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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]

This paper discusses the dynamics and interaction of prey and predator populations in an ecosystem consisting of two zones, namely the reservation zone and the unreserved zone. The prey population in the ecosystem can migrate from the reservation zone to the unreserved zone and vice versa, while the predator population is assumed to be looking for prey in the unreserved zone. The dynamics of predator and prey are expressed in the form of a system of differential equations based on food intake capacity and some other factors. In the interaction mechanism between the prey and the predator, the Holling type III predation response function is considered. The existence of an interior equilibrium point of the model is analyzed and investigated for its stability using the linearization method and the Routh-Hurwitz stability test. There is a certain condition where, with the appropriate parameter values, the interior equilibrium point exists and is stable. When the migration rate from the unreserved zone is gradually increased within a certain range of values, the equilibrium point also changes but remains stable. The prey and predator populations in an unreserved zone decrease while the prey population in the reservation zone increases. Numerical simulations are carried out to verify the analytical results and the behavior of the populations. [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]

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]

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]

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]

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 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]

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]

This paper presents the results of numerical simulation of the airbag module dynamics in cars relating to the passive safety system. A mathematical model of the airbag inflation process using the corpuscular particle method was developed and implemented. This approach, as against the control volume method, allows the correct calculation of situations in which the interaction between the airbag and objects occurs before the full airbag deployment. According to the algorithm of this method, the airbag inflating process takes place under the influence of the flow of sphere-shaped particles, which are essentially ensembles of a set of real gas molecules. The implemented model allows to perform numerical calculations of the airbag interaction with the dummy model. The airbag simulator is a closed control surface modeled by a set of fully integrable shell Belichko-Tsay finite elements. A model of multilayer fabric orthotropic material was used as a model of the mechanical behavior of the airbag material. A model of the mechanical behavior of the airbag material is a model of multilayer fabric orthotropic material. The created mathematical model makes it possible to investigate the processes of functioning of newly developed and tested airbag modules for advanced vehicles. The developed model was verified by comparison with an experiment on airbag deployment. [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]

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]

Additive technology (AM) using selective laser melting (SLM) is widely used to produce parts with complex shapes made of metal alloys, composites and ceramics. One of the main problems of SLM is ensuring dimensional accuracy. The paper presents the study of the influence of selected parameters of the SLM process, such as laser power, scanning speed, distance between tracks, powder layer thickness and volumetric energy density on the dimensional accuracy of the product. The mathematical model was obtained based on a dimensional analysis describing the dependence of the SLM process parameters on the dimensional deviations of the product. Computer simulation of the SLM process was carried out using COMSOL Multiphysics® software. Theoretical results were verified experimentally on Cr-Co alloys. [ABSTRACT FROM AUTHOR]

The paper analyzes the influence of the adaptive mechatronic system parameters on the process of stabilizing the step of moving materials during automatic assembly. Dependences of variances and mathematical expectations of the displacement step are obtained depending on the parameters of the system under a random external action. Numerical simulation of the operation of the algorithms used is carried out, recommendations are given for the optimal choice of system parameters. [ABSTRACT FROM AUTHOR]

In this paper, a system of nonlinear partial differential equations describing the spread of viruses in computers has been solved using the Exp-Function method, studying the solution for these types of systems helps to mitigate the effects of viruses by predicting their occurrence, in addition to that, the effect of parameters on the behavior and spread of viruses is studied. Figures are present to illustrate the effect of parameters in solving the nonlinear system. [ABSTRACT FROM AUTHOR]

The paper presents a procedure for numerical simulation of the air permeability in the transversal direction of protective face masks. Two types of three-layer face masks were considered, and their air-permeability was experimentally measured together with the masks' structural, geometric and mass characteristics. Two simulation approaches were tested with the actual thickness of the mask (Model 1-1) and a scaled model, corresponding to 4 times augmentation of the mask's thickness (Model 1-4). A total of 12 steady-state simulations were conducted with a complete comparative analysis between the two models and the two masks (porous medium). An adapted ENGYS® version of the computational code OpenFoam® was applied. The numerical results were verified with the experiments and showed a very good correlation. [ABSTRACT FROM AUTHOR]

This paper presents numerical simulations using an open boundary algorithm with modified dynamic boundary condition (mDBC) for weakly compressible smoothed particle hydrodynamics models from particle-based code Dualsphysics. The problems of piping erosion in earth dams are aimed at studying the algorithm. The case 2D model of fluid flow past around a fixed cylinder is simulated, where various values of Reynold's numbers (Re 20 to Re 100) and different viscosity terms are considered. A constant velocity with different values of viscosity for generating various Reynold's numbers is modeled. The interaction between solid particles of the cylinder and fluid particles is concerned, the cylinder is affected by the hydrodynamics force caused by the flow of fluid particles. The solid particles of the cylinder are the observation points to obtain force and pressure due to the hydrodynamics forces. As a result of the simulation which is to show the capability to model 2D fluid flow with various Reynold's numbers. Drag coefficient, lift coefficient, and Strouhal number are compared to the previous work from literature. [ABSTRACT FROM AUTHOR]

NNW-UGKS, an engineering-oriented solver package based on the Unified Gas Kinetic Scheme(UGKS) for flows covering various regimes, is briefly introduced in the current paper. Then the hypersonic flowfield around a sharp-edged vehicle at high altitude is simulated with NNW-UGKS. The aerodynamic force coefficients, the pressure, the stress and heat distributions on the surface are compared with DSMC results. Good agreements have been achieved. [ABSTRACT FROM AUTHOR]

In this paper, a two-temperature nonlinear coupled constitutive Relations (NCCR) model is utilized to simulate the flows over a flat plate. The two-temperature NCCR model is implemented by involving the rotational relaxation term for the rotational energy equation. Thus, the rotational temperature and translation temperature in the flow field could be obtained simultaneously. The flow contours and temperature profiles over the flat plate are compared with those of multiple-temperature Navier-Stokes (NS) solver. The final results show that the two-temperature NCCR model would reproduce the solutions of NS solver at Ma=2. However, it behaves quite differently from the NS solver at Ma=5. It is also noted that the rotational temperature and translational temperature are close to each other at Ma=2. In contrast, the rotational temperature and translational temperature are totally different at Ma=5. [ABSTRACT FROM AUTHOR]

The development of blast-protective devices that direct blast and shock waves resulting in HE explosion to the safest side for humans and engineering constructions remains an urgent task in modern conditions. To optimize the design parameters of blast protection means, comprehensive research is required and the development of an optimal methodology that can help to improve the existing protective characteristics of those devices. The first stage in this direction is the study of an elevated (caused at some height above ground or floor) open explosion using experimental, analytical and numerical methods. In this paper, we obtained an assessment of the parameters characterizing the explosion of a 0.2 kg TNT charge. The features of shock wave propagation in an open explosion are determined using experimental, analytical and numerical methods. Authors revealed that it is necessary to use numerical methods with caution in modeling and decision-making. [ABSTRACT FROM AUTHOR]

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]

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]

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]

The overall lateral stability of the structural system for residential buildings relies mainly on the precast concrete wall panels as a lateral resistance system. Hence, the connection between the wall panels plays a crucial role in providing structural integrity. On the other hand, the interaction effect of interfaces between the precast and post-cast concrete of the wall panel and the intermediate joint directly impacts the structural capacity and integrity of the connected parts and the overall structural system. Therefore, numerically remains challenging for many researchers to simulate the interaction of the interfaces between the concrete cast at different times. Thus, the researchers of this paper aimed to simulate the precast concrete wall-to-wall connection using Abaqus Software to investigate the impact of casting concrete at different times on the capacity of the joint and overall integrated wall panel under lateral monotonic loading. Based on the findings, the load displacement showed good composite action. However, the interaction effect of interfaces due to casting concrete at different times reduces the initial stiffness, expedites the yielding, and delays the hardening stage. On the other hand, as the displacement was applied at the top of the left panel, the load transfer mechanism between the wall panel caused stress concentration at the interfaces between the intermediate joint and the left wall panel. [ABSTRACT FROM AUTHOR]

The Seismic isolation of bridges has greatly enhanced during the last decades. The scope of the paper is carrying out an investigation on how the properties of the double concave friction pendulum (DCFP) devices influence the seismic performance of isolated multi-span continuous deck bridges. The numerical simulations are performed conceived an eight-degree-of-freedom model able to reproduce the elastic behavior of the pier, along with the assumption of both rigid abutment and rigid deck; furthermore, according with experimental evidences, a non-linear velocity-dependent behavior has been adopted for the two surfaces of the double concave friction pendulum isolators. The model has been conceived withstand a set of natural records with different characteristics. The work comes out with the statistics related to the relevant response parameters are computed in non-dimensional form with respect to the seismic intensity considering different properties of both DCFP isolators and bridge. [ABSTRACT FROM AUTHOR]

The Seismic isolation of bridges has greatly enhanced during the last decades. The scope of the paper is carrying out an investigation on how the properties of the double concave friction pendulum (DCFP) devices influence the seismic performance of isolated multi-span continuous deck bridges. The numerical simulations are performed conceived an eight-degree-of-freedom model able to reproduce the elastic behavior of the pier, along with the assumption of both rigid abutment and rigid deck; furthermore, according with experimental evidences, a non-linear velocity-dependent behavior has been adopted for the two surfaces of the double concave friction pendulum isolators. The model has been conceived withstand a set of natural records with different characteristics. The work comes out with the statistics related to the relevant response parameters are computed in non-dimensional form with respect to the seismic intensity considering different properties of both DCFP isolators and bridge. [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]

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]

In this paper, a kinematic model of a mechanically couple platoon of two car-like vehicles is developed. Two different forms of the kinematic equations of motion are derived depending of the generalized coordinates used for the system description. The kinematic model is obtained in the form of a nonlinear driftless control system which is affine in the control inputs and can be employed for the design of different types of low-speed steering controllers for the following vehicle in the vehicle platoon. A linear feedback steering control for the following vehicle in the platoon is designed. Computer simulation tests using the derived kinematic equations of motion of the vehicle platoon along a curved path are carried out, in order to evaluate the validity of the developed kinematic model of the mechanically coupled car-like vehicle platoon and steering control. [ABSTRACT FROM AUTHOR]

The use of numerical simulations to obtain drag coefficient values cd for flow around a rough cylinder in the subcritical and critical Re number regions were the aim of this paper. The model of the cylinder with the trapezoidal waves on the surface was calculated. The results from simulations were compared with standard and available experimental results obtained by measuring of a rough cylinder with similar parameters of the relative roughness and flow regime. ANSYS Fluent software using the RANS SST k-ω turbulence model was chosen for the numerical simulations. This comparative study confirms the influence of the density and shape of protrusions on the value of the drag coefficient and thus on the shift of the position of the of cd drop to lower Re numbers. [ABSTRACT FROM AUTHOR]

In this paper, the screw configuration of the intermeshing co-rotating twin-screw extruder for TPV is designed and numerically simulated. According to the mixing and conveying performance of conventional screw elements, kneading disc elements and toothed disc elements, four screw configurations in the mixing section of the extrusion system suitable for TPV mixing task are designed. The mixing process of materials in the channel under these four screw configurations is simulated by POLYFLOW software, and the results are analyzed to select the best screw configuration. [ABSTRACT FROM AUTHOR]

In this paper, the filling process of micro-fluidic chip is simulated by Moldflow software. The volume shrinkage, cavitation, weld line and warpage deformation were studied. The simulation results show that the micro-fluidic chip can be completely filled and the surface molding quality can meet the application requirements. The numerical simulation results can predict the quality of injection molding micro-fluidic chip in actual production, and have important guiding significance for the optimization of process parameters and the design and modification of mold. [ABSTRACT FROM AUTHOR]

The trend towards the application of external thermal insulation composite systems (ETICS) on energy efficient façades under hot climatic conditions, is becoming increasingly important for energy saving in summer (summer heat protection). However, both the construction and the performance of the system should be investigated to ensure the functionality and the avoidance of damage. In this paper, the development and the functionality of ETICS as well as the analysis of measurement data for solving building-climatology challenging planning tasks in warm countries is presented. Related to the measurement data collected in a real case study, the results of a hydrothermal simulation tool are validated. Based on this, the use of thermal insulation under hot climatic conditions, for energy saving in summer, has been verified and the implementation into a simulation model is shown. For the verification of results, a case study in the campus of the American University in Ras al Khaimah (RAKRIC), in United Arab Emirates (UAE) was chosen, in which interior and exterior temperature and relative humidity values were measured. Even with the peculiarity of an irregular user behavior of the building, good accordance between measured and calculated values could be achieved. The optimized building design, facilitating a damage-free operation and a low building energy consumption, is presented in detail and essential optimization steps are discussed. Based on the analysis and evaluation of measurement data as well as the implementation of hygrothermal simulations, the presented study provides a guideline for planning of ETICS with respect to southern climate conditions. [ABSTRACT FROM AUTHOR]

The paper focuses on methods for dynamic analysis used in modern construction. The analysis of experimental data of the building, after action of seismic loading is used. Described technique enables the user to simulate behaviour of the structural system of a building based on the finite elements developed and implemented in LIRA-SAPR program. The technique allows solving dynamic problems taking into account physical nonlinearity. [ABSTRACT FROM AUTHOR]