In this paper, a novel risk-based, two-objective (technical and economical) optimal reactive Power dispatch method in a wind-integrated Power system is proposed which is more consistent with operational criteria.  The technical objective includes the minimization of the new voltage instability risk index. The economical objective includes cost minimization of reactive Power generation and active Power loss. The proposed voltage instability risk employs a hybrid possibilistic (Delphi-Fuzzy)-probabilistic approach that takes into consideration the operator’s experience, the wind speed and demand forecast uncertainties when quantifying the risk index. The decision variables are the reactive Power resources of the system. To solve the problem, the modified multi-objective particle swarm optimization algorithm with sine and cosine acceleration coefficients is utilized. The method is implemented on the modified IEEE 30-bus system. The proposed method is compared with those in the previously published literature, and the results confirm that the proposed risk index is better at estimating the voltage instability risk of the system, especially in cases with severe impact and low probability. In addition, according to the simulation results compared to typical security-based planning, the proposed risk-based planning may increase the security and economy of the system due to better utilization of system resources.

Wheelchairs are essential for enhancing mobility in people with disabilities, but traditional models often lack advanced functionality and safety features. This study presents a smart wheelchair system that overcomes these limitations by integrating smartphone control via Bluetooth, using the Arduino Uno R3 microcontroller. The research addresses key challenges, including ensuring smooth control and safety in varying environments. The developed smartphone application, created using visual block programming, communicates with the Arduino system, which is coded in C++. This setup enables users to control the wheelchair’s movement through commands sent to DC Motors, while an ultrasonic sensor detects obstacles, enhancing safety. Rigorous testing demonstrated the system’s reliability, with the ultrasonic sensor achieving a deviation of only 0.3 cm. The wheelchair supports users up to 53 kg, achieving a speed of 0.28 m/s, with performance decreasing for heavier users. The contributions of this study lie in the integration of advanced control and safety features, enhancing mobility, efficiency, and user safety, making it an innovative solution for users with limited physical capabilities.

Brushless DC (BLDC) Motors are used in a wide range of applications due to their high efficiency and high Power density. In this paper, sensorless four-switch direct Power control (DPC) method with the sector to sector commutations ripple minimization for BLDC Motor control is proposed. The main features of the proposed DPC method are: (1) fast dynamic response (2) easy implementation (3) use of Power feedback for Motor control that is much easy to implement (4) eliminating the torque dips during sector-to sector commutations. For controlling the Motor speed, a position sensorless method is used enhancing drive reliability. For reference speed tracking, a PI control is also designed and tuned based on imperialist competition algorithm (ICA) that reduces reference tracking error. The feasibility of the proposed control method is developed and analyzed by MATLAB/SIMULINK® . Simulation results prove high performance exhibited by the proposed DPC strategy.

In this paper, a new method for extending and relaxing the noise-coupling (NC) technique is proposed to enhance the noise-shaping order without adding the number of integrators. The noise-shaping order of the introduced ∑∆ modulator whit applying a second-order noise-coupling technique is enhanced and its performance with optimizing the noise transfer function (NTF) zeros is improved. Also, by removing the analog adder at feedforward path and transferring it to a new feedback branch before the last integrator and adding second-order NC path can be decreased the input voltage swing to the quantizer. Thus, by improving the modulator resolution, Power consumption can be reduced. Mathematical analyses and behavioural simulation results confirm the effectiveness of the new NC method. To examine its performance, a 2nd-order single loop ΣΔ modulator was designed. The new noise-coupling method is used to achieve the three-order noise shaping to increase the resolution with low complexity and low-Power. The results show an outstanding improvement in signal-to-noise and distortion ratio (SNDR) compared to the conventional structure.

During the past decade laser has become an effective means for treatment of illnesses. Low Power laser has been used widely for treatment of lesions of soft tissues, arthritis, relief of pains, wound healing, etc. Although, the mechanism of its analgesic effect is not clear yet, probably nerve latency changes have some effects on pain conducting fibers. In this experimental study, the effects of irradiation of low Power infrared laser of Ga-Al-As with wavelength of 830 nm were studied on median nerve latency of 42 healthy people of 20-30 years old. The latency of Motor branch of the nerve was measured before irradiation, then left forearm in the area of the nerve was exposed to laser irradiation with energy densities of 1.5 j/cm2 and 6 j/cm2 per point. Temperature changes were controlled during the study and the latency was measured after stopping irradiation as well. Paired t-test showed a significant increase in the latency after laser exposure (P<0.001). This effect remained for a while after stopping irradiation. These findings could prepare a background for other studies using laser for treatment of some neurological disorders.

Close encounters with the Western culture and art starts under the Qajar rule. In this period, art elements of the West find their way in the Persian art and architecture. This paper reports the results of a survey of Window-guards extant form the Qajar period in Hamadan City. Of an initial sample of 68 Windows, 26 samples were selected for not being a repetition of other designs. These show a gradual evolution in technique and style of using wrought iron in four phases.In the first phase, a pattern formed with S-shaped elements covers the rectangular area of a Window, while the semicircular area under the spanning arch is usually blocked. In the second phase, by modifying the ‘S’ element, all the Window area is covered. In the third phase, the S element is further modified, its tips become convoluted and its proportions are freely changed to fill rectangular areas. In the fourth phase, the Window-guard is treated as a decorative architectural element. Therefore, in addition to the S element, other decorative spiral elements are used.