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Radial Kernels Collocation Method for the Solution of Volterra Integro-Differential Equations
Get PDFRadial kernel interpolation is an advanced method in approximation theory for the construction of higher order accurate interpolants for scattered data up to higher dimensional spaces. In this manuscript, we formulate a radial kernel collocation approach for solving problems involving the Volterra integro-differential equations using two radial kernels: The Generalized Multi-quadrics and the linear Laguerre-Gaussians. This was achieved by simplifying the Volterra integral problem\u27s solution to an algebraic system of equations. The impact of the shape parameter present in every kernel on the method\u27s accuracy is examined and found to be significant. Two examples were used to illustrate the process; the numerical results are shown as tables and graphs. MATLAB 2018a was employed in the process
Boundary Layer Modelling of Flow Acceleration and Energy Transfer Effects in Smart Pavement Design
Get PDFThe integration of remote technology into the construction industry has advanced the emergence of smart, self-learning infrastructure across all levels of land transportation design and development. However, energy harvesting capabilities for smart road ventilation purposes have not yet been fully researched as the world gravitates towards energy sustainability. This study thus presents a mathematical investigation of the self-draining design potentials of road pavements, leveraging on energy absorption and conversion to accelerate conductive and convective ventilation of these pavements during wet conditions, as a means of ensuring the skid resistance and safety of such pavements are not compromised. Applying numerical methods with the aid of commercial software code MATLAB®, the classical physics of fluid-surface interaction was used to model accelerated drainage of microflood off paved surfaces through methodical modification of the thickness of the boundary layer associated with the flow regime over the flat road surface. Results indicate significant influences of energy exchange, thermal, and viscous diffusivity on flow acceleration. Alterations in parameters such as the slip factor, thermally induced Brownian motion or phoretic characteristics of the fluid particles at the boundary induce accelerated flow at the surface of the pavement. The findings contribute to the advancement of smart infrastructure by offering practical insights into the potential benefits of integrating energy-harvesting technologies into road pavement systems. By optimizing flow acceleration mechanisms, smart pavements can play a crucial role in improving road safety and sustainability in urban environments
Reducing the Delay Time and Tracking Trajectory of the Robot SCARA Using the Fractional PID Controller
Get PDFIn recent years, there has been a significant increase in the study of fractional systems and fractional-order control (FOC), which has proven effective in enhancing plant dynamics, particularly in terms of disturbance rejection and response time improvement. Traditionally, the Proportional-Integral-Derivative (PID) controller has been valued for its simplicity and ease of parameter adjustment. However, as the complexity of control systems escalates, several specialised PID controllers have been designed to address specific challenges. Despite its effectiveness, the conventional PID controller often faces limitations in complex systems requiring high precision and adaptive dynamics. Researchers have increasingly focused on the Fractional Proportional-Integral-Derivative (FPID) controller to address these deficiencies. The FPID controller incorporates fractional integrators and derivatives, facilitating improved tuning of system dynamics and offering increased control over response characteristics. This study introduces a fractional integrator in PID control to improve trajectory tracking and reduce delay time in Selective Compliance Articulated Robot Arm (SCARA) systems. Unlike traditional PID controllers, which may struggle with high-frequency noise and parameter variations, the fractional integrator offers enhanced noise suppression and adaptability. The fractional PID approach is relevant beyond robotics, including many systems like temperature control, electrical motor regulation, power electronics, and biomedical control systems, where accuracy and resilience to disturbances are essential. Unlike traditional PID, the proposed technique offers more adaptability in handling transient responses and greater disturbance suppression, making it a viable solution for modern, complex control environments
Towards Automation of the FORM/BCS Method
Get PDFThe software industry is facing more complex computer systems, with short development and sustainability issues. To deliver good software with these constraints, software reuse has become a central concept for minimizing design and realization costs. This study improves upon Feature-Oriented Reuse Method with Business Component Semantics (FORM/BCS), a software development method that produces adaptable architectures from reusable domain components. This is a promising method for reusable software assets and model creation. The objective of the FORM/BCS is to bring the industrial production chain to the software. This study proposes a model to automatically transform the FORM/BCS business subsystem component into a process business component. Two metamodels for business subsystems and process business components were developed. In addition, this study establishes correspondences between the source metamodel and target metamodel classes, transformation rules, and the instance of the source metamodel and generates the target metamodel instance. Detailed findings can help practitioners reduce software design costs and development time, and contribute to the advancement of knowledge in software engineering
Dynamics and Bifurcation for One Non-linear System
Get PDFIn this paper, we observed the ordinary differential equation (ODE) system and determined the equilibrium points. To characterize them, we used the existing theory developed to visualize the behavior of the system. We describe the bifurcation that appears, which is characteristic of higher-dimensional systems, that is when a fixed point loses its stability without colliding with other points. Although it is difficult to determine the whole series of bifurcations that lead to chaos, we can say that it is a common opinion that it is precisely the Hopf bifurcation that leads to chaos when it comes to situations that occur in applications. Here, subcritical and supercritical bifurcation occurs, and we can say that subcritical bifurcation represents a much more dramatic situation and is potentially more dangerous than supercritical bifurcation, technically speaking. Namely, bifurcations or trajectories jump to a distant attractor, which can be a fixed point, limit cycle, infinity, or in spaces with three or more dimensions, a foreign attractor
HetroTraffSim: A Novel Traffic Simulation Software for Heterogeneous Traffic Flow
No full textTraffic simulation software (TSS) is employed for planning, designing, and managing road networks. Among existing TSS, only SUMO and HETROSIM can be used for heterogeneous traffic. The objective of this work is to develop new software for heterogeneous traffic simulation which is effective and efficient. This is motivated by the fact that traffic in developing countries is typically heterogeneous. The HetroTraffSim TSS was developed using Unity3D and is based on a recently developed macroscopic traffic flow model. A 360 m section of University Road which is a two-lane arterial road in Peshawar, Pakistan, is used to evaluate the performance using real traffic data. The results obtained show that an increase in density decreases the velocity. Further, HetroTraffSim can be used to characterize and predict heterogeneous traffic behavior
Recycling of Waste Cartons and Musanga cecropioides Heartwood into Composite Panels for Structural Application
Get PDFIn this research, the suitability of composite panels developed from waste carton paste (WCP) and Musanga cecropioides heartwood particles (MHP) was assessed for structural applications. Proportions of the MHP adopted were 0, 25, 50, 75, and 100 % by weight of the composite mix. For each formulation, three representative samples were fabricated and also subjected to various tests. The results of the tests showed variations in the mean values of water absorption (8.83 – 30.35 %), thickness swelling (3.72 – 10.84 %), bulk density (342.3 – 461.6 kgm-3), thermal conductivity (0.1166 – 0.1717 Wm-1K-1), thermal diffusivity (2.051 – 2.397 x 10-7 m2s-1), and flexural strength (1.388 – 9.636 MPa) as proportion of the MHP decreased from 100 % to 0 %. On the contrary, a positive correlation was observed in the cases of specific heat capacity (1.552 – 1.661 x 103 Jkg-1K-1) and solar radiation absorptivity (12.32 – 13.32 m-1) with respect to increase in the proportions of the MHP used. Though all the samples exhibited better performance tendencies for thermal insulation compared to conventional ceilings or partition elements used in buildings, it was observed that samples developed with more than 50 % of the MHP could not withstand nailability. Above all, waste cartons and Musanga cecropioides heartwood are promising raw materials to be considered for fabrication of low-cost composite thermal insulation panels suitable for application in building designs. This undertaking could also serve as a safe way of managing them as wastes
Synergistic Photocatalytic Reduction of Hexavalent Chromium Using Graphene Quantum Dots and Formic Acid Optimization and Kinetics
Get PDFGraphene Quantum Dots (GQDs) has garnered a significant deal of interest in environmental remediation, particularly for reducing hexavalent chromium [Cr (VI)] to trivalent chromium [Cr (III)]. This study focused on the photocatalytic process of Cr (VI) degradation using GQDs and Formic Acid (FA) under Uv-vis light. Batch experiments were conducted to observe the photocatalytic process of Cr (VI) degradation under Uv-vis light irradiation at varying concentrations of GQDs, FA, and Cr (VI) and different pH levels. The characterization of GQDs includes PL, XPS, XRD, and Raman Spectroscopy. This research revealed that combining GQDs and FA for the photocatalytic process of Cr (VI) reduction is possible. As expected, this system is more effective with lower concentrations of Cr (VI). When FA was introduced, the Cr (VI) degradation efficiency ratio increased. The GQDs/FA/Uv-vis system gave the highest degradation rate at 91.1% within 30 minutes. It was also observed that the optimum pH of the solution was 5.42, where the GQDs were quickly dissoluble. The photocatalytic reduction matched first-order reaction kinetics with a rate constant (k) of 0.1085 min−1 and R2 of 0.985. The primary radical in the degradation of Cr (VI) in the GQDs/FA/Uv-vis system was CO2•−. These findings highlight the potential of GQDs and FA as efficient catalysts for the photocatalytic reduction of Cr (VI) under Uv-vis light
Evaluation and Challenges of IoT Simulators for Intelligent Transportation System Applications
Get PDFThe Internet-of-Things (IoT) constructs a vast, intricate, and perpetually evolving ecosystem exerting profound societal implications. This labyrinthine nature often culminates in errors that directly impact human lives. A significant domain where this complexity materializes is Intelligent Transportation Systems (ITS). Present tools and methodologies inadequately accommodate the complex task of testing and validation, underscoring the urgency for comprehensive review and enhancement. This study aims to present a broad analysis of existing simulators utilized for ITS simulations. It delves into the role and effectiveness of such simulation tools, highlighting their limitations and proposing research directions. This paper scrutinizes both commercial and research-oriented IoT simulators for ITS, evaluating their features and simulation environment tools. We have detailed various ITS scenarios simulated within these frameworks, intending to gauge their readiness for real-world ITS applications and to elaborate on the challenges involved in ITS infrastructure implementation. The findings suggest that despite numerous simulators aiding the evolution of solutions for IoT challenges in recent years, their utility in actual ITS implementations remain uncertain. Consequently, we explore public cloud platforms offering IoT simulation capabilities, focusing particularly on the capabilities provided by the Amazon Web Services (AWS) IoT simulation for this study. Our research outlines the pressing challenges in this field, while proposing potential solutions and flagging opportunities for further research. This study paves the way towards improving the reliability and accuracy of IoT simulators in the context of ITS, which has immense potential to enhance the quality of human life
Identifying the Causes of Delay in the Building Sector in Egypt: A Case Study of Small and Medium-Sized Companies
Get PDFDelay in the construction industry is known to be a significant issue as indicated by many studies in the past few years. The construction sector in Egypt is not an exception as a wide range of projects are suffering from time overrun. the presence of time overrun in the project is the root of other problems such as cost overrun and poor quality. Hence, one of the simplest ways of dealing with delays is by identifying the causes and sources of delays in construction projects in Egypt. Therefore, this paper discussed the causes of delay in the building sector in Egypt according to the perspective of professional parties working in different small and medium-sized companies. The main method of data collection was a questionnaire survey with small and medium-sized companies in Egypt. The participants had more than 5 years of experience in the Egyptian construction sector. The financial problems faced by owners were considered significant by two different companies which indicates that this factor is usually the reason for delays in projects in Egypt. Ineffective planning and scheduling have also proven to be important in the procedure of preventing delays as it was mentioned by all experts involved in the data collection. This study has shown that the perspective of experts working in different companies may not be the same regarding the causes of delays in the construction sector. The adequate understanding of the causes aids in proposing effective strategies that can reduce the occurrence and impact of delays