circumscribed circle approach to calculate the amplitude of shear stress and finds the critical plane. The lives of the shaft for the most severe maneuvers and for the standard FAA spectrum were found to be 76 and 1090 flight hours respectively. The fatigue sensitivity chart has been plotted and the effect of replacing another material with the shaft material on the life of shaft has been studied. To validate the result, the life of the shaft in the critical node has been calculated according to federal administration aviation AC 27-1B. Good agreement with these two results was observed.

This paper introduces a new sensorless rotor position detection technique with the mechanical load asymmetric error determines ability for switched reluctance motor drives. In presented paper combination of pulse injection technique and digital pulse position modulation are employed for control of SR motor. In this method, a single high-frequency pulse is injected in an idle phase to determine the rotor position and estimates the rotor position through analysis of the resultant current after voltage pulse injection. Since the number of injected pulses is constant, in terms of the proper functioning of the motor, output bit stream has a fixed length and is proportional to the mechanical load torque. In the event of mechanical failure as a result of fluctuations in the mechanical load, the number of bits according to the error rate will change, which counts the number of output bits detection circuit, errors in mechanical load is determined. Proposed method decrease the injuries caused by asymmetry error in mechanical load connected to the motor shaft. The proposed sensorless method has been simulated using Matlab-Simulink and implemented on an experimental setup in real time to validate its performance. The results obtained demonstrate the feasibility and practicability of the method.

Single-phase motors are among the most widely-used motors in low-power applications. These motors are omnipresent in residential applications and make up a majority of this sector. Previously these motors were specifically employed in constant velocities. Over time the need for speed control in these motors has brought this problem into focus of many research investigations. Sensorless control of single-phase motors is particularly appealing due to mechanical and economic considerations. In the present paper, one attempts to control motor speed by influencing rotor flux orientation through a vector control method and propose a new method of speed estimation based on extended Kalman filter algorithm. In order to estimate single-phase induction motor speed together with on-line rotor resistance estimation, the measurement noises have been accounted in EKF algorithm. The proposed method is validated with a simulation that includes rotor resistance changes and measurement noise.

Simple structure and high maneuverability of quadrotors have made them one of the most preferable types of UAVs (Unmanned Aerial Vehicle). However, the main problem is their small payload capacity. In this paper, a novel five-rotor UAV is introduced. Dynamical model of UAV and two nonlinear controllers for trajectory tracking are developed. In the proposed UAV structure an extra propeller is added to the center of vehicle to improve the ability of lifting heavier payloads and open loop stability of quadrotor. The dynamic model is obtained via Newton Euler approach. The model is under actuated, nonlinear, unstable, and has strongly coupled terms. In order to have trajectory tracking two types of nonlinear controllers are designed for the UAV. First controller is designed based on input-output feedback linearization method. This controller involves high-order derivative terms and turns out to be quite sensitive to noises and modeling uncertainty. Second controller is a back-stepping controller based on the hierarchical control strategy that yields lower computational expense. Simulation results confirm acceptable performance of back stepping controller stability, position tracking, and robustness in presence of external disturbance.

The main task of the study is to estimate the position error in an inertial navigation system by integrating it with the visual system. The case study is a spacecraft that must accurately measure its position relative to a predetermined landing point. The spacecraft is assumed to be augmented GNSS navigation. Therefore, when satellite signals are dropped out or when landing on a moving marine platform, the data of the vision navigation system replaces the information of the satellite navigation system and improves the accuracy of the spacecraft navigation system. An Extended Kalman filter has been used to integrate inertial and vision navigation system information. In addition, the output data of the vision system, in order to be used in the Kalman filter measurement equations, is first processed by the recursive least square filter. The relevant relations are given and based on the results of software simulation, the efficiency of the proposed method is shown.