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This paper describes a very fast method of calculating the power factor (p.f.) for a power line. Only two progressive samples of the current and voltage are required to execute the measurement. A phase locked loop (PLL) frequency multiplier scheme allows for an accurate measurement independent of the power line frequency fluctuation.I.

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With the growth of networked system and applications such as eCommerce, the demand for effective internetsecurity is increasing. Cryptology is the science and study of systems for secret communication. It consists of twocomplementary fields of study: cryptography and cryptanalysis.The genetic algorithm is one of the search methods, whichfinds the optimal solution. It is one of the methods, which is used to decrypt cipher.This work focuses on using GeneticAlgorithms to cryptanalyse knapsack cipher. The knapsack cipher is with a knapsack sequence of size 16 to encrypt twocharacters together. Different values of parameters have been used: Population size, mutation rate, number of generation.

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During recent years, nonlinear power electronic equipments introduce harmonic pollution on electric power systems. It makes the traditional power factor meter can not act accurately when it monitors unbalanced and harmonic loads. In this paper, a new algorithm for detecting the power factor in presence of non-sinusoidal load current is proposed. The proposed algorithm detects the true power factor exactly. By uses only two successive sampled data points of the voltage and the current for each displacement power factor value calculation and two sampled data points for each distortion power factor value calculation, the total/true power factor becomes easy to measure using these values directly. The proposed detector implemented using microcontroller as a main part and has been tested for single phase power system. The test results show that it can measure the true power factor of the loads quickly and accurately.