Concept Of Mechanism Research Articles

Quantum mechanics concepts for high school by means of a board game

O presente artigo traz um relato de experiência da aplicação de um produto educacional desenvolvido no programa de Mestrado Nacional Profissional em Ensino de Física. O objetivo deste trabalho foi avaliar a efetividade da utilização, no contexto da Educação Básica, do produto educacional, cujo elemento central é um jogo de tabuleiro. Intitulado Mundo Quântico, ele aborda conceitos introdutórios de Mecânica Quântica. Tanto a construção como a aplicação do produto e posterior análise de resultados foi baseada na Teoria dos Campos Conceituais de Gèrard Vergnaud. A partir da sua aplicação, foi possível constatar que a utilização do jogo nas aulas despertou o interesse dos estudantes em participar das atividades. Observou-se ainda que alguns estudantes mostraram compreender os conceitos quânticos apresentados no jogo, um indício da ocorrência de aprendizagem. Os resultados obtidos neste trabalho podem vir a contribuir para o desenvolvimento de futuras pesquisas que consistam na utilização de jogos no ensino de Física. Palavras-chave: ensino; mecânica quântica; jogo de tabuleiro.

Thermo-convection driven Sodium Alginate-based Darcy–Forchheimer EMHD Williamson hybrid nanofluid flow with varying thermal distribution

A computational investigation is furnished to explore the responses of a Darcy–Forchheimer EMHD Williamson flow of a Sodium Alginate [Formula: see text]-based Ag-Al2O3 hybrid nanofluid passing over a vertically exponentially stretching cylinder emerged through a porous region. The prime focus of this research is to encompass the inclusion of nonlinear variations in heat distribution, Newtonian boundary heating (NBH) effects, and the influence of thermo-convection alongside suction effects. Key parameters, including thermal buoyancy, Darcy porous medium effects, heat source/sink effects, Biot number, variable thermal index, and thermal convection factor, are comprehensively analyzed as these combining factors can play a crucial role in optimizing the efficacy of several systems such as heat exchanger, material processing and geothermal system that involve the concept of thermo-transportation mechanism. The physical flow dynamics are modeled, employing suitable similarity transformations, and subsequently translated into a dimensionless form. The ensuing collection of modified nonlinear ordinary differential equations is solved by employing the Bvp4c solver bundled into the MATLAB program. Several parameters are scrutinized through graphical presentations to elucidate their impacts on the velocity curve, temperature curve, skin friction coefficient, and Nusselt index. It is worth mentioning that the heat distribution profile significantly escalated for the rising values of several factors such as electric field parameter, varying thermal index, Biot number and shape factor, but the reverse is the pattern with suction and thermo-convection effect. Also, the thermal transportation rate at the proximity of the vertical cylindrical wall appears to exhibit an increment of about an average of 47% in SA-based Williamson hybrid nanofluid compared to Williamson fluid for thermo-convective effect, NBH, and thermal buoyancy. Furthermore, the proximate shear stress rate appears to be amplified by approximately 39% in Williamson hybrid nanofluid when contrasted with Williamson fluid for electric field parameter and thermo-convection effect alongside the raised Darcy–Forchheimer factor.

Valence band XPS spectra of K silicate glasses: Effect of HOMO energies on K, Na and Li leach rates, activation energies and reaction mechanism

X-ray Photoelectron spectra of K-silicate glass valence bands (VBs) are composed of distinct upper and lower bands, separated by a minimum at ∼10 eV binding energy. A third, narrow band at ∼4.5 eV represents the highest energy occupied molecular orbitals (HOMOs). Na and Li glass VBs are similarly composed of upper, lower and HOMOs bands. The HOMOs reside only on NBO atoms (NBO = O atoms of the Si-O-M moiety; M = alkali), are non-bonding orbitals of O 2py character and are located at 4.5, 4.8 and 5.2 eV in K, Na and Li glasses. The order corresponds to alkali leach rates in water. We propose a SN reaction mechanism and Frontier Molecular Orbital concepts for leaching involving the HOMOs of the glasses and the LUMO of an adsorbed water molecule. The activated complex, Si-NBO*-M (NBO* = NBO•••HO-H), is formed through H-bonding of a solvent H2O molecule to NBO.

Design & Development of Smart Fire Safety System For e-Vehicles Using IOT

The project concept of An autonomous fire safety mechanism for EVs is an inventive way of considering a less cost-effective design and a more convenient application for e-vehicle safety. Day by day, the number of fatalities in electric vehicles increases. In this project, our main aim is to reduce the number of accidents with electric vehicles by making a smart fire safety system for electric vehicles. With the rapid adoption of electric vehicles (EVs), ensuring their safety, particularly concerning fire hazards, has become paramount. This abstract presents a conceptual framework for a sophisticated fire safety system tailored specifically for EVs. The proposed system integrates advanced technologies such as battery monitoring systems (BMS), temperature and smoke sensors, machine learning algorithms, active fire suppression mechanisms, emergency shutdown features, remote monitoring capabilities, user alerts, and compliance with safety standards. By combining these elements into a cohesive system, EV manufacturers can significantly mitigate the risks associated with fires in electric vehicles, enhancing overall safety for drivers, passengers, and emergency responders. With this technique, the fire extinguisher automatically puts out the fire when it detects flames or smoke coming from the vehicle's fire zones. Numerous factors can cause an electric vehicle to catch fire. The lithium-ion battery is the primary cause of flames in electric vehicles used within them. Installing an autonomous fire extinguishing system with Internet of Things (IoT) technology can reduce potential financial loss from a fire while also raising vehicle and human safety standards. Additionally, as soon as an accident is discovered, the nearby authorities or emergency services are notified, allowing them to get to you sooner. KEYWORDS:- Accident prevention, emergency alert, controller, fire incident, IOT technology, etc.

Analisis Mekanisme Pasar Dalam Islam, Sistem Ekonomi, dan Etika Pengawasan Pasar Serta Pasar Dalam Perspektif Sejarah Islam

This abstract discusses the role of market mechanisms in an Islamic perspective, as well as the implications and application of Islamic economic principles in the market system. Using the literature review method, this research collects, evaluates, and synthesizes relevant literature to gain an in-depth understanding of the topic. The results of the analysis show that markets in Islam are seen as a natural mechanism for exchanging goods and services, with prices determined by the forces of demand and supply. Islamic economic principles, such as justice, expediency, and the prohibition of usury, are the foundation for a fair and sustainable market system. Apart from that, the importance of market supervision and compliance with market ethics is also emphasized to maintain balance and fairness in economic activities. The analysis also highlights prohibitions in Islamic transactions that can cause market distortions. In addition, this abstract presents a comparison between conventional economic systems (capitalist, socialist, and mixed) with Islamic economic systems, which are based on sharia principles. Thus, this research contributes to understanding the concept of market mechanisms in Islam and formulating economic policy recommendations that are in accordance with Islamic values.

Mechanics 4.0 and Mechanical Engineering Education

Industry 4.0 is an industrial paradigm that is causing changes in form and substance in factories, companies and businesses around the world and is impacting work and education in general. In fact, the disruptive technologies that frame the Fourth Industrial Revolution have the potential to improve and optimize manufacturing processes and the entire value chain, which could lead to an exponential evolution in the production and distribution of goods and services. All these changes imply that the fields of engineering knowledge must be oriented towards the concept of Industry 4.0, for example, Mechanical Engineering. The development of various physical assets that are used by cyber-physical systems and digital twins is based on mechanics. However, the specialized literature on Industry 4.0 says little about the importance of mechanics in the new industrial era, and more importance is placed on the evolution of Information and Communication Technologies and artificial intelligence. This article presents a frame of reference for the importance of Mechanical Engineering in Industry 4.0 and proposes an extension to the concept of Mechanics 4.0, recently defined as the relationship between mechanics and artificial intelligence. To analyze Mechanical Engineering in Industry 4.0, the criteria of the four driving forces that defined mechanics in the Third Industrial Revolution were used. An analysis of Mechanical Engineering Education in Industry 4.0 is presented, and the concept of Mechanical Engineering 4.0 Education is improved. Finally, the importance of making changes to the educational models of engineering education is described.

In Vitro In Vivo Extrapolation and Bioequivalence Prediction for Immediate-Release Capsules of Cefadroxil Based on a Physiologically-Based Pharmacokinetic ACAT Model.

Physiologically based pharmacokinetic (PBPK) modeling is a mechanistic concept, which helps to judge the effects of biopharmceutical properties of drug product such as in vitro dissolution on its pharmacokinetic and in vivo performance. With the application of virtual bioequivalence (VBE) study, the drug product development using model-based approach can help in evaluating the possibility of extending BCS-based biowaiver. Therefore, the current study was intended to develop PBPK model as well as in vitro in vivo extrapolation (IVIVE) for BCS class III drug i.e. cefadroxil.A PBPK model was created in GastroPlus™ 9.8.3 utilizing clinical data of immediate-release cefadroxil formulations. By the examination of simulated and observed plasma drug concentration profiles, the predictability of the proposed model was assessed for the prediction errors. Furthermore, mechanistic deconvolution was used to create IVIVE, and the plasma drug concentration profiles and pharmacokinetic parameters were predicted for different virtual formulations with variable cefadroxil in vitro release. Virtual bioequivalence study was also executed to assess the bioequivalence of the generic verses the reference drug product (Duricef®).The developed PBPK model satisfactorily predicted Cmax and AUC0-t after cefadroxil single and multiple oral dose administrations, with all individual prediction errors within the limits except in a few cases. Second order polynomial correlation function obtained accurately predict in vivo drug release and plasma concentration profile of cefadroxil test and reference (Duricef®) formulation. The VBE study also proved test formulation bioequivalent to reference formulation and the statistical analysis on pharmacokinetic parameters reported 90% confidence interval for Cmax and AUC0-t in the FDA acceptable limits.The analysis found that a validated and verified PBPK model with a mechanistic background is as a suitable approach to accelerate generic drug development.

Numerical investigations of the extensive entanglement Hamiltonian in quantum spin ladders

Entanglement constitutes one of the key concepts in quantum mechanics and serves as an indispensable tool in the understanding of quantum many-body systems. In this work, we perform extensive numerical investigations of extensive entanglement properties of coupled quantum spin chains. This setup has proven useful for e.g. extending the Lieb–Schultz–Mattis theorem to open systems, and contrasts the majority of previous research where the entanglement cut has one lower dimension than the system. We focus on the cases where the entanglement Hamiltonian is either gapless or exhibits spontaneous symmetry breaking behavior. We further employ conformal field theoretical formulae to identify the universal behavior in the former case. The results in our work can serve as a paradigmatic starting point for more systematic exploration of the largely uncharted physics of extensive entanglement, both analytical and numerical.

Modeling and mathematical approach for mechanical natural frequencies of structural plates with free edges

The current study aims to demonstrate an easy mathematical procedure and simple to be used by engineers to maintain the mechanical natural frequencies (Eigen values of free vibration) of thin rectangular structural plates with free edges included in boundary conditions. The reason for this easiness and simplicity is that new method of analysis depends mainly on using mechanical minimum energy concept represented in the Rayleigh–Ritz method with appropriate real polynomials as admissible functions. The new procedure guides these functions to satisfy the boundary conditions at the middle points on the free edges of the plate beside the nodal points of the vibration modes along each edge direction. Therefore, there are no complicated or imaginary terms in the developed functions while they lead to surprisingly acceptable and even accurate results when compared with other works and Ansys program models.

Emerging Concepts of Mechanisms Controlling Cardiac Tension: Focus on Familial Dilated Cardiomyopathy (DCM) and Sarcomere-Directed Therapies.

Novel therapies for the treatment of familial dilated cardiomyopathy (DCM) are lacking. Shaping research directions to clinical needs is critical. Triggers for the progression of the disorder commonly occur due to specific gene variants that affect the production of sarcomeric/cytoskeletal proteins. Generally, these variants cause a decrease in tension by the myofilaments, resulting in signaling abnormalities within the micro-environment, which over time result in structural and functional maladaptations, leading to heart failure (HF). Current concepts support the hypothesis that the mutant sarcomere proteins induce a causal depression in the tension-time integral (TTI) of linear preparations of cardiac muscle. However, molecular mechanisms underlying tension generation particularly concerning mutant proteins and their impact on sarcomere molecular signaling are currently controversial. Thus, there is a need for clarification as to how mutant proteins affect sarcomere molecular signaling in the etiology and progression of DCM. A main topic in this controversy is the control of the number of tension-generating myosin heads reacting with the thin filament. One line of investigation proposes that this number is determined by changes in the ratio of myosin heads in a sequestered super-relaxed state (SRX) or in a disordered relaxed state (DRX) poised for force generation upon the Ca2+ activation of the thin filament. Contrasting evidence from nanometer-micrometer-scale X-ray diffraction in intact trabeculae indicates that the SRX/DRX states may have a lesser role. Instead, the proposal is that myosin heads are in a basal OFF state in relaxation then transfer to an ON state through a mechano-sensing mechanism induced during early thin filament activation and increasing thick filament strain. Recent evidence about the modulation of these mechanisms by protein phosphorylation has also introduced a need for reconsidering the control of tension. We discuss these mechanisms that lead to different ideas related to how tension is disturbed by levels of mutant sarcomere proteins linked to the expression of gene variants in the complex landscape of DCM. Resolving the various mechanisms and incorporating them into a unified concept is crucial for gaining a comprehensive understanding of DCM. This deeper understanding is not only important for diagnosis and treatment strategies with small molecules, but also for understanding the reciprocal signaling processes that occur between cardiac myocytes and their micro-environment. By unraveling these complexities, we can pave the way for improved therapeutic interventions for managing DCM.

A Novel Accelerated Multistage Learning Control Mechanism via Virtual Performance Reduction.

This study uses a multistage learning mechanism concept to investigate the accelerated learning control for stochastic systems. In this mechanism, the learning iterations are divided into successive stages, with each stage comprising several iterations. The learning gain is constant in each stage to accelerate the learning process and decreases it from one stage to another to eliminate the noise effect asymptotically. The critical issue is determining the switching iteration when a new stage starts. This study resolves this issue by calculating a virtual performance index of the mean-squared input error and its estimated upper bound. Specifically, the ideal, practical, and improved multistage learning control schemes are proposed to determine the switching iteration and generate the learning gain sequence. The ideal scheme achieves the best performance at the cost of a large computation burden, and the practical scheme saves computation cost, but the performance is not excellent. The improved scheme significantly approximates the best performance by introducing additional stretching parameters to the performance index. Illustrative simulations are provided to verify the theoretical results.

Dual attention-enhanced SSD: A novel deep learning model for object detection

Object detection is a fundamental task in computer vision with significant implications across various applications, including autonomous driving, surveillance, and image understanding. The accurate and efficient detection of objects within images is crucial for enabling machines to interpret visual information and make informed decisions. In this paper, we present an enhanced version of the Single Shot MultiBox Detector (SSD) for object detection, leveraging the concept of dual attention mechanisms. Our proposed approach, named SSD-Dual Attention, integrates dual attention layers into the SSD framework. These dual attention layers are strategically positioned between feature maps and prediction convolutions, enhancing the model's ability to capture informative feature representations across a wide range of object scales and backgrounds. Experimental results on the PASCAL VOC 2007 and 2012 datasets validate the effectiveness of our approach. Notably, SSD-Dual Attention achieves an impressive mean Average Precision (mAP) of 78.1%, surpassing the performance of SSD models enhanced with attention mechanisms such as SSD-ECA, SSD-CBAM, SSD-Non-local attention and SSD-SE attention, as well as the original SSD. These results underscore the enhanced accuracy and precision of our object detection system, marking a substantial advancement in the field of computer vision. Code is available at https://github.com/AlexHunterLeo/Dual-attention-Enhanced-SSD-A-Novel-Deep-Learning-Model-for-Object-Detection

DEVELOPMENT OF A MECHANISM FOR MANAGING THE COMPETITIVENESS OF AN INDUSTRIAL ENTERPRISE IN THE NEW REALITY

The article examines the methodological foundations of the content of the mechanism for managing the competitiveness of an industrial enterprise, due to the need for its concretization in the strategic management system in a new reality. The concept and principles of the enterprise competitiveness management mechanism are clarified, a set of measures and its differentiation according to certain criteria are recommended. In the strategic planning of the enterprise, it is proposed to use a number of modern methods and models to analyze the assessment of the competitiveness of the enterprise. A comparative analysis is carried out on the basis of methodological approaches based on the evaluation criterion of competitiveness of enterprises that are structurally independent of the system and dependent on the interconnection in the system.

Formulation of stress intensity factor under pure bending condition in multilayer pavements using numerical study and model tree approach

AbstractThe tensile deformation of top‐down cracks significantly influences pavement delamination. Accurately formulating the stress intensity factor (SIF) is crucial for assessing the stress/strain near crack tips. In the present study, a robust data mining method called M5´ is employed to formulate the SIF induced by pure bending in a multilayer pavement. A comprehensive database is generated through two‐dimensional finite element analysis to train the M5’ model. Several key parameters pertaining to asphalt and base layers are incorporated into the formulation. A comparative analysis is conducted to evaluate the performance of the developed model against traditional regression methods. A comparison of the developed model with other existing methods confirms its superior performance. Additionally, a parametric study validates the robustness of the developed model in capturing fundamental concepts of fracture mechanics. Finally, a sensitivity analysis is performed to determine the most critical parameters in the development of a predictive model for SIF.

Discrete-to-continuum modeling of spider silk fiber composites

This work presents a discrete-to-continuum approach to the constitutive response of composite materials formed by embedding a network of spider silk fibers in a matrix material. A multiscale model that makes use of the virial stress concept of statistical mechanics is formulated, which accounts for hyperelastic constitutive equations of the component materials. The finite element implementation of the given constitutive equations is also carried out. Numerical simulations show the response of a silk composite formed by embedding a spider orb web in a matrix material, and illustrate the main features of the proposed model. In the presence of a weak matrix, the force–displacement response of a silk composite is compared with that deriving from an atomistic modeling of the spider orb web. A simulation of the response of a composite equipped with an elastomeric matrix is also discussed.

EXERGOECONOMIC ANALYSIS OF A HYBRID SYSTEM OF WASTE INCINERATION AND ABSORPTION REFRIGERATION

The current global scenario presents a significant increase in energy demand for HVAC-R (Heating, Ventilation, Air Conditioning and Refrigeration) systems. Considering also that Brazil has the sixth most expensive energy in the world and that there is currently a greater scarcity of natural resources for energy generation, it is necessary to seek viable alternatives with lower energy consumption to the currently most used models, without any quality loss. On the other hand, absorption refrigeration and waste incineration systems can be lines of studies and research to be considered, considering that it is possible to reduce electrical energy consumption and also the environmental impacts that the usual compression refrigeration systems provide. . . In this context, one of the segments of Thermal Systems Engineering studied is the exergoeconomic analysis that comprises the concepts of Heat Transfer, Fluid Mechanics and Thermodynamics, based on the Second Law of Thermodynamics and which uses the notions of optimization and economic analysis. Therefore, this work aims to perform an exergoeconomic analysis of a hybrid system of waste incineration and absorption refrigeration, with the specific objective of developing an exergoeconomic model for the hybrid system. Absorption incinerator-refrigerator. This is an exploratory bibliographic research using an absorption refrigerator from the Center for Research and Development of Self-Sustainable Energy (NPDEAS) of the Federal University of Paraná, in which a model was made with a macroscopic approach of the mass and heat transfer phenomena of a absorption refrigeration cycle, applying the principles of conservation of mass and energy in steady state for each component of the cycle, that is, each component will be considered as a single control volume. It is expected that it will be possible to predict the behavior of the absorption refrigeration system and that it will be possible to develop a scientific analysis tool to design, control and optimize absorption refrigeration systems, using waste incineration. The highest exergy destroyed was verified in the desorber with about 0.9461 kW and through the exergoeconomic analysis of the incinerator, it was found that the cost rate associated with the product of the incineration gases was $ 39,926.31 per year.

Mechanical Wave Concepts of Thai High School Students: Comparing Learned and Unlearned Groups

Mechanical waves are one of the basic topics of physics; they are also the basis of various fields such as physical optics, geophysics, engineering, and medical physics. This study aims to investigate the mechanical wave concepts of Thai high school students. Participants were 150 grade 11 – 12 students from a high school in Songkhla Province, Thailand. They were divided into two groups. The first group consisted of 77 students – grade 12 who had already learned about mechanical waves, and the second group consisted of 73 students – grade 11 who had not yet learned about the topic. The main instrument was the Mechanical Wave Conceptual Survey (Tongchai, Sharma, Johnston, Arayathanitkul & Soankwan, 2009) which consisted of 22 multiple-choice questions. The researchers also asked students to provide their reasoning for choosing their answers for each multiple-choice question. The survey was administered to students and they were given 50 minutes to complete it. Students’ answers and their reasoning were analyzed quantitatively and qualitatively. As a result, students’ responses were categorized into four main topics: 1) propagation; 2) superposition; 3) reflection; and 4) standing waves. Responses from both groups of students indicated the same misconceptions.

Mechanics of blood flow through narrow artery using Prandtl viscoelastic model

BackgroundThe mechanics of blood flow via converging diverging conduits is an intriguing phenomenon that involves multiple fundamental principles of fluid dynamics. Blood arteries can diverge, which means they expand, or converge, which means they contract down. This specific structure is essential for controlling blood flow and preserving adequate circulation across the body. The theory of fluid mechanics is significant concept related to blood flow along converging/divergent channels. Elevated shear strains near the narrower artery throat can stimulate platelets, causing thrombosis that can completely or partially stop blood supply to the human brain or heart. This communication addresses the blood flow in convergent and diverging artery using fundamental concept of fluid mechanics. The Prandtl fluid model is considered as a blood, because of its viscoelastic nature. The influence of heat source, frictional dissipations and a chemical reaction are included. MethodsThe Jaffrey-Hamel flow in a converging and diverging conduits is generalized to Prandtl fluid model considering the purely radial flow through cylindrical pipe like artery with an arbitrary cross section. The governing equations are solved computationally using the Runge–Kutta-Fehlberg (RKF-4) method. Significant findingThe rheological parameters ε and δ of blood show opposite tendencies for blood circulation. The Brownian and thermophoresis parameters has a significant effect on heat and mass transport rate. The presence of slip (semi blockage) produces flow reversal and higher drag forces at the arterial wall. Significant flow dynamics and heat-mass transport was reveled for diverging (wider) artery β > 0. The non-uniform heat source show similar trends for thermal profile and heat transfer rate.

Inner Front Cover Image

ON THE INNER FRONT COVER: Hs27 fibroblasts stained for Vinculin (green) and F‐actin/phalloidin (red) on etched grooved quartz, illustrating the concept of a focal adhesion confinement mechanism in contact guidance at shallow groove depths.Credit: Jinny L. Liu & Michael C. Robitaille (U.S. Naval Research Laboratory, USA) image

Exploring students’ views about basic concepts in introductory quantum mechanics

Literature in physics education shows that students still experience difficulties learning quantum mechanics, although it is now part of the high school curriculum and many research-based proposals are available. Prior works mostly focused on specific misconceptions and a clearer picture of students’ ideas on general quantum concepts is still lacking. We addressed these issues by inspecting, through multiple correspondence analysis and cluster analysis, the responses given by 408 Italian high school and undergraduate students to a Likert scale questionnaire on quantum physics. From our preliminary results, we can conclude that the majority of students leave high school and enter university without a sound model of the quantum world.