The Effect of Niobium and Rubidium Doping on the Energy Band Gap of a Lithium Tantalate (LiTaO3) Thin Film

Chemical solution deposition (CSD) is a technique for making a film by keeping synthetic arrangements on the outer layer of the substrate. The outcomes show that the band gap energy of the LiTaO3 film is 1 eV. Electrons are more effectively invigorated to the valence band than to the conduction band on the grounds that the energy required is not excessively huge. Niobium-doped LiTaO3 film has a band gap energy of 1.15 eV. A large amount of energy is needed for electrons to be energized from the valence band to the conduction band. The rubidium-doped LiTaO3 film has a band gap energy of 1.30 eV.

Scalar-Torsion Theories in Four Dimensional Static Spacetimes

In this paper, we consider a class of static spacetimes scalar-torsion theories in four dimensioanal static spacetimes with the scalar potential turned on. We discover that the 2-dimensional submanifold must admit constant triplet structures, one of which is the torsion scalar. This indicates that these equations of motion can be reduced to a single highly non-linear ordinary differential equation known as the master equation. Then, we show that there are no exact solution of the scalar-torsion theory in four dimensions considering the Sinh-Gordon potential.

Einstein-Klein-Gordon System in Higher Dimensional

In this present work, we study the Einstein equation coupled with the nonlinear Klein-Gordon equation. We obtain Ricci tensor, scalar curvature, and Einstein equation of the Einstein-Klein-Gordon system in higher dimensional. If we put D=4, our formulations reduce to the four dimensional Einstein-Klein-Gordon system.

MODIFIED CORRELATION WEIGHT K-NEAREST NEIGHBOR CLASSIFIER USING TRAINING DATASET CLEANING METHOD

In pattern recognition, the k-Nearest Neighbor (kNN) algorithm is the simplest non-parametric algorithm. Due to its simplicity, the model cases and the quality of the training data itself usually influence kNN algorithm classification performance. Therefore, this article proposes a sparse correlation weight model, combined with the Training Data Set Cleaning (TDC) method by Classification Ability Ranking (CAR) called the CAR classification method based on Coefficient-Weighted kNN (CAR-CWKNN) to improve kNN classifier performance. Correlation weight in Sparse Representation (SR) has been proven can increase classification accuracy. The SR can show the 'neighborhood' structure of the data, which is why it is very suitable for classification based on the Nearest Neighbor. The Classification Ability (CA) function is applied to classify the best training sample data based on rank in the cleaning stage. The Leave One Out (LV1) concept in the CA works by cleaning data that is considered likely to have the wrong classification results from the original training data, thereby reducing the influence of the training sample data quality on the kNN classification performance. The results of experiments with four public UCI data sets related to classification problems show that the CAR-CWKNN method provides better performance in terms of accuracy.

Effect of Dimensionality on The Electronic Properties of SnSe: A Density Functional Theory Study

This study investigated the structural and electronic properties of bulk, bilayer, and monolayer SnSe using the density functional theory (DFT) method. We succeeded in calculating the bandgap and identifying accurately the transformation of the band structure from bulk to monolayer systems using generalized gradient approximation. An increase in the lattice parameter a and a decrease in the lattice parameter b were observed when the bulk dimensions were reduced to a monolayer. The reduction of van der Waals interactions when the dimensions of a system are reduced is the main factor that causes changes in lattice parameters. The indirect bandgap of bulk SnSe (0.56 eV, 0.3∆→0.7Σ) becomes wider in the monolayer system (0.94 eV, 0.2∆→0.8Σ). Bandgap widening is predicted due to the emergence of the quantum confinement effect in low-dimensional systems. Furthermore, we found the formation of a quasi-degenerate minimum conduction band in the monolayer SnSe. With the formation of these bands, we predict the monolayer SnSe will have better thermoelectric properties than the bulk or bilayer system. This study provides an in-depth understanding of the electronic structure of SnSe and its correlation to thermoelectric properties.

Lid-Driven Cavity For Mantle Convection Modelling Using Lattice Boltzmann Method

The Lattice Boltzmann Method is one of the computational fluid dynamics methods that can be applied to simulate fluid based on the microscopic and kinetic theory of gases. In this study, earth mantle convection is simulated by combining the concept of lid-driven cavity simulation and natural convection using the Lattice Boltzmann method in a two-dimensional system (D2Q9). The results of the lid-driven cavity and natural convection simulation are comparable to previous works. This study shows that at a certain lid velocity, the direction of the moving plume is changed. This earth mantle convection simulation will give better and more reliable results by considering more complicated boundary conditions and adequate simulation systems.

In-House Software Development for Data Visualization of Random Motion Configuration of Particles in Fluid

This study aims to develop in-house software for data visualization program using Python programming language. Implement a simple algorithm and use the matplotlib library for 2D plotting. The results of development of this program were tested using a dataset from random motion simulation results of many particles modeled by two-dimensional circle shape and the diameter size as D. Data visualization in the form of particles configuration then confirmed with the particles configuration of the simulation results. Based on the test, it is found that the particles configuration results of the visualization are same as the configuration of the simulated particles. This shows that the data visualization program that has been developed can be used to process other data stored in a predetermined data format.

A Modelling of Tunnelling Current through a Trapezoidal Potential Barrier by Using Exponential Wavefunction Approach

A tunnelling current through a trapezoidal barrier potential has been modelled. The transmittance is determined using the exponential wavefunction approach method. Furthermore, the transmittance is used to calculate the tunnelling current density by applying the Gauss-Laguerre quadrature method. The simulation results show the increasing bias voltage causes the raising tunnelling current, and an increase of temperature is proportional to the tunnelling current.

Review on monitoring natural and environmental radiation and its potential from mining products

Monitoring of natural radiation in Indonesia has been carried out by various parties, from researchers, academics at universities to special agencies tasked with handling this matter, such as the National Nuclear Energy Agency (Batan) and the Nuclear Energy Supervisory Agency (Bapeten). Batan through the Center for Radiation Safety and Metrology Technology (PTKMR) is in charge of monitoring natural radiation at the national level. The purpose of this paper is to review the monitoring of natural and environmental radiation in Indonesia and the potential of mining products as a source of natural radiation. The mining products that will be reviewed in this paper are natural uranium and thorium which are usually found in several mines, such as tin mines and others.

Review on monitoring natural and environmental radiation and its potential from mining products

Monitoring of natural radiation in Indonesia has been carried out by various parties, from researchers, academics at universities to special agencies tasked with handling this matter, such as the National Nuclear Energy Agency (Batan) and the Nuclear Energy Supervisory Agency (Bapeten). Batan through the Center for Radiation Safety and Metrology Technology (PTKMR) is in charge of monitoring natural radiation at the national level. The purpose of this paper is to review the monitoring of natural and environmental radiation in Indonesia and the potential of mining products as a source of natural radiation. The mining products that will be reviewed in this paper are natural uranium and thorium which are usually found in several mines, such as tin mines and others.