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A simple harmonic quantum oscillator: fractionalization and solution
Get PDFA quantum mechanical system that mimics the behavior of a classical harmonic oscillator in the quantum domain is called a simple harmonic quantum oscillator. The time-independent Schrödinger equation describes the quantum harmonic oscillator, and its eigenstates are quantized energy values that correspond to various energy levels. In this work, we first fractionalize the time-independent Schrödinger equation, and then we solve the generated problem with the use of the Adomian decomposition approach. It has been shown that fractional quantum harmonic oscillators can be handled effectively using the proposed approach, and their behavior can then be better understood. The effectiveness of the method is validated by a number of numerical comparisons
Laser cladding powder flow field detection system based on ISR optimization algorithm
Get PDFIn coaxial powder feeding laser cladding, the morphology of the powder flow field is crucial for the forming quality. Therefore, this study utilizes high-speed imaging technology and an Image Super Resolution algorithm to create a laser cladding powder flow field detection system that is capable of detecting and tracking powder particles in the laser cladding environment. The experiment shows that the optimized algorithm has significant improvement in structural similarity indicators, with an improvement rate of nearly 11 %. For powder particle tracking, the distance accuracy of the optimized model is 1.5 lower than that of the unimproved model. In addition, by combining with the Kalman filtering algorithm, the tracking effect of powder particles has been further improved. This paper also found a relationship between powder transfer rate and powder utilization rate. In summary, the powder flow field analysis based on visual detection and image processing technology designed in this study can effectively reflect and predict the trend of changes in cladding quality
Numerical simulation of the deformation behavior of a composite foundation consisting of rubber particle loess-CFG under dynamic loading
Get PDFThe CFG pile technology is primarily employed for foundation reinforcement, offering cost-saving benefits and demonstrating significant reinforcement effects. Consequently, it has gained widespread utilization. However, due to its unique composition and exceptional strength characteristics, investigating the dynamic properties of rubber particle loess-CFG poses significant challenges. In this study, a numerical simulation approach is employed to investigate the dynamic characteristics of rubber particle loess-CFG and its deformation response under dynamic loading is analyzed. The results indicate that the deformation of rubber particle loess-CFG remains minimal under static loading, while it significantly increases under dynamic loading. However, the vertical and horizontal displacements at the top of the mattress layer are comparatively smaller than those observed in loess-CFG, highlighting their seismic stability. The mattress layer of the rubber particle loess-CFG undergoes vertical compression and deformation, while being horizontally squeezed towards the central region. The horizontal displacement and its variation range are significantly greater than that of the entire pile and the soil between piles. Therefore, it is crucial to analyze the material properties, thickness, and extent of the mattress layer during design in order to mitigate its influence. When subjected to dynamic loading at the base of the model, the rubber particle loess-CFG exhibits a strip distribution of vertical displacement which gradually decreases from bottom to top. Moreover, as focal depth increases, the impact of dynamic loading on foundation deformation diminishes. Consequently, rubber particle loess-CFG provides a dual functionality of enhancing foundation strength while effectively resisting dynamic deformations. These research findings provide a theoretical basis for designing reinforced foundations using rubber particle loess-CFG and offer an innovative approach for recycling waste tire rubber particles
Mathematical modeling of piezoceramic spherical shell actuator for vibration generating devices
Get PDFThe article examines the relevance of piezoceramic spherical shell actuators, which provide a high level of accuracy and stability in the generation of vibrational oscillations over a wide range of amplitude-frequency characteristics. The spherical shape of these actuators is chosen because it allows for uniform distribution of mechanical stresses across the actuator’s surface, thereby enhancing its durability and efficiency compared to traditional flat or cylindrical designs. The study presents analytically derived mathematical models and formulas for determining the electrical impedance of piezoelectric elements and analyzes the dependence of the amplitude of electrical impedance on frequency and the charge ratio on the polarized surfaces of the spherical piezoceramic element. The proposed model enables the determination of electrical impedance as a function of cyclic frequency and various parameters (geometric, physical and mechanical, electrical) of the actuators. The study establishes that spherical shell actuators exhibit a higher quality factor (2-2.5 times greater than disk actuators and 1.4-1.8 times greater than cylindrical actuators) and a significant reduction in impedance (2.5-7 times lower) at electromechanical resonance frequencies around 2.4 kHz. Furthermore, spherical actuators demonstrate 20-30 % better resistance to deformation and 15-25 % lower susceptibility to local resonances compared to other actuator shapes, which enhances operational stability and vibration generation accuracy
Use of fibre optic systems for detection of small leaks on trunk pipelines
Get PDFThis paper is devoted to the issue of efficiency of application of fibre optic leak detection systems for identification of small leaks on trunk pipelines. The main methods of leak detection currently in use have been considered, and parametric and fibre optic LDS have been selected for comparative analysis. In the course of the research a model of product leakage from an underground oil pipeline equipped with a fibre-optic LDS was built in the COMSOL Multiphysics software package. The result of the simulation was the estimated time of leak identification by the fibre-optic system, which turned out to be much shorter than that of the parametric LDS. Compensable environmental damage for each type of system was then calculated, confirming the effectiveness of fibre optic LDS for detecting small leaks on trunk pipelines due to the significant reduction in compensable damage
Optimizing Pelton turbine performance: unveiling the power of three nozzles for maximum efficiency and sustainable hydropower generation
Get PDFWater energy is one of the potential renewable energy, the problem so far has a low efficiency of the blade Pelton shape. So it takes a series of tools to know characteristics and performance of the Pelton turbine as a hydroelectric power plant in this research. Pelton turbines work by utilizing the potential energy of water stored at a certain head, which flows through a penstock/pipe that is equipped with a nozzle at the end. The high head causes the water to be under high pressure when it reaches the nozzle. The water coming out of the nozzle becomes kinetic energy in the form of a pressurized water jet, which is used to rotate the runner of the Pelton turbine. In this study, the effect of the number of nozzles used to rotate the Pelton turbine was analyzed, with the result that the number of nozzles is directly proportional to the efficiency of the Pelton turbine. Where the highest efficiency value is obtained by using 3 nozzles with a maximum efficiency value of 13.7 %, at 2 nozzles of 12.209 % and at 1 nozzle of 8.82 %
Torsional effect analysis of high-rise reinforced concrete space grid cassette multi-tube structure system
Get PDFThe manuscript introduces a new structural system called the reinforced concrete (RC) space grid cassette multi-tube structure for high-rise buildings. A case study building is analyzed using this system and compared to a conventional RC frame-core tube structure. Through modal analysis in the software “Midas Gen”, the torsional effect and control indices like inter-story displacement ratio, maximum displacement, etc. are compared between the two structural systems. The results show that the space grid cassette system has smaller displacement ratios, displacements, inter-story torsion angles, and thus better torsional resistance compared to the conventional frame-core tube system. Based on these analyses, the manuscript concludes that the RC space grid cassette multi-tube structural system has superior seismic performance and is more suitable for irregularly shaped high-rise residential buildings
Prevalence of child malocclusion and its association with time of breastfeeding and/or deleterial habits in children from 2 to 6 years old at public schools in Bento Gonçalves, Rio Grande do Sul, Brazil – pilot project
Get PDFKnowing that the worldwide prevalence of malocclusion in early childhood is 54 %, we carried out a pilot project in the first half of 2022 at Public Schools in Bento Gonçalves RS, evaluating 1938 children between 2 and 6 years old. The prevalence of malocclusion found was 23 %. Anterior open bite, whether or not accompanied by posterior crossbite, was the most prevalent malocclusion. About 70 % of the children were not breastfed or breastfed for less than 6 months, presenting a non-nutritive sucking habit. Assessing 5 years old children alone, this prevalence rose to 54 %. The results reinforce the need of public health policies that promote and support prolonged breastfeeding, which expand the knowledge of parents or guardians and school staff about the adverse effects caused by the use of pacifiers and baby bottles, with the adoption of transdisciplinary measures for the prevention, interception and treatment of malocclusions in a timely manner
Maintenance decision-making and its relevance in engineering asset management
Get PDFEngineering asset management (EAM) has received a lot of attention in the last few decades. Despite this, industries struggle to identify the best strategies for maintaining assets. The decision-making around selecting a relevant maintenance strategy generally considers factors like risk, performance and cost. Risk management is, usually, largely subjective and industries consequently make investments in a subjective manner, making the allocation of budget unstructured and arbitrary. Generally, industries focus only on either overt risks or basic performance of assets, thus creating uncertainties in the decision-making process. Recently, however, maintenance decision-making has evolved from a subjective assessment, chiefly dependent on expert opinions, to utilizing live-data-sensor technology. The attitude towards component failures and how to address them has changed drastically with the evolution of maintenance strategies. Additionally, the emergence and use of several tools and models have assisted the drafting and implementation of effective maintenance strategies. These advancements, however, have only considered discrete parameters while modelling, instead of using an integrated approach. One of the primary factors which can address this shortfall and make the decision-making process more robust is the economic element. To enable an effective decision-making process, it is imperative to consider quantifiable determinants and include economic parameters while drafting maintenance policies. This paper reviews maintenance decision-making strategies in EAM and also highlights its relevance through an economic lens
A special graph for the connected metric dimension of graphs
Get PDFGiven a connected graph G=(V, E), let d(x, y) represent the separation between x and y at its vertices. If each vertex in a collection B is uniquely identified by its vector of distances to the vertices in B, then that set of vertices resolves a graph G. A metric dimension of G is represented by dim(G) and is the smallest cardinality of a resolving set of G. If the subgraph B- induced by B is a nontrivial connected subgraph of G, then a resolving set B of G is connected. The metric dimension of G is the cardinality of the minimal resolving set, while the connected metric dimension of G is the cardinality of the smallest connected resolving set. The connected metric dimension of the knots graph, whitehead link graph and jewel graph are determined in this study. Finally, we derive the explicit formulas for the triangular book graph, quadrilateral book graph and crystal planar map