Current transformer (CT) saturation is one of the significant problems for protection engineers. If CT saturation is not tackled properly, it can cause a disastrous effect on the stability of the power system, and may even create a complete blackout. To cope with CT saturation properly, an accurate detection or classification should be preceded. Recently, deep learning (DL) methods have brought a subversive revolution in the field of artificial intelligence (AI). This paper presents a new DL classification method based on unsupervised feature extraction and supervised fine-tuning strategy to classify the saturated and unsaturated regions in case of CT saturation. In other words, if protection system is subjected to a CT saturation, proposed method will correctly classify the different levels of saturation with a high accuracy. Traditional AI methods are mostly based on supervised learning and rely heavily on human crafted features. This paper contributes to an unsupervised feature extraction, using autoencoders and deep neural networks (DNNs) to extract features automatically without prior knowledge of optimal features. To validate the effectiveness of proposed method, a variety of simulation tests are conducted, and classification results are analyzed using standard classification metrics. Simulation results confirm that proposed method classifies the different levels of CT saturation with a remarkable accuracy and has unique feature extraction capabilities. Lastly, we provided a potential future research direction to conclude this paper.

WO 3 has been highlighted as a promising material as photochromic and photocatalytic industrial application. Even though many papers reported their interesting properties, it has been rarely reported bifunctional performances. In this study, we demonstrate the effect of Cs ions on the crystal structure of WO 3 for inducing bifunctional photocatalytic and magnetic properties. Hexagonal Cs-doped WO 3 nanoparticles were prepared via a two-step approach. Chemical coprecipitation was conducted using ammonium tungstate and Cs 2 CO 3 in acidic media. Subsequently, the nanoparticles were annealed at a low temperature under N 2 flow. The prepared WO 3 nanoparticles doped with 0.5 Cs exhibit enhanced adsorption ability and photocatalytic activity compared those doped with different amounts of Cs. The addition of Cs to WO 3 modifies the electronic structure of the material, resulting in an increased number of unpaired electrons that can be used to couple magnetic moments. The results confirm that introducing Cs dopants into WO 3 leads to bifunctional optical and electrical characteristics of WO 3 . It is expected that current work contributes bifunctional performances in an industrial application.

We investigated the feasibility of preparing nanocrystalline oxotitanium phthalocyanine (TiOPc) from crude TiOPc using liquid-phase direct recrystallization under the microwave irradiation. Different crystal structures and morphologies of TiOPc were obtained through acidtreatment and recrystallization method. The nanocrystalline TiOPcs prepared in various conditions were characterized by the means of an X-ray diffractometry (XRD), a transmission electron microscopy (TEM) and a photoconductivity measuring device.

In this study, pure BiVO4 powder and metal-doped M-BiVO4 (M = Mg, Cu) powder, well known as thermochromic materials, were prepared from a mixed aqueous solution of bismuth nitrate (Bi(NO3)3) and ammonium vanadate (NH4VO3) in autoclave by hydrothermal method. The crystal structure, microstructure, and thermochromic property of samples were analyzed using FE-SEM, FT-IR, XRD, DSC, UV-Vis-NIR spectroscopy and colorimeter. When heating samples above phase transition temperature, the color of M-BiVO4 (M = Mg, Cu) sample was thermally changed more clearly than that of using only pure BiVO4 sample.

In this study, vanadium dioxide (VO2) powder well known as a thermochromic material was prepared from V2O5 powder and oxalic acid dihydrate by hydrothermal and calcination process at various conditions. The chemical bonding and crystal structures in addition to thermal property of samples were determined using FE-SEM, XRD, XPS, and DSC. Also, spectroscopic and thermochromic properties of film samples were analyzed by UV-Vis-NIR spectroscopy after the thin film was prepared from the sol dispersed with the size of below 50 nm by the ball-milling of powder sample. With increasing the calcination temperature, the phase transition temperature of samples increased from 40 ℃ to 70 ℃ due to the increase of particle size. Keywords