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An Independent Component Analysis (ICA)-basedimage enhancement technique is presented to improve the accuracy for machine reading of camera-based images. Images of inscriptions that are normally engraved on stones or other durable materials and found at the sites of historical monuments are taken as a reference for conducting the present experiments. Significant improvement in recognition rate of a commercial OCR system shows the potential of the proposed ICA-based method. It improves word and character recognition accuracies of the OCR system by 68.6% (from 11.2% to 79.8%) and 57.3% (from 34.8% to 92.1%), respectively.

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The principles of physics and system sciences are increasingly used in the field of network engineering to design network protocols. This work proposes an energy and congestion aware routing algorithm inheriting the concepts of potential field. It uses depth and time variant network parameters for forwarding the data packets through low congestion and energy balanced path. We defines a novel forward aware energy density as decision metric along with residual energy and queue-length for forwarding data packets. This results in network wide balanced residual energy and enhanced network lifetime. The proposed mechanism is evaluated for the transmission rounds before the first dead node (FDN) is detected. It was found that in typical traffic conditions there was an average increment of 45% transmission rounds till the FDN appeared. Moreover, the simulated and theoretical findings are compared using statistical measures to justify the proposed mechanism energy and congestion awareness.

Route estimation process often involves significant message exchanges among wireless sensor nodes while selecting the least cost path. Nodes along this path handle more traffic that leads to death of battery powered nodes and shortening network life. Thus, routing mechanisms for wireless sensor network (WSN) must be traffic aware and at the same time, the alternate route(s) incur less delay overhead. This paper considers a query-driven application scenario in WSN where the sink diffuses query over the network to fetch information. A novel field-based routing (FBR) mechanism is proposed that inherits the physical properties of Coulomb's law for point charges in free space. It defines a distance field parameter corresponding to each sensor node with respect to the sink. The sink being the negatively charged particle the packets from sensor nodes (positively charged particle) flow towards the field generating sink. The algorithm considers energy depletion rate for estimating the virtual potential field at nodes so as to avoid the nodes having less remaining energy. Further, the gradient updation is based on the local information which results in less message complexity (O(n)) and low computation overhead, which is comparable to the best available approaches. NS-2 based simulation demonstrates a significant enhancement in network lifetime, increased packet reception ratio and reduction in energy dissipation rate making the FBR mechanism suitable for WSN.