Journal of Computational and Theoretical Nanoscience
Journal Information
ISSN / EISSN: 15461955 / 15461963
Published by:
American Scientific Publishers
Total articles ≅ 8,407
Latest articles in this journal
Published: 1 June 2021
Journal of Computational and Theoretical Nanoscience, Volume 18, pp 1737-1743; https://doi.org/10.1166/jctn.2021.9608
Abstract:
VR 360 Cam is an emerging device. By combining this with the rising webtoon industry, we want to show people an immersive webtoon. Based on the python language, face detection was performed from images received in real time from VR 360 Cam through dlib, a machine learning library that supports python. The VR 360 Cam performs trekking on the detected face to receive each detected position value, and is converted into a natural face through rectification to be shown to the audience. The exhibition, which performed face detection from the VR 360 Cam, and showed the image of the person’s face mapped to the audience, drew meaningful results. Unlike cameras such as webcams, VR 360 Cam has a wider viewing angle, allowing more people to interact. Existing webcams can only interact with one person at a time because it is impossible to interact with more people due to a narrow angle when one person enters. On the other hand, interaction with multiple people is possible through VR 360 Cam. Various exhibitions were possible.
Published: 1 June 2021
Journal of Computational and Theoretical Nanoscience, Volume 18, pp 1692-1701; https://doi.org/10.1166/jctn.2021.9722
Abstract:
This work presents an analytical study of electronic transport in dimerized trans-polyacetylene (Trans PA) oligomers containing even (n = 4, 6, 8, 10 sites) and odd (n = 3, 5, 7, 9 sites) chains where the site C1 is sandwiched by two metallic electrodes (Left and Right). These devices exhibit T-shaped geometry and are investigated by Su-Schrieffer-Heeger (SSH) model via Heisenberg equation of motion combined with the Keldysh formalism. We introduced disorder into the system through the dimerization force (δ) demonstrating that the dimerization in the chain can effectively lead to a linear (low δ) or zigzag (high δ) behavior, besides also suffering increase or decrease in conductance peak [dI/dV]max. The odd chains exhibit trivial topological behavior to which the conductance peaks are suppressed as dimerization disorder is considered-creates barriers for tunneling. On the other hand, we have an opposite behavior for conductance peaks in the even chains. For example, the chain with weak dimerization (low δ) has a perfect transmission for even chains. In addition, we note for odd chains the formation of a plateau in the I–V curve for bias voltages and for even chains that show a linear current. This procedure shows an analytical study through the tunneling of the parameters on the device, such parameters as the tunneling amplitude (ГL/R) can be accessible experimentally.
Published: 1 June 2021
Journal of Computational and Theoretical Nanoscience, Volume 18, pp 1685-1691; https://doi.org/10.1166/jctn.2021.9730
Abstract:
In this article we examine the weighted average finite difference methods to approximate the fractional variable-order wave equation, where, the order of the differentiation can be a function of time. The fractional differentiation of the of variable-order are described in terms of the Riemann-Liouville concept. The stability of the utilized method are proved by using a kind of Von Neumann analysis. To reveals that the method is effective, two examples are offered. and the obtained solutions were compared with the exact solutions.
Published: 1 June 2021
Journal of Computational and Theoretical Nanoscience, Volume 18, pp 1724-1729; https://doi.org/10.1166/jctn.2021.9724
Abstract:
In this manuscript, we discuss a new weighted distribution, which called the volume–biased Rayleigh (VB-R) distribution. The VB-R model is more flexible than some well known models and it has many applications in physics and medicine. The statistical properties of the VB-R distribution as; moments, mean, variance, moment generating function, incomplete moments, inequality measures, order statistics and Rényi an q entropies are calculated. The maximum likelihood (ML) estimators for the unknown parameter of the volume-biased Rayleigh distribution, based on complete samples. Finally, applications on real data-sets are provided to determine whether the VB-R distribution is better than other well-known distributions in modeling lifetime data or not.
Published: 1 June 2021
Journal of Computational and Theoretical Nanoscience, Volume 18, pp 1754-1758; https://doi.org/10.1166/jctn.2021.9727
Abstract:
The fading phenomenon in mobile communications is mainly a stochastic process and plays an essential role in the reliability and stability of the systems. The frequency bands currently in use it is reasonably well characterized and described. With the use of mmW, only experimental, theoretical models are being proposed; there is no unanimity regarding a model that effectively contemplates the phenomenon in this spectrum range. Some studies suggest the traditional models applied to the frequencies in use; Rician and Rayleigh are the main ones. This study aims to advance and compare, with accepted models, a broader statistical model that overcomes the limitations of the current models. It will be analyzed and compared a model using the Nakagami-m distribution covering a greater range of possibilities, given the low spreading capacity of mmW and the need for links almost always LOS situation in which the Rician model fails.
Published: 1 June 2021
Journal of Computational and Theoretical Nanoscience, Volume 18, pp 1714-1723; https://doi.org/10.1166/jctn.2021.9729
Abstract:
This work presents an investigation on the electronic transport of two devices based on Zigzag Phagraphene Nanoribbons of different widths (ZPGNR1 and ZPGNR2) with Nitrogen-doped edge terminations based on DFT-NEGF methodology using TranSIESTA code. Our results show different transport regimes: (i) ZPGNR1 device exhibits metallic behavior and metal-semiconductor transition when the bias voltage is increased, with symmetry on the eigenchannels (ECs) and the field-effect transistor (FET) signature; and (ii) ZPGNR2 device presents topological insulator (TI) behavior and two operation windows, the first with FET signature characterized by the TI-semiconductor transition and the second with resonant tunnel diode (RTD) signature with broken ECs symmetry due to potential barrier caused by N-doping at the edge and the central region is preferential transport path for the device, inherent to TI systems, generating a negative differential resistance (NDR). Another alternative for ZPGNR2 is to consider a current limiter device Molecular Positive Electronic Transition (MPET)-like.
Published: 1 June 2021
Journal of Computational and Theoretical Nanoscience, Volume 18, pp 1737-1743; https://doi.org/10.1166/jctn.2021.9728
Abstract:
The structured environment requires an appropriate solution to reactive power management. During the restructuring of the electricity industry, power systems were divided into three main parts: generation, transmission, and distribution companies, coordinated by an independent system operator. Active power is the most important commodity traded in the electricity market. The independent operator of the grid has the duty of providing the necessary conditions for the realization of energy contracts on the transmission grid at any time. The arrangements that are considered for the production and delivery of energy to the consumer are called ancillary services. Among the various ancillary services required in a competitive market, reactive power services to control the bus voltage are among the most important services provided by the system operator. Lack of reactive power in the grid is one of the factors that limit the fulfillment of energy contracts and can even endanger the security and voltage stability in the grid. In references, by assuming the results of the active power market is constant, the optimal load of reactive power is distributed. This model always entitles the generator to receive cost for the reactive power needed to stabilize its active energy.
Published: 1 June 2021
Journal of Computational and Theoretical Nanoscience, Volume 18, pp 1730-1736; https://doi.org/10.1166/jctn.2021.9721
Abstract:
Estimation methods to handle missing data problems in various panel data models are rarely discussed. However in the panel vector autoregressive model, there is no estimator to handling this type of problems. The traditional treatment for cases of involving incomplete data is to use generalized method of moment estimation based only on the available data without imputation the missing data. Thus, this study introduces a generalized method of moment estimator for the panel vector autoregressive model for solving problems involving incomplete dataset. Our proposed estimator is based on mean imputation with generalized method of moment estimation to achieve more efficiency. The statistical properties of the proposed estimator are presented. Additionally, real data application is used to investigate the efficiency of the proposed estimator compared with the traditional generalized method of moment estimator. The results showed that the proposed estimator is better than the traditional generalized method of moment estimator, even if the percentage of missing data is up to 40%.
Published: 1 June 2021
Journal of Computational and Theoretical Nanoscience, Volume 18, pp 1667-1676; https://doi.org/10.1166/jctn.2021.9731
Abstract:
The present investigation studies the Jeffery fluid model’s peristaltic flow by means of an asymmetric channel. Mathematical analysis has been performed on the exitance of a magnetic field, as well as the mass and heat transfer associated with an asymmetric channel with peristaltic flow. The mass and heat transfer’s impact, a magnetic field, and concentration on blood peristaltic flow associated with an asymmetric channel is investigated in this study. A mathematical assay took place in the a magnetic field’s exitance, examining the flow in a wavy frame of references traversing with the wave’s velocity. The physical problem is illustrated with the first model; the analytical solution is carried out with a low-Reynolds and long-wavelength number assumption. Accurate values of the heat transfer coefficient and equations for the following variables were found. The numerical results were illustrated graphically for the sake of different values of interest in terms of physical parameters. Plotting graphs based on computational results allows for examination of the impacts of pertinent features on the abovementioned volumes and quentities. The findings show that parameters have a significant impact.
Published: 1 June 2021
Journal of Computational and Theoretical Nanoscience, Volume 18, pp 1744-1753; https://doi.org/10.1166/jctn.2021.9733
Abstract:
In this paper, a new distribution with three parameters named Discrete Type II Topp Leone inverted Weibull (DTIITLIW) distribution is derived using the Type II Topp Leone family and the general approach of discretization of a distribution. Some of the statistical properties are obtained for the new distribution. Different estimation procedures are used to estimate the model parameters; moments and maximum likelihood methods. The importance and flexibility of the new distribution DTIITLIW is assessed using a real data set.