Wet electrospinning of polyacrylonitrile (PAN) and dimethylformamide (DMF) with copper nanoparticles (CuNP) at different concentrations from 0.2 to 1 wt% have been studied under certain spinning conditions. A specific coagulating water bath has been used to collect different fibroses and fibril diameters, the effect of spinning height on the produced nanofiber and CuNP/PAN nanofibril composites have been studied from 1 to 7 cm heights. A minimum average diameter of 64 nm has been reported at 7-cm spinning height. Two heat treatment steps have been used to enhance the electrical properties of CuNP/PAN nanofibril composites. SEM has been used to study the morphological characteristics of the electrospun nanofibroses membranes. Preliminary electrical measurements using 4-point probing system showed a noticeable improvement in the electrical conductivity of the produced nanofibril composite membranes. Also, electrical property of a single CuNP/carbon nanofibril composite has been theoretically calculated based on Lichtenecker formula. The produced membranes have been used to build a micro surface-mounted components (MSMC) such as Micro Field Effect Transistor (MFET). A high transconductance has been reported for such a device which will open the door for many promising applications especially in Electronics and Biomedicine.

The combination of MIMO-OFDM is a very attractive solution for broadband wireless services. Thus, the two prominent fourth-generation (4G) cellular systems, WiMAX and LTE-advanced, have both adopted MIMO-OFDM transmission at the physical layer. OFDM signal however suffers from nonlinear distortions when passed through high-power amplifier (HPA) at the RF stage. This nonlinear distortion introduces out-of-band spectral broadening and in-band distortions on the transmitted signals. 4G cellular standards have placed strict limits on the allowable spectral broadening in their spectrum mask specifications, to insure that data transmission on a given channel is not interfering significantly with an adjacent channel user. In this article, we characterize the out-of-band spectral broadening introduced by HPA when MIMO-OFDM signals are transmitted over multiple relaying channels. Expressions for the power spectral density of MIMO-OFDM signals are derived over multiple relay channels, and the cumulative effects of HPA on the spectrum of the transmitted signals are estimated. It is shown that depending on the number of relays and the relaying configuration employed, it may happen that a transmitted MIMO-OFDM signal with the transmit spectrum mask initially within the allowable set limit at the source node arrives at the destination violating this limit due to the cumulative effects of the multiple HPA's in a multihop relaying channel.

Quantum circuits to realize color operations of channel of interest, channel swapping, and alpha blending on images are proposed using five kinds of quantum gates, i.e., NOT, CNOT, Toffoli, Rotation, and Controlled Rotation gates. Complexities of the proposed circuits are for an N-sized image, whereas the color information must be transformed pixel by pixel in the case of operators on classical computers. Simulations on the proposed three quantum color operations using three human facial and one Japanese style house images demonstrate that at most 9, 3, and 5 basic quantum gates are requested, that shows the feasibility of quantum circuits. Based on proposed three operations, all invertible classical color information transformation on imagesmay be designed and many applications can be realized on quantum computer, and the channel of interest based watermarking is being researched which the experiment results show that from the point of PSNR, our proposal is about 10 dB better than the chosen method of quantum image watermarking.

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A scheme is proposed to hide data in images based on a prioritised ordering of the content of the host image. The embedding process uses the watermark strength to determine the ordering of the 16 regions resulting from the second level wavelet transform DWT decomposed content of the host image. The DWT decomposed sub-bands of the cover image were analysed, transformed using the Pixel Value Difference (PVD), and then ranked in terms of their ability to withstand changes that do not imperil the visual quality (PSNR) of the watermarked image depending on which an N×N-sized watermark stream is hidden in the 8 highest ranked subbands. Using the proposal, a 256×256 Lena image had the capacity to accommodate up to 96800 bits of a watermark logo while still maintaining an appreciable visual quality manifested by a PSNR value of 33.66 dB.