Enhanced photovoltaic performance of a dye sensitized solar cell with Cu/N Co-doped TiO<Subscript>2</Subscript> nanoparticles

Pure and Copper/Nitrogen (Cu/N)-codoped TiO₂ photoanodes with various Cu concentrations are prepared via sol–gel route for the photoanode application in dye-sensitized solar cells (DSSCs). All the prepared samples are characterized by X-Ray Diffraction (XRD), X-Ray Photoelectron Spectroscopy (XPS), Scanning Electron Microscope (SEM), Transmission Electron Microscopy (TEM), UV–Vis spectroscopy (UV–VIS) and Electrochemical Impedance Spectroscopy (EIS). Addition of suitable amount of Cu and N content in TiO₂ can alter its optical and electrical properties by extending absorption in the visible region and band gap reduction. The results show that some of the Ti sites are replaced by Cu atoms while O sites are occupied by N atoms. Upon adequate addition of Cu/N could lead to smaller particle size, higher specific surface area, increased dye adsorption and retarded charge carrier recombination. A significant improvement in the power conversion efficiency is observed in case of optimized 0.3 mol% Cu/N-doped TiO₂ nanoparticles (NPs) based DSSC. This optimized 0.3 mol% Cu/N-doped photoanode accomplished a best power conversion efficiency of 11.70% with a short circuit current density of 23.41 mA cm^?2 which is 41% higher than that of the pure TiO₂ photoanode based DSSC (6.82%).     

Study of the Choice of Excitation Frequency for Sub Surface Defect Detection in Electrically Thick Conducting Specimen Using Eddy Current Testing

Understanding the scope and limitations of non-destructive testing procedure is essential for selecting the appropriate test parameters for material inspection. This paper presents the scope of material (\( \delta_{s} \)) and probe dependent (\( \delta_{t} \)) penetration depths for determining the optimal test frequency (\( f_{opt} ) \) for detection of sub surface defects in electrically thick conducting specimens. Numerical modelling is carried out for a pancake coil above an electrically thick aluminium plate, \( t/\delta_{t} \)?>?1, to study the influence of the EC probe and defect location (\( t_{df} \)) on the test frequency for near and deep sub surface defects. The study concludes that the optimal test frequency, \( f_{opt} \) for detection of deep sub surface defects (\( t_{df} /t \approx 1 \)) is determined by the probe dependent skin depth, \( \delta_{t} \), and the plate thickness is related to \( f_{opt} \) by, \( t \propto 1/\sqrt {f_{opt} } \). The numerical observations were experimentally validated for machined sub surface notches on a 10 mm thick (\( t \)) aluminium plate.     

Formation of As–As Interlayer Bonding in the cT Phase of EuFe<Subscript>2</Subscript>As<Subscript>2</Subscript> and CeFeAsO Under Pressure from First Principle

The electronic band structure and structural phase stability of EuFe₂As₂ and CeFeAsO compounds were studied using the full-potential linearized augmented plane wave (FP-LAPW) method implemented using WIEN2k. To calculate the structural stability and phase transition of these compounds, the total energies have been computed as a function of reduced volumes and fitted with the Birch–Murnaghan equation. The calculated lattice parameters are found to be in agreement with the available experimental data. The present results show that EuFe₂As₂ and CeFeAsO compounds undergo structural phase transition from body-centered tetragonal (BCT) into collapsed tetragonal (cT) and tetragonal (T) into cT phase under pressure. The calculated phase transition pressures are in agreement with recent experimental data. The calculated valence charge density of collapsed tetragonal phase reveals that As–As interactions found to be stronger under pressure.     

A review on measurement science needs for real-time control of additive manufacturing metal powder bed fusion processes

Additive manufacturing technologies are increasingly used in the development of new products. However, variations in part quality in terms of material properties, dimensional tolerances, surface roughness and defects limit its broader acceptance. Process control today based on heuristics and experimental data yields limited improvement in part quality. In an effort to identify the needed measurement science for real-time closed-loop control of additive manufacturing (AM) processes, this paper presents a literature review on the current AM control schemes, process measurements and modelling and simulation methods as it applies to the powder bed fusion process, though results from other processes are reviewed where applicable. We present our research findings to identify the correlations between process parameters, process signatures and product quality. We also present research recommendations on the key control issues to serve as a technical basis for standards development in this area. Complimentary details to this paper with summary tables, range of values, preliminary correlations and correlation figures can be accessed from a National Institute of Standards and Technology Report (http://nvlpubs.nist.gov/nistpubs/ir/2015/NIST.IR.8036.pdf). This paper is developed based on the report.     

Multiclassifier for severity-level categorization of glioma tumors using multimodal magnetic resonance imaging brain images

Brain tumor segmentation and classification is a crucial challenge in diagnosing, planning, and treating brain tumors. This article proposes an automatic method that categorizes the severity level of the tumors to render an effective diagnosis. The proposed fractional Jaya optimizer-deep convolutional neural network undergoes the severity classification based on the features obtained from the segments of the magnetic resonance imaging (MRI) images. The segments are obtained using the particle swarm optimization that ensures the optimal selection of the segments from the MRI image and yields the core tumor and the edema tumor regions. The experimentation using the BRATS database reveals that the proposed method acquired a maximal accuracy, specificity, and sensitivity of 0.9414, 0.9429, and 0.9708, respectively.     

Reply to comment on “Dependence on charge transfer band and emission properties by the crystal chemistry of A- and B-site cations in Eu3+-doped quaternary pyrochlore-type red phosphors,Ca(RE)1−x(M)NbO7 (RE=Y,Gd; M=Ti,Sn)”

Journal of Materials Science: Materials in Electronics -     

Multimedia utilization of non-computerized disguised voice and acoustic similarity measurement

Multimedia Tools and Applications - In this paper, an identification of a speaker for multimedia application under non-electronically disguised voice is performed. In non-electronically disguised...     

Performance Analysis of MSFRLS-VFF Based Real-Time Adaptive Noise Canceller with RLS and APA Algorithms Using TMS320C6713 Processor

Wireless Personal Communications - In this paper, the real-time adaptive noise canceller (ANC) system is implemented using modified sigmoid function variation based recursive least square with...     

ZLBM: zero level binary mapping technique for video security

In recent days, providing security to data is a crucial and critical task in many image processing applications. Specifically, video security is an important and demanding concept. For this purpose, some of the embedding, encoding and decoding techniques are mentioned in existing works, but it has some drawbacks such as increased time complexity, computational complexity and memory consumption. Moreover, it does not provide high security during video transmission. To overcome all these issues, a new technique, namely, Zero Level Binary Mapping (ZLBM) is proposed in this paper for video embedding scheme. The motivation of this paper is to provide high security during video transformation by using the video steganography technique. At first, the cover and stego videos are given as the inputs and it will be converted into the video frames for further processing. Here, the Fuzzy Adaptive Median Filtering (FAMF) technique is employed to remove the impulse noise in the video frames. Then, the pixels in the filtered frames are grouped by using the block wise pixel grouping technique. After that, the frames are embedded with the help of ZLBM technique and encoded based on the patch wise code formation technique. On the receiver side, the inverse ZLBM and block wise pixel regrouping techniques are applied to get the original cover and stego videos. The novel concept of this paper is the use of ZLBM and patch wise code formation techniques for video embedding and compression. The main advantages of the proposed system are high security, good quality and reduced complexity. The experimental results evaluate the performance of the proposed video embedding technique in terms of Peak Signal-to-Noise Ratio (PSNR), Mean Squared Error (MSE), Compression Ratio (CR), Bits Per Pixel (BPP) and Signal-to-Noise Ratio (SNR).     

Bilingual text detection from natural scene images using faster R-CNN and extended histogram of oriented gradients

Pattern Analysis and Applications - In today's world, scene text detection is important for a wide range of scientific and industrial processes. Compared with text detection in documents, text...