Microgrids dynamic stability interconnected through low voltage AC network

Renewable energy based microgrids have main challenges of maintaining its frequency-voltage characteristics and system becomes more complex when they are interconnected. These sources being intermittent in nature need to be supported by other resources like diesel/biogas such that at time of small variation in load or natural sources (wind/solar), power requirement is met through support provided by diesel/biogas-based system. Also, the controller should be fast enough to minimize the changes such that system reaches steady state. In this paper, renewable based rural microgrid consisting of wind, solar and biogas is modeled and interconnected through low voltage AC (LVAC) line. Also, one of the microgrid modeled is connected to the main grid as well as drawing power from the other microgrid. Control approach have been developed in such a way that whenever there is disturbance in the system due to increase/decrease in load or input to the renewable energy sources the biogas-based system of individual microgrid increases/decreases its generation to support the system requirement. No extra power is drawn either from the LVAC network or main grid as desired. modeling of system and its dynamic Study has been carried out in MATLAB/Simulink.

Flexible soft-output decoding of polar codes

In this research, we study soft-output decoding of polar codes. Two representative soft-output decoding algorithms are belief propagation (BP) and soft cancellation (SCAN). The BP algorithm has low latency but suffers from high computational complexity. On the other hand, the SCAN algorithm, which is proposed for reduced complexity of soft-output decoding, achieves good decoding performance but suffers from long latency. These two algorithms are suitable only for two extreme cases that need very low latency (but with high complexity) or very low complexity (but with high latency). However, many practical systems may need to work for the moderate cases (i.e., not too high latency and not too high complexity) rather than two extremes. To adapt to the various needs of the systems, we propose a very flexible soft-output decoding framework of polar codes. Depending on which system requirement is most crucial, the proposed scheme can adapt to the systems by controlling the level of parallelism. Numerical results demonstrate that the proposed scheme can effectively adapt to various system requirements by changing the level of parallelism.

Design and Development of an Intelligent Skipping Rope and Service System for Pupils

Regular physical activity (PA) contributes to health, growth and development in childhood and it is essential for children to achieve appropriate PA levels (PAL). However, most children around the world fail to comply with the recommended PAL requirements. Rope skipping, as a highly accessible, enjoyable, and affordable physical activity for students, has been considered a sustainable afterschool physical activity to promote physical fitness of students by educators. The booming development of smart fitness product design and the advent of exergames have brought new possibilities for physical education and rope skipping: personalized guidance, intuitive and interesting feedback and visualized exercise data analysis—there is much room for optimization. In this study, an intelligent skipping rope and its service system were studied for primary school students (aged 7–12) who started to get involved in this sport. First, user needs, product functions, and system requirement were summarized by conducting observations and user interviews. Then, a prototype of the hardware and software interface were designed based on analysis of user research. Next, a usability test of the interactive prototype was carried out and optimization was finally made based on the feedback of the usability evaluation. The final system design includes combined innovations in software and hardware with the intention to increase children’s participation in physical activity and assist them in skipping rope in the right way with proper equipment and programs.

Implementation of video surveillance system using embedded Blackfin processor

<p class="NormalLinespacing15lines">The video surveillance is critical system to track the people at the various places and to track and monitor the nuciencess bound to be happened. On the other side several studies have proved and showed the hit and miss nature of human intervention to spot change in a surrounding environment which increasing the designer challenges for the development of video surveillance system with the help of embedded processor. The designer faces a greater challenge to apply the principle of embedded systems and develop the system smart features with low power and cost for the required applications of VSS. System requirement specification (SRS), Hardware design document (HDD), Software design document and test procedure has been arrived and developed to achieve VSS system. Blackfin processor has high end video engines and is more suitable for development of video surveillance system (VSS). The VSS is designed and developed using ADSP BF533 Ez-kit lite board. Peripheral like parallel peripheral interface (PPI) is used to interface between camera and processor. Also, it is used for interfacing processor and TV. The master-slave communication is established between two Blackfin processors through SPORT to transfer the captured frame from camera to display on TV. Power management is also implemented to save the power of the system.</p>

System Requirement Specification of Mobile Apps for shrimp farming in Shyamnagar of Bangladesh

Frozen food is one of Bangladesh’s most valuable export items, comprising more than 80% of shrimp. The most cultivated area of shrimp is situated in the southern region of Bangladesh. This research was carried out to identify the core problem in the shrimp farming areas in order to support the related farmers in seeking a solution through the most common technology used by them. The study was conducted in Shyamnagar, Satkhira district with a total of 40 female respondents involved. This research showed that shrimp farming is pressurized by a lack of proper information on disease identification and its management. Mobile apps are considered the most common information providers among that community. The research defined the common problems and necessity through the system requirement specification (SRS) to provide needed details for the farmers that focused on mobile-app development eventually. It was found that disease (82.86%) and water quality (17.14%) are the most common issues while among the diseases White Spot Syndrome Virus and Yellow Head Virus Disease followed by Black Gill disease were the most alarming to handle without pre-management knowledge. The research also suggests developing voice-based mobile apps for shrimp farmers in the local language.