SIMULTECH 2019 Abstracts

Area 1 - Simulation Tools and Platforms
Full Papers Short Papers
Area 2 - Formal Methods
Full Papers Short Papers
Area 3 - Complex Systems Modeling and Simulation
Full Papers Short Papers
Area 4 - Application Domains
Full Papers Short Papers

Area 1 - Simulation Tools and Platforms

Full Papers
Paper Nr: 15
Title:

HintCO – Hint-based Configuration of Co-simulations
Authors:

Cláudio Gomes, Bentley J. Oakes, Mehrdad Moradi, Alejandro T. Gámiz, Juan C. Mendo, Joachim Denil, Hans Vangheluwe and Stefan Dutré
Abstract: Simulation-based analyses of Cyber-Physical Systems are fundamental in industrial design and testing approaches. The utility of analyses relies on the correct configuration of the simulation tools, which can be highly complicated. System engineers can normally judge the results, and either evaluate multiple simulation algorithms, or change the models. However, this is not possible in a co-simulation approach. Co-simulation is a technique to perform full-system simulation, by combining multiple black-box simulators, each responsible for a part of the system. In this paper, we demonstrate the difficulty of correctly configuring a co-simulation scenario using an industrial case study. We propose an approach to tackle this challenge by allowing multiple engineers, specialized in different domains, to encode some of their experience in the form of hints. These hints, together with state-of-the-art best practices, are then used to semi-automatically guide the configuration process of the co-simulation. We report the application of this approach to a use case proposed by our industrial partners, and discuss some of the lessons learned.
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Paper Nr: 31
Title:

Active Learning Program Supported by Online Simulation Applet in Engineering Education
Authors:

D. Valiente, L. Payá, S. Fernández de Ávila, J. C. Ferrer, S. Cebollada and O. Reinoso
Abstract: Nowadays education programs in engineering degrees have evolved towards advanced learning models and methodologies, which are either partially or entirely sustained by ICT (Information, Communication, and Technology) resources, and blended approaches. In this sense, electronics courses have become of paramount importance in most education plans within engineering degrees at university. Therefore the adaption to such novel methodologies is increasingly demanded. According to this, we propose an improved teaching program concentrated on the use of an online simulation tool, amongst other digital resources. The program is addressed to students in first levels of engineering degrees, within the framework of the Spanish public university system. In particular, the methodology has been devised through the use of an online circuit simulation applet in Java, which does not require any software installation. The main purpose is to enhance the general achievement of the students, particularizing on their practical competences, digital skills, engagement and motivation towards the learning of electronics, sustained by digital resources such as simulation. A population of 258 students enrolled during the academic year 2017/2018 has been established as a sample for presenting achievement results, surveys data and comparison statistics with other digital resources. Additionally, test groups of roughly 50% out of the total population of students have been established in order to confirm the success of the approach, in contrast to the former teaching methodology. As a result, the approach proves to be an active model which allows the students to develop long-term and autonomous skills in electronics and simulation.
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Paper Nr: 32
Title:

Computational Fluid Dynamics Model for Sensitivity Analysis and Design of Flow Conditioners
Authors:

V. Askari, D. Nicolas, M. Edralin and C. Jang
Abstract: Flow conditioners are used to measure flow rate more accurately. The sensitivity of flow measurement devices to swirling flows and not fully developed flows are subjects of concerns to flowmeter manufacturers as well as industries. Inaccurate flow measurement occurs in the presence of swirl flow and when the flow velocity profile is not fully developed. Distorted profiles occur when the piping configuration upstream of the flow measurement devices changes. Certain length of straight piping upstream of a flow meter is required to achieve acceptable flow velocity profile for expected flow meter accuracy. In some installations, it is not realistic to run lengths of piping to reach an acceptable flow velocity profile. Introducing flow conditioners into the system reduces piping needed to reach fully developed flow and significantly weaken swirling flows. In this study, a Computational Fluid Dynamics (CFD) model is developed and validated which is used to investigate systematically the sensitivity of various parameters for perforated flow conditioners. Published data and an experimental setup was used to verify the CFD model.
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Paper Nr: 52
Title:

IFOSMONDI: A Generic Co-simulation Approach Combining Iterative Methods for Coupling Constraints and Polynomial Interpolation for Interfaces Smoothness
Authors:

Yohan Éguillon, Bruno Lacabanne and Damien Tromeur-Dervout
Abstract: This paper introduces IFOSMONDI co-simulation algorithm that combines iterative coupling methods and a smooth representation of interface variables. In explicit (i.e. non-iterative) coupling methods, representing smooth interface variables requires the introduction of a delay (Busch, 2016) because the values of the interface variables at the end of a given macro-step are not known when the co-simulation only reached the beginning of this very macro-step. One of the advantages of implicit co-simulation (i.e. iterative coupling methods) is that the values of the interface variables can be known at the end of a macro-step with the possibility to replay the integration on this very macro-step. Combining this with a polynomial representation of the interface variables enables to use interpolation instead of extrapolation across the macro-steps (Kübler and Schiehlen, 2000). Taking into account time-derivatives of interface variables makes it possible to ensure C1 smoothness even with no history of the past exchanged data: then, no delay is introduced. A new possibility then arises: the solvers of each subsystem may take into account this smoothness and be less restrictive on their restarts due to the communication times. The results obtained on the test case of the two mass oscillators (Busch, 2016) show the advantage of IFOSMONDI coupling in terms of trade-off between elapsed time and accuracy.
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Short Papers
Paper Nr: 4
Title:

Branching Poisson Process Modelling for Reliability Analysis of Repairable Mechanical System
Authors:

Nicolas L. Roche-Carrier, Guyh D. Ngoma, Yasar Kocaefe and Fouad Erchiqui
Abstract: In a series of mechanical system maintenance it is possible to observe failures, sometimes intermittent, which cause series of unsuccessful repair attempts before the correct fault is detected and the repair is effective. Unsuccessful repairs performed for the same failure are not negligible and must be taken into account for the reliability analysis. To solve this type of problem, the model proposed is the branching Poisson process (BPP). This process is the representation of a primary failure that triggers one or more subsidiary failures. A summary and an adaptation for the resolution of the branching Poisson with failures time of repairable mechanical system were highlighted including some clarification regarding the steps of resolution implemented.
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Paper Nr: 24
Title:

Scenario-based Testing of ADAS - Integration of the Open Simulation Interface into Co-simulation for Function Validation
Authors:

Nadja Marko, Jonas Ruebsam, Andreas Biehn and Hannes Schneider
Abstract: Testing Advanced Driver Assistance Systems (ADAS) is challenging, as the environmental conditions that appear in reality are manifold and complex. Testing only on the road is not feasible since it is expensive and difficult to reproduce results. Additional virtual tests based on environment simulations are therefore required. These simulations are based on scenarios representing real world situations that provide ground truth data to sensors or sensor models for the environmental perception. To integrate environment simulations with function simulations, object lists and sensor raw data need to be exchanged and have to be processed by the function under test. Various simulators for automated driving exist that provide different, not uniquely defined interfaces. The Open Simulation Interface (OSI) is a specification that describes a generic interface for the environmental perception of automated driving functions. In this paper, we describe a co-simulation framework in which OSI is applied for testing an ADAS. The co-simulation framework is based on generic, standardized interfaces and uses existing tools that we extended with OSI to couple environment simulations with function simulations. With a realistic co-simulation setup, that have been defined by industry partners, we tested the applicability of OSI and describe the results here.
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Paper Nr: 42
Title:

Using a Hybrid Simulation Model to Maximize Patient Throughput of Magnetic Resonance Imaging in a Medical Center
Authors:

Li-Hui Lee, Yang-Yu Ou, Yu-Ting Cheng, Ying-Chou Sun, Hsiu-Mei Wu and Wan-You Guo
Abstract: The purpose of this study is to shorten the waiting time of a patient to undergo a magnetic resonance imaging (MRI) examination as well as to increase the utilization rates of the five MRI scanners in a 2,735-bed medical center of Taiwan. We simulate the current MRI examination workflow through a hybrid simulation model, consisting of discrete event and agent-based simulations. Then, we maximize the MRI patient throughput per day with more radiographers during current business hours. For reasons of feasibility, a cost-effectiveness analysis is also conducted. AnyLogic, Excel, and SAS were used for building the simulation models and conducting the statistical analysis. The results show that providing 248 additional patient examinations with one additional radiographer employed during the 11:00 to 19:00 time frame would shorten the waiting time of a patient to undergo an MRI examination by 2.51 days, increase the utilization rate of each MRI scanner by an average of 6.15%, and bring an additional gross income of US$38,424 to US$69,169 per 31-day month.
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Paper Nr: 50
Title:

Research and Development of High Performance Finite Element for Large Scale Acoustic Analysis Method
Authors:

E. Takaoka, Y. Murakami and A. Takei
Abstract: In recent years, numerical methods such as the finite element method are developed for sound field prediction of architectural spaces. However, large-scale analysis is often necessary because of the larger domains and the higher frequencies that we deal with in engineering applications. Therefore, we often only consider larger domains at low frequencies or high frequencies in smaller domains. In this paper, the iterative domain decomposition method (IDDM) is applied to solve transient and steady-state acoustic problems. By applying the IDDM, the effectiveness of the large-scale acoustic analysis can be shown. In addition, the results of introducing high-order elements into the analysis are shown.
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Paper Nr: 54
Title:

A Simulator for Drones and FANET Management Supporting Multimedia Traffic under Human Mobility
Authors:

M. Tropea, F. De Rango and P. Fazio
Abstract: In this paper a simulator for the management of a team of Unmanned Aerial Vehicles (UAVs) and drones has been proposed. This new network is known as Fly Ad-Hoc Network (FANET), and it is a particular type of Mobile Ad-Hoc Network (MANET) but with some specific aspects that allow to provide new services in future generation networks. One of the possible applications is emergency situations or scenario where drones can provide an additional or complementary access networks supporting web services and multimedia traffic. In this paper a simulator for FANET deploying has been proposed providing the possibility to simulate different scenarios with different coverage areas. New coverage model has been included in the features and also interesting human mobility model to support more realistic users mobility. Moreover, additional modules for traffic pattern generation have been implemented to create scenario where mobile users can activate multimedia calls and traffic on FANET. Some simulations have been led out to show how the simulator works.
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Paper Nr: 58
Title:

Deeplearning Convolutional Neural Network based QoE Assessment Module for 4K UHD Video Streaming
Authors:

Akm Ashiquzzaman, Sung M. Oh, Dongsu Lee, Hoehyeong Jung, Tai-won Um and Jinsul Kim
Abstract: With the rapid development of modern high resolution video streaming services, providing high Quality of Experience (QoE) has become a crucial service for any media streaming platforms. Most often it is necessary of provide the QoE with NR-IQA, which is a daunting task for any present network system for it’s huge computational overloads and often inaccurate results. So in this research paper a new type of this NR-IQA was proposed that resolves these issues. In this work we have described a deep-learning based Convolutional Neural Network (CNN) to accurately predict image quality without a reference image. This model processes the RAW RGB pixel images as input, the CNN works in the spatial domain without using any hand-crafted or derived features that are employed by most previous methods. The proposed CNN is utilized to classify all images in a MOS category. This approach achieves state of the art performance on the KoniQ-10k dataset and shows excellent generalization ability in classifying proper images into proper category. Detailed processing on images with data augmentation revealed the high quality estimation and classifying ability of our CNN, which is a novel system by far in these field.
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Paper Nr: 60
Title:

A Comparison of A* and RRT* Algorithms with Dynamic and Real Time Constraint Scenarios for Mobile Robots
Authors:

João Braun, Thadeu Brito, José Lima, Paulo Costa, Pedro Costa and Alberto Nakano
Abstract: There is an increasing number of mobile robot applications. The demanding of the Industry 4.0 pushes the robotic areas in the direction of the decision. The autonomous robots should actually decide the path according to the dynamic environment. In some cases, time requirements must also be attended and require fast path planning methods. This paper addresses a comparison between well-known path planning methods using a realistic simulator that handles the dynamic properties of robot models including sensors. The methodology is implemented in SimTwo that allows to compare the A* and RRT* algorithms in different scenarios with dynamic and real time constraint scenarios.
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Paper Nr: 61
Title:

A Two-phased Risk Management Framework Targeting SMEs Project Portfolios
Authors:

Christophe Ponsard, Fabian Germeau, Gustavo Ospina, Jan Bitter, Hendrik Mende, René Vossen and Robert H. Schmitt
Abstract: Managing project risks is challenging for many enterprises, especially smaller ones, because they generally only have very limited method or tool support, i.e. basic, qualitative and rather short term reaction to the occurrence of risks. This results in higher vulnerability and reduced competitiveness. This paper proposes a risk management framework fitting SMEs needs by providing a way to adequately quantify risks and address them at two levels. First, an Analytical Hierarchy Process (AHP) is used to perform cost-benefit analyses of the possible mitigation actions assessed through Monte-Carlo simulations. Second, an on-line optimisation tool is used to make sure the planning is following the minimal risk path and reschedule mitigation action as soon as a risk has materialised. To address the limited SMEs resources, the core components are provided as Open Source with a clean application programming interface for easing integration with existing tools. A reference integration with the Open Source Redmine project management tool is also provided.
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Paper Nr: 63
Title:

A Simulation Approach based Project Schedule Assessment
Authors:

Ruiping Wang, Xu Li, Xiao Song, Lei Dai and Yixin Li
Abstract: Traditional program evaluation and review technique lacks of complex task relation models. To tackle this, this paper proposes a project schedule risk assessment model based on extended Petri net, in which the characteristics of task duration, task overlap and sub-tasks are modelled. Based on the characteristics of concurrent iteration in product development schedule, the influence of each sub-task relationship on the simulation uncertainty is considered. In this case, several mathematical distributions are used to simulate the schedule of the subtask based on its own characteristics and the relationship between them. Based on the above modelling, the key path of the project schedule is selected, and the transition mechanism of state change in the simulation is designed. Finally, simulation results show that the proposed project schedule risk assessment method can provide specific reference for the development plan of the whole project and its sub-projects. In addition, the model can also be used to evaluate the cost of the project and establish the cost standard of the project according to the evaluation.
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Paper Nr: 37
Title:

Modelling, Optimization, and Simulation of Several First Aids in an Area with Plant Simulation
Authors:

Jolana Sebestyénová and Peter Kurdel
Abstract: Plant Simulation software comprises all the features needed to model the functional aspects of most real-world systems. Specification of complex optimization problem (in sense of many optimization parameters) and its solving in Plant Simulation by genetic algorithm is possible, but it leads to significantly ascending simulation time. The paper presents division of the optimization to two parts: first part of the optimization via GA using distributed computing, and the second part of optimization parameters that will be used in the second stage of the optimization. Modelling, optimization, and simulation procedure proposed for Plant Simulation is presented and tested on a simple use case. In the first stage, the placement of several first aid posts in the area where distinct happenings can go on is optimized, the second stage of the optimization is done using Experiment manager with the aim to select the best solution, i.e. optimal number of first aids in the area depending on additional optimization parameters.
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Paper Nr: 38
Title:

Modeling and Simulation of the Hospital-at-Home Service Admission Process
Authors:

Ilaria A. Amantea, Marzia Arnone, Antonio Di Leva, Emilio Sulis, Dario Bianca, Enrico Brunetti and Renata Marinello
Abstract: This article focuses on the analysis of the admissions to hospital-at-home service within the framework of Business Process Management. While traditional process analysis deal with internal hospital services, having a particular and specific scenario, e.g. a ward of an hospital, here we investigate a quite innovative service with a strong socio-territorial impact based on real data. In particular, we are interested in the understanding of the selection process in which staff discriminate cases of interest for the service. We describe here our methodological framework combining data and event log analysis, modeling with standard language and business process simulation with scenario analysis.
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Paper Nr: 41
Title:

Evaluation of Driving Efficiency and Safety with a Custom-Developed Simulation Scenario
Authors:

David González-Ortega, Francisco J. Díaz-Pernas, Mario Martínez-Zarzuela and Míriam Antón-Rodríguez
Abstract: In this paper, we present a custom-developed driving simulation scenario and a vehicle model developed to evaluate driving efficiency and safety. The scenario includes different road sections, traffic conditions, and events, including a through road similar to a real road section in the city of Valladolid (Spain). The modeled vehicle is an ICE vehicle with manual or automatic gear shift. During a simulation, following a guided or a free route, the speed, rpm, gear, consumption, and traffic offences are showed in real time and stored in files for further processing. Six people drove in the scenario twice, one time with automatic gear shift and another with manual gear shift. An analysis of the results has been carried out to know the factors with influence on driving efficiency and safety. A significant relation between efficient and safe driving was found. People that took part in the experiments ranked the simulation scenario positively regarding ease of interaction, realistic experience, usefulness for driving learning, and entertainment capacity.
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Paper Nr: 45
Title:

Thermodynamic Study of Improving Efficiency of a Gas Turbine Locomotive
Authors:

Ilia Krupenich, Andrey Tkachenko and Evgeny Filinov
Abstract: Although railroad electrification has multiple benefits and is one of the global initiatives to promote transportation sustainability, 50% of the railroads are still off the electrical grid. Use of the gas turbine as a source of mobile electricity is one of the promising technologies, crucial for the transition to electrical traction. This paper is a part of the project of PSC KUZNETSOV on developing the gas turbine locomotive. Current issues include low performance and resulting high exhaust temperature. These issues are because of high hydraulic losses due to the limited roof area used for the air intake. Aim of this work is to find optimal thermodynamic operation point which provides efficiency boost, lower exhaust temperature and requires least alterations to the design. This data will be the basis for the next stages of development, including optimization of the turbomachines and structural design for strength improvement. This study used the numerical simulation of the thermodynamic behavior of the gas turbine power plant. Firstly, the virtual model of the engine was developed using the CAE-system ASTRA and the parameters of the engine provided by the PSC KUZNETSOV. Secondly, model adequacy was assured using the experimental data on climatic characteristics of the gas turbine power plant. The third step was to investigate how would removing the first one, two or three stages of the low-pressure compressor alter its characteristics, and the performance of the engine. Altered low-pressure compressor (LPC) required adjustments of the operating points of all turbines, so this issue was addressed at the next step. Finally, the thermodynamic characteristics of the power plant were calculated using the optimized compressor (three- and four-stage variants) and turbine. Optimization aimed at keeping target performance indicators while providing lower air flow rate and decreased exhaust temperature. It also included restrictions on the rotational speeds, geometry and other parameters to keep the stress-strain state of the engine elements close to the baseline. The results of this research show two promising solutions for the 6MW and 8.3MW variants of the power plant having air flow rates 27 and 17 percent lower than the baseline, respectively. The results of this study would be used to design the altered engine components: optimize blade geometry and strength of the critical elements of the engine.
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Paper Nr: 46
Title:

Improved Model for Small-scale Turbofan Engine Weight Estimation
Authors:

Evgeny Filinov and Yaroslav Ostapyuk
Abstract: Weight estimation plays a crucial role at the initial stages of gas turbine development. A number of weight estimation models are described in the open sources, but design data available at these stages is scarce, so these models tend to have low accuracy. This study examines the features of available models and proposes improved weight estimation model. The database of the existing 50 turbofans with thrust lower than 50kN was developed to compare models with the statistical information, and to update the regression coefficients of the proposed model. Standard deviations and correlation factors of models were determined. Refining of model coefficients was obtained as a result of minimization of a standard deviation value.
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Area 2 - Formal Methods

Full Papers
Paper Nr: 7
Title:

Development and Validation of Active Roll Control based on Actor-critic Neural Network Reinforcement Learning
Authors:

Matthias Bahr, Sebastian Reicherts, Philipp M. Sieberg, Luca Morss and Dieter Schramm
Abstract: This paper deals with the application of machine learning for active roll control of motor vehicles. For this purpose, a special learning method based on reinforcement learning with an actor-critic model is used. It discusses and elaborates the basic design of the neural controller and its optimization for a fast and stable training. The methods mentioned are then validated. Both the training and the validation data are simulatively generated with the software environments MATLAB / Simulink and IPG CarMaker, while the architecture and training of the artificial neural network used is realized with the framework TensorFlow.
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Paper Nr: 18
Title:

Optimal Trigger Sequence for Non-iterative Co-simulation
Authors:

Franz R. Holzinger and Martin Benedikt
Abstract: An execution sequence approach of interacting subsystem is presented for non-iterative co-simulation frameworks. Local behaviour of coupling signals and subsystems are used to describe a general optimization problem of co-simulation. Therefore the linking matrix is weighted by analysis of the coupling signals within fuzzy integrated expert knowledge. The weighted linking matrix is transferred to a directed co-simulation graph, which can be interpreted as an appropriate travelling sales man problem. The solution of this co-simulation graph provides an optimized trigger sequence of the subsystems.
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Paper Nr: 30
Title:

A Simplified Finite Element Analysis Method for Axial Compression Behavior of Rectangular Concrete Columns with Interlocking Multi-spiral Reinforcements
Authors:

Ping-Hsiung Wang and Kuo-Chun Chang
Abstract: This paper proposes a simplified finite element analysis method to analyze the axial compression behavior of rectangular concrete columns confined by interlocking multi-spiral reinforcements. The proposed method utilizes an elastic finite element analysis to approximate the distribution and ultimate state of confining stress in each core concrete element, which is substituted into the Mander confined concrete model to obtain the integrated compressive curve of a column. Verification of the proposed method against the test results of four 4-spiral and four 5-spiral reinforcement columns shows good agreement. Parametric studies focused on the 5-spiral reinforcement show that for the same amount of transverse reinforcement, a column with a larger confined area, which closely depends on the radius ratio between the small and large spirals (r_s/r_b), can receive a better axial load-carrying capacity and confinement efficiency. To achieve economic confinement design, the volumetric ratio of large spirals to small spirals (ρ_s/ρ_b) to have the concurrent yielding of both large and small spirals was found to be around 1.0, 0.8, and 0.7 for r_s/r_b= 1/2, 1/3, and 1/4, respectively.
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Paper Nr: 33
Title:

Middle Point Reduction of the Chain-recurrent Set
Authors:

Carlos Argáez, Peter Giesl and Sigurdur F. Hafstein
Abstract: Describing dynamical systems requires capability to isolate periodic behaviour. In Lyapunov’s theory, the qualitative behaviour of a dynamical system given by a differential equation can be described by a scalar function that decreases along solutions: the Complete Lyapunov Function. The chain-recurrent set will produce constant values of an associated complete Lyapunov function and zero values of its orbital derivative. Recently, we have managed to isolate the chain-recurrent set of different dynamical systems in 2- and 3-di- mensions. An overestimation, however, is always obtained. In this paper, we present a method to reduce such overestimation based on geometrical middle points for 2-dimensional systems.
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Paper Nr: 40
Title:

A Social Network Model for Integration of Refugees
Authors:

Fabio Curi, Dimitris Nikolopoulos and Eric M. Araújo
Abstract: The present work aims to study and model the integration of refugees who appear in a society, through the implementation of adaptive social networks. In our model, for each individual, their characteristics of religiousness and language skills are considered for the social integration. We also explore the homophily phenomenon as part of the creation of new connections and the changes on the refugees’ traits. As it most commonly happens in real life, refugees appear in a community-structured social network as individual nodes without any connection, and interactions between refugees and non-refugees are built through a defined methodology which applies local search, random attachment and node deletion. We show a few case scenarios and perform a social network analysis.
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Short Papers
Paper Nr: 43
Title:

Modeling Dynamic Processes with Deep Neural Networks: A Case Study with a Gas-fired Absorption Heat Pump
Authors:

Jens Lippel, Martin Becker and Thomas Zielke
Abstract: Deriving mathematical models for the simulation of dynamic processes is costly and time-consuming. This paper examines the possibilities of deep neural networks (DNNs) as a means to facilitate and accelerate this step in development. DNNs are machine learning models that have become a state-of-the-art solution to a wide range of data analysis and pattern recognition tasks. Unlike mathematical modeling approaches, DNN approaches require little to no domain-specific knowledge. Given a sufficient amount of data, a model of the complex nonlinear input-to-output relations of a dynamic system can be learned autonomously. To validate this DNN based modeling approach, we use the example of a gas-fired absorption heat pump. The DNN is learned based on several measurement series recorded during a hardware-in-the-loop (HiL) simulation of the heat pump. A mathematical reference model of the heat pump that was tested in the same HiL environment is used for a comparison of a mathematical and a DNN based modeling approach. Our results show that DNNs can yield models that are comparable to the reference model. The presented methodology covers the data preprocessing, the learning of the models and their validation. It can be easily transferred to more complex dynamic processes.
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Area 3 - Complex Systems Modeling and Simulation

Full Papers
Paper Nr: 5
Title:

Dynamic Modeling and Simulation of a Slurry Mixing and Pumping Process: An Industrial Case
Authors:

Ridouane Oulhiq, Khalid Benjelloun, Maarouf Saad, Yassine Kali and Laurent Deshayes
Abstract: In this paper, a dynamic model of a slurry mixing and pumping process is proposed. The centrifugal pump is modeled based on the hydraulic application, the hydraulic part and the induction motor models, taking into account the pumped slurry density. This paper also proposes a new approach to estimate the parameters of the pump’s hydraulic part model based on the pump characteristic curves. Additionally, a dynamic simulation of the system is realized under MATLAB/Simulink environment and the variation effect of the process inputs on the outputs is studied.
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Paper Nr: 17
Title:

Modeling and Discretization of Hydraulic Actuated Telescopic Boom System in Port-Hamiltonian Formulation
Authors:

Lingchong Gao, Wang Mei, Michael Kleeberger, Haijun Peng and Johannes Fottner
Abstract: The hydraulic actuated telescopic boom system is the primary operation actuator of mobile cranes and aerial platform vehicles. The purpose of this paper is to develope a unified mathematic model of such a boom system which is a multi-domain system consisting of boom structure and hydraulic drive system. The model is formulated within the port-Hamilton (PH) formalism using the definition of hydraulic system and elastic boom structure as (Stokes-) Dirac structures. The Port-Hamiltonian systems can be easily interconnected thus allowing the description of a complex system as a composition of subsystems. This property is especially useful to model a multi-domain system with energy exchanges between subsystems. Considering the boom structure as a Timoshenko beam, the luffing operation of boom system is simplified in a plane coordinate system. The Port-Hamiltonian model of the hydraulic system and the boom structure are described with details separately, a structure-preserving discretization is applied to transfer the distributed-parameter boom model into a lumped-parameter model. Then the interconnections between the subsystems are illustrated and a complete simulation including hydraulic system is accomplished in MATLAB/Simulink.
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Paper Nr: 21
Title:

Reducing the Hydraulic Resistance in the Inlet Device of the Gas Turbine Unit
Authors:

Oleg Baturin, Daria Kolmakova, Grigorii Popov, Vasilii Zubanov and Yulia Novikova
Abstract: The paper presents the results of numerical simulation of air flow through a modernized variant of the inlet filter unit (IFU) of the gas compressor unit GPA-Ts-16. A feature of the IFU design is that to reduce the load on the filter unit, it is proposed to be as compact as possible, which determines its complex shape. The goal of the study is to study the hydraulic losses and to develop the measures to reduce them, since it is found that every 100 Pa of losses in the inlet unit increases the consumption of fuel gas by 2.5 kg/h or reduces the engine power by 10.5 kW. Calculations of hydraulic losses in IFU are carried out for cases of absence or presence of wind with a velocity from 0 to 35 m/s, blowing from 5 main directions (0º, 45º, 90º, 135º, 180º). Studies are also carried out on the effect of the weather shield shape, presence of baffles under it, and the rack in the shaft on the hydraulic losses. As a result of the research, recommendations are provided for designing (changing the shape) of the inlet filter unit that eventually allow to propose a design that will reduce the hydraulic losses in IFU by 15% relative to the originally suggested variant.
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Paper Nr: 23
Title:

Multi-level "Learnable" Model of the Workflow in the Centrifugal Compressor Stage
Authors:

Evgeny Marchukov, Igor Egorov, Oleg Baturin, Grigorii Popov and Andrei Volkov
Abstract: The paper presents the main ideas of the virtual test bench concept for rapid obtaining of the reliable characteristics of compressors based on a multi-level mathematical model with a two-step identification using data obtained from mathematical models with a high order of accuracy. One of the possible identification algorithms and the results of its successful testing are given on the example of a centrifugal compressor stage developed and tested at NASA. The authors created a pilot version of a digital analogue of a centrifugal compressor. Its main feature is that it is created based on a multi-level mathematical model with a two-step identification by the data obtained from mathematical models with a high order of accuracy.
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Paper Nr: 35
Title:

A Species-specific Individual-based Simulation Model of Mixed Mangrove Forest Stands
Authors:

Ian Estacio, Khristoffer R. Quinton, Edgardo Macatulad and Severino Salmo
Abstract: A species-specific spatially explicit individual-based model has been developed to simulate the development of mixed mangrove forest stands featuring eight species. The model is a forest stand model that forecasts mangrove forest development in a 50 m x 50 m plot by simulating the recruitment, growth, and mortality of individual mangrove trees. Species-specific growth rates, shade responses, and salinity responses of each species were incorporated to observe differences in forest structure given different salinity conditions. The model used a modified Field of Neighborhood (FON) approach that considers species-specific responses to shading and a salinity response function that considers the species-specific salinity upper boundary value of optimum growth and maximum porewater salinity of a mangrove. Simulation results of 300 years given salinity conditions in a specific site in Katunggan It Ibajay (KII) showed matching dominant species in the site. Simulation results of 500 years given extreme low and high salinity values showed consistent forest dynamics where above-ground biomass and tree count approach certain limit values as the forest stand matures. Simulation results also of 300 years given salinity values ranging from 1 – 37 ppt showed the different dominant species for different salinity conditions.
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Short Papers
Paper Nr: 2
Title:

Turbulent Flow Modelling of a Jet in a Cross-Flow Stream: Model and App
Authors:

M. Tabatabaian
Abstract: The flow of a jet stream entering a cross flow main stream is modelled along with introducing the related App. The turbulent flow details are computed and validated against similar computational and experimental results. For example, dimensionless streamwise and cross-streamwise velocity components, dimensionless turbulent kinetic energy, and dissipation are shown in colour-expression figures, along with streamlines near the jet entrance to the main stream flow. The results agree with those from the existing references. We used a custom designed structured mesh for all models. Also, for democratization of the model applications a COMSOL® model-based App is built and introduced.
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Paper Nr: 8
Title:

Stochastic Models of Non-stationary Time Series of the Average Daily Heat Index
Authors:

Nina Kargapolova
Abstract: In this paper two numerical stochastic models of time series of the average daily heat index are considered. In the first model, time series of the heat index are constructed as a function of simulated joint nonstationary time series of air temperature and relative humidity. The second model is constructed under the assumption that time series of the heat index are non-stationary non-Gaussian random processes. Data from real observations at weather stations were used for estimating models’ parameters. On the basis of the simulated trajectories, some statistical properties of rare meteorological events, like long periods of time with high heat index, are studied.
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Paper Nr: 9
Title:

Investigation on Viscoelastic Fluid Behavior by Modifying Deviatoric Stress Tensor
Authors:

Nobuhiko Mukai, Erika Matsui and Youngha Chang
Abstract: One of the most challenging issues is to simulate and visualize liquid behavior, especially viscoelastic fluid, which has both characteristics of viscosity and elasticity. Although Newtonian fluid, which is represented by water, is generally analyzed with the governing equations, which are Navier-Stokes equation and equation of continuity. However, viscoelastic behavior is so complex that there is no established governing equation such as Newton’s equation of motion and Navier-Stokes equation. Some researchers employ Finite Element Method and others develop their own point based methods. In addition, there is a characteristic feature called “Spinnability” in viscoelastic fluid. That is, viscoelastic fluid is stretched so long and shows sudden shrink when the stretched fluid is broken. Then, we have been performing this spinnability simulation based on Cauchy’s equation of motion by modifying the stress term in constitutive equation. In this paper, we report the simulation results on viscoelastic fluid behavior for four kinds of deviatoric stress tensors constructing Cauchy’s equation of motion: only viscosity, only elasticity, linear combination of viscosity and elasticity, and complex modulus of elasticity.
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Paper Nr: 22
Title:

The Influence of the Level of the Flow Path Blockage at the Inlet on the Fan Characteristics
Authors:

Grigorii Popov, Oleg Baturin, Andrei Volkov, Daria Kolmakova, Vasilii Zubanov, Anastasia Korneeva and Yulia Novikova
Abstract: The paper presents the results of numerical simulation of the effect of flow nonuniformities at the engine inlet on the working process of the engine fan. Flow nonuniformities is created by pushing the interceptor into the flow part of inlet device like as it is often done during field tests. The authors have created a numerical model capable of considering non-stationary processes in the fan using nonlinear harmonic analysis. As a result, qualitative and quantitative estimates were obtained of the influence of overlapping of the inlet duct by the interceptor on the main parameters of the fan workflow. It is shown that the more the duct is blocked, the more its parameters are deteriorated. Moreover, the deterioration is not linear, but according to the dependence of the 2nd order.
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Paper Nr: 25
Title:

Design of a Circular-type Pod Silencer for a High-pressure Axial Flow Fan
Authors:

Hyun G. Kil, Chan Lee, Jong J. Park and Sang M. Yang
Abstract: A circular-type pod silencer has been designed to reduce a high noise level generated from an axial flow fan. The noise consists of two components such as discrete frequency noise component at blade passing frequency due to rotating impellers and broadband noise component due to turbulence produced in the axial fan. Main contribution into the high noise level is due to the discrete frequency noise component. In order to effectively reduce the noise level of the axial flow fan, the circular-type pod silencer has been modelled in this paper. In order to identify critical design parameters, finite element analysis (FEA) with commercial ANSYS acoustic code was implemented. The results of the design parametric study have been used to design the circular-type pod silencer that effectively reduces the high noise level of the axial flow fan in subway ventilation system.
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Paper Nr: 49
Title:

Analysis of the Dynamic Response Applied to a CubeSat
Authors:

Filiberto Candia, Enrique García, Joel Contreras, Gabriel Medel, Hector Vargas and Victor Galindo
Abstract: The automation of processes not only makes life easier, but also it optimizes the time spent in the explored fields to encourage humanity to look for new areas in order to develop their potential. This project presents the sequential development of a dynamic analysis applied to a structural model of CubeSat brand Pumpkin, simulated in NX Nastran, where the analysis of rigid body shapes, natural frequencies, sine sweep, random vibrations, and shock spectrum were performed. The results of the virtual tests are compared with the experimental tests to determine the reliability of space environment simulations. All of this with the aim of providing primary technical data of innovations based on: drag and lift, use of new materials such as 7075 aluminum alloy, 8A1-1Mo-1V titanium alloy, and maraging steel, and new design geometries such as cubes and spheres, with the purpose of systematizing and collecting them in a set of instructions to develop macros that can produce different models of the CubeSat standard unity. The simulation process followed an activities sequence carried out by the Knowledge Based Engineering System (KBES) in order to collect and manage the data focused on the Verification and Validation (V&V) of the Computer Aided Engineering (CAE) process in a correct way, to apply it in order to reduce the time and cover the standard GSFC-STD-7000A requirements appropriately.
Paper Nr: 53
Title:

An Hybrid Algorithm to Simulate Mice Following Residential Walls
Authors:

Moussa Sall, Jean-Marie Dembele and Jean L. Fur
Abstract: Commensal rodents such as mice that live in the proximity of human are well-known pests that can transmit diseases to man. An agent-based model is presented to formalize the spread of rodents in human habitations. We focus in this paper on the specific behaviour of mice consisting in walking along the walls (thigmotaxis). In order to simulate this behaviour we combine a cognitive architecture with an algorithm simulating rodents’ moves following residential walls. The cognitive model and the ‘wall following’ algorithm developed are successively described. Simulation configurations are tested to evaluate the robustness of the ‘wall following’ algorithm alone. In a data poor context this simple combined algorithm, using a discrete space, fulfils the basic needs to simulate a plausible mouse activity, towards a detailed representation of mice moves within a fluctuating environment.
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Paper Nr: 57
Title:

Optimization of Egress Controls of Fire Emergency Management Plans using Agent based Simulation: A Case Study of Ready-made Garment Industry
Authors:

Abdul Kaium, Sikder T. Hasan, Saqib Mehmood, Shakeel Ahmed, Anders S. Kristensen and Dewan Ahsan
Abstract: Ensuring a profound occupational health and safety in Readymade garment industries is a challenge for the developing countries despite having significant painstaking efforts. Recent statistics show that, the workers of this sector are in vulnerable conditions due to their exposure to fire risk at the factories and this risk gets worse during an emergency due to bottlenecks of egress components and clogging. Therefore, the emergency management plans of the RMG sectors needs to be optimized for safety of workers. The research work of this paper analyzes and explores the way of addressing underperforming emergency plans by optimizing evacuation strategies. For this purpose, an RMG factory in Bangladesh is selected as a case study. Based on the data provided by the factory management and survey regarding occupant’s perception, a simulation model in an evacuation simulation is built. Fire risks at the factory are analyzed through risk analysis tools for worst case scenario to assess the existing risks. The results reveal that the application of risk analysis tools along with an agent-based evacuation can benefit the entire RMG industry by reducing the risks of bottlenecks and clogging of egress controls that endangers lives of workers, thereby in optimizing the efficacy of fire emergency management plans.
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Area 4 - Application Domains

Full Papers
Paper Nr: 13
Title:

Simulation of Racing Greyhound Kinematics
Authors:

Md Imam Hossain, David Eager and Paul Walker
Abstract: This paper outlines greyhound dynamics results for yaw rate, speed, and the congestion pattern during a race derived through numerical modelling. The simulation results presented are also correlated to actual race data to validate modelling performance and reliability. The tasks carried out include the development of a numerical model for greyhound veering and race related supporting models, creating track 3D models replicated from actual survey data of the track, establishing a simulation environment that emulates an actual greyhound race, and the processing of both simulation and actual race data. The results show that greyhounds are susceptible to experience varying high acceleration in first five seconds into the race, during which a minimum average forward acceleration of 3.9 m/s2 was calculated, a peak yaw rate magnitude of 0.4 rad/s before the bend while transitioning into the track, and congestion during a race is affected by lure driving performance.
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Short Papers
Paper Nr: 1
Title:

Modeling Approaches for Controller Design using the Example of a Valve-driven Force-controlled Bearing Preload Element
Authors:

Georg Ivanov, Christian Rutter, Thomas Reuter and Thomas Burkhardt
Abstract: Conventional machine tool spindles are factory-equipped with a fixed bearing preload. Depending on the preload level, the field of application of a machine tool is limited to certain processing tasks. As part of a collaborative project between ICM e.V., Spindel-und Lagerungstechnik Fraureuth GmbH and SITEC Automation GmbH, funded by the European funding initiative EFRE, a novel adaptronic machine tool spindle has been developed. The new spindle offers the possibility of a variable adjustment of the bearing preload, whereby the machining spectrum of the machine tool can be significantly expanded. The functional principle is a rotationally symmetrical hydraulic bearing preload element integrated in the main spindle. By changing the pressure in the oil filled preload element, a relative displacement of the bearing rings is caused. The bearing preload can be varied proportionally to the relative bearing stroke. Aim of the investigation was to compare different levels of detail in modeling the main system components and the overall control system for the purpose of controller development. Therefor the Modelica-based simulation environment SimulationX® was used.
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Paper Nr: 11
Title:

Software-in-the-Loop-simulation of a District Heating System as Test Environment for a Sophisticated Operating Software
Authors:

Ophelia Frotscher, Thomas Oppelt, Thorsten Urbaneck, Sebastian Otto, Ingrid Heinrich, Andreas Schmidt, Thomas Göschel, Ulf Uhlig and Holger Frey
Abstract: With the expansion of renewable energies, district heating (DH) systems are becoming increasingly complex. Various heat sources like solar thermal plants and combined heat and power (CHP) plants are integrated in parallel, in addition thermal energy storages (TES) are often used to balance load and heat generation. Sophisticated software solutions are required to optimise the plant operation. Based on deterministic physical models and artificial neural networks, the software Heating Network Navigator (HN-Navi) is being developed to optimise the operation of such systems. Since tests in the real system are not possible for reasons of supply security, the HN-Navi is first tested in a software-in-the-loop (SiL) environment. TRNSYS (version 18) is used as simulation software to create a complex reference model (CRM) as basis for the SiL environment. The complexity of such real energy systems can lead to potentially high computing costs when it comes to simulating or optimising their operation as realistically and accurately as possible. For this reason, both software tools, i.e. HN-Navi and CRM, will be developed and tested with regard to the Brühl solar DH system in Chemnitz (Germany), whereby the finished software will also be used for other heat supply systems. TRNSYS offers the possibility to develop own models for all system components, with which a proper reproduction of the real system can be achieved. Within the scope of the project, practical tests and extensive quantitative software comparisons with the real system will also be carried out. The article reports on the development of this SiL environment and its practical feasibility.
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Paper Nr: 14
Title:

Study Simulated Epidemics with Deep Learning
Authors:

Yu-Ju Chen, Tsan-sheng Hsu, Zong-De Jian, Ting-Yu Lin, Mei-Lien Pan and Da-Wei Wang
Abstract: Simulation systems are human artifacts to capture the abstraction and simplification of the real world. Study the output of simulation systems can help us understand the real world better. Deep learning system needs large volume and high quality data, therefore, a perfect match with simulation systems. We use the data from an agent based simulation system for disease transmission, to train the deep neural network to perform several prediction tasks. The model reaches 80 percent accuracy to predict the infectious level of virus, the prediction of the peak date is off by at most 8 days 90 percent of the time, and the prediction of the peak value is off at most 20 percent 90 percent of the time at the end of the 7th week. We use some preprocessing tricks and relative error leveling to resolve the magnitude problem. Among all these encouraging results, we did encounter some difficulty when predicting the index date given information at the middle of an epidemic. We note that if some interesting concepts are difficult to predict in a simulated world, it sheds some lights on the difficulty for real world scenarios. To learn the effects of mitigation strategies is an interesting and sensible next step.
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Paper Nr: 16
Title:

Seamless Development of Robotic Applications using Middleware and Advanced Simulator
Authors:

Burtin Gabriel, Bonnin Patrick and Malartre Florent
Abstract: This paper addresses the issue of efficient transition from robotic simulation to field experiments and validation. The idea to ease this transition is to proceed step by step with small increments in complexity. A user begins with a simple and not so realistic simulation and evolve slowly to a complex and realistic one. We identified two axis to be tackled to achieve this steps by step complexity. The first axis is about the communication with the sensors: each sensors have a specific protocol. A simple simulation can by-pass this protocol by proposing a (universal) middleware connection while a complex one will emulate the real protocol to ensure a realistic data exchange between the processing unit and the sensor. The second axis is the opportunity to emulate a large spectrum of simulation complexity for a given sensor/environment. To increase the realism, similarly to the communication protocol, the realism of the sensor and its interactions with the environment can be increased from simple to the most realistic. These concepts are tested with a real use-case: the development of an indoor real-time localization system. The main development is done with a simulator compliant with our requirements. Afterward, the code designed with simulation is tested with a real robot for final validation.
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Paper Nr: 27
Title:

A Spiral Approach to Solve the Routing and Spectrum Assignment Problem in Ring Topologies for Elastic Optical Networks
Authors:

Nicolas Jara, Jesenia Salazar and Reinaldo Vallejos
Abstract: In this paper, we propose a simulation-based strategy to solve the routing and spectrum assignment problem in elastic optical networks with a static network operation for ring network topologies. First, the proposed method arrange the network users decreasingly according to their bandwidth demands. Next, we introduce the Spiral policy to allocate the frequency spectrum. This policy consists of assigning the resources to the user in a correlative manner, following a spiral, taking advantage of the ring topology. Remark that each user path is fixed, computed by any shortest path algorithm. We assess the performance and robustness of our model by comparing the proposal with two optimization models in small rings (5-8 nodes) and with the most referenced methods found in the literature for larger ring networks (5-50 nodes). The results show that consistently our method outperforms the ones proposed in the literature, in terms of network cost and fragmentation.
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Paper Nr: 44
Title:

Average Modeling of Fly-buck Converter
Authors:

Denys I. Zaikin, Simon L. Mikkelsen, Stig Jonasen and Konstantin Sirenko
Abstract: This document presents an average macro model for the fly-buck converter. The model can be used for both large and small signal modeling. Parasitic and lossy components are included in the model, and it is partially based on a conventional average switch model for a buck stage. For isolated output, the analytic solution of the average current in a secondary winding is proposed. The presented model is implemented in SPICE, and simulation results are compared to switching model simulation and experimental data.
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Paper Nr: 29
Title:

Simulating a Commercial Power Aggregator at Scale Design and Lessons Learned
Authors:

Gary Howorth and Ivana Kockar
Abstract: To evaluate aggregation models in the context of a power system, a software tool (the SmartNet simulator) has been developed to look at the impact of managing Distributed Energy Resources (DERs) on networks’ technical operation (e.g. power flows and voltage levels) and simulates wholesale and ancillary services market conditions. This paper focusses on the design and implementation of one of the aggregation models that addresses the Curtailable Generator / Curtailable Load (CGCL) aggregator. The paper outlines the design of such a software aggregator agent and discusses the lessons learned in simulating a more realistic large power grid system. The aggregator is represented as an agent based object orientated model using a financed based buckets system to aggregate bids from up to 300,000 devices across 10 -20,000 power nodes. The concept/implementation can be extended to include more sophisticated bidding strategies and to use multiple perspectives on tranches. Simulation and testing of such a large simulation system was challenging, and we have proved that it is possible to simulate the aggregation and clustering of different types of flexibility into a number of manageable bids in a timely manner.
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Paper Nr: 51
Title:

Simulation Effects on the Optical Response of Gold Nanoparticles
Authors:

Tanaporn Leelawattananon and Suphamit Chittayasothorn
Abstract: In this research work, we use simulation models for the investigation of the sizes and shapes of gold nanoparticles on BK-7 substrate base, which affect the optical characteristics in a large spectral range of the gold nanoparticles. Linearly polarized light with wavelengths of 300 – 800 nm are specified as the impact light on gold nanostructures. We try to find the suitable wavelength of the impact light when localized surface plasmon resonance takes place. The gold nanoparticles are spherical, elliptical oval, and 10nm x 40 nm block-shape and have their aspect ratio similar to the nanorod shape nanoparticles used in other experiments. The results are useful for the development of plasmonic complex nanostructure with tunable surface plasmon resonances which generate heat and have potential applications in medical thermal therapy.
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Paper Nr: 62
Title:

Explorations and Lessons Learned in Building an Autonomous Formula SAE Car from Simulations
Authors:

Dean Zadok, Tom Hirshberg, Amir Biran, Kira Radinsky and Ashish Kapoor
Abstract: This paper describes the exploration and learnings during the process of developing a self-driving algorithm in simulation, followed by deployment on a real car. We specifically concentrate on the Formula Student Driverless competition. In such competitions, a formula race car, designed and built by students, is challenged to drive through previously unseen tracks that are marked by traffic cones. We explore and highlight the challenges associated with training a deep neural network that uses a single camera as input for inferring car steering angles in real-time. The paper explores in-depth creation of simulation, usage of simulations to train and validate the software stack and then finally the engineering challenges associated with the deployment of the system in real-world.
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