This paper presents a FACTS operation scheme to enhance the power system security. Three main generic types of FACTS devices are introduced. Line overloads are solved by controlling active power of series compensators and low voltages are solved by controlling reactive power of shunt compensators, respectively. Especially, the combined series-shunt compensators such as UPFC are applied to solve both line congestions and low voltages simultaneously. Two kinds of indices that indicate the security level related to line flow and bus voltage is utilized in this paper. They are iteratively minimized to determine operating points of the devices for security enhancement. The sensitivity vectors of the indices are derived to determine the direction of minimum. The proposed algorithm is verified on the IEEE 14-bus system with FACTS devices in a normal condition and in a line-faulted contingency.

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Stand-alone photovoltaic (SAPV) systems are being used in remote areas and are being seen as one of the promising solution in this regard. The SAPV system as presented in the paper consists of solar PV panel, a DC-DC converter, a controller and a PMDC motor. The current-voltage and power-voltage characteristics being nonlinear, the SAPV system require maximum power point techniques (MPPT) control techniques to extract maximum power available from the PV cell. A voltage based MPPT technique which is capable of tracking MPP has been selected because of numerous advantages it offers such as: simple and low cost of implementation. The limitation of constant voltage method is that its efficiency is low as the PV panel has to be disconnected from the load for measurement of the open circuit voltage (V_oc). In the presented paper, the authors have removed this limitation by using a pilot PV panel for measurement of V_oc. A proportional-integrator (PI) based controller is used in implementation of constant voltage MPP technique and the modeling is done in MATLAB^®/SIMULINK simulation environment. The simulation results are presented and discussed in the paper, the results shows that the efficiency of the system has increased.

<p><span lang="EN-IN">This paper presents a novel method for QRS detection. To accomplish this task ECG signal was first filtered by using a third order Savitzky Golay filter. The filtered ECG signal was then preprocessed by a Wavelet based denoising in a real-time fashion to minimize the undefined noise level. R-peak was then detected from denoised signal after wavelet denoising. Windowing mechanism was also applied for finding any missing R-peaks. All the 48 records have been used to test the proposed method. During this testing, 99.97% sensitivity and 99.99% positive predictivity is obtained for QRS complex detection.</span></p>

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Modeling and simulation of photovoltaic cells or PV cell is becoming important as it provides an easy platform to perform studies on photovoltaic cells and the design and analysis of the system based on photovoltaic cells. In this paper, we present our study of the ordinary photovoltaic module on the basis of one diode and two diode models. Studies are extended to solar cells as solar cells are similar to photodiodes. Performance of the solar cells may be described in terms of ideality factor (α), which decreases with temperature and is observed to affect the performance of the PV cell. PV systems exhibit better performance with diodes having higher values for α. In this paper, our efforts are to study the effects of α on Current and Power versus Voltage characteristics of the solar cells. MATLAB simulation of solar cell systems is a simple and elegant mechanism useful for designing and modeling the framework of the solar power plant

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