Quantum-dot Cellular Automata (QCA) technology is attractive due to its low power consumption, fast speed and small dimension, therefore, it is a promising alternative to CMOS technology. In QCA, configuration of charges plays the role which is played by current in CMOS. This replacement provides the significant advantages. Additionally, exclusive-or (XOR) gate is a useful building block in many important circuits such as full adder (FA). In this paper we propose a novel design for two-input XOR gate in QCA. Two-input XORs could be utilized in constructing three-input ones which are widely used. The proposed XOR gate is the smallest design among the two-input XORs and it achieves significant improvements in terms of complexity and latency in comparison to the only existing similarly designed gate. Contrary to the common designing method which uses the logic function of XOR, the gate is constructed based on explicit interactions between QCA cells. The simulation results have been verified using the QCADesigner. پرونده مقاله

Recommender Systems are part of our life nowadays. In almost every big business, recommender systems are suggesting items to users automatically. The only factor that traditional recommender systems take into account is accuracy. They try to estimate user-item ratings as accurate as possible to recommend the more preferable items to users. But from the supplier point of view, profit is the most desirable achievement. In this paper we have proposed a profit-aware recommender system based on the multi-objective genetic algorithm. Our proposed method consider two objectives at the same time: Profit and Accuracy. Profit is amount of profit that company will gain of selling items and accuracy measures how much recommendations are close to user preferences. the NSGA-II as the most successful MO-GA has been selected here and its Crossover and Mutation operations have been designed. Our method and traditional collaborative-filtering method have been implemented and tested on three different datasets: Movielens, Netflix and Yahoo. Results confirm that in both accuracy and net-profit our method prevail over CF method. پرونده مقاله

QCA is a kind of computational technology used for developing circuits in Nano sizes. Decreasing the dimensions of pieces has led to the increase of circuit sensibility and quantum circuits are more vulnerable to defects and radiations of the environment. Majority gate and NOT gate (inverter) are the two basic gates in QCA technology based on which almost all circuits are made. So far, a limited number of fault-tolerant majority gates have been presented and research in this particular field seems appropriate. In this research we intend to provide a comprehensive design of 3-input majority gate in quantum cellular automata for all possible faults: misalignment, missing, dislocation, and redundancy so that low overhead is added to circuit. The gate is made up of both 90-degree and 45-degree cells. The results of this study indicate that our proposed 3-input majority gate is more fault-tolerant to the defects compared to the formerly presented one. پرونده مقاله