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Inclined MHD Effects in Tapered Asymmetric Porous Channel with Peristalsis: Applications in Biomedicine
Get PDFThis paper emphasized an inclined magnetohydrodynamics (MHD) effects in tapered asymmetric porous channel with peristalsis in the presence of slip boundary conditions. Here we considered the two-dimensional channel with a porous medium. The fundamental assumptions of long wavelength and low Reynolds number are applied in the relevant nonlinear equations for momentum, heat, and mass transfer as part of mathematical modeling. The equations subjected to slip boundary conditions have been solved numerically by the Mathematica software. Various essential physical characteristics of velocity, temperature, concentration, and heat transfer rate are captured graphically in the end. The velocity profile is found parabolic for various involved parameters. It is observed that the embedded parameters behave in the exact opposite manner when compared with temperature and concentration distributions. The sinusoidal behavior of the heat transfer rate is also displayed. The unique aspect of this effort is specifically to relate the Joule heating, Darcy resistance, and inclined magnetic field effects in peristaltic flow for a non-Newtonian Jeffrey fluid in an asymmetric tapered channel under the influence of slip boundary conditions. Such preferences have a wide range of applications in engineering, biology, and industry. The outcomes of the presented work are also proficient in the medical field for the treatment of cancer using MHD. The MHD also aids in controlling blood pressure during systolic and diastolic pressure conditions by regulating the blood flow stream
A Source-Code Maintainability Evaluation Model for Software Products
Get PDFThe maintainability index (MI) has been proposed to calculate a single number which expresses the maintainability of a system. This article presents a model for evaluating the maintainability of software products. The model improves the shortcomings observed in the maintainability assessment approaches in the quality assessment models SQuaRE (ISO25000), ISO 9126, Squale and the FCM standard. Its main innovation is to take into account the importance of entities in the system when calculating the maintainability score. This implies that the same type of defect will have a different score depending on the entity presenting it. Seven experts with several years of experience evaluated the model. They confirmed the effectiveness and usability of the model. Then, we compared our model with the Squale maintainability index and the classical maintainability index. The results show no correlation between these models. The implications are that each method gives a slightly different view of maintainability
Investigating the Influence of Chemical Reaction on MHD-Casson Nanofluid Flow via a Porous Stretching Sheet with Suction/Injection
Get PDFThis study aims to investigate the influence of chemical reaction on the flow characteristics of a magnetohydrodynamic (MHD) Casson nanofluid over a porous stretching sheet with suction/injection. The nanofluid (NF) is comprised of a base fluid with suspended nanoparticles (NPs), and the Casson fluid (CF) model is employed to capture the non-Newtonian behavior. The governing partial differential equations (PDEs) for momentum, energy, and NP concentration are derived, incorporating the effects of magnetic field, viscous dissipation, chemical reaction, and porous medium. The resulting system of nonlinear ordinary differential equations (ODEs) is solved numerically using the Runge-Kutta-Fehlberg method together with the shooting process. The effects of various physical parameters, such as magnetic field strength, porous medium, CF parameters, NP volume fraction, suction/injection parameter, and chemical reaction parameter, on the flow characteristics are examined in detail. The results reveal that faster movement is linked to higher Grashof numbers and porous mediums, but weaker magnetic fields slow it down. The suction/injection affect velocity inversely. The Prandtl and Eckert numbers have opposite effects on temperature fields. The thermophoresis and Brownian motion parameters affect the opposite trends of the concentration and temperature distributions. The concentration reduces with chemical reaction parameters and the Lewis number. Heat transfer (HT) is enhanced for higher Brownian and thermophoresis. The findings of this study can have potential applications in various engineering fields, such as microfluidics, chemical processing, and thermal management systems, where precise control of fluid flow and heat transfer is essential
Electro-Osmotic Flow of MHD Jeffrey Fluid in a Rotating Microchannel by Peristalsis: Thermal Analysis
Get PDFIn this study, we examine the rotating and heat transfer on the peristaltic and electro-osmatic flow of a Jeffery fluid in an asymmetric microchannel with slip impact. A pressure gradient and anal axially imposed electric field work together to impact the electro-osmotic flow (EOF). Mathematical modeling is imported by employing the low Reynolds number and long wavelength approximation. The exact solution has been simplified for the stream function, temperature, and velocity distributions. The effects of diverse egress quantities on the gush virtue are exhibited and discussed with the help of graphs. The shear stress and trapping phenomena have been investigated. The characterization of results has been resolved for the flow governing ingrained appropriate parameters by employing the table. Our findings can be summarized as follows: (i) Debye length has a strong influence on the conducting viscous fluid of EOF in non-uniform micro-channel. (ii) The temperature field is enhanced through the elevated values of the rotation parameter and EOF. (iii) The shear stress has oscillatory behavior and the heat transmission rate increases with the magnitude of larger values of EOF. Finally, there is good agreement between the current results and those that have already been published. This model applies to the study of chemical fraternization/separation procedures and bio-microfluidic devices for the resolution of diagnosis
Traffic Signal Controller Optimization Through VISSIM to Minimize Traffic Congestion, CO and NOx Emissions, and Fuel Consumption
Get PDFIn developing countries with heterogeneous traffic, such as Sri Lanka, it is possible to observe severe traffic congestion at intersections and traffic corridors. The main objective of this study was to demonstrate the optimization of traffic signal controllers using VISSIM microsimulation software. It aimed to minimize traffic congestion, emissions, and fuel consumption. This study focused on developing a traffic signal controller optimization program for a congested traffic corridor which consisted of a three-legged signalized intersection, a four-legged unsignalized intersection, and a three-legged unsignalized intersection. The entire corridor was modeled here, and the already signalized three-legged intersection was optimized. Traffic signal controller optimization was done separately through the built-in optimization features in VISSIM and Webster’s Method. The results showed that emissions and fuel consumption were reduced by 14.89 % in VISSIM optimization and 14.11% in optimization using Webster’s Method. Through the comparison between the VISSIM optimized signal timing and manually calculated signal timing, it was found that the signal timing optimization provides much more improved results than the manual signal timing calculations. Using the proposed methodology, the traffic signal controllers can be optimized within a short duration in very few steps without any iterations compared to the existing traffic signal controller optimization techniques. Therefore, the proposed methodology is a good alternative method to optimize the traffic signal controllers
Brain Computer Interfaces: The Future of Communication Between the Brain and the External World
Get PDFThis paper provides a comprehensive review of the current state of research on Brain Computer Interfaces (BCIs) and their potential applications. The objective of this study was to gather information from various sources, including journal articles, conference papers, and books, to analyze the advancements and limitations of BCIs. A systematic literature review was conducted using databases such as PubMed, IEEE Xplore, and Google Scholar, with specific keywords related to BCIs and their applications. The selected studies were thoroughly analyzed to identify common themes, methodologies, and key findings. The main contributions of this review include an overview of different types of BCIs, their applications in fields such as medicine, entertainment, and education, and the challenges and limitations faced by BCI technology. The findings highlight the potential of BCIs in restoring motor function, improving the quality of life for individuals with various conditions, and enhancing human-technology interaction. Furthermore, the review identifies future research directions, including signal processing improvements, exploring hybrid and multimodal approaches, conducting long-term real-world studies, addressing ethical considerations, and prioritizing user-centred design. This comprehensive analysis of existing literature provides valuable insights for researchers and practitioners in the field of BCIs and sets the stage for future advancements in this rapidly evolving domain
Architectural Features of the First Period (13th-15th Century) Tekkes in the Balkan
Get PDFIslamic religion spreading was influenced by the different local traditions among which Sufism, a religious mysticism (tasavvuf) organized under the institutions of tariqa emerged. This was followed by the emergence of as a place where divisions (orders) members were gathered known under names of tekke, zaviye, hankâh, ribat and a dervish lodge. This study elaborates several tekkes established by the Ottomans in the Balkans. Building style of the tekkes varied according to the procedures as well as manners of the order. Tekkes, which have a simple appearance, generally consist of a mosque, semahane, cellar, kitchen, cells, çilehane, selâmlık and harem. However, most of the buildings within the tekke are constructed over a large span of time. The aim of this study is to better understand the spatial setup of this organizational structure, which directly contributed to the conquest in the Balkans through the janissary corps and to the futuwwa (a set of religious and moral vocational norms) through the ahis (religious and moral vocational chamber). For this purpose, the locations of the tekkes and their architectural features, which were established successively one after the other with the conquests, have been analyzed. In final, the architectural typological of the tekkes is obtained according to the belief tradition, positioning, foundation schemes and special plans of the early period structures set within the tekke
Fatigue Life Prediction of Mistuned Steam Turbine Blades Subjected to Deviations in Blade Geometry
Get PDFThe blades of the steam turbine are subjected to bending of the steam flow, centrifugal loading, vibration response, and structural mistuning. These factors mentioned contribute significantly to the fatigue failure of steam turbine blades. Low pressure (LP) steam turbines experience premature blade and disk failures due to the stress concentrations in the root location of the blade of its bladed disk. This study of mistuned steam turbine blades subjected to variation in blade geometry will be of great significance to the electricity generation industry. A simplified, mistuned, scaled-down steam turbine bladed disk model was developed using ABAQUS finite element analysis (FEA) software. The acquisition of the vibration characteristics and steady-state stress response of the disk models was carried out through FEA. Such studies are very limited. Subsequently, numerical stress distributions were acquired and the model was subsequently exported to Fe-Safe software for fatigue life calculations based on centrifugal and harmonic sinusoidal pressure loading. Vibration characteristics and response of the variation of the geometric blade of the steam turbine were investigated. Natural FEA frequencies compared well with the published literature of real steam turbines, indicating the reliability of the developed FEA model. The study found that fatigue life is most sensitive to changes in blade length, followed by width and then thickness, in this order. Analytical life cycles and Fe-Safe software show a percentage difference of less than 4.86%. This concludes that the numerical methodology developed can be used for real-life mistuned steam turbine blades subjected to variations in blade geometry
Challenges, Strategies and Recommendations for Reengineering Engineering Education in Sub-Saharan Africa: A Review
Get PDFWith the continent of Africa occupying the front seat of underdevelopment in the world, and its population increasing exponentially, there is an urgent need to come up with strategies to tackle the underdevelopment ravaging the continent and the demand posed by its constantly growing population. Engineering through appropriate engineering education is the answer to these challenges. In this review article, some of the challenges facing engineering education in sub-Saharan Africa such as responsiveness and relevance in the design of the undergraduate curriculum, shortage in the engineering capacity, etc. were studied. The factors that influence engineering education, in general, were also discussed and the strategies that are required for producing engineering graduates capable of taking up the challenges facing the 21st century engineers in the region were highlighted. Lastly, the review presents a guide for future engineering education and recommendations on how to re-engineer engineering education in sub-Saharan Africa to produce engineering graduates who are qualified technically and otherwise
A Review of Smartphone as an Office: Security Risks and Mitigation Measures
Get PDFSmartphones have become the most popular mode of communication as well as a novel mode of work, allowing users to work from anywhere and increasing their efficiency and responsiveness. However, the flexibility and convenience of mobile phones are associated with security risks. The objective of this study was to examine the threats and risks that smartphones face and to suggest mitigation strategies. A literature searches of scientific research articles published in online journals and databases was carried out. Some of the databases used are Google Scholar, IEEE Xplore Digital Library and Science Direct. The paper concludes that smartphones are not only capable of supporting office work but can also serve as a gateway to the Internet of Things (IoT) and a tool for user interaction with numerous electronic devices. This comes with concerns about technical threats associated with cybercrime, privacy infringements, and hidden data collection tendencies. The paper recommends advanced research to enhance counter-measures to mitigate the many existing security threats as well as those that may emerge in the future