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Personal communication methods in underground coal mines are far less sophisticated and efficient than surface level communication techniques. This deficiency can be attributed to the generally unfavourable and hazardous environment prevailing underground which acts as a deterring factor for their development. However, effective and reliable communication between underground coal mines and the control room on the surface is essential for safety and emergency rescue operations. Wireless communication is not a viable alternative because of the high attenuation profile as well as variation in the propagation path through uneven structures of underground coal mines and inflammable gases and moisture generally present there. Hence, wired personal communications using an existing structure such as power lines forms a very efficient and economical approach. This paper investigates the developments of communication in underground coal mines in India and presents an overview of the power line communication (PLC) technology. The possible use of PLC especially for deployment in underground coal mines in India is discussed in detail. [ABSTRACT FROM AUTHOR]

Polyhouse cultivation enables year-round production of bell pepper (Capsicum annuum L.). Maintaining a favorable micro-climate inside a polyhouse is mostly through manual operation of environmental control systems in developing countries, and to varying degrees, with automation in developed countries. In this study automation of micro-climate control through sensors and controllers was examined. Soil moisture, relative humidity, and air temperature sensors were installed at different locations inside a polyhouse for the operation of irrigation, foggers, and fan-pad cooling systems. Threshold values of these parameterswere set as input to the programmable logic controller and systems. Bell pepper is an economically important crop rich in nutrients. The efficacy of the use of an automated system to control the growing environment for this crop needs to be clarified. The experiment was conducted using cv. Swarna, grown under open-field and polyhouse culture, at irrigation levels of 80% or 100% of crop evapotranspiration. Type of growing environment affected yield and fruit size, with production in the polyhouse being better, but irrigation level did not. The programmable logic controller-based automation system worked well for micro-climate control leading to 93% and 53% higher yield and fruit weight, respectively, in the polyhouse than open-field cultivation. The programmable logic controller-based automation can aid in maintaining a favorable microclimate inside a greenhouse leading to better bell pepper yield. [ABSTRACT FROM AUTHOR]

In a developing country like India, necessary power infra structure has to be ramped up to meet the growing demand for power. Expansion of Transmission Network is an integral element in supplying power to the needy regions. Lack of transmission capacity in Tamilnadu in some areas, it is not able to evacuate wind energy to its full extent. In this paper, a multi objective function is incorporated which includes economic criteria as well as technical and adequacy criteria. Usually Economic criteria include the investment cost, the maintenance cost and the operation cost but due to market conditions it also includes cost escalation due to project delay, cost escalation due to inflation and cost escalation due to Right of Way. In this paper an approach for Transmission Expansion Planning (TEP) is formulated by introducing a Transmission Planning Index (TPI). TPI is formulated as a multi-objective function and optimized using different methods like Backward Search (BS), Forward Search (FS), Hybrid Search (HS), Genetic Algorithms (GA) and Bacterial Foraging Optimization Algorithm (BFOA). The proposed approach is validated by performing TEP for 133 Bus TNS (Tamil Nadu System). Congestion cost also evaluated for the different scenarios in this paper. [ABSTRACT FROM AUTHOR]