Asian Journal of Research and Reviews in Physics
EISSN : 2582-5992
Published by: Sciencedomain International (10.9734)
Total articles ≅ 114
Latest articles in this journal
Published: 17 October 2022
Asian Journal of Research and Reviews in Physics pp 7-24; https://doi.org/10.9734/ajr2p/2022/v6i3118
Aims: To carried out performance analysis of a shunt active power filter (SAPF) for harmonics mitigation. Study Design: Experimental design through simulation studies using P-Q Theory and proportional integral controller. Place and Duration of Study: Department of Physics, Nasarawa State University Keffi, main campus, Nigeria, between October 2020 and September 2021. Methodology: Primary and secondary data were obtained using AVO Digital Multimeter and manufacturers’ datasheets from Schneider electric website to capture required system parameters, SAPF was designed using a Voltage Source Inverter model to represent the Three-Phase source, and P-Q Theory with PI Control was used for reference current extraction. The SAPF was modeled, designed and simulated using MATLAB-Simulink and analyzed under different nonlinear load conditions and harmonic spectrum to achieve low Total Harmonic Distortion (THD). Results: The THD in the unbalanced system voltages before the application of SAPF was found to be 12.6%, 11.4% and 11.2%, while after the application of SAPF was 2.2%, 2.5% and 2.5% for phase voltages a, b and c respectively. The grid currents indicated THD of 27.2%, 30.9% and 31% before application of SAPF and 2.2%, 2.2% and 2.1% after application. Conclusion: The use of non-linear loads; has adverse effects on the quality of electric power as well as phase voltage and frequency waveforms. The use of SAPF is of vital importance in improving electric power quality for reliable power supply and quality service delivery.
Published: 17 October 2022
Asian Journal of Research and Reviews in Physics pp 25-32; https://doi.org/10.9734/ajr2p/2022/v6i3119
In this article, the plane wave solution for a free particle in three dimensions is considered and the wave function is normalized in an arbitrarily large but finite cube. The momentum space wave function is obtained by taking the Fourier transform of the coordinate space wave function. The probability densities are employed to compute the numerical values of the information theoretic quantities such as Shannon information entropy (S), Fisher information entropy (I), Shannon power (J) and the Fisher–Shannon product (P) both in coordinate and momentum spaces for different values of the length (L) of the cubical box. Numerical values so found satisfy the Beckner, Bialynicki-Birula and Myceilski (BBM) inequality relation; Stam-Cramer-Rao inequalities (better known as the Fisher based uncertainty relation) and Fisher-Shannon product relation. This establishes the validity of the information theoretic inequalities in respect of the motion of a free particle.
Published: 14 October 2022
Asian Journal of Research and Reviews in Physics pp 1-6; https://doi.org/10.9734/ajr2p/2022/v6i3117
Background: Atomic physics and nuclear matter physics are often exclusively studied. However, atomic properties are a direct function of nuclear properties. Establishing a mathematical relationship between nuclear and atomic properties could serve the interest of nuclear and atomic engineers. Nuclear - and atomic-based instrumentation engineering and nuclear medicine (and perhaps atomic medicine) applications could be the benefits. Objectives: The research is undertaken to 1) link nuclear property, the mass-radius of the nucleon, and ionization energy of hydrogen via the derivation of appropriate equation and 2) determine the mass-radii of the nucleons and some leptons. Methods: Theoretical and computational methods. Results and Discussion: As applicable to the previous results in the literature, the larger the mass of the elementary particles, the longer the radii. For the particles investigated, the order of the radius is muon (m-)<proton (p+)< neutron (n)< tauon (t-) corresponding to increasing mass, m-<p+< n<t-. The values of the mass radii were respectively » 0.1240, 1.1012, 1.1027, and 2.0855 fm. Conclusion: Nuclear properties such as the radius of any nucleon (ΓN) can be mathematically linked to atomic properties such as the ionization energy of hydrogen via equation which shows that ΓN is inversely proportional to the ionization energy of hydrogen and directly proportional to the rest-mass of the particle.
Published: 1 October 2022
Asian Journal of Research and Reviews in Physics pp 50-58; https://doi.org/10.9734/ajr2p/2022/v6i2116
The criterion of modulational instability of the second order bright solitary wave is studied in this article. The Principle consists initially in seeking all solitary wave solutions of the bright type which verify the nonlinear partial differential equation which governs the dynamics of propagation in flattened optical fibers. When the reference solution to be subjected to a disturbance is identified, the next step consists in establishing the condition of modulational stability/instability.
Published: 19 July 2022
Asian Journal of Research and Reviews in Physics pp 41-49; https://doi.org/10.9734/ajr2p/2022/v6i230182
At low temperatures, uniaxial perovskites exhibit a spontaneous polarization with a permanent dipole moment. The broken symmetry state involves an order parameter and dielectric properties of the materials which are strongly dominated by a one-dimensional physics. For the last sixty years there has been growing interest in these crystals for potential applications in communication technology. Very recently, renewed interest to ferroelectric memory devices has been remarkable with particular emphasis on miniaturized devices. This new perspective comes along with great challenges, one of which is the critical size for stable domains in thin ferroelectric crystals. Since the polarization switching involves a pre-existing spontaneous polarization, it is of fundamental importance to address the question of conditions under which polarized domains can develop in a ferroelectric thin film. From previous articles, it has been observed that most studies focus on numerical simulations which is a good approach but for the fact that numerical simulations involve approximation of physical quantities, which is limitation to comparing experimental with theoretical studies. This motivated the authors to look purely at an analytical approach taking advantage of the new mathematical approach in the study of nonlinear systems. In this work, the authors have considered the question from an analytical point of view, focusing on an interesting model introduced by Lu and Cao. We propose an analytical counterpart of the numerical simulations done in this previous study.
Published: 15 July 2022
Asian Journal of Research and Reviews in Physics pp 25-40; https://doi.org/10.9734/ajr2p/2022/v6i230181
String theory always comes with heavy mathematical rigor as it questions the most significant and impossible attempt to make a scale-invariant phenomenology between general relativity and quantum theory. Thus, steps have been taken to simplify the theory a bit thereby making it accessible to general yet enthusiastic readers of physics. However, as there is numerous mathematics involved in the modeling of this theory, thus, any chance to make a purely non-mathematical approach towards strings would prove vacuous and intimidating making the pathway of this marvelous theory chocked with unnecessary assumptions resulting in false analogies (or hopes) relating to this theory. Thus, where it’s almost impossible to proceed without any equations, we have given a few just to wipe out some logical confusion arising to the first readers of strings. Few necessary diagrams are included along with intense theory and least mathematics for making this significant approach of theoretical physicists accessible to general learners or readers. Topics: Bosonic string theory, supersymmetric string theory, M – theory, F – theory, dualities and interconnectedness, viability, Randall – Sundrum model for tackling the hierarchy problem of particle physics, conifold singularities, Branes, Bulks, Extremal black holes, Ekpyrotic cosmology, topological aspects of Calabi – Yau (CY) manifolds, A and B models, Mirror Symmetries; AdS/CFT, cosmic strings, all in a way accessible to every reader. Methods: Theoretical analogies, deductions, principles behind the origin, development along with the probable conclusion of this theory, the roots of its origin, the necessary difficulty for detecting those strings, and approaches done by theorists to work out the pathway of achieving Einstein’s dream of unification irrespective of several hindrances. Results: String theory itself is not a complete theory. Rather it’s in the process of further development through the increment of time resulting in more applications of mathematics by developing or incorporating them in due needs. Thus, without stating any concrete results, the theory has been tackled in this paper with a viable hypothesis based on the current understanding, and previous attempts are stated to have been made for its success.
Published: 8 July 2022
Asian Journal of Research and Reviews in Physics pp 16-24; https://doi.org/10.9734/ajr2p/2022/v6i230180
The purpose of the study was to investigate students’ perception of their physics teachers’ classroom practices. The study was conducted in eight (8) senior high schools in the Hohoe Municipality in the Volta Region of Ghana. Descriptive cross-sectional survey design was employed in carrying out the study. A total sample of 200 senior high school physics students were involved in the study. A questionnaire consisting mainly of closed ended items was used in collecting data from respondents. Data collected was analysed using frequencies, percentages, mean and standard deviation. It was found that physics teachers do not often motivate students and make them appreciate the fact that the things they learn in physics are important. Based on the findings, it was recommended that physics teachers make learning of physics interesting by making students appreciate the importance of what they teach, often encourage students to study physics and also show interest in the overall success of their students.
Published: 17 June 2022
Asian Journal of Research and Reviews in Physics pp 1-15; https://doi.org/10.9734/ajr2p/2022/v6i230179
In this work, data extracted from OPAC 4.0 was compared and validated with 11 years data record from MEERA-2 model (average Angstrom Exponent and average Extinction Coefficient). The 11 years MEERA-2 model data for 10 selected deserts was extracted at an average relative humidity (RH) condition of 78%RH while OPAC considers eight different (RH) levels (00% to 99%RH). Based on the investigation, MEERA-2 model has the highest angstrom exponent (a) values for (Arabian, Danakil, Ferlo, Lompoul, Patagonian, Registan and Syrian deserts), which is greater than 1, and this signifies the dominance of fine mode particles over coarse mode particles when compared to OPAC 4.0. It can be seen that Chalbi (0.845), Karoo (0.482) and Sahara (0.417) deserts have an a values which is less than 1(indicating the dominance of coarse mode particles over fine mode particles). It can also be said that, MEERA-2 (a) is still greater than that of OPAC and this shows that the deserts atmosphere can be dominated by fine mode particles. The angstrom exponent (a) for OPAC 4.0 fluctuate all through the four studied components except for WASO which increases with the increase in RH and particles concentration (and this signifies that the particles dissolved as they uptake water and reach their saturation level). Based on the results of the investigation (time series analysis), it was found that the model’s significance (b) level are very high, and this shows that the aerosols distribution fluctuates around a reasonable stable, which signifies that the models are very significant. The analysis further found that, the significance (d) from the seasonal aspect is very poor except for Ferlo and Lompoul deserts, this signifies that season effect is consistent over time. It was also found that, the MEERA-2 has the highest visibility (km) over (OPAC 4.0). The investigation further revealed that the Arabian, Syrian and Patagonian deserts have the highest visibility (km) in the months of January, February, June, November and December. OPAC model underestimated the visibility when compared to MEERA-2 model.
Published: 20 April 2022
Asian Journal of Research and Reviews in Physics pp 39-56; https://doi.org/10.9734/ajr2p/2022/v6i130177
We tackle the issue of the factorial growth in the amplitudes of multi-Higgs production at high energy by developing a phenomenological approach based on the Higgs splitting functions and Sudakov factors. We utilize the method of generating functionals to define several jet observables for the Higgs sector. Our results suggest that pure Higgs splittings should retain a good Ultraviolet (UV) behavior in contrast to the common picture represented by the breakdown of perturbation theory and the violation of unitarity due to the high multiplicity of particles produced at or near threshold, which is found in scalar theories. We thus argue that the issue of the factorial growth in the amplitude of multi-Higgs production is probably associated with applying perturbation theory in a regime where it is no longer valid and with the n\(\lambda\) \(\to\) \(\infty\) limit, as opposed to being a sign of new physics.
Published: 19 April 2022
Asian Journal of Research and Reviews in Physics pp 31-38; https://doi.org/10.9734/ajr2p/2022/v6i130176
Using IBM-2 configuration mixing calculations, the normal and intruder 2p-2h bands in even-even tin isotopes are examined. The states of the normal and intruder bands were computed separately and then mixed using a basic band-mixing Hamiltonian. The experimental data for energy levels and electronic transition probability from current and past investigations are compared.