Power Quality is an essential concern in the modern power system that can affect consumers and utility. The integration of renewable energy sources, smart grid systems and extensive use of power electronics equipment caused myriad problems in the modern electric power system. Current and voltage harmonics, voltage sag, and swell can damage the sensitive equipment. These devices are susceptible to input voltage variations created by interference with other parts of the system. Hence, in the modern age, with an increase in sensitive and expensive electronic equipment, power quality is essential for the power system's reliable and safe operation. Dynamic Voltage Restorer (DVR) is a potential Distribution Flexible AC Transmission System (D-FACTS) device widely adopted to surmount the problems of non-standard voltage, current, or frequency in the distribution grid. It injects voltages in the distribution line to maintain the voltage profile and assures constant load voltage. The simulations were conducted in MATLAB/Simulink to show the DVR-based proposed strategy's effectiveness to smooth the distorted voltage due to harmonics. A power system model with a programmable power source is used to include 3rd and 5th harmonics. The systems' response for load voltage is evaluated for with and without DVR scenarios. It has been noted that the proposed DVR based strategy has effectively managed the voltage distortion, and a smooth compensated load voltage was achieved. The load voltage THD percentage was approximately 18% and 23% with insertion 3 rd and 5 th harmonics in the supply voltage, respectively. The inclusion of the proposed DVR has reduced THD around less than 4% in both cases.
An abnormal behavior detection algorithm for surveillance is required to correctly identify the targets as being in a normal or chaotic movement. A model is developed here for this purpose. The uniqueness of this algorithm is the use of foreground detection with Gaussian mixture (FGMM) model before passing the video frames to optical flow model using Lucas-Kanade approach. Information of horizontal and vertical displacements and directions associated with each pixel for object of interest is extracted. These features are then fed to feedforward neural network for classification and simulation. The study is being conducted on the real time videos and some synthesized videos. Accuracy of method has been calculated by using the performance parameters for Neural Networks. In comparison of plain optical flow with this model, improved results have been obtained without noise. Classes are correctly identified with an overall performance equal to 3.4e-02 with & error percentage of 2.5.
This paper address the problem area of Unmanned Aerial Vehicles (UAV) emergency scenarios in which forced or emergency landing becomes imperative. Emergency or forced landing becomes crucial when there is system failure which impacts the flight safety and UAV is unable to fly back to the emergency landing runway. This failure could be due to data link loses, GPS failure, engine or flight surface failure. Forced landing needs to be performed on safe landing site which could be plane surface, open fields or grounds. First step to accomplish the successful forced landing safely is to search and select the safe landing site. This article presents the system design which assists the UAV in selection of safe landing site having no obstacles, buildings and trees. The proposed system design uses computer vision and machine learning techniques in order to classify feasible and non-feasible landing sites. The proposed algorithms in this article also incorporate the scenarios having low lighting conditions due to clouds. The system has been designed and simulated in MATLAB and promising results have been achieved with very less processing time and computational power.
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