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This study addresses the optimal load flow problem for low-frequency transmission lines connected to wind farms and Pumped Storage Hydropower (PSH). The losses in the LF-HVac system and the voltage stability index are highly reliant on the operating frequency. Hence, it is essential to integrate an Optimal Load Flow (OLF) method in order to ascertain the appropriate solutions for these systems. The load flow solutions in this system involve the utilization of the Newton–Raphson method in conjunction with STATCOM. A proposed approach to simplify mathematical calculations involves the development of a two-port equivalent model for transmission lines. This model is based on solutions derived from the Telegrapher’s method. The OLF method, which has been proposed, has undergone testing with various algorithms and has been successfully implemented in the IEEE 39-BUS system. The obtained results demonstrate that the LF method, when combined with the proposed metaheuristic algorithm, achieves optimal frequency for low-frequency HVac systems while simultaneously ensuring system stability.

This paper solves the problem of localization for indoor environments using visual place recognition, visual odometry and experience based localization using a camera. Our main motivation is just like a human is able to recall from its past experience, a robot should be able to use its recorded visual memory in order to determine its location. Currently experience based localization has been used in constrained environments like outdoor roads, where the robot is constrained to the same set of locations during every visit. This paper adapts the same technology to wide open maps like halls wherein the robot is not constrained to specific locations. When a robot is turned on in a room, it first uses visual place recognition using histogram of oriented gradients and support vector machine in order to predict which room it is in. It then scans its surroundings and uses a nearest neighbor search of the robot’s experience coupled with visual odometry for localization. We present the results of our approach test on a dynamic environment comprising of three rooms. The dataset consists of approximately 5000 monocular and 5000 depth images.

This paper introduces a hybrid multilevel inverter (MLI) with reduced switch count, which can generate higher output voltage level with minimum number of DC input sources. The operation of this proposed MLI is carried out with unequal DC sources to achieve the desired output voltage level. The reduced MLI output voltage is set to minimal total harmonic distortion (THD) with the help of modified JAYA (MJAYA) algorithm. A JAYA algorithm with improved steps by adopting an accelerating parameter has been proposed in this research work to obtain a faster convergence of the objective function. The MJAYA algorithm has provided the suitable switching angles for the proposed three-phase 15-level MLI and reduced the output voltage THD to 2.23%, which satisfies the standard set by IEEE-519. To prove the efficiency of this proposed modified algorithm, the comparative analysis is carried out through MATLAB program and Simulink tool using common JAYA and modified particle swarm optimisation algorithms. The performance and productivity of the proposed MLI have been investigated through simulation and experimental setups. [ABSTRACT FROM AUTHOR]

The study introduces a unique control strategy combining multi-frequency control (MFC) and fuzzy PI control for LF-HVAC transmission systems. MFC is typically associated with microgrid applications, but here it's adapted for use in a different context - LF-HVAC transmission (low frequency high voltage alternating current). The proposed controller is shown to enhance system performance by reducing settling time and peak time of frequency fluctuations by small but significant percentages (0.12% and 0.15% respectively). These improvements contribute to better transient response and stability in LF-HVAC transmission systems. By minimizing power quality problems associated with frequency changes, such as total harmonic distortion (THD) of line voltage, the proposed controller enhances the overall quality and reliability of power transmission. This is particularly crucial in high-voltage transmission systems where maintaining stable voltage levels is essential. The study goes beyond theoretical simulations by validating the proposed model using both MATLAB simulations and real-time hardware-in-the-loop (HIL) simulations with Opal RT. This comprehensive validation process ensures the reliability and applicability of the proposed control strategy in practical LF-HVAC transmission systems. [ABSTRACT FROM AUTHOR]

The experiment was conducted to evaluatethe effect of age on sperm characters in semen stored at 4°C. Eighteen health breeding bucks of Jamunapari breed were selected and divided in three groups. Each group comprising 6 bucks of similar age viz.group I - young buck in age group of 15 to 25 months, group II -adult buck in age group of 35 to 45 months and group III -old buck from 55 to 65 months. All the selected buck exhibited mass motility of >4, live percent >85%, progressive motility >75 % and abnormality < 2% in fresh semen during routine collection and examination. Semen was collected biweekly from each individual buck in each group. With 3 ejaculates from each buck, a total of 18 ejaculates were collected from each group which were diluted using tris-based semen extender and store at 4°C. The semen samples were evaluated after 48 hours of storage. The results exhibited significantly (p<0.01) higher values for total viable sperm in group II and group I. The values recorded for mitochondrial activity, acrosomal integrity, plasma membrane fluidity, Hypo osmotic swelling test (HOST) and reactive oxygen species (ROS) unaffected sperm was significantly (p<0.01) higher in group II compared to group I and III. Total motile sperm and progressive motile sperm were significantly (p<0.01) higher in group II. VCL (µm), STR (%) were significantly (p<0.01) higher in group II while values for VAP(µm), VSL (µm), Lin (%) and BCF (hz) were non-significant in group II and group I which wassignificantly (p<0.01) higher than group III. The values recorded for antioxidative enzymes superoxide dismutase (SOD), catalase were significantly (p<0.01) higher in group II. MDA exhibited significant (p<0.01) difference in all group with lowest value in Group II. The result indicates that age of buck has a significant effect in regulating sperm character during semen storage at 4°C. Adult animal in age group of 36-48 months can be preferredas semen donor to collect, dilute and storesemen for its short-term use as insemination dose. [ABSTRACT FROM AUTHOR]