Search

The paper presents the numerical simulation of thermo-hydraulic behaviour of coolant in nuclear reactor VVER-440 under major outage conditions. Heating-up and the flow of coolant between the reactor pressure vessel and spent fuel storage pool are discussed. [ABSTRACT FROM AUTHOR]

With the aging of the world's population, geriatric organic diseases are receiving more and more attention from the medical community. And robots are not only applied in the industrial field, medical robotics is beginning to receive more attention. This paper takes human lower limb movement disorder patients as the research object, analyses the overall structure of wearable lower limb flexible exoskeleton control system, describes the control process of the whole control system, and puts forward the improvement suggestions for the design of the control system. At the same time, this paper adopts MATLAB and its Simulink simulation method to carry out kinematic simulation, and compares and analyses the simulation curves of fuzzy self-tuning Proportional Integral Derivative (PID) control method and traditional PID control method. The accuracy and stability of the fuzzy self-tuning PID control system are finally confirmed through theoretical analysis and computer simulation. The application of fuzzy self-tuning PID control algorithms in more and more mechanical fields will also contribute to the future development of robotics. [ABSTRACT FROM AUTHOR]

This paper is aimed at performing numerical simulations of the behavior of a planar model system consisting of a spherical absorber located in a supporting convex spherical cap. The derived system of nonlinear differential equations is subjected to a numerical solution. First, the time response of the system to harmonic excitation is analyzed. For this excitation, the frequency of the excitation was gradually changed, thus, resonance curves were created. This paper also examines the effect of initial conditions. For this purpose, numerical simulations of the system without an external excitation source have been performed. The results are phase portraits for selected pairs of initial conditions. [ABSTRACT FROM AUTHOR]

The application of complex nonlinear material models of concrete within the numerical simulations is currently the most used way for the purposes of modeling the nonlinear computer response of concrete structures. However, the modeling of nonlinear concrete behavior through the nonlinear material models very often brings with it the major problem. This problem can be specified as a user nescience of a large number of material model parameters which is very common. Nowadays, the solution of this problem is possible with the so called inverse analysis or identification which can be performed via the different methods and approaches. One of the most effective approach for the purposes of the inverse analysis is currently using the combination of sensitivity analysis with optimization algorithms. This mentioned approach is demonstrated within this paper in which the parameters of the material model called the Continuous Surface Cap Model are identified. Material parameter identification is performed on the basis of interaction between nonlinear numerical simulations, statistical and optimization methods and experimental data which are represented by a load-extension curve obtained from the unconfined uniaxial tensile (UUT) test. The final comparison of the experimental data with the numerically-simulated data for optimal parameter values is, of course, also part of this paper. [ABSTRACT FROM AUTHOR]

Prosthesis has been advancing since the day of its introduction, having a tremendous degree of advancement and examination in clinical field as well as in robotics. This has been an influence for researchers who made it conceivable with various types of prosthetics that are accessible these days in the market both commercially and uniquely crafted. This paper throws light on numerical simulation and design of a prosthetic leg. The work focuses on the optimization and simulation of a prosthetic leg, improving its strength and making it cost effective. The paper has described the design and analysis of two early-existed models of prosthetic leg, comparing their strength and durability through different material analysis and thereafter designing a new model with better strength, having a high deformation rate or durability, and having much cost-efficient design and material. The Finite element analysis (FEA) was done in Ansys software, the material properties and cost efficiency were kept in mind during the analysis as well as during selection of material. Prosthetics are modified for every person, remembering the utilization and actual properties. In any case, the conventional prosthetics are heavier, and the production is costly andtedious. The current study resolves this issue and proposes an elective plan for prosthetic legs. The designed prosthetic was simulated properly and has been compared with earlier existed models. The study concludes that the new design is much more efficient and user friendly that the wearer will feel comfortable, to live a normal life. [ABSTRACT FROM AUTHOR]

Electroplated plastic parts are mainly produced by injection molding of acrylonitrile butadiene styrene (ABS) or polycarbonate/acrylonitrile butadiene styrene (PC/ABS). However, polyamide (PA) has superior physical properties, but the coating quality is inferior leading to higher scrap rates up to 30 %. Besides the electroplating parameters, the coating quality depends on the surface of the injection molded part. Former published experimental investigations and analysis of three-dimensional surface key figures according to DIN EN ISO 25175 showed that injection molding parameters significantly influence the surface layer of the produced mineral-filled polyamide parts. The aim of this paper is to present causes for the differences in the surface structure of mineral-filled polyamide. Therefore, a Design of Experiments (DoE) is carried out using 3D injection molding simulation software to determine effects that cannot be measured in the real process. The results of shear rate, temperature and degree of crystallization are evaluated at four different positions on the plastic part. Furthermore, the results are related exemplarily to the height parameter Sa of the real experiment. [ABSTRACT FROM AUTHOR]

In the paper the cancellation phenomenon in bridge beams influenced by high traffic speed on high-speed railroads is discussed. The Euler-Bernoully beams model in combination with partial equations for beams and ordinary equations for a train were used. Multiple intermediate resonance which may occur in case of active vibration control makes the cancellation phenomenon not only useless but even harmful because of different speed of trains. Nevertheless, the computer simulation does not detect the multiple resonance at the speed value that is predicted by train signature method. [ABSTRACT FROM AUTHOR]

Soft Computing will be primarily accustomed give solutions to real-world problems, that aren't modelled or too tough to model mathematically. during this planned paper, an in-depth survey of varied procedure techniques like Genetic algorithmic rule and K Nearest Neighbors employed in the care trade Health diseases are included for prediction. The computer model moon-faced problems are known but health and also future analytical directions are given to predict and predict health conditions. [ABSTRACT FROM AUTHOR]

The paper presents the step by step process of modelling the movement of dispersed group of mobile robots using the MATLAB Simulink and Simscape Multibody software. As a modelled object, a group of laboratory robots, TurtleBot2, was adopted. First, the construction of a robot CAD model was described. Next, the control system developed in Simulink was described. At the end, the robot components were defined in Simscape Multibody and a group movements analysis was carried out [ABSTRACT FROM AUTHOR]

The paper focuses on the construction of information models for the technical energy systems' functioning. This is an urgent problem that arises in applications when describing the dynamics of systems of the input-output type. Constructive algorithms for solving typical inverse problems arising when evaluating the reliability of power systems are implemented. The scientific novelty of the work is due to the use of new methods based on nonclassical Volterra integral equations of the first kind as applied to the identification and automatic control problems in describing the nonlinear dynamics of technical equipment of a large electric power system. The results of a computational experiment are presented. They confirm the accuracy of the developed computational algorithms, sufficient for practical application. [ABSTRACT FROM AUTHOR]

The paper presents the results of numerical simulation of the development of localized disturbances from two synchronous sources in the laminar boundary layer of the flat plate at the flow Mach number M = 2. The calculations were performed using the FlowVision software package. Modeling was carried out at flow parameters typical for ADT-325 ITAM SB RAS. The fluctuations of the boundary layer formed from two sources are compared with the case of a single source. It is found that the amplitude and spatial scales of the disturbance from two sources are greater than in the case of a single source. [ABSTRACT FROM AUTHOR]

Quantum technology is a candidate for the sixth generation of telecommunications (6G) in 2030. This paper proposes a new quantum coding scheme in the class of Calderbank-Shor-Steane (CSS) codes based on the Reed-Muller codes, since Reed-Muller codes are one of provably classical Shannon Capacity achieving codes. This paper keeps the proposed new codes simple by making dual-containing CSS codes having Hx = Hz, such that no further search is required for Hx or Hz. The proposed quantum Reed-Muller codes are designed from the classical Reed-Muller codes with puncturing to obtain new codes with block-length of n = 7 qubits capable of error correcting t = 1 qubit error and quantum information of k = 1 qubit, of which the extension to other block-lengths are expected to be straightforward. This paper performs a series of computer simulations to evaluate the quantum word error rate (QWER) performances under the depolarizing channels. The proposed quantum Reed-Muller codes satisfy the stabilizer codes requirement, where the diagonal element of symplectic inner product (SIP) is kept zero to guarantee a successful error correction. The proposed codes have a structure with a length close to that of the perfect quantum codes. Our results confirm that the stabilizers of the proposed codes can extract the syndrome and distinguish all error patterns of any single qubit error. This paper also confirm that the simulated performances are agreed by the theoretical QWER performances indicating that the both coding design and simulation environment are correct. These results confirm that the classical Reed-Muller codes can be used directly as QECC by puncturing the parity check matrix H. The results of this paper are expected to open new ground on the invention of new quantum codes derived from the classical codes. [ABSTRACT FROM AUTHOR]

For the design of feed sections in single-screw extruders, analytical methods are increasingly being replaced by numerical methods. One possibility for numerical process modeling of solids conveying is offered by the discrete element method (DEM), which is able to calculate individual particle movements and interactions. With DEM it is possible to determine quantities that are difficult to measure and get insight into physical processes. In this paper, dissipation in the solids conveying section is calculated with the help of DEM, since conventional analytical methods until to now are not able to provide precise results due to the complexity of the pellet movement. A specific analysis of the possibilities for dissipation calculations in the solids conveying section is carried out with the software EDEM. Two fundamentally different approaches are compared. On the one hand, the temperature increase is simulated directly via a user-defined contact model, on the other hand, an average temperature increase is calculated indirectly via a macroscopic energy balance. The description of dissipated energy as a result of friction is particularly important as it leads to a direct increase in the temperature in the solids conveying section. For a correct screw design, knowledge of the temperature in this section is essential, as melting of the material inhibits effective solids conveying. Therefore, this paper focuses on the determination of the quantities of the friction work and the resulting temperature. [ABSTRACT FROM AUTHOR]

To assess the potential capabilities of computer systems (CS), indices of the realizability of solving tasks are used. These indices characterize the quality of the systems, taking into account the reliability of the CS and the parameters of the tasks. These estimates become relevant when scalable computer systems are considered. For example, 93% of the TOP 500 supercomputers are cluster-type systems that are scalable. Failures in such systems, which directly depend on the number of computing nodes, significantly reduce the efficiency of solving tasks. The paper presents a description of mathematical model of computer systems with accumulator in group servicing task flow. The mathematical model is based on the methods of queuing theory. The paper offers solutions for calculating indices that allow us to assess the fullness of the accumulator and understand how the size of the group affects the fullness of the one. The obtained analytical solutions are aimed at express analysis of the functioning of CS. [ABSTRACT FROM AUTHOR]

In the recent few years, ICT Tools are popular in education to increase student's knowledge and interest. There is still lack of awareness of what kind tools are available. This paper presents a review of some applications/tools used for educational purposes and to improve student's educational growth and knowledge especially for computer engineering students. In this digital world, tools like animation, polls, quizzes, etc. are very amazing thing to include as part of subject activity. We wrote in this paper about different ICT tools along with their pros and cons to help faculties to decide the type of tool they can embed with their teaching learning methodologies according to their subject need. [ABSTRACT FROM AUTHOR]

NORM (Naturally Occurring Radioactive Material) and TENORM (Technologically Enhanced Naturally Occurring Radioactive Material) were introduced in Government Regulation No. 33 Year 2007 as part of the chronic exposure situation. The supervision on NORM and TENORM has changed in recent years. Despite the dynamics of development during this period, the focus of supervision is concentrated minerals contain radioactive. This paper aims to identify the concept of dose assessment in the supervision of radioactive concentrated minerals. The methodology used in this paper is a literature study of regulations, international recommendations, and practices from the other countries. The activity concentration of uranium and thorium decay series, and potassium remains the main basis for supervision. The practice of Australia and Malaysia, as well as the IAEA recommendations use the concept of a graded approach. The activity concentration as a basic starting point for the next assessment process. Dose assessment means an assessment of an individual or group of people. Dose assessment should take into account the various possible exposure pathway scenarios from the source to the receptor. The exposure pathway and number of exposure scenarios depends on the variety of scenarios from location and operation/activity. Some of these variations will provide a level of difficulty in developing exposure scenarios. Dose assessment can be done by comparison of measured radionuclide concentrations to reference levels, spreadsheet analysis using dose coefficient tables, or computer modeling. [ABSTRACT FROM AUTHOR]

This paper is aimed to discuss and compare three of the most famous Control Theories on a Two wheeled Self Balancing Robot Simulation using Robot Operating System (ROS) and Gazebo. Two Wheeled Self Balancing Robots are one of the most fascinating applications of Inverted Pendulum System. In this paper, PID, LQR and Fuzzy logic controllers are discussed. Also,0 the modeling and algorithms of the robot simulation is discussed. The primary objectives of this paper is to discuss about the building of a robot model in ROS and Gazebo, experimenting different control theories on them, documenting the whole process with the analysis of the robot and comparison of different control theories on the system. [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 deals with an analytical technique used to estimate and resolve the steady-state Frank-Kamenetskii problem. A homotopy perturbation method is applied to solve the nonlinear steady-state thermal explosion in a vessel. Additionally, using the Matlab software, the numerical simulation of the problem is described in this study. The interior temperature of the vessel is estimated and analysed to variations in the Frank-Kamenetskii and geometry parameters. A graphic representation of a vessel's temperature result is provided to demonstrate the solution, and theoretical discussion is had. The results of the analytical and numerical methods show good agreement. [ABSTRACT FROM AUTHOR]

This paper reveals the stability analysis of the equilibrium points of a fractional-order predator-prey model involving Beddington-DeAngelis functional response and stage-structured on predator using an extension of the Lyapunov direct method for the Atangana-Baleanu derivative in the Caputo sense (ABC). Here, we use the ABC fractional derivative with the Mittag-Leffler kernel since it has the non-singular type of kernel which is better know to describe real-world problems mathematically. The Mittag-Leffler function helps to preserve and store model information over time. The proposed study considers linear, quadratic, and Volterra-type to construct the Lyapunov functions. Furthermore, to illustrate the validity of the results, some numerical simulations are carried out. The existence of Hopf bifurcation is also shown numerically which is driven by the order of the fractional derivative as the index of the memory. [ABSTRACT FROM AUTHOR]

Recently, a method to avoid system failure, information leakage, and vendor-lock-in has been proposed by bundling storage services of multiple cloud vendors using a broker system. We have proposed an efficient content sharing system that can shorten upload and download times by dividing the data held by each cloud vendor into chunks and redundantly distributing them in RAID. In this paper, we propose a method to reduce the management cost and at the same time suppress the damage at the time of system failure by improving this and selecting the RAID level according to the usefulness of the contents. In addition, the effectiveness of the proposed method is confirmed by computer simulation. [ABSTRACT FROM AUTHOR]

The present paper investigates the multi-dimensional case of the cubic mappings. We have investigated the properties of Mandelbrot and Julia sets for the two-dimensional case of the mappings on the plane to itself. Mandelbrot and Julia sets help to define asymptotical behavior of the trajectories. The analytical solutions of the equations for finding fixed points and the computer simulations for describing Mandelbrot and Julia sets are the main results of this paper. [ABSTRACT FROM AUTHOR]

This paper proposes the modulating functions approach for identifying coefficients in the sixth order generalized Boussinesq equation. The identifiability of the estimation problem is studied. Numerical simulations are given to demonstrate the efficiency and robustness of the proposed method in both noise-free and noisy cases. [ABSTRACT FROM AUTHOR]

Mufflers represent devices used to reduce sound and pulsations for internal combustion engines and other equipment like volumetric compressors. Depending on application they are designed to reduce low, medium or high frequency pulsations. The main design is represented by acoustic filters which use the acoustic analogy method. Dealing with low frequency pulsations this type of filters result in bulky constructions. The use of metamaterials results in a more compact design for these type of mufflers. This paper investigates by numerical simulations the transmission loss (TL) of such muffler based on acoustic black hole (ABH) metamaterial principle. In the first part of the paper the FEM results are compared with the acoustic measurements performed on an adapted impedance tube, in order to validate the model. In the second part the influences of the geometric parameters (length of the muffler, lamellae depth and thickness) will be investigated. The comparative analysis between the FEM and the measured results indicates good agreement. The geometric parameters analysis highlighted that the acoustic attenuation can be increased by using a long muffler. [ABSTRACT FROM AUTHOR]

St12T steel (X22CrMoV12-1) is characterized by high resistance to deformation, including the ability to withstand mechanical loads at high temperatures above 550 °C, which justifies its widespread use in turbine components. The main aim of the paper is determination of the model material coefficients for steel St12T after termo-mechanical exploitation. For this purpose it has been carried out termo-mechanical compression test. Afterwards the termo-mechanical compression test was repeated using tools CSD (Computational Solid Dynamics) in a numerical simulations. In the present simulation a modified Chaboche viscoplasticity model with hardening has been used. In the paper it is shown simulation of the experimental probe with a cylindrical shape, distributions of temperature, analyzed the status of the stress effort and plastic strains. The results of simulation compared with chart from termo-mechanical test is presented. [ABSTRACT FROM AUTHOR]

The paper uses three-dimensional quasi-steady molecular statics nanocutting model to perform simulative cutting of single-crystal silicon. The study is different from the past literature that those papers mostly used molecular dynamics (MD) to perform simulation of nanocutting. Regarding the simulated cutting of single-crystal silicon performed by the paper by using the nanoscale cutting model of three-dimensional quasi-steady nanoscale molecular statics method, it is a concept that the method of calculating the movement track of each atom is used to directly acquire the applied equilibrium force when each atom moves for a small distance. The paper uses optimized method to solve the equation of equilibrium force, find out the new movement position, and step by step calculate the cutting behavior in times of cutting. In order to prove the feasibility of the paper's use of three-dimensional quasi-steady molecular statics nanoscale cutting model of single-crystal silicon, the paper simulates a diamond cutting tool with rake angle at 30 degrees, being the same as Komanduri's , to conduct orthogonal cutting of single-crystal silicon workpieces at a width of two single-crystal silicon lattices and a width of four single-crystal silicon lattices. The simulation result is compared with the numerical value obtained by Komanduri. The error between them is found to be within an acceptable range, proving that the paper's simulative model of three-dimensional quasi-steady molecular statics nanoscale orthogonal cutting of single-crystal silicon is feasible. Besides, the paper not only discusses the cutting force and cutting behavior, but also analyzes the distribution of nanoscale equivalent stress and equivalent strain at the middle cross-section of silicon workpiece in orthogonal nanocutting process. [ABSTRACT FROM AUTHOR]

Curve reconstructions are widely been used in reverse engineering problems. The reverse engineering process is the creation process of computer model from its original real-life model or its prototypes. The purpose of the reverse engineering is to improve the visualization of two-dimensional data from a series of data point. This paper presents a curve fitting of cubic Bézier curve with parameter optimization by using Differential Evolution. In this research, differential evolution algorithm is used to optimize the parametric value t associated with each point so that the distance between the original images and the parametric curve is minimize. In addition, Sum Square Error (SSE) has been used to calculate the distance between the original images and the parametric curve. The proposed technique that we used in this paper provides the comparison of numerical result to solve curve fitting problem. [ABSTRACT FROM AUTHOR]

This paper presents a novel breast model system based on a UWB antenna for locating a tumor cancer. The antenna that describes total size of 35mm*20mm*1.6mm is recognized by 120 % ultra wideband and 3 GHz-11 GHz frequency rate FCC (figural communication compety) band. Evident matching of impedance is shown on suggested antenna, omnidirectional radiation model with high earning. The outcomes of measurement are clarifying the performance of suggested antenna, the antenna is being fulfilled in a system model designed with insulating characteristics of human breast able to uncover the odd objects. Detailed study of size and exact location of tumor is performed for accurate tumor detection. The maximum specific absorption rate is specified for accurate detection of breast tumor. Furthermore the outcomes indicate precise detection of tumor can be achieved with performance of suggested antenna. The breast model system was being evolved by CST (computer simulation technology). [ABSTRACT FROM AUTHOR]

In this article, a method and some results of the numerical simulation of the effective elastic properties of core samples are described. The method consists in carrying out a series of stress-strain calculations on a 3D digital model of a core sample. The digital model is a voxel structure obtained from core sample CT scan data. Based on the features of the core sample, a representative volume is determined, on which several static boundary value problems of elasticity with different boundary conditions are solved. A digital core sample model can contain up to one billion voxels and more. Therefore, the relaxation method and the finite difference method (FDM) with explicit time scheme, which do not require a large amount of RAM during the calculation, are used to solve static elasticity problems. In addition, the calculations are parallelized using the CUDA technology for high-performance GPU computing. The effective mechanical properties of the core sample are estimated by averaging over RVE generalized Hooke's law using the results of solving each static problem. The paper presents GPU calculation results for two core samples: sandstone and limestone. The calculations are carried out on full-size core samples. The comparison of results for small core fragments with CAE Fidesys is carried out for verification. [ABSTRACT FROM AUTHOR]

The relevance of research is driven by the need to expand the possibilities of an explosion action controlling to obtain a rational rock mass fragmentation, the requirements to improve the safety of mining working, as well as the economic feasibility of reducing the loss of minerals and eliminating negative environmental factors of blasting. The paper presents some regularities of the radial air gap value influence for the TNT and ANFO charges on the yield of fractions during geo-environment explosive failure. The investigation were carried out experimentally on compositional models and numerically by the Smoothed Particle Hydrodynamics method (SPH). The article considers the methodological issues of combined application of compositional axisymmetric models and computer simulation for dynamic loading problems solving of the massive to identify patterns of stress localization and rock fragmentation. The research results made it possible to determine the dependences of the change in the middle rock piece and the yield of fines on the radial air gap value. In addition, the influence of the distance to the charge on the yield of the middle rock piece at different explosive densities was established. The developed research methodology makes it possible to determine numerically the influence of various factors on the nature of stress localization and to identify the trigger effect of the geo-environment explosive failure. The results comparison of processing physical experiments and computer simulation shows that the chosen approach ensures the reliability of the research results and turned out to be very useful for analyzing and better understanding the rock massive explosive failure mechanics. The results comparison for physical experiments processing and computer simulation shows that the chosen approach ensures the reliability of the research results and turned out to be very useful for analyzing and better understanding the rock massive explosive failure mechanics. [ABSTRACT FROM AUTHOR]

In this paper the numerical approximation of a fluid-structure interaction problem is described with the main atten-tion paid to the simulation of computational models of human phonation process. The mathematical formulation of the problem is described that allows to treat the numerical simulation of the vocal folds contact resulting in the flow domain closure. The mathematical model is described, numerically approximated and numerical results are shown [ABSTRACT FROM AUTHOR]

The use of BIM technologies today largely determines the course of modernization of the construction industry. Computer modeling of structural elements of buildings and structures, the use of CAD software systems for automating work at the stages of design and technological preparation of production can reduce the time required to complete design developments, improve the quality and reliability of the design and manufacture of elements and components of steel structures. A distinctive feature of BIM technologies is the need to include in the information base all the properties of objects used in the model. This approach allows you to combine the geometric and informational parts of the project. The 3D model format facilitates the process of optimizing architectural and design solutions, comparing several competitive options. The unified model eliminates any inconsistencies that arise when combining adjacent sections of the project. The result is a solution to the problem at the initial stage, and not a departure from it, when the error is already irreparable. The technique of creating a solid-state model of a core system node is described, which allows analyzing the operability of the node at the stage of computer modeling, choosing its optimal parameters. The paper presents a visualization of models of individual parts and assemblies, taking into account all the features. The final stage of the design was the creation of a hinge assembly. There is a possibility of further investigation of the bearing capacity of the node with the help of calculation complexes based on the created solid-state model, translated into finite element packages of application programs. Modern software tools in the vast majority of cases allow you to completely or partially abandon the full-scale experiment, transferring everything to the field of computer modeling with the involvement of CAD systems. The more work is carried out using CAD systems and the more three-dimensional graphical models of new structures and assemblies are developed, the more tempting it seems to use computer analysis. The use of CAD systems makes it possible to achieve significant progress in automating the process of preparation and execution of design documentation, information support for the design and decision-making process, unification of design solutions, when using reusable design solutions, replacing field tests and mock-up with digital modeling. [ABSTRACT FROM AUTHOR]

This paper presents a chaotic jerk circuit model concerned with a stochastic fractal-fractional order α, β ∊ (0, 1] by adding external white noise to the input voltage. A new differentiation operator as the convolution of the power law is investigated. The new operators will be pointed to fractal-fractional differentiation and integration in the Riemann-Liouville (R-L) sense. Some sufficient conditions are achieved for the existence and uniqueness of solutions for considered framework by employing the Banach contraction principle. Finally, numerical simulation is provided to confirm the theoretical consequences. [ABSTRACT FROM AUTHOR]

Numerical simulations of various welding process have been investigated by researchers in the past few decades with the advent of faster computation power becoming more and more assessable. Since the welding process involves high temperatures, a coupled thermal- structural simulation becomes imperative for analyzing the post welding effects like residual stresses etc. This paper investigates various approaches, including element types, solver settings etc. and correlates the results with experimental data. The analysis of transient thermo- structural simulation was carried out for butt weld of structural steel material and both temperature and strain fields were calculated for various heat inputs and heat input rates. These results were used for a parametric study for optimization of process parameters using inbuilt optimizer. [ABSTRACT FROM AUTHOR]

Tall buildings are mostly sensitive to wind load and the effect of wind varies with respect to height, location, shape of the structure, and hence it important to calculate the actual wind loads on tall buildings. This paper investigates the effect of wind over a square building and square building with twist 45°. The stimulation is carried using Computational Fluid Dynamics (CFD) available in ANSYS Fluent software. Turbulence model k-ε is used to simulate the external flow. The building stimulation is done at a 0ͦ winf angle. The result such as wind pressure distribution on various faces of the building is obtained and hence the result proves that aerodynamically modified building shapes can help to reduce the wind load on tall buildings. Further, this paper externs in identification wake regions, flow patterns of the wind and their behaviour around the building. [ABSTRACT FROM AUTHOR]

The paper considers a method for determining the impedance of acoustic liner sample based on numerical simulation of physical processes in resonators at a grazing incidence of a sound wave. The test section of a grazing incidence impedance tube (GIIT) and a model of acoustic liner sample, consisting of 7 honeycomb cells with a depth of 27 mm and 11.9% porous perforate facesheet is simulated. Numerical simulation is based on direct solution of the non-stationary compressible Navier-Stokes equations in a three-dimensional formulation. The pressure-time signals recorded in numerical simulation are processed by the Dean method. The obtained impedance is compared with that educed on full-scale experiment data for a single-layer acoustic liner sample, consisting of 72 honeycomb cells of a similar design. The impedance eduction is performed by minimizing the residual functional, which is the total discrepancy between the calculated and experimental acoustic pressure on the wall of the GIIT. The calculated values of the acoustic pressure are determined by the numerical solution of the Helmholtz equation and the linearized Euler equations for a duct with an impedance wall. [ABSTRACT FROM AUTHOR]

The paper deals with a delayed version of prey predator model with the incorporation of modified Holling-Tanner functional response in predator population. The model highlights the loss in prey population via migration and the natural death rate due to age factor and other reasons such as prenatal death, infection etc. The model also considers the significance of delay in the predator population which is taken as a parameter of bifurcation. Local stability analysis is done in the paper and it is examined that delay is important in attaining system's stability. Hopf bifurcation is discussed in brief along with the stability of bifurcated type of periodic solutions stability by considering normal form and central manifold theories is applied. Numerical simulations asserts the theory and concludes the paper. [ABSTRACT FROM AUTHOR]

In this paper, a path tracking controller based on distance-only measurements for nonholonomic mobile robots is presented. First, a kinematic model of the robot appropriate for path tracking applications is derived. Using a look-ahead approach, a time-varying feedback controller is proposed. The stabilities properties of the closed-loop system are analyzed in case of circular and straight-line path tracking using the theory of Lyapunov, and asymptotic stability is proved. In particular, for straight-line tracking, the steady-state error is shown to be equal to zero. Numerical simulations and experiments are carried in order to validate the proposed feedback path tracking control. [ABSTRACT FROM AUTHOR]

This paper is tackling the elbows bending process using hot mandrels. Through this process the pipe is pushed over a fix or mobile mandrel, which defines the expansion and the radius of curvature and is very important that mandrel deformation to be minimum. The paper presents the finite element model developed for the process described above, the optimization of tool parameters used to obtain and validate the simulation conditions in order to evaluate the effect of different materials on mandrels performances. The numerical simulation analyses were carried out by finite element analysis software NASTRAN and LS-DYNA which has a vast array of capabilities to simulate extreme deformation problems. Results obtained following the manufacturing process FEM simulation optimization are expected to reduce the mandrel production and exploitation costs. [ABSTRACT FROM AUTHOR]

Prediction of ship hydrodynamic derivatives is essential to evaluate ship's maneuvering capabilities. In this paper, static drift simulation results are shown for a very large crude carrier ship model, KVLCC2. For simulation, a RaNS based solver, SHIP Motion, was used. The solver solves overset structured mesh using finite volume method. The simulation results were compared with experimental data. Next, linear hydrodynamic derivatives were predicted from simulation results and compared with experimental ones. The results show good agreement with experimental data and the paper concludes that the solver, SHIP Motion, is well capable to estimate hydrodynamic derivatives maintaining reasonable accuracy and economics. [ABSTRACT FROM AUTHOR]

There are a lot of researches on virtual instruments, but there are few on classical Chinese instruments, and the techniques used are very limited. This paper uses Unity 3D and Kinect camera combined with virtual reality technology and gesture recognition method to design a virtual playing system of Guzheng, a traditional Chinese musical instrument, with demonstration function. In this paper, the real scene obtained by Kinect camera is fused with virtual Guzheng in Unity 3D. The depth data obtained by Kinect and the Suzuki85 algorithm are used to recognize the relative position of the user's right hand and the virtual Guzheng, and the hand gesture of the user is recognized by Kinect. [ABSTRACT FROM AUTHOR]

The structure of a market is determined by the number of active firms in it. Over time, this number is affected by the exit of existing firms, called incumbents, and entries of new firms, called entrant. In this paper, we considered a market governed by the Cobb-Douglas utility function such that the demand function is isoelastic. Each firm is assumed to produce a single homogenous product under a constant unit cost. Furthermore, firms are assumed to be boundedly rational in adjusting their outputs at each period. A firm is considered to exit the market if its output is negative. In this paper, the market is assumed to have zero barrier-toentry. Therefore, the exiting firm can reenter the market if its output is positive again, and new firms can enter the market easily. Based on these assumptions and rules, a mathematical model was developed and numerical simulations were run using Matlab. By setting certain values for the parameters in the model, initial numerical simulations showed that in the long run, the number of firms that manages to survive the market varies between zero to 30. This initial result is consistent with the idea that a zero barrier-to-entry may produce a perfectly competitive market. [ABSTRACT FROM AUTHOR]

This paper has numerically analyzed the problem of enhanced the dynamic response of an electrohydrostatic actuators used in aerospace systems. Based on physical and mathematical model using both Matlab / Simulink and AMESim Software Student Edition some characteristics of this type of servo actuator were obtained. The results proved that a good tracking of reference is achieved and that the servo actuator meets very well the design requirements imposed in the time domain. [ABSTRACT FROM AUTHOR]

In this paper, a flowchart process was studied using the known thermal process software: Aspen Plus. Clean glycerin is obtained from biodiesel residues through fractional vacuum distillation, specifically using the ethanol recovery method in the de-acidification process. In this stage the ethanol is removed from the medium reaction and then the direct evaporation of the reactor is replaced with emphasis on alternatives for improvements in the stages of separation and purification of the biodiesel residue that meet ANP specifications. The differences observed between experimental and numerical results in terms of mass and molar flow values can be attributed to the optimization of the vacuum separator component and the distillation column in the process. The numerical simulation may not perfectly capture all the intricacies and optimizations implemented in the actual process, leading to variations in the calculated flow values. [ABSTRACT FROM AUTHOR]

This paper presents the results of the research stage focused on applications of composite materials in aviation, carried on by an international team of European Project Semester students at the National Institute for Aerospace Research "Elie Carafoli" – INCAS, as Research Partner of the University POLTEHNICA of Bucharest, as Organizer and EUROPEAN PROJECT SEMESTER Provider. The study case is a light aircraft wheel cover. The objectives are set to the determination of the body geometry by reverse engineering techniques, modeling and numerical simulations for aerodynamics and structural analysis. A scale reduced demonstrator was obtained through 3D printing. [ABSTRACT FROM AUTHOR]

This paper presents the results of a research conducted in purpose to analyze the defects and potential damages on aircraft parts due to flight environment, specifically for aircraft intake/ inlet pipes as parts subjected to the conditions of altitude flights. The objectives are set to do numerically analyzing of an aircraft inlet pipe structure with defects/ damaged by cracks, through mathematical modeling and numerical simulations for structural analysis and to investigate the consequent impact of crack damaged aircraft structure on adaptive customized maintenance planning. The results of numerical simulations for structural analysis are post-processed and correlated with safety provisions for civil and military aviation, further resulting a customized aircraft maintenance planning, which features adaptivity from the standpoint of crack detection, monitoring and plan for crack mitigation, repair and removal. [ABSTRACT FROM AUTHOR]

This paper discusses the optimization of the electron flux generated by the interaction of a laser pulse with a shaped gas jet target through numerical simulations in order to formulate experiments for the ultra-high intensity facilities under construction or recently completed. Using such gaseous targets (instead of plasmas created by vaporizing solids using a laser) is a critical step for enabling applications at high repetition rate. The use of gas jets uniquely allows high repetition rates, low debris and relaxed laser contrast operation, thus eliminating the need for replacement of solid targets during experiments requiring high repetition rates. The results obtained reveal that the accelerated electrons can be controlled by target density adjustments. [ABSTRACT FROM AUTHOR]

This paper discussed the transmission dynamics of discrete SEIR model. It is possible to determine the prerequisites for the endemic and disease-free equilibria, as well as their local stability. In addition to demonstrating the validity of our findings, the numerical simulations also display more sophisticated dynamical characteristics such as the chaos phenomena, flip bifurcation, and Hopf bifurcation. These findings demonstrate that, as compared to models for both continuous and discrete epidemics exhibits far richer dynamical features. [ABSTRACT FROM AUTHOR]

Abstract. In this paper, a prey, predator and apex predator food 4chain model4 is proposed and analyzed. The model includes the impact of fear on solution dynamics. All feeding processes in this ecological model are formulated in terms of Crowley-Martin-like functional responses. The primary goal of this work is to find the existence condition, uniqueness and boundedness of the solution. The second goal is to study the local and global stability of these solutions. Finally, the analysis results are verified by numerical simulation. [ABSTRACT FROM AUTHOR]

The paper discussed the problems related to a linear quadratic regulator (LQR) synthesis for the control implementation in a semi-active car suspension. The control is a combination between the state's feedback and compensation by the excitation. For this purpose, the state and the input disturbance are reconstructed using the observed variables. The physical nonlinearities of the controllable magneto-rheological semi-active damper are considered. The regulator structure also includes a model of the inverse magneto-rheological damper, based on neural networks. A "Quarter car model" is used for the vehicle suspension modelling as enough adequate and appropriate for real-time control. The main contribution of the research is the approach for determining the weight matrices of the regulators, based on a formulated multicriteria problem, and solved based on the Game Theory. Numerical simulations are given, allowing for comparison of the results, and confirming the effectiveness of the presented approach. [ABSTRACT FROM AUTHOR]