43 research outputs found
Stability Analysis of the Inhomogeneous Perturbed Einstein Universe in Energy–Momentum Squared Gravity
No full textThe main objective of this article is to examine the stability of Einstein static universe using inhomogeneous perturbations in the context of energy–momentum squared gravity. For this purpose, we used FRW spacetime with perfect matter distribution and formulated static as well as perturbed field equations. We took a minimal model of this theory to investigate the stable regions of the Einstein universe for conserved and non-conserved energy–momentum tensors. We found that stable modes of the Einstein universe appeared in both conserved and non-conserved cases for all values of the equation of state and model parameters corresponding to both open and closed cosmic models. We found that stable solutions in this modified theory were obtained for a broader ω-region compared to other modified theories
Traversable Wormhole Solutions Admitting Noether Symmetry in f(R,T2) Theory
No full textThis paper uses the Noether symmetry approach to examine the viable and stable traversable wormhole solutions in the framework of the f(R,T2) theory, where R is the Ricci scalar and T2=TμνTμν is the self-contraction of the stress–energy tensor. For this purpose, we consider a specific model of this modified theory to obtain the exact solutions of the Noether equations. Further, we formulate the generators of the Noether symmetry and first integrals of motion. We analyze the presence of viable and stable traversable wormhole solutions corresponding to different redshift functions. In order to determine whether this theory provides physically viable and stable wormhole geometry or not, we check the graphical behavior of the null energy constraint, causality condition and adiabatic index for an effective stress–energy tensor. It is found that viable and stable traversable wormhole solutions exist in this modified theory
Analysis of Cosmic Evolution admitting Garcia-Salcedo Ghost and Generalized Ghost Dark Energy Models
No full textThis study aims to explore the Garcia-Salcedo ghost dark energy and
generalized ghost dark energy models in the context of
theory, where is the Ricci scalar and
is the self-contraction of stress-energy tensor. We investigate
the non-interacting case only corresponding to flat Friedmann-Robertson-Walker
universe. We reconstruct the corresponding gravity
models using the considered dark energy models by taking two particular models
of this gravity. The stability analysis is performed for all the cases. The
behavior of the equation of state parameter is also checked. It is found that
some of the reconstructed models successfully
describe both the phantom and quintessence epochs of the universe, which
support the current cosmic accelerated expansion. This exploration reveals the
intricate connections between dark energy models and modified gravitational
theory, providing significant understanding into the dynamics of the cosmos on
a large scale.Comment: 26 pages, 11 figures, Accepte
Development and characterization of acoustic energy harvesters for low power wireless sensor network
No full textWireless Sensor Nodes (WSNs) have developed significantly over the years and have a significant potential in diverse applications in the fields of science and technology. The inadequate energy accompanying with WSNs is a key constraint of WSN skills. To overwhelm this main restraint, the development and expansion of effective and reliable energy harvesting systems for WSN atmospheres are being discovered. In this research, low power acoustic affordable and clean energy harvesters are designed and developed by applying different techniques of energy transduction from the sound available in the surroundings. Three acoustic energy harvesters were developed based on piezoelectric phenomenon, electromagnetic transduction & Hybrid respectively. The CAD modelling, lumped modelling and Finite Element Analysis of the harvesters were carried out. The voltages were obtained using FEA for each Acoustic Harvester. Characterization of all the three harvesters were carried out and the power generated by piezoelectric harvester, electromagnetic harvester and Hybrid Acoustic Energy harvester are 2.25x10-9W, 0.0533W and 0.0232W respectively
Viable and stable compact stars in
No full textIn this paper, we study the viability and stability of anisotropic compact stars in the context of theory, where is non-metricity scalar. We use Finch–Skea solutions to investigate the physical properties of compact stars. To determine the values of unknown constants, we match internal spacetime with the exterior region at the boundary surface. Furthermore, we study the various physical quantities, including effective matter variables, energy conditions and equation of state parameters inside the considered compact stars. The equilibrium and stability states of the proposed compact stars are examined through the Tolman–Oppenheimer–Volkoff equation, causality condition, Herrera cracking approach and adiabatic index, respectively. It is found that viable and stable compact stars exist in theory as all the necessary conditions are satisfied
Genome-Wide Identification of Stress-Associated Proteins (SAPs) Encoding A20/AN1 Zinc Finger in Almond (<i>Prunus dulcis</i>) and Their Differential Expression during Fruit Development
No full textStress-associated proteins (SAPs) are zinc finger proteins involved in the regulation of various stresses in a variety of plant species. A total of nine PdSAP genes were identified in Prunus dulcis. Phylogenetic and synteny analyses were performed to analyze the homology and evolutionary relationship of PdSAP genes. The functions of PdSAP genes were assessed by further analyses, including cis-regulatory elements, gene duplication, gene ontology, gene structure, subcellular localization, and motif pattern. This study found that PdSAP genes were unevenly distributed on chromosomes 2, 3, 6, and 7. Phylogenetic analysis of PdSAP genes with Arabidopsis thaliana and Oryza sativa suggested that six subgroups have a similar pattern of AN1 and A20 domains in each subgroup. PdSAP genes lacked duplicated blocks. The majority of PdSAP genes were localized in the nucleus region. Three hormonal and five stress cis-regulatory elements were found in the upstream promoter region of the PdSAP gene family. RNA-seq analysis revealed differential gene expression of PdSAP genes at days 12, 17, 22, 27, 32, and 37 of fruitlet development after flowering. This study identifies the SAP genes in P. dulcis and also provides insights into the expression of PdSAP genes in abnormal fruitlets with diapause atrophic growth at various developmental stages
Motion Synchronization Control for a Large Civil Aircraft’s Hybrid Actuation System Using Fuzzy Logic-Based Control Techniques
No full textThe motion synchronization of the hybrid actuation system (composed of a servo-hydraulic actuator and an electro-mechanical actuator) is very important for all applications, especially for civil aircraft. The current research presents a nested-loop control design technique to synchronize motion between two different actuators, such as a servo-hydraulic actuator (SHA) and an electro-mechanical actuator (EMA). The proposed strategy consists of a trajectory, an intelligent position controller (fuzzy logic-based controller), a feed-forward controller, and an intelligent force controller (fuzzy logic-based controller). Position, speed, and acceleration signals are produced by trajectory at a frequency that both SHA and EMA can follow. The SHA/EMA system’s position tracking performance is enhanced by the feed-forward controller and intelligent position controller working together, while the intelligent force tracking controller lowers the issue of force fighting by focusing on the rigid coupling effect. To verify the effectiveness of the proposed strategy, simulations are performed in the Matlab/Simulink environment. The result shows that the proposed intelligent control strategy not only reduces initial force fighting, but also improves load-rejection performance and output-trajectory tracking performance
Business intelligence as a knowledge management tool in providing financial consultancy services
No full textThe main objective of this paper is to elaborate how Business Intelligence (BI) as a knowledge management tool could help consultants in providing professional services to the financial sector. The Business Intelligence (BI) solution could be a competitive advantage for the consultants if they are able to exploit the Business Intelligence (BI) tools and technology such as Data Warehouse, Data Mining, On-Line Analytical Processing (OLAP) and Extraction Transformation Load (ETL). The consultants can use Business Intelligence (BI) solution to analyze the organizational data such as structures and business processes of the Financial Institution. By analyzing the organizational data, the financial institution can imp better rove and streamline functional efficiencies to not only bolster up sales and marketing strategies and better develop customer services program, but also mitigate risk by developing more appropriate risk management actions. In brief, by having this competitive advantage, the consultant will be able to withstand in the market, which is always changing
Mechanical Properties of Plastic Concrete Made Using Recycled Aggregates for Paving Blocks
No full textInternational audienceIn developing countries, the management of waste continues to be a major challenge, especially in urban areas. One of the major concerns for today’s world is the management of plastic and construction and demolition (C&D) wastes which are increasing with urbanization and population growth. This study aims to explore the possibility of the use of plastic waste as a binder and recycled aggregates obtained from C&D waste to produce concrete paving blocks. The mechanical investigation was carried out to find the optimum content of plastic waste to prepare the plastic concrete. Three different concrete mixes were prepared with plastic contents of 30%, 40%, and 50% by the weight of aggregate. To evaluate the mechanical properties of plastic concrete, compression, flexural, and ultrasonic pulse velocity (UPV) tests were performed on the prepared samples. Cubical specimens of 36 x 40 x 40 mm for compression tests and prismatic specimens of 36 x 40 x 120 mm for flexural tests were cut using a saw from the paving blocks of size 36 x 137 x 290 mm. The results indicated that the strength of plastic concrete increased with the increase in plastic content. The maximum compressive and flexural strength was achieved at 50% plastic content, which was 40.52 MPa and 10.13 MPa, respectively. The compressive and flexural strengths of plastic concrete were compared with the minimum strength requirement specified by various standards specification such as American, Canadian, and Chinese. It was found that plastic concrete with 50% content of plastic waste meets the minimum criteria of mechanical strengths specified in these standards. Presently, many countries of the African continent are facing severe problems of plastic waste. As per the findings of this study, the use of waste plastics in molten form as the only binder in the development of concrete paving blocks could offer a solution for such countries to beneficially manage the plastic waste
