Search

Polarimetric SAR (PolSAR) has been widely used as an active imaging remote sensing technique to characterize manmade and natural features. The PolSAR data needs to be corrected from the polarimetric distortions to minimize the ambiguities for the accurate information retrieval of scatterers. The present work is focused on the minimization of system-induced and atmosphere-induced errors from PolSAR data. A new software Polarimetric SAR Calibration & Processing Tool v1.0 (PSCP v1.0) has been introduced for processing of fully polarimetric and hybrid polarimetric SAR data. The PSCP v1.0, a software tool will be available for the scientific community to calibrate and process the fully polarimetric and the hybrid polarimetric space borne and airborne SAR data of current and future missions of ISRO, India and also for other space agencies.

Polarimetric decomposition is a technique to decompose the radar imagery in the sub-pixel level to identify the underlying scattering mechanism. Polarimetric Synthetic Aperture Radar interferometry (PolInSAR) combines interferometric coherence with the Polarimetric decomposition model to improve its performance, especially in urban areas. The volume scattering model is very crucial in developing the decomposition model so as to reduce the ambiguity in identifying the target. Here cosine square probability distribution function is used to design the volume scattering model by incorporating the estimated polarization orientation angle. The proposed model combines the cosine square distribution and coherence based volume model to improve the performance of decomposition for urban and natural features.

Graduate Aptitude Test in Engineering (GATE) is an important examination in which around 1 million Indian engineering students register for seeking admission into renowned technical institutions of the country and for finding jobs in state-owned Public-Sector Undertakings (PSU). Through the application of learning analytics and educational data mining, a large dataset of 1039 students was analyzed to gain insights into factors leading to a successful examination.

A dual two-level inverter utilizes an open-end winding induction motor (OEWIM) to synthesise three level output voltage. In this paper, a model predictive control (MPC) technique namely predictive current control (PCC) method is proposed for the OEWIM. MPC techniques are seen as an alternative to the use of traditional proportional-integral based controllers. The PCC strategy is primarily based on prediction of stator current in the α − β plane and the objective function is accordingly formulated. In addition, switching commutations in the dual two-level inverter drive, common mode voltage in the OEWIM, etc. are carefully incorporated as control variables in the objective function with the proposed PCC strategy. Weighting factors of these variables are carefully designed in order to accomplish - minimum switching commutations in the dual two-level inverter drive and complete elimination of CMV. The proposed PCC is simulated using MATLAB/Simulink and is verified experimentally using a TMS320F28377s digital controller under various test conditions like speed change, speed reversal and load disturbances.

Multiple Online Social Networks and its applications have emerged rapidly at a large scale made dependence of global population on it for various reasons. The individuals data in each social network is just partial. Mapping these individuals across various online social networks is having more importance in forming communities and identifying the most influential node. The difficulties of fragmentary data which is the biggest challenge in the present social network era can be solved by forming groups and comparing their information which can be useful in several applications like influential node detection, spammer identification etc. The occurrence of different characterization of users leads in identifying the influential community by classifying them from other communities. Decision tree technique is used in splitting into different communities from multiple social network. Various number of trees are generated by changing class labels. Greater the performance metrical values (accuracy, precision, recall, f1-score) of the tree is considered for the effective formation of communities. Experimental results of the proposed method achieves 0.54, 0.58, 0.54, 0.54 in accuracy, precision, recall, and f1-measure, respectively.

In dynamic informal networks change the information prevailing inside them in perspective with time. An approach to distinguish the information existed in each nodes was achieved by recognizing the subnetworks or Communities inside the network through Community-Based models. To increase the utility capacity also estimated the degree to networks that are founded. The information about the networks will be not known and consequently the nature of the topology and instability data inside a Dynamic Social Network(DSN). It maximized the cost of finding the communities from the large networks and to reduce the cost expenditure in finding the communities; a novel greedy based approach has been proposed. The K values determine the total number of communities that are to be formed. The Network-based model foresee the individuals from the networks proposed strategy will likewise distinguish the network -based model that can catch the qualities of basic opening spanners productively and decline the connection upkeep cost in the extensive scale systems. An decrease in the cost of finding the optimal communities in comparison with the existing hierarchical and Clique census community detection approaches was achieved by the Top-k greedy approach with an optimal cost percent of 42.6.

Optimal route selection based upon Quality of Service (QoS) requirements is a challenging task in a completely dynamic environment like MANET. To enhance the quality of service in MANET, route selection plays an important role. Existing well known routing protocols like AODV, DSR, etc. does not choose path based on QoS parameters. Different applications has its own requirements for route selection like for Email and File transfer application, less retransmissions should be there while delay can have secondary importance and for video conferencing applications, bandwidth must be high and delay must be low. So, there is an uncertain environment in which same QoS parameter may have less or more importance as per the application. Fuzzy based approach plays a vital role in an uncertain environment like adhoc network in which nodes are mobile. In this paper, Fuzzy TOPSIS (multi-criteria decision making method) based approach is proposed for the selection of optimal path among N available routes from source to destination based on QoS parameters. Total four QoS parameters are considered here reliability, bandwidth jitter and delay. AOMDV routing protocol is the base protocol for the proposed system and the proposed protocol QoS-AOMDV is finally compare and analyzed with AODV, AOMDV protocol. QoS- AOMDV results in better throughput and delay as compared to AODV and AOMDV protocols.

Mobile ad hoc networks (MANETs) have inherently dynamic topologies. Due to node mobility, the links along the paths suffer frequent failure and reactivation in highly dynamic environments. A new routing paradigm, known as Opportunistic Routing (OR) has recently been proposed that finds routes in adaptive manner, based on current channel conditions in dynamic wireless environment. OR is based on the use of broadcast transmissions to expand the potential forwarders that can assist in the retransmission of the data packets. In this paper, we embark upon the basic operations of OR and a framework to support decision making for finding optimal route in the MANET. In later part we propose an adaptive algorithm to deal with OR as a Markov decision problem (MDP). Finally the comparative analysis of the proposed Markov chain based protocol with OR protocol: CORMAN has been carried out on the basis of throughput, average delay and control overhead. The proposed protocol shows the better results as compared to existing one.