Simulation Modeling Method Research Articles

Overview of Underwater Transmission Characteristics of Oceanic LiDAR

Oceanic LiDAR (hereafter referred to as O-LiDAR) is an important remote sensing device for measuring the near-coastal water depth and for studying the optical properties of water bodies. With the commercialization of LiDAR, the theoretical research on the underwater transmission characteristics of LiDAR has been intensified worldwide. Primary research interests include the simulation and modeling of LiDAR underwater echo signals and the inversion of optical parameters using LiDAR water echo signals. This article provides an overview of the principle of LiDAR echo signal formation, and comprehensively summarizes the LiDAR echo signal simulation modeling methods and the corresponding factors that affect modeling accuracy by focusing on the characteristics of different methods. We found that the current simulation methods of LiDAR underwater transmission echo signals primarily include an analytical method based on the radiation transfer equation and a statistical method based on the Monte Carlo (MC) model. The radiation transport equation needs to be appropriately simplified using the analytical method, usually using the quasi-single-small-angle approximation principle. The analytical method has high calculation efficiency but its accuracy is dependent to the quasi-single small-angle approximation. The statistical method can analyze the influence of various factors on echo signals by controlling the variables, but it has poor calculation efficiency. Finally, the semianalytical MC model was used to quantitatively analyze the three main factors (LiDAR system parameters, water body optical parameters, and environmental parameters) affecting underwater LiDAR transmission characteristics, and summarizes the mechanism and results of different factors.

Оценка целесообразности размещения парковочного пространства легковых автомобилей на основе имитационного моделирования

The article deals with the issues of assessing the development of parking systems of passenger cars in large cities based on the use of the simulation modeling method. With the help of AnyLogic software, a simulation model for evaluating the feasibility of parking space placement has been developed. The proposed simulation model simulates the movement of vehicles on a section of the road network (RN) and determines the number of cars that could not park due to the lack of parking spaces. Three calculators are built into the simulation model. The first calculator calculates the required number of parking spaces based on standard values, depending on the purpose of the object near which the parking space is planned. The second calculator allows you to determine the preliminary cost of the project, depending on the type of parking space. The third calculator evaluates the efficiency of the project, changes such indicators as the required number of cars, the average time spent by cars in the system under study, their average speed, the number of car stops. Using the developed model allows you to determine changes in the values of traffic flow indicators and choose the optimal type of parking space, based on a preliminary assessment of the expected economic effect.

Разработка шарнирной системы поворотного конвейера

The application of simulation modeling methods for the design of transport systems and conveyors with the rotation of lattices in the plane of the transportation surface due to rotary and rotarytranslational hinges is carried out in the Adams dynamic programming package based on Lagrange–Euler theory and using finite element technologies. As a result, the work of the conveyors can now be carried out in 3D. Such capabilities are necessary when entering the conveyor into the chamber after the tunneling combine and for transportation along with curved workings. It is also possible to use armored turning conveyors for the extraction of DBO ores. The above expressions consider the rotation of the conveyor's lattices in any zone of its installation at a given angle up to 15о and allow determining its position in the chamber, taking into account the system of special hinges located on the sides of the lattices. The features of the movement of the combine as accelerated at short intervals of the route and the model of the turning process are substantiated.

Improving methodology of automobile operating companies activities simulation modeling

This article is devoted to the study of the use of mathematical hardware in the efficient organization of the system of servicing motor vehicles. Herewith, simulation modeling methods enable obtaining information about the state of the system analyzed with the application of its programmed model. This information is then used in the design of system management. In addition, proposals have been developed to improve the car maintenance process within the framework of generating random values corresponding to the distribution of probabilities by type of service over the period of entry into the car maintenance system.

МЕТОДИКА АНАЛИЗА ФУНКЦИОНИРОВАНИЯ СЛОЖНЫХ ВОДОХОЗЯЙСТВЕННЫХ СИСТЕМ НА ПРИМЕРЕ ВОЛЖСКО-КАМСКОГО КАСКАДА ГИДРОУЗЛОВ

The article considers methodical approaches to the analysis of the current state of the management problem of water economic systems under non-stationarity of multi-year fluctuations of surface water resources. Application of the simulation modeling method for solving water management problems is substantiated. The main provisions of the analysis of initial hydrological information to control the operation regime of the Volga-Kama cascade of hydraulic units are given. Methodical provisions for the analysis of the operation regime of complex water management systems with a cascade of hydraulic units with reservoirs in its structure are formed. The operation modes of the Volga-Kama cascade of hydraulic units under the conditions of different water content of the Volga River are analyzed. The considered methodic provisions are illustrated by the examples of simulated modeling of the Volga-Kama cascade operational regime under average water content conditions. The structure of modern water management systems and their functioning is presented as an open multicomponent dynamic system. The ultimate goal of the analysis technique of the water management system with the knowledge of the regularities of hydrological system formation is development of formalized mathematical models of this system functioning and investigation of many alternative variants under different natural-economic conditions.

Integrated simulation of plasma current profile in HL-2A high confinement mode(H mode)

The plasma current (<i>I</i><sub>p</sub><italic/>), magnetic field (<i>B</i>), and safety factor distribution (<i>q</i> profile) of the HL-2A tokamak device are crucial to monitoring the steady-state operational scenarios (in high confinement mode, H mode). Based on real experimental data and integrated modeling simulation method (OMFIT), the plasma parameters’ profiles such as magnetic field configuration and current density profiles in H mode were reconstructed. By building up an integrated simulation platform for dynamic equilibrium configuration, and combining the rapid workflow processing method and experimental data with integrated simulation models, the ion and electron temperature, density, and current density profiles were obtained. The integration simulation platform was established to reconstruct the internal magnetic surface configuration, the plasma boundary parameter distribution, the ion/electron temperature, current density, and the <i>q</i> profile. The Ohmic current, bootstrap current, and radio-frequency current profiles with its fractions were calculated. The width of the pedestal region was about 7.52 cm according to our simulation results. It was found that the pressure gradient changes its direction at radial coordinate <i>ρ</i>(<i>r/a</i>) = 0.1 and reaches its maximum value near <i>ρ</i> = 0.7, which may be the internal transport barrier (ITB) configuration caused by negative shear. The profile reconstruction and real-time monitoring of the physical parameters are conducive to evaluating the quality of H mode discharge experiment and can assist in the steady-state operation of advanced operating modes such as HL-2M high normalized beta (<i>β<sub>n</sub></i>) discharge.

Adaptive Generalized Synchronization between Circuit and Computer Implementations of the Rössler System

The synchronization between chaotic systems implemented in similar ways—e.g., computer models or circuits—is a well-investigated topic. Nevertheless, in many practical applications, such as communication, identification, machine sensing, etc., synchronization between chaotic systems of different implementation types—e.g., between an analog circuit and computer model—might produce fruitful results. In this research, we study the synchronization between a circuit modeling the Rössler chaotic system and a computer model using the same system. The theoretical possibility of this kind of synchronization is proved, and experimental evidence of this phenomenon is given with special attention paid to the numerical methods for computer model simulation. We show that synchronization between a circuit with uncertain parameters and a computer model is possible, and the parameters obtained from the synchronized computer model are in high correspondence with the circuit element specification. The obtained results establish the possibility of using adaptive generalized synchronization for the parameter identification of real systems. It was also found that Heun’s method yielded the most accurate results in synchronization among second-order numerical integration methods. The best among the first-order methods appears to be the Euler–Cromer method, which can be of interest in embedded applications.

3D Reservoir Geological Modeling Algorithm Based on a Deep Feedforward Neural Network: A Case Study of the Delta Reservoir of Upper Urho Formation in the X Area of Karamay, Xinjiang, China

Three-dimensional (3D) reservoir geological modeling is an advanced reservoir characterization method, which runs through the exploration and the development process of oil and gas fields. Reservoir geological modeling is playing an increasingly significant role in determining the distribution, internal configuration, and quality of a reservoir as well. Conventional variogram-based methods such as statistical interpolation and reservoir geological modeling have difficulty characterizing complex reservoir geometries and heterogeneous reservoir properties. Taking advantage of deep feedforward neural networks (DFNNs) in nonlinear fitting, this paper compares the reservoir geological modeling results of different methods on the basis of an existing lithofacies model and seismic data from the X area of Karamay, Xinjiang, China. Adopted reservoir geological modeling methods include conventional sequential Gaussian simulation and DFNN-based reservoir geological modeling method. The constrained data in the experiment mainly include logging data, seismic attribute data, and lithofacies model. Then, based on the facies-controlled well-seismic combined reservoir geological modeling method, this paper explores the application of multioutput DFNN and transfer learning in reservoir geological modeling. The results show that the DFNN-based reservoir geological modeling results are closer to the actual model. In DFNN-based reservoir geological modeling, the facies control effect is obvious, and the simulation results have a higher coincidence rate in a test well experiment. The feasibility of applying multioutput DFNN and transfer learning in reservoir geological modeling provides solutions for further optimization methods, such as solving small-sample problems and improving the modeling efficiency.

Quantum-Based Creative Generation Method for a Dancing Robot.

In this paper, we propose a creative generation process model based on the quantum modeling simulation method. This model is mainly aimed at generating the running trajectory of a dancing robot and the execution plan of the dancing action. First, we used digital twin technology to establish data mapping between the robot and the computer simulation environment to realize intelligent controllability of the robot's trajectory and the dance movements described in this paper. Second, we conducted many experiments and carried out a lot of research into information retrieval, information fidelity, and result evaluation. We constructed a multilevel three-dimensional spatial quantum knowledge map (M-3DQKG) based on the coherence and entangled states of quantum modeling and simulation. Combined with dance videos, we used regions with convolutional neural networks (R-CNNs) to extract character bones and movement features to form a movement library. We used M-3DQKG to quickly retrieve information from the knowledge base, action library, and database, and then the system generated action models through a holistically nested edge detection (HED) network. The system then rendered scenes that matched the actions through generative adversarial networks (GANs). Finally, the scene and dance movements were integrated, and the creative generation process was completed. This paper also proposes the creativity generation coefficient as a means of evaluating the results of the creative process, combined with artificial brain electroenchalographic data to assist in evaluating the degree of agreement between creativity and needs. This paper aims to realize the automation and intelligence of the creative generation process and improve the creative generation effect and usability of dance movements. Experiments show that this paper has significantly improved the efficiency of knowledge retrieval and the accuracy of knowledge acquisition, and can generate unique and practical dance moves. The robot's trajectory is novel and changeable, and can meet the needs of dance performances in different scenes. The creative generation process of dancing robots combined with deep learning and quantum technology is a required field for future development, and could provide a considerable boost to the progress of human society.

STUDY OF INTERACTION OF AUTOMOTIVE AND RIVER TRANSPORT AT THE PORT TERMINAL BY THE METHOD OF SIMULATION

The aim of the study is to improve the technology of interaction between road and river transport on the territory of the port. The object of research is the port handling fronts; the subject of research is the technology of servicing various types of transport on the territory of the port terminal. Research methodology - simulation. The result of the study is an analytical assessment of the work of inland waterway transport for the carriage of goods, which indicates the absence of an integrated approach to improve the interaction of various modes of transport on the territory of the port terminal. Therefore, it is proposed to search for a rational technology based on simulation methods, which can reduce the time of non-production downtime. Competent organization of reloading from road to river transport and vice versa provides for the creation at the cargo terminal of such a traffic control system that provides collection and storage of operational information about the location of vehicles on the cargo fronts of the port terminal, the state of loading and unloading mechanisms, and allows making decisions on their use and transmitting commands to car drivers in order to improve the efficiency of interaction between road and river transport during cargo transshipment. For the proposed technology, the time for transshipment of cargo and idle time of vehicles under unloading was calculated using the theory of queuing systems. Counting the idle time of vehicles in various disciplines of choosing the cargo front (random or adjustable mode) made it possible to select the optimal system for regulating the approach of vehicles to the cargo fronts of the port terminal. The expected economic efficiency due to the reduction in the time of transshipment of goods from one mode of transport to another, according to the results of calculations, is 20,5 thousand EUR. The scientific novelty lies in the theoretical substantiation of various technologies for the interaction of road and river transport on the territory of the port terminal. At the same time, the problem of determining the optimal control system for the delivery of vehicles of the cargo fronts of the port terminal, on which reloading to river vessels occurs, has been formalized and solved using the methods of simulation modeling. This allows to reduce the downtime of transport units and more efficiently use the loading and unloading mechanisms, and, consequently, to reduce cost indicators. Practical significance: the proposed technology can be introduced into the technological processes of large river port terminals, where various types of transport interact. The simulation results are recommended to be used by the dispatcher staff when planning to bring vehicles to the berthing cargo fronts.

Modeling of flow and debris ejection in blasting erosion arc machining in end milling mode

Blasting erosion arc machining (BEAM) is a typical arc discharge machining technology that was developed around 2012 to improve the machinability of difficult-to-cut materials. End milling BEAM has been successfully developed and preliminarily applied in industry. However, owing to the high complexity of the flow field and the difficulty of observing debris in the discharge gap, studies of the flow and debris in end milling BEAM are limited. In this study, fluid dynamics simulations and particle tracking are used to investigate the flow characteristics and debris ejection processes in end milling BEAM. Firstly, the end milling BEAM mode is introduced. Then the numerical modeling parameters, geometric models, and simulation methods are presented in detail. Next, the flow distribution and debris ejection are described, analyzed, and discussed. The velocity and pressure distributions of the axial feed and radial feed are observed; the rotation speed and milling depth are found to have almost no effect on the flow velocity magnitude. Further, debris is ejected more rapidly in the radial feed than in the axial feed. The particle kinetic energy tends to increase with increasing milling depth, and smaller particles are more easily expelled from the flushing gap. This study attempts to reveal the flow field properties and debris ejection mechanism of end milling BEAM, which will be helpful in gaining a better understanding of BEAM.

Simulation and Analysis Methods for Stochastic Compartmental Epidemic Models

This article considers simulation and analysis of incidence data using stochastic compartmental models in well-mixed populations. Several simulation approaches are described and compared. Thereafter, we provide an overview of likelihood estimation for stochastic models. We apply one such method to a real-life outbreak data set and compare models assuming different kinds of stochasticity. We also give references for other publications where detailed information on this topic can be found.

Development of 340-GHz Transceiver Front End Based on GaAs Monolithic Integration Technology for THz Active Imaging Array

Frequency multipliers and mixers based on Schottky barrier diodes (SBDs) are widely used in terahertz (THz) imaging applications. However, they still face obstacles, such as poor performance consistency caused by discrete flip-chip diodes, as well as low efficiency and large receiving noise temperature. It is very hard to meet the requirement of multiple channels in THz imaging array. In order to solve this problem, 12-μm-thick gallium arsenide (GaAs) monolithic integrated technology was adopted. In the process, the diode chip shared the same GaAs substrate with the transmission line, and the diode’s pads were seamlessly connected to the transmission line without using silver glue. A three-dimensional (3D) electromagnetic (EM) model of the diode chip was established in Ansys High Frequency Structure Simulator (HFSS) to accurately characterize the parasitic parameters. Based on the model, by quantitatively analyzing the influence of the surface channel width and the diode anode junction area on the best efficiency, the final parameters and dimensions of the diode were further optimized and determined. Finally, three 0.34 THz triplers and subharmonic mixers (SHMs) were manufactured, assembled, and measured for demonstration, all of which comprised a waveguide housing, a GaAs circuit integrated with diodes, and other external connectors. Experimental results show that all the triplers and SHMs had great performance consistency. Typically, when the input power was 100 mW, the output power of the THz tripler was greater than 1 mW in the frequency range of 324 GHz to 352 GHz, and a peak efficiency of 6.8% was achieved at 338 GHz. The THz SHM exhibited quite a low double sideband (DSB) noise temperature of 900~1500 K and a DSB conversion loss of 6.9~9 dB over the frequency range of 325~352 GHz. It is indicated that the GaAs monolithic integrated process, diodes modeling, and circuits simulation method in this paper provide an effective way to design THz frequency multiplier and mixer circuits.

Study of driving dynamics of modular forestry tillage machine-tractor units in CAE SolidWorks Motion

The issues of simulation studies driving dynamics of wheeled forestry machine-tractor units on the surface with obstacles are considered. The method of simulation modeling in CAD SolidWorks and CAE SolidWorks Motion is used. A simplified 3d-model of the MTZ-82.1 agricultural wheeled tractor was created, preserving all the main geometric and mass-inertia parameters of the moving elements. The tractor model was equipped with front and rear mounted modular forest tillage implements in the transport position. The research was performed on a virtual track with four different types of obstacles similar to those found in forest conditions. In a computer experiment, three different schemes of units were studied and the following parameters were obtained: wheel lift height, lateral displacement of the center of gravity, and linear speed fluctuations. Analysis of the results showed that the 0+1 scheme (rear-mounted single-row harrow) was the most stable. The heaviest scheme 1+2 (front-mounted drum chopper and rear-mounted two-row harrow) also had satisfactory stability. The least stable was a tractor equipped according to the 0+2 scheme (rear-mounted two-row harrow). The virtual experiment allowed us to study the dynamic stability of various forestry units in the transport position and establish the most stable configurations.

Method of simulation modeling and computing analysis for tube bending

Simulation of thin-walled tube bending process not only results in a large amount of calculation due to its high nonlinearity, but also leads to its non-uniqueness in simulation modeling because of the particularity and diversity of the mandrel structure. The paper proposes a method for the simulation analysis of molding process of tube bends, which combines coordinate translation with mass scaling and is called the equivalent method, and gives out super-elastic mandrel model describing working state of mandrel more reasonable. It deduces the basic formula of the equivalent method which takes transformation of time coordinate, meanwhile keeps spatial coordinates not transform, and controls the calculation amount by controlling the time of banding molding and time step of recursive solving. It validates correctness and validity of the equivalent method and the mandrel model, which shows that the super-elastic mandrel models could avoid blindness, and the equivalent method greatly raises the simulation efficiency, and has enough analysis precision.

A Method of Simulation Modeling of Chemmotological Processes for Determining and Predicting Performance Properties of Fuels and Lubricants

This paper presents a chemmotological process modeling method which, based on the results of fuels and lubricants (FL) tests on physical models of FL using objects, enables computer construction of mathematical and simulation models of the processes and use of them for evaluating and predicting the performance properties of FL’s with due regard for the probability characteristics (distribution laws) of the FL composition and the actual modes and conditions of operation of the equipment. The results of approbation of the method, as applied to motor fuel properties, are presented.

SIMULATION MODELLING DEVELOPMENT IN DESIGN OF ENERGY EFFICIENCY IMPROVEMENT OF ARCHITECTURAL SOLUTIONS

The article deals with the methods of using and improving the work of the simulation modelling method in architectural design. As a result, the authors have tried to optimize their work with criteria such as energy demand, environmental impact, geometry, and materials. The rational use algorithm of these software products in the integrated design of energy efficiency improvement of buildings, complexes and urban structures have been proposed

A Model to Control the Formation of Multi-Component Charge Portions on a Blast Furnace Conveyor

Introduction. Bell-less tops used in the charging area give significantly wider opportunities for regulating and distributing the charge material along the furnace top radius. Moreover, it becomes feasible to develop the methods for gas flow control and these methods shall differ from the conventional ones. One of such methods is introduction of multi-component portions of the charge with a technology based component ratio. Problem Statement. The bell-less top charging device is not designed for that type of portioning when the charge material mixing is accompanied with a simultaneous shift of one component with respect to other one for a certain set value, while charging. These portions can be formed with the use of computer-aided stock-conveying system, while discharging the material from weighing hoppers into the blast furnace conveyor. Purpose. This research aims at the development of the structure, the functioning algorithms and the mathematical model for the system to control the formation of multi-component mixed charge batches in order to increase the blast furnace productivity and to reduce the specific coke consumption. Materials and Methods. In this research, the methods of automatic control theory and artificial intellect for the synthesis of weight neuro-fuzzy controllers within the automatic control system of charge dosage have been used. The developed system designed to control multi-component charge portioning via PC has been tested by means of simulation modelling methods. Results. There has been developed an algorithm for operating the system for controlling the multi-component mixed charge preparation on the conveyor, given the arrangement of the specified components, their ratios in portions, total volumetric productivity of the conveyor, the variable geometry of the unloaded material, in the connection with the on-line information on the mixing process. The feasibility of the system has been verified by its simulation with the use of standard application tools. Conclusions. It has been established that the designed control system allows the formation of mixed portions of any composition defined by an operator at a given maximum output of the conveyor and prevents its overload in terms of mass or volume.

Modeling the process of assessing the efficiency and development of production activities of the passenger fleet in different operating conditions

The object of research is the efficiency of production activities of the passenger fleet. Assessment of the production capacity of the passenger fleet is one of the most important stages for modelling the options for its functioning and development, the process of which is currently insufficiently studied.The functioning of the passenger fleet is influenced by such factors as the size of passenger traffic, the technical condition of ships, the level of organization of the technical and commercial operation of the fleet, methods of forming tariffs for transportation and the cost of cruises, navigation conditions, seasonality, economic and political situation in the region of operation of the fleet. It is proposed to use the indicator of the financial result and the carrying capacity of the fleet as the main indicators of the efficiency of the passenger fleet. Using the method of simulation modelling, the process of assessing the efficiency of the functioning of the passenger fleet in various operating conditions is characterized.It is determined that provided that the passenger traffic on the routes under consideration (linear and cruise) is fully developed and there is a reserve of the fleet’s carrying capacity, it is advisable for the ship-owner to master new routes. As a result of solving an economic and mathematical model for the optimal distribution of ships along existing and new routes, it becomes possible to make a decision on attracting an additional fleet on lease terms to increase the carrying capacity of the fleet. To assess the effectiveness of the functioning of our own and leased fleets, it is advisable to use an economic and mathematical model of the optimal distribution of the aggregates of the fleet – our own, leased and competitors. As a result of solving the problem, it is possible to conclude about the efficiency of the fleet and the need for modernization.The proposed simulation model takes into account the performance of the tasks facing the ship-owner. On the one hand, this is an increase in the profit of the ship-owner, on the other, full satisfaction of the needs of passengers and tourists in water transport services due to the efficient use of the carrying capacity of the fleet in various operating conditions. This also allows the ship-owner to make decisions on the further development of production activities

Simulation Modeling As a Tool of Decision Support During Reorganization of the Diagnostic Department of a Multidisciplinary Hospital

Abstract Steadily growing flow of patients and a constant increase in the requirements for the quality of medical care more and more often lead to the need to reorganize the work of various departments of medical hospitals. However, such actions are very costly and do not always give the desired result. One of the effective methods of preliminary planning, as well as predicting the results of proposed transformations, is the method of simulation modeling of medical and diagnostic processes based on a specially created model. In this article we describe the original data on the operation of the admission and diagnostics department (ADD) of N.V. Sklifosovsky Institute, which served as one of the grounds for its reorganization, as well as the creation of a simulation model of ADD, reconstructed on the principles of a patient-oriented approach. We considered all stages of the model construction in detail and thereby justified its structure and the qualitative and quantitative parameters which formed the basis therein. The temporal and numerical results of modeling the flow of patients through the ADD, as well as the flow of changes in the parameters of the model to the throughput of the ADD are presented. Thus, specific examples show how problem areas of the existing diagnostic and treatment process can be identified, and what options are available for its optimization and modernization. In addition, suggestions are made for further improvement of the created model and options for its use, for example, for the study of various contingencies and emergencies, mass revenues, etc.