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Background: COVID-19 has become a global concern as it has ended the lives of lakhs of people. The study done by. Lin proposed the results of an analysis of a theoretical computational model of epidemiology taking into account the crucial components such as response of an individual behavior, measures taken by government, rapid transmission and emigration of fever virus to a huge extent of human population. Simple model framework has been used by them to examine the requirements of essential elements.Problem: We claim the perfect validation of the assumptions stated for the purpose of modeling and its analysis, however, the analytical solution of the presented model is not discussed. And thus have a poor potential to make computational estimates.Methodology adopted: We have tried to present and validate the mathematical/analytic solution of the developed model, considering their assumptions.Conclusion: We have reached to the outcome that the work presented by Q. Lin should be demonstrated adequately with a cautionary advice of not to consider the results and analysis of such numerical models.The current study proposed the results of an analysis of a theoretical computational model of epidemiology taking into account the crucial components such as response of an individual behavior, measures taken by government, rapid transmission and emigration of fever virus to a huge extent of human population. Simple model framework has been used by them to examine the requirements of essential elements. We claim the perfect validation of the assumptions stated for the purpose of modeling and its analysis, however, the analytical solution of the presented model is not discussed. The decision point of this work is to adequately demonstrate along with the cautionary advice of not to use the outcomes and analysis of such numerical models. [ABSTRACT FROM AUTHOR]

In this paper we study the preservation of Lyapunov functions in the numerical integration of ordinary differential equations. By means of a continuous extension and a projection technique we extend the technique proposed by Grimm and Quispel (BIT 45, 2005), so that it can be applied to other families Runge—Kutta methods such as the well known Dormand and Prince 5(4) pair. [ABSTRACT FROM AUTHOR]

Functionally Graded Materials (FGMs) is a new composite material with gradients of material composition. The FGMs introduce by scientists from Sendai, Japan. The properties of FGMs used in this paper are metal and ceramic. Metal is a material that is resistant to structural flexibility, while ceramic is a material that is resistant to high temperatures. This paper presents the free vibration of FGMs beams using the Mixed Quadratic Beam (MQB) element. This paper begins with the formulation of the MQB element, then followed by numerical analysis of free vibration on FGMs beams problems. Free vibration analysis of FGMs beams is done by solving a simple supported (SS) beam with L/h=5. The results are compared to the reference solution. From the analysis, it can be concluded that the MQB element shows promising results for beams with a large number of elements. [ABSTRACT FROM AUTHOR]

The present paper analyzes failure observed in polymer rods collided with a steel anvil under the Taylor cylinder impact experiments. The experimental and numerical analysis demonstrates that association of the failure patterns with the loading mode depends on the rod material. Two materials are considered in the paper, specifically, polymethylmethacrylate (PMMA) and polycarbonate (PC). Damage in PMMA rods at the Taylor tests is shown to be dominated by the shear load resulting in plastic deformation. In contrast, the major mechanism of damage in PC rods is governed by omni-directional (pressure) mode of load. Analysis of the damage in sections of the rods associated with the glass transition is also addressed in the present theoretical study. Failure in these polymers follows the traditional fracture wave mechanism for brittle glass-type materials due to load in the corresponding mode. Numerical analysis employs a two-phase model with improved inter-phase thermal balance accounting for the inter-phase mass, momentum, and heat exchanges during the glass phase transition, while damage being accumulated in time. The simulation results demonstrate a good correlation with the experimental results. [ABSTRACT FROM AUTHOR]

The paper deals with numerical modeling of slab in interaction with the subsoil. A 3D computational model and numerical analysis are focused primarily on taking into account physical nonlinearity. The fracture-plastic material model is used, where the parametric study is performed with different input parameters of fracture energy. For nonlinear calculation the Newton-Raphson method was chosen. The performed calculations are compared with the experiment of a fibre-reinforced concrete slab with dimensions of 2000 x 2000 mm. The slab was tested on a specialized testing device, which allowed to evaluate the load - displacement diagram. Calculation results are compared with the experimental data and finally comparison is performed. [ABSTRACT FROM AUTHOR]

Information about the third symposium on Recent Trends in the Numerical Solution of Differential Equations is presented. Topics include numerical methods for eigenvalue problems and analysis of boundedness of general linear methods. In addition, the event highlighted various studies including the use of the well-known technique of defect correction and a new practical strategy to detect stiffness based on explicit Runge-Kutta schemes.

The ABC flow for the stationary three dimensional Navier-Stokes equations is considered. The problem is formulated on the full periodic domain. The main object of the paper is the preliminary analysis of the solution curves and location of disconnected solutions from the main branch (stationary trivial solution defined by the forcing term in the ABC problem setup). It is noted that the disconnected solutions exist for two variants of the problem parametrization: A = B = C = 1 and A = B = 1,C = 2. [ABSTRACT FROM AUTHOR]

This paper deals with the problem of load-bearing capacity and deformability of wood-steel hybrid systems, depending on the selected system constellation, and the possibility of increasing system efficiency and in real conditions by applying pre-stress, in accordance with modern principles of structural conceptual design. The subject of the research is the behaviour of pre-stressed glued laminated beams with external polygonal ropes, different researched constellations, i.e. strut type hybrid systems, in real conditions. The paper is practically divided into three methodological units: theoretical and numerical analysis, and examples of practical applications, and on the theoretical basis of urban transformations of historical units. Theoretical assumptions, as well as the current and own approach to the analysis of parameters, set the theoretical basis for the analysis of these systems and the possibility of applying numerical methods in practice. Parametric analysis of the hybrid system obtained practical expressions and diagrams for use in practice, needed to determine suitable constellations of strut type hybrid system by different geometric characteristics and pre-stressed hybrid system, and for different percentages of wooden girder moisture. In order to compare these systems, the same assumptions were used for the calculation, namely: plane behaviour of the system, and to determine the effective pre-stressing, the condition of annulment of vertical deflection in characteristic cross-sections was used, i.e. achieving the effect of vertical immobility of the struts, from which the measure of pre-stressing of the deformable system was obtained. A hybrid system with a wooden girder, which has bending stiffness, is often used in construction, and the main disadvantage of such a system is the expressed deformability in real operating conditions. The basic thesis of this paper is that by external pre-stressing of glued laminated girder achieves less deformability and increases bearing capacity, while saving base material in real conditions, and is confirmed by our own parametric analysis and laboratory testing of pre-stressed hybrid systems of different constellations. The attached parametric analysis diagrams provide a sufficiently accurate orientation for finding the correct constellations of wood-steel hybrid systems and the possibility of estimating the efficiency of hybrids in real conditions, as well as the necessary pre-stressing applications. The derived expressions of the approximate procedure and the expressions for finding the effective pre-stressing force, assuming the linear behaviour of the system, give sufficiently accurate results for the design of pre-stressed hybrid systems in practice. Also, with this or similar methodology it is possible to qualitatively investigate hybrid systems with different combinations of materials. The presented conceptual solutions for the integration of hybrid systems and modern materials in specific localities represent a contribution to the development of a methodological approach to the transformation of historical urban units. [ABSTRACT FROM AUTHOR]

In this paper an EPQ model is studied for deteriorating items with non linear price and stock dependent demand under the effect of inflation. Most of the inventory model considers holding cost assumed constant but in real situation it depends on time. Therefore holding cost assumed as a function of time. Shortages are taken partially backlogged type with fixed backlogging rate. The main objective of this proposed paper is to obtain the optimal solution. The numerical analysis has been also done to verify the initiated paper. Finally, a sensitivity analysis is also made for different parameters to obtain some useful observations. [ABSTRACT FROM AUTHOR]

The document is a preface to the Proceedings of the International Conference on Numerical Analysis and Applied Mathematics 2022 (ICNAAM-2022). The conference aims to bring together leading scientists in the field of Numerical and Applied Mathematics and attract high-quality research papers. The selection of papers included in the volume was based on an international peer review process. The preface expresses gratitude to the Scientific Committee, organizers, invited speakers, and others involved in the conference. It also mentions the inclusion of the Proceedings in the AIP Conference Proceedings series. The document provides information about the conference details, the European Society of Computational Methods in Sciences and Engineering (ESCMSE), and the categories of membership in the society. [Extracted from the article]

In the paper considers a discrete model of SIRD, constructed on the basis of discrete Lotka-Volterra dynamical systems operating in a three-dimensional simplex with a degenerate skew-symmetric matrix. The sets of ignition and the end of the epidemic have been found, and the sets where the population is dying out have been found. The paper also provides a numerical analysis of the proposed model. [ABSTRACT FROM AUTHOR]

The paper deals with numerical analysis of pretensioned experimental beams exposed to loading test. Pretensioned beams were designed as model structural specimens, adjusted to real dimensions of slab bridge beams, made of common concrete and new variant of high performance concrete with compressive strength about 100 MPa. Experimental beams were exposed to loading test for verification of load bearing calculation model, as compressive strength of HPC is on the border or oversteps the validity of current design codes. Numerical analysis was performed using software IDEA statica which enables to determine cogent effect of prestressing with respect to changes in time related to construction stages. Failure and cracking load appointed on the basis of experimental loading and numerical analysis are compared and discussed. [ABSTRACT FROM AUTHOR]

Castellated beams are well contemporarily ascribable to their structural applications. The Castellated beams are manufactured by fragmenting hot-formed rolled section that is of I shape in then it is welded together. The numerical analysis is performed using ABAQUS software. Consequently flexural, shear behavior of Castellated beams, various size and shape of openings provided, depth of openings, usage of different kinds of stiffeners, columns with and without web openings are the attempts made up in different journal papers and he researchers. It is also found that the Finite element analysis of the beam shows better results. [ABSTRACT FROM AUTHOR]

The main objective of the research work is to present the free vibration analysis of plates composed of one of the materials that have good performance and can be applied in many fields like buildings. Material that has such properties is Functionally Graded Material (FGM). FGM consists of a mixture of ceramics and metals through varying volume fractions, ceramic material as a heat barrier at the high-temperature side, and metal material with rigid properties and high conductivity at the low-temperature side. In this paper, the FGM plate is investigated using the finite element method. We use 3-node Triangular Mixed Interpolation of Tensorial Components (MITC3), widely used by researchers or commercial software. The MITC3 element is a triangular element that gives good performance to analyze plate problems, especially isotropic plate problems. We performed the numerical analysis to examine the performance and convergence behavior of the MITC3 FGM plate element in the case of rectangular plates with varying length to width ratios, and the results are compared with the reference solution. [ABSTRACT FROM AUTHOR]

In this paper, buckling analysis of composite stiffened panel with different shapes stiffener under uniaxial compressive load was carried out. Buckling behavior of straight stiffened panel on different shape of stringers were studied and compared. Stiffeners are providing the stiffness to the stiffened panel. In this paper several types of shapes like Z- shape, L-shape, Hat shape, I-shape, C-shape, J-shape and T- shape were taken. Numerical analysis done by non- linear software (ABAQUS 6.14-1). Main motive of this paper understands the shape of stringers and influences of the shapes in buckling strength. Influences of stiffener with various cross section areas of stiffened panel were deciding the buckling strength of the panel. Once buckling strength was improved, relatively high stiffness of assembly is also improving. Closed sections and more fasteners providing high buckling loads. [ABSTRACT FROM AUTHOR]

The presence of lead material in lead halide perovskite absorber is always remains a major obstacle due to its toxic nature. The emergence of tin halide perovskite absorber will overcome this toxicity issue and due to its extraordinary properties such as direct band gap and compatible visible spectrum of solar cells attracts a wide attention to researchers to focus on the development of lead free perovskite solar cells. This paper comprises of the device simulation of lead-free perovskite material. In addition, effect of various hole transport layers, and the effect of absorber band gap have been studied. It has been observed from the results that along with the proper band alignment of HTM layer with perovskite layer, the mobility of HTM layer plays an important role to achieve better device performance. Furthermore, it has been concluded that Cu2O layer as a hole transport material exhibits better device performance as compare to the other HTM layer used in this paper. [ABSTRACT FROM AUTHOR]

The development of modern society is conditioned by the accelerated pace of development of technological awareness. Our urban environment is increasingly exposed to radical transformations, leaving no room for perception and adoption of the new, almost excluding the feeling of belonging to the transformed environment. Such changes, caused by the expansion of construction activity, often violate the ambient and original values, in the transformed environments of "captured" cultural and historical heritage Objects of cultural and historical heritage possess historical, artistic and aesthetic value, readability in all their historical changes and the symbolic value of the tradition of the society to which they belong. Preservation of spiritual, formal and traditional originality, with all the technical characteristics they carry with them, emphasizing the uniqueness and representativeness of heritage in a modern environment, is an imperative in preserving one's own identity. The constructive characteristics of the historical heritage building were dictated by the degree of technical knowledge, experience and intuitiveness of the builders of that time. The specificity of structural systems and construction techniques have a direct impact on the architectural character of buildings, and thus the approach to structural repair, considering the problem exclusively from the point of view of structure and application of modern methods of numerical analysis and technology, can be a cause of disavowal of these buildings.Thus, questions arise: How sovereign are new knowledge and methods over the old, or is it necessary to awaken the intuitiveness of today's builders? How to achieve compatibility of old and new, where necessary? In this paper, the case study of a specific sample of the cultural and historical heritage of Despic House will provide answers to the questions asked. Despic House, where the first theatre in Sarajevo was founded, is one of the few material evidences of life in the city at the turning point of the Ottoman and Austro-Hungarian periods. Atypical in relation to the local way of building, it is a unique example of a combination of the traditional heritage of the Ottoman period and the " breakthrough of European creativity into the culture of this area". This paper presents a complex research process of establishing the genesis of the Despic House, as well as the consequences of the influence of urban transformations in the spatial framework at the level of the architectural object and the level of the urban-architectural ensemble. On the example of established and implemented measures of structural repair of this building, the importance of a multidisciplinary approach to detailed research and conservation-restoration works for cultural and historical heritage buildings will be confirmed, taking into account its original values. [ABSTRACT FROM AUTHOR]

Information about the Recent Trends in the Numerical Solution of Differential Equations second symposium is presented. Topics discussed include the numerical method of Hamiltonian problems, new definition of stiffness with applications and numerical methods for variational inequalities. The meeting featured several mathematics experts, including L. Aceto, L. Brugnano and R. Lamour.

An application of small aerial vehicles is described in this paper which presents an optimization of the camber position ever-changing using models and numerical analysis. During this study, the mechanics performance of a wing must be investigated over a profile of camber of 20 percent length of the chord from edge. The model was initially modelled using a software package and by adjusting the morphing wing system's modularity and reconfigurability. The angle of attack is also explored following a comparative analysis of the mechanics parameters. A considerable effect of morphing flap camber profiles on mechanics performance is observed in the results. As a supplementary validation, we provide an analysis of wind characteristics through ANSYS; we obtain the pressure coefficients, lift (CL), drag (CD), and lift-to-drag ratio (CL/ CD). The correlation between the CL, (CL/CD) and drag cut back simulations for several preferred shapes is analyzed when getting the results. For that reason forward in optimizing the cambered profile when morphing edges because the mathematical analysis associated with it has been shown improvements in CL from 15% to 30% when morphing edges. [ABSTRACT FROM AUTHOR]

Members of double-symmetrical open cross-sections are widely used as columns in steel structures. In many cases columns are subjected not only to axial force but also local transverse force due to effect of beams connected to the columns. It results in compression in the column web that should be verified in the structural design. Current standard for design of joints in steel structures provides basic information for verification of this joint component. The design resistance of column web in compression is given as yielding resistance or, based on relative slenderness of the web, buckling resistance which takes into account buckling and crippling of the web that are considered using reduction factor. The complex behaviour of the column web in compression is affected by number of aspects, e.g. structural solution of the joint (bolted, welded, with or without end plate), level of normal stress resulting from axial force or possible interaction with shear. The paper focuses on selected aspects influencing the resistance of the column web in transverse compression and summarizes results of advanced geometrically and materially nonlinear numerical analysis which are compared with results determined using provisions in the standards. The numerical analysis was performed using computation system based on finite element method. As it is considered that the resistance of the column web in transverse compression is influenced also by the geometric properties of the cross-section including geometry of the flange-web transition, both rolled and welded cross-sections with various values of web slenderness were selected for the analysis. Along with evaluation of the results obtained in the frame of the study, suitability of different types of numerical models for investigation of this problem is discussed. [ABSTRACT FROM AUTHOR]

The paper reports a numerical campaign in which two point-supported elements made of laminated glass were investigated with FEM. The first element was a horizontal roof panel 3000×1500 mm2 supported at six locations and subjected to static, uniformly distributed load. The second element was a free-standing glass balustrade 900×1900 mm2 mounted to the structure by four-point supports and subjected to soft body impact. Four types of fixings were investigated: disk fixing, countersunk fixing, bonded disk fixing and countersunk fixing on a single layer. The analysis was aimed at the investigation of the influence of different point supports on the stress in the glass. For a selected connector, a comparative analysis using the FE software and an analytical method presented in DIN 18008-3 was performed. In addition, an analysis of a positive influence of a continuous handrail on the behavior of a row of free-standing glass balustrades was investigated. [ABSTRACT FROM AUTHOR]

Fourteen airfoils were selected in this research paper to build and optimize a small horizontal axis wind turbine for a low wind speed. By using Q-blade software and CFD simulations for a 0.5 m rotor radius and the tip speed ratio ranged from 3 to 10. In this paper selected airfoil such as E205, E214, E216, NACA2412, NACA4418, SG6040, SG6041, SG6042, SG6043, S1221, S2091, S7012, SD7034 were investigated. As the most suitable geometries, Airfoil E216 and SG6043 cast out by checking numerical simulations to gain more power at low Reynolds number. In this study comparing the drag coefficient, lift coefficient and lift to drag ratio with respect to angle of attack, the airfoil has been revised. A parametric optimization of the blade geometry and develop the new airfoil for small wind turbine rotor. The E216 airfoil is found to be better performance with below solidity of8.25%, while the NACA 2412 produces stronger solidityof 21.6% due to wake effects produced behind the rotor. A wind tunnel test, Q-Blade simulation and CFD analysis were performed on the design and optimized for the proposed small horizontal wind turbine rotor axis in order to apply low wind speed area. [ABSTRACT FROM AUTHOR]

The general formula proposed by Landes and Begeley [1], which has been modified for years, among which more or less complicated approaches can be distinguished for determining the J-integral in laboratory conditions. One of them is the ASTM standard [2], according to which the energy required to calculate the J-integral should be decomposed into elastic and plastic parts, and thus the factor η depending on the shape of the specimen used in laboratory tests. Some approaches, e.g. the Polish standard [3], indicate that the J-integral should be calculated without decomposing into elastic and plastic parts. The normative documents mentioned do not usually mention the dependence of the η factor on the geometrical dimensions of the specimen (except for the shape of the specimen) or the dependence on the material characteristics. As shown in [4-7], the value of the coefficient η depends on the crack length and the material characteristics, however, the influence of material constants is usually discussed in a strictly defined range. It should be noted that papers [4-7] are based on the decomposition of the coefficient η value into elastic and plastic parts. The hybrid method presented in [8] for assessing selected parameters of fracture mechanics, referring to EPRI procedures [9], allows to evaluate them without the need for tedious numerical calculations, however, unlike EPRI procedures, it does not introduce the need to decompose these parameters into elastic and plastic components. In view of this fact, in this study it was decided to assess on the basis of numerical calculations carried out for the dominance of plane strain, the effect of crack length and material constants (expressed in yield strength and strain hardening exponent in R-O law) on the value of the coefficient η which is required to estimate the value of the J-integral in accordance with by Landes and Begeley [1]. The discussion presented in [10] was the inspiration to undertake this topic. In this paper, based on a comprehensive numerical analysis of SEN(B) specimens dominated by a plane strain state, for four different crack lengths and sixteen hypothetical elastic-plastic materials (characterized by different yield strength and different level of stain hardening exponent), the values of the J-integral were estimated, the impact of the crack length and material constants on the value of J-integral was assessed, an analysis of the P=f(u) curves and discussion on the effect of crack length and material constants on the value of the factor η were presented. Using the approach given in [4-7], simplification was made in the analysis and the value of the coefficient η was determined for each analysed specimen. The analysis showed a strong dependence of the coefficient η on the crack length and the strain hardening exponent n. It turned out that the coefficient η does not depend on the yield strength of the specimen material. The results were summarized in tabular form and approximated using the Table Curve 3D program. The measurable effect of the paper is a summary of numerical results – values of the coefficient η for 64 SEN(B) specimens and a new form of the function η=f(a/W, n) which was proposed, and which allowing to take into account in the process of determining the J-integral by the factor η the geometry of the specimen (relative crack length a/W) and material characteristics (n – strain hardening exponent in R-O law). [ABSTRACT FROM AUTHOR]

An unmanned aerial vehicle (UAV) that is able to take-off and land on a medium sized ship, have greater endurance and range as compared to the previous iteration, and the ability to achieve all three flight modes - vertical, transition and horizontal flight modes is to be designed, built and tested. In this paper a comprehensive review is given on various VTOL planform configuration and a tilt-rotor configuration is selected for Minerva 2.0 for its high stability and increased efficiency. This paper covers the selection analysis of different vertical take-off and landing (VTOL) airframe as well as mechanical and electronic hardware design with the intention of increasing flight efficiency for surveillance purposes on wide sea area. This paper presents Minerva 2.0, a novel aerial platform with VTOL capabilities. Numerical and analytical analysis results are discussed. The previous iteration, Minerva 1.0 was built and tested as a QuadPlane configuration and an increased efficiency of 25 to 58.7% is achieved in this paper. [ABSTRACT FROM AUTHOR]

Today, the study of the distribution of emissions in the atmosphere is quite an urgent task, because harmful substances, getting into the surrounding atmosphere, cause harm to the health of people, flora and fauna. In this paper, the results of simulation of the distribution of emissions from the Ekibastuz TPP (GRES 1) are presented. For simulations the model of turbulence was chosen. Simulations were performed by using the ANSYS 16.0 software package. Previously, the model and numerical algorithm were tested using a model problem and the results were compared with the experimental data. [ABSTRACT FROM AUTHOR]

The Rim-driven Thruster (RDT) is a new type of marine electric thruster proposed in recent years. In this paper, the author proposed a new type of permanent magnet synchronous rim thrust motor (RTM). The motor uses a Halbach array permanent magnet rotor, which can improve the torque density of the propulsion motor by utilizing the unilateral magnetic field of the Halbach array.In this paper, the electromagnetic properties of the motor were measured and compared with that of the ordinary magnetic pole motor through numerical analysis. The results show that at the same power, the new motor can significantly reduce the thickness of the rotor's permanent magnet and yoke core, and has obvious advantages in power density, moment of inertia, dynamic performance, and cost. [ABSTRACT FROM AUTHOR]

The impact of physical loads in the automotive assembly line has been investigated in the automotive and manufacturing industries. The purpose of this paper is to systematically examine the impact of human factors on worker quality performance in designing and managing manufacturing operations. Tiredness and efficiency deficits have a good relationship. Thus, the display of fatigue graphs, and S-N curve about overloading, heavy manufacturing work in industry depicts stress and fatigue are inversely proportional to the number of cycles. Also, the authors determine the fatigue limit numerically by calculating the r-ratio or amplitude ratio. Data was collected from the rail coach factory, Kapurthala using a particular database system. [ABSTRACT FROM AUTHOR]

Wind load analysis is a critical component of tall building design, ensuring structural integrity and safety. This study investigates the wind load analysis of a specific 14-story building, employing numerical methods to assess its impact on structural design and implications for stability. Adhering to the guidelines outlined in the Australian building code, the research utilizes STAAD Pro software for numerical analysis. Through a thorough examination of wind-induced stresses and deformations, the paper offers insights into the factors influencing structural integrity and suggests potential design modifications and mitigation strategies. The findings from this study suggests that it's not always needed to focus so much on wind when designing buildings. However, careful consideration needs to be given to design changes, especially as buildings get taller. It was also observed that sometimes, the problems caused by the shape of the building can be more important than worrying about the wind. [ABSTRACT FROM AUTHOR]

In this paper, numerical analysis of reinforced concrete beams with web openings enhanced by reactive powder concrete layer was accomplished at different locations. The advantages of using RPC materials with RC beam depend on the location of RPC layers in tension zoon (bottom of web openings) or compression zoon (top of web openings). So, this numerical study aims to verify the behavior of twelve experimental RC-RPC composite beams using normal strength concrete with RPC to obtain optimal advantages. The main variables have studied the effect of the location of the RPC layers and the number of web openings on the strength of beams. By verifying the ANSYS result comparison with experimental results of beams, the mean accuracy is about 1.146, and the standard deviation is about 0.043. Numerical results showed that the final strength decreases with an increasing number of openings. It was found that the use of RPC layers effectively improved the performance of the beams compared to ordinary concrete layers. The ultimate strength of RC-RPC composite beams was increased about 1.5, 1.5 and 1.3 time by using RPC layers in the compression and tension regions compared with the identical normal concrete beams with one, two and three openings, respectively. Meanwhile, the optimum location of the RPC layer is determined at tension zoon RC-RPC composite beams. Finally, crack patterns of NC-RPC beams depend on the number and location of transverse openings, which determines the onset of cracks and the type of failure. [ABSTRACT FROM AUTHOR]

Due to the excess use of air conditioning systems led to significantly increase the demand for electric power in the household sector. Therefore, to decrease energy consumption, it can use an Earth-Air Heat Exchanger (EAHE); it has been demonstrated to be promising method for heating and cooling applications. In this paper, simulation study was performed using ANSYS FLUENT 19.0 (CFD) program as a numerical analysis on the impact of different pipe shape and air velocity on the performance according to the climatic conditions of Baghdad-Iraq in the summer and winter seasons. The pipes shapes in EAHE system that were used are spiral, wave and straight at the same length and diameter, and it has been studied their impact on performance at different speeds (5, 10 and 15 m / s). The results of numerical analysis showed that the shape of pipes and velocity of inlet air have an effect for the temperature of outlet air and performance of EAHE. Through the results obtained, it was found that the shape of straight tube presents the best performance compared to the other two shapes of spiral and wave. Therefore, the better performance for EAHE can be achieved on operating the system at low air velocity together with straight shape for the exchanger pipe. [ABSTRACT FROM AUTHOR]

Artificial lateral boundary is important in the numerical simulation of seismic responses of underground structures. In this paper, the performance of three commonly artificial lateral boundaries (i.e., tied boundary, fixed boundary and roller boundary) are compared based the nonlinear finite element simulation of an underground structure-soil system. The accuracy of the three artificial boundaries is discussed in terms of structural racking deformation and acceleration responses. For each artificial boundary, the influence of distance away from underground structure is discussed. The results show that when the distance from the edge of the structure to the lateral artificial boundary is more than 9 times its own width, the simulation errors of all kinds of artificial boundary are less than 5%. Among the three types of artificial boundaries, the calculation accuracy of roller boundary is best. Its distance is 3 times the width of the structure, which can satisfy the calculation error of both the structural acceleration response and the inter-story drift response within 5%. [ABSTRACT FROM AUTHOR]

This paper studies a new hybrid conjugate gradient (CG) method based on the Aini-Rivaie-Mustafa (ARM) CG method for solving nonlinear unconstrained optimization problems. The new hybrid method eliminates the negative values generated by the ARM method in its CG coefficient by replacing those values with a positive CG coefficient. The numerical test was conducted on 10 standard test functions from small to large scale under inexact line search. Based on the numerical results, the method proved to be more efficient compared with some older versions of CG method in terms of number of iteration and CPU time. In addition, a set of data for number of road accidents was collected from Portal Rasmi Polis Diraja Malaysia. By using discrete least squares method of numerical analysis and CG method in unconstrained optimization, the data can be estimated. Results from the error calculation for both methods showed that the proposed CG method is comparable with the least squares method. [ABSTRACT FROM AUTHOR]

In recent times, there has been an increasing interest in the study of B-spline functions. This interest stems from the attractive properties of these splines, including their local control and flexibility. The present study aims to address the scientific gap of Cubic B-spline Collocation Method (CBCM) in Numerical Analysis. The current developments and potential applications of CBCM, which can be extended to higher orders in more complex problems are explored and discussed in this study. A systematic review of the existing literature is conducted, and the following three aspects are addressed: (1) the application of conventional CBCM; (2) the advantages and disadvantages of CBCM, including the accuracy, stability, and convergence of the scheme; and (3) the potential extension of CBCM. In conclusion, this paper provides valuable insights into CBCM, thus paving the way for the improvement of its applications in Numerical Analysis. [ABSTRACT FROM AUTHOR]

Cold-formed steel product sections are abundantly utilized in the metal buildings, constructions and Industries for more than four decades. These products are found more in general in every form of working environment due to their flexibility, availability, market value, increased weight and strength ratio, easy fabrication and so on. The highly notable application is that these steel sections are obtainable in varied shapes that we can avail predominantly according to the need. The finite element method is specifically technique of numerical analysis to pertain mere elucidations to massive range of engineering crisis. This paper depicts an analysis by numerical method with bending operation of cold-formed steel built-up sections. The results obtained through the experiment are conformed through finite element analysis with ANSYS R2 Software and Manual designs. The investigational results procured are better submission to the analytical outcome. [ABSTRACT FROM AUTHOR]

This paper presents the description of the preparation of aggregate irradiation experiment including the choice of sample types and preliminary numerical prediction of aggregate RIVE and damage under defined conditions for the research reactor LVR-15. Ten different samples from four countries were selected for the experimental investigation. The preliminary numerical analysis was performed for granite as the aggregate with the highest radiation-induced volumetric expansion (RIVE). Based on the prediction, the highest RIVE of 4.54 % at high-dose neutron fluence (0.585·1020 n/cm2, with energy E>10 keV) is expected. Thus, taking into account the sample size, the inner diameter of the irradiated capsule should be about 11 mm. The aggregate samples with the highest RIVE (granite) are expected to be damaged significantly even after irradiation to low-dose neutron fluence (0.208·1020 n/cm2, with energy E>10 keV) which will be captured during the post-irradiation examination. [ABSTRACT FROM AUTHOR]

The novel coronavirus disease 2019 (COVID-19) has shown the danger that can be caused by small, airborne and contagious virus particles such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To prevent the mass spreading of such viruses, the use of electromagnetic waves could be used to combat the spreading of the virus. Particularly, the waves could force any virus particles to oscillate in resonance with the frequency of the wave and destroy themselves before the virus would enter the respiratory system. This paper describes the use of numerical simulations to analyze the effects of exposing a SARS-CoV-2 particle to electromagnetic waves at a range of frequencies and to determine which frequencies have the potential of causing resonance within the virus which would yield to the maximum energy absorption. Such technique could be utilized in preventive/protective devices and disinfection equipment. [ABSTRACT FROM AUTHOR]

This paper presents the numerical method applied to predict the performance and wave wash of the river craft. In recent years fast ferries have been introduced on many ferry routes all over the world. Mainly when operating in shallow waters and near the coast, the waves generated by these crafts give escalate to clash with recreational use of beaches and coastal waters. The performance of HSC vehicle in these areas and the potential coastal erosion caused by a changed wave impact has been a subject of concern. In this paper, a finite volume method (FVM) and RANS approach was applied to investigate the wave wash, resistance, trim, and pressure acted on the craft. Actually a dynamic mesh with two degrees of freedom was used and the results were compared with a markedly proper experimental results and the competency of applied method was proved. [ABSTRACT FROM AUTHOR]

This paper presents a study of rarefaction effect on hypersonic flow over a sharp leading edge. Both continuum approach and kinetic method: a widely spread commercial Computational Fluid Dynamics-Navior-Stokes-Fourier (CFD-NSF) software - Fluent together with a direct simulation Monte Carlo (DSMC) code developed by the authors are employed for simulation of transition regime with Knudsen number ranging from 0.005 to 0.2. It is found that Fluent can predict the wall fluxes in the case of hypersonic argon flow over the sharp leading edge for the lowest Kn case (Kn = 0.005) in current paper while for other cases it also has a good agreement with DSMC except at the location near the sharp leading edge. Among all of the wall fluxes, it is found that coefficient of pressure is the most sensitive to rarefaction while heat transfer is the least one. A parameter based on translational nonequilibrium and a cut-off value of 0.34 is proposed for continuum breakdown in this paper. The structure of entropy and velocity profile in boundary layer is analyzed. Also, it is found that the ratio of heat transfer coefficient to skin friction coefficient remains uniform along the surface for the four cases in this paper. [ABSTRACT FROM AUTHOR]

The article discusses various reports published within the issue, including one on parallel approach in solving differential equations and another on high-order block methods.

This paper deals with the numerical investigation of ellipticity of the boundary value problem for isothermal finite strain elasto-plasticity. Ellipticity can be lost when softening occurs. A discontinuity surface then appears in the considered material body and this is associated with the ill-posedness of the boundary value problem. In the paper the condition for ellipticity loss is derived using the deformation gradient and the first Piola-Kirchhoff stress tensor. Next, the obtained condition is implemented and numerically tested within symbolic-numerical tools AceGen and AceFEM using the benchmark of an elongated rectangular plate with imperfection in plane stress and plane strain conditions. [ABSTRACT FROM AUTHOR]

In the paper a kind of meshless discretization technique, called the Kansa method, is investigated in the context of problems with multiple boundary conditions. This numerical method uses interpolant composed of radial basis functions as well as collocation technique to discretize differential equations. To overcome the problem that appears for equations with multiple boundary conditions, where more equations should be associated with a boundary node than degrees of freedom that exist at this node, an extension of the method is proposed. The key idea lies in the modification of the interpolant with the use of Hermite formulation. The details of the approach are shown in the paper. Moreover, the special attention is paid to estimate respective value of the shape parameter included in radial functions to ensure stability of the solution process and high accuracy. To illustrate usefulness, accuracy and convergence of the method, it is employed to solve a test problem of the bending Kirchhoff plate. [ABSTRACT FROM AUTHOR]

The traditional Canny algorithm has poor self-adaptability threshold, and it is more sensitive to noise. In order to overcome these drawbacks, this paper proposed a new edge detection method based on Canny algorithm. Firstly, the media filtering and filtering based on the method of Euclidean distance are adopted to process it; secondly using the Freichen algorithm to calculate gradient amplitude; finally, using the Otsu algorithm to calculate partial gradient amplitude operation to get images of thresholds value, then find the average of all thresholds that had been calculated, half of the average is high threshold value, and the half of the high threshold value is low threshold value. Experiment results show that this new method can effectively suppress noise disturbance, keep the edge information, and also improve the edge detection accuracy. [ABSTRACT FROM AUTHOR]

Islamic banking in Malaysia offers variety of products based on Islamic principles. One of the concepts is a diminishing musyarakah. The concept of diminishing musyarakah helps Muslims to avoid transaction which are based on riba. The diminishing musyarakah can be defined as an agreement between capital provider and entrepreneurs that enable entrepreneurs to buy equity in instalments where profits and losses are shared based on agreed ratio. The objective of this paper is to determine the internal rate of return (IRR) for a diminishing musyarakah model by applying a numerical method. There are several numerical methods in calculating the IRR such as by using an interpolation method and a trial and error method by using Microsoft Office Excel. In this paper we use a bisection method and secant method as an alternative way in calculating the IRR. It was found that the diminishing musyarakah model can be adapted in managing the performance of joint venture investments. Therefore, this paper will encourage more companies to use the concept of joint venture in managing their investments performance. [ABSTRACT FROM AUTHOR]

This paper deals with method of B-spline solution for a system of boundary value problems. The differential equations are useful in various fields of science and engineering. Some interesting real life problems involve more than one unknown function. These result in system of simultaneous differential equations. Such systems have been applied to many problems in mathematics, physics, engineering etc. In present paper, B-spline and B-spline with free parameter methods for the solution of a linear system of second-order boundary value problems are presented. The methods utilize the values of cubic B-spline and its derivatives at nodal points together with the equations of the given system and boundary conditions, ensuing into the linear matrix equation. [ABSTRACT FROM AUTHOR]

Currently, the use of spline functions in the development of Science and technology is a topical issue. Spline features the classic interpolation has several advantages in terms of rapprochement from multiples. Based on clearly given experiments, the construction of a local interpolation cubic spline function was analyzed based on a linear combination of parabolas with 2 common points. In this paper, all the properties of the local interpolation cubic spline functions built at each interval at the connection node points are analyzed on the basis of several experimental data and on the basis of numerical processing. The continuity of local interpolation cubic spline functions at all connection nodes was checked using graphs and numerical analysis based on concrete examples. [ABSTRACT FROM AUTHOR]

In this paper, we consider the study of the extreme problem of the fictitious domain method based on the use of the Lagrange functional, with a multiplier defined on the actual boundary and associated with genuine boundary conditions. The theorem of the existence of a generalized solution of the auxiliary FDM problem is proved. The convergence of the solution of the auxiliary FDM problem is shown. For mathematical research, the theory of functional spaces and the technique of obtaining a priori estimates in functional spaces are used. To verify the effectiveness of the developed method, numerical analysis and comparison with other methods of solving the problem were carried out. [ABSTRACT FROM AUTHOR]

In the present paper, a time dependent source of identification p roblem f or a o ne d imensional d elay hyperbolic equation with Dirichlet condition is studied. The first order of accuracy difference scheme for this source identification problem is presented. Numerical analysis and discussions are presented. [ABSTRACT FROM AUTHOR]

This paper is devoted to numerical analysis of plaster detachment and numerical experiments for determination of the appropriate material parameters. Interaction between the plaster and masonry is described with the help of interface finite elements which are equipped with traction-displacement relationship. Laboratory tests were introduced in order to determine the shear capacity of the masonry-plaster connection. Unfortunately, variability of measured behaviour was very large and additional tests are needed. [ABSTRACT FROM AUTHOR]

In comparison to single-rotor wind turbines, dual-rotor wind turbines have recently been designed to increase wind capture and power generation. However, in low wind speed areas with average wind speeds of less than 4 m/s, the wind turbine struggles to function and operate at its best. In this paper, different dual rotor wind turbine geometries are designed and simulated using computational fluids dynamic software and optimized using response surface methodology to compare the performance of the wind turbine. The main objective is to investigate the effect of different blade materials on different wind speeds to the performance of the wind turbine by using ANSYS WORKBENCH R2 and choose the best blade material for the wind turbine by using Design Expert 13. Wind turbines have been analyzed at a different wind speeds of 2 m/s, 3m/s and 4 m/s. Three different blade materials are compared to the force performance in this study. The wind turbine performance was also investigated numerically. In this research work, lift force and drag force are the parameter that determines the thermal performance of the heat sinks. The findings revealed dual rotor wind turbine with carbon fiber blade was the best to be used in low wind speed areas. [ABSTRACT FROM AUTHOR]