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Frequent power cuts necessitate the use of battery fed inverters in many homes and small industries in countries like India. Due to several charge and discharge cycles, the batteries have a typical life of 3 - 4 years. In this paper, a solar PV based retrofit solution is proposed which can be used along with these inverters. This solution uses a bi-directional DC to DC converter which charges and discharges the battery in the presence and absence of solar radiation respectively. The converter has been implemented using a simple add-on circuit with the main battery inverter. The proposed solution has the potential of providing high-quality power, grid connectivity, energy saving and enhancing the battery life. An analysis showing the effective energy saving using the proposed scheme has been presented. Simulations and experimental results have been obtained, and some representative results are included.

In this paper a hybrid algorithm that monitors the voltage at the Point of Common Coupling (PCC) and dispatches the optimal power from battery integrated micro grid is proposed. The proposed architecture integrates a rule based dispatch and a predictive optimization algorithm and ensures optimal power dispatch with minimum voltage variations at the PCC. The methodology and the algorithmic flowchart are discussed first and then the linked systems optimal power dispatch capability is assessed.

The use of cellular phones and hence its infrastructure has been growing very rapidly across the globe. The power system for a cell phone tower needs uninterrupted power supply. Hence its power system relies heavily on batteries and Diesel Generator (DG) sets — especially at those places that do not have a regular power grid. The batteries need heavy maintenance and do not work well at high temperatures. They also have a short life span. In this paper, a PV based system solution is proposed which can be retrofitted in the existing power system of the cell phone towers. This solution makes use of ultracapacitors and reduces the use of batteries. The implemented control scheme facilitates MPPT of the PV source, easy integration of the ultracapacitor stack into the system and seamless transition from grid-tied mode to islanded mode and vice versa. Mathematical modeling and system design for a 3kW cell tower power system are presented. The model is validated using simulation results. All the results of this work are presented.

System Identification has been widely used in obtaining the mathematical model of nonlinear systems. Nonlinear system identification is challenging because of its complexity and unpredictability. The nonlinear system considered in this paper is Rotary Double Inverted Pendulum which is unstable and non-minimum phase system. Inverted pendulum is a well-known benchmark system in control system laboratories which is inherently unstable. In this work full dynamics of the system is derived using classical mechanics and Lagrangian formulation. Artificial neural network is used to identify the model.

System Identification has been widely used in obtaining the mathematical model of nonlinear systems. Nonlinear system identification is challenging because of its complexity and unpredictability. The nonlinear system considered in this paper is Rotary Inverted Pendulum which is unstable and non-minimum phase system. Inverted pendulum is a well-known benchmark system in control system laboratories which is inherently unstable. In this work full dynamics of the system is derived using classical mechanics and Lagrangian formulation. Artificial neural network is used to identify the model.

Data burst contentions occur in optical burst-switched (OBS) networks due to one-way signaling and bufferless nature of the core network. A single burst loss containing multiple TCP segments can trigger drastic reactions from the corresponding TCP sources. TCP sender interprets segment loss as network congestion, resulting in throttling send rate. In this paper, we propose a new forward segment redundancy (FSR) mechanism that minimizes segment loss during burst contentions in the core and also recovers from segment loss in the forward direction using redundant segments placed in each data burst. In FSR mechanism, redundant TCP segments are added to each burst assembled at the ingress node before transmission to the destination. The segment losses due to contentions are minimized using a modified burst segmentation mechanism, and most lost segments are recovered in the forward direction using redundant segments. Using FSR, we observe significant improvement in TCP performance over OBS networks.

Computational methods for replication origin prediction in individual herpesvirus genomes have been previously devised based on the locations of high concentrations of palindromes. In order to make use of similarities in genome composition and organization of related herpesviruses, an artificial neural network approach is explored. We implement feed-forward artificial neural networks trained by 17 input variables comprising the positions of known replication origins relative to the genome lengths and the dinucleotide scores. The overall prediction accuracy of the neural network approach for our data set is better than that of the palindrome based approach. Furthermore, suitable combinations of the prediction results given by the two approaches substantially increase the prediction accuracy achieved by either method applied individually.

TCP-over-OBS is a promising transport paradigm to support next-generation-Internet. Load-balanced OBS improves loss- performance. We identify the ill-effects of load-balancing on TCP-performance due to false-time-outs and false-triple-duplicates. We propose source-ordering to improve TCP-throughput by three-four times.