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Quantum-dot cellular automata (QCA) has attracted computer scientists as new emerging nanotechnology for replacement the current CMOS technology because it has unique characteristics such as high frequency, extremely small feature size and low power consumption. The main building blocks in QCA are the majority gate and inverter so any Boolean function can be represented using these gates. Many important circuits were the target for implemented in this technology in an optimal form, such as random-access memory (RAM) cell. QCA-RAM cells were introduced in literature with different forms but most of them are not optimized enough. This paper aims to demonstrate QCA inherent capabilities that can facilitate the design of many important gates such as the XOR gate and multiplexer (MUX) without following any Boolean function to get an optimum design in terms of complexity and delay.

In this paper, a novel structure of QCA-MUX in an optimal form will be used to design two unique structures of a RAM cell. The proposed RAM cells are the lowest cost required compared with different counterparts. The presented RAM cells used a new approach that follows the new suggested block diagram. The presented circuits are simulated and tested with QCADesigner and QCAPro tools.

The comparison of the proposed circuits with the previously reported in the literature show noticeable improvements in speed, area, and the number of cells. The cost function analysis results for the proposed RAM cells show significant improvement compared to older circuits.

A novel structure of QCA-MUX in an optimal form will be used to design two unique structures of a RAM cell.

Load forecasting is important to any electrical grid, but for the developing and third-world countries with power shortages, load forecasting is essential. When planed load shedding programs are implemented to face power shortage, a noticeable distortion to the load curves will happen, and this will make the load forecasting more difficult.

In this paper, a new load forecasting model is developed that can detect the effect of planned load shedding on the power consumption and estimate the load curve behavior without the shedding and with different shedding programs. A neuro-Fuzzy technique is used for the model, which is trained and tested with real data taken from one of the 11 KV feeders in Najaf city in Iraq to forecast the load for two days ahead for the four seasons. Load, temperature, time of the day and load shedding schedule for one month before are the input parameters for the training, and the load forecasting data for two days are estimated by the model.

To verify the model, the load is forecasted without shedding by the proposed model and compared to real data without shedding and the difference is acceptable.

The proposed model provides acceptable forecasting with the load shedding effect available and better than other models. The proposed model provides expected behavior of load with different shedding programs an issue helps to select the appropriate shedding program. The proposed model is useful to estimate the real demands by assuming load shedding hours to be zero and forecast the load. This is important in places suffer from grid problems and cannot supply full loads to calculate the peak demands as the case in Iraq.

This study aims to replace current multi-layer and coplanar wire crossing methods in QCA technology to avoid fabrication difficulties caused by them.

Quantum-dot cellular automata (QCA) is one of the newly emerging nanoelectronics technology tools that is proposed as a good replacement for complementary metal oxide semiconductor (CMOS) technology. This technology has many challenges, among them being component interconnection and signal routing. This paper will propose a new wire crossing method to enhance layout use in a single layer. The presented method depends on the central cell clock phase to enable two signals to cross over without interference. QCADesigner software is used to simulate a full adder circuit designed with the proposed wire crossing method to be used as a benchmark for further analysis of the presented wire crossing approach. QCAPro software is used for power dissipation analysis of the proposed adder.

A new cost function is presented in this paper to draw attention to the fabrication difficulties of the technology when designing QCA circuits. This function is applied to the selected benchmark circuit, and the results show good performance of the proposed method compared to others. The improvement is around 59, 33 and 75% compared to the best reported multi-layer wire crossing, coplanar wire crossing and logical crossing, respectively. The power dissipation analysis shows that the proposed method does not cause any extra power consumption in the circuit.

In this paper, a new approach is developed to bypass the wire crossing problem in the QCA technique.