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Increasing thermal efficiency in diesel engines through low heat rejection concept is a feasible technique. In low heat rejection engines the high heat evolution is achieved by insulating the combustion chamber surfaces and coolant side of the cylinder with partially stabilized zirconia of 0.5 mm thickness and the effective utilization of this heat depend on the engine design and operating conditions. To make the low heat rejection engines more suitable for automobile and stationary applications, the extended expansion was introduced by modifying the inlet cam for late closing of intake valve through Miller's cycle for extended expansion. Through the extended expansion concept the actual work done increases, exhaust blow-down loss reduced and the thermal efficiency of the low heat rejection engine is improved. In low heat rejection engines, the formation of nitric oxide is more, to reduce the nitric oxide emission, the internal exhaust gas re-circulation is incorporated using modified exhaust cam with secondary lobe. Modifications of gas exchange with internal exhaust gas re-circulation resulted in decrease in nitric oxide emissions. In this work, the parametric studies were carried out both theoretically and experimentally. The combustion, performance and emission parameters were studied and were found to be satisfactory.

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Use of biodiesel in diesel engine is becoming popular due to its advantages such as eco friendly, green fuel, low cost and most importantly it is a renewable fuel. In the recent scenario of increased diesel fuel cost and environmental issues, the use of biodiesel in internal combustion engines in transport sector provides energy security along with environmental protection. The chemically treated vegetable oil called biodiesel can be produced from either edible or non edible oils through commonly known transesterification process. In this investigation, biodiesel produced from non edible jatropha oil has been used in a single cylinder water cooled stationary diesel engine to assess the performance and emission characteristics of the engine. The performance characteristics of biodiesel are similar to that of diesel fuel operation and emission levels are lower than the diesel fuel. The use of low cost biodiesel in diesel engines leads to same power output with lower emission levels which in turn leads to a global revolution in possessing a renewable fuel at stake and also assures energy security and environmental cleanliness.

Data gathering is a common but critical operation in many applications of wireless sensor networks. Innovative techniques that improve energy efficiency to prolong the network lifetime are highly required. Clustering is an effective topology control approach in wireless sensor networks, which can increase network scalability and lifetime. The framework employs distributed load balanced Clustering and dual data uploading, which is referred to as LBC. A distributed load balanced clustering (LBC) algorithm is proposed for sensors to self-organize themselves into clusters. We used mobile divider for split the data about cluster and cluster head calculation. In contrast to existing clustering methods, our scheme generates multiple cluster heads in each cluster to balance the work load and facilitate dual data uploading. The trajectory planning for Mobile collector is optimized to fully utilize dual data uploading capability by properly selecting polling points in each cluster. By visiting each selected polling point, Mobile collector can efficiently gather data from cluster heads and transport the data to the static data sink. Extensive simulations are conducted to evaluate the effectiveness of the proposed LBC schemes.