International Journal of Simulation and Process Modelling (37 papers in press)
Simulating effect of parameters variation on the performance of an educational system
by Najat Messaoudi, Jaafar Khalid Naciri, Bahloul Bensassi
Abstract: The present study proposes a first model simulating the effect of variations of a group of parameters on the global performance of an educational system. To achieve the simulation, each training cycle of the educational system is broken down into different levels. The training unit is defined as the lowest component of this decomposition. A generic processor is selected for modelling each training unit. A mathematical modelling enabling simulation of the increase of learner's competence, based on a production function for each learner, is proposed. In order to perform a simulation it is necessary to specify the production function f, which relates the increase of the level of competencies of each learner to a set of parameters. Some parameter variations are studied, such as the time dependency (or on the training's duration), the class size, the personal capacity of each learner, which make it possible to obtain approximate expressions useful to carry out simulations. The obtained results show the variation of performance of a training unit versus number of learners, i.e the class size effect on the performance. The obtained curves clearly show the relationship between performance, variation in the number of learners and sensitivity of the pedagogical method, and establish that the performance ratio has different behaviors depending on the sensitivity of the pedagogical method to the number of learners. Thereafter, simulations of the effect of group homogeneity on the performance versus class size curves are presented.
Keywords: educational system; modelling; simulation; performance; assessment; class size; training program; competence; generic processor.
Numerical simulation of a cinema fire based on a fire dynamics simulator
by Zhian Huang, Yaru Meng, Rui Yang, Yukun Gao, Zhang Yinghua, Shuyi Wang
Abstract: In this paper, large-scale FDS (Fire Dynamics Simulator) model software was used to simulate a cinema fire. The reliability of the simulation results was verified by comparison with relevant research results, and some fire precaution measures were put forward. Based on the physical fire model of 1:1 a full-scale simulation of a cinema fire was carried out. By studying the flue gas, temperature and variation law of the CO concentration during the fire, it is found that the mechanical air-intake damages the stratification of smoke and air in the burning room to a certain extent. The lower air in the theatre is mixed with the upper high-temperature flue gas so that the temperature of the lower air is higher than that of the upper air. Meanwhile, the mechanical air-intake enhances the reducing speed of visibility. The results of this research provide a reference for the fire protection design of cinemas.
Keywords: cinema; fire dynamics simulator; evacuation time; numerical simulation.
Efficient modelling and simulation tool for nanoscale transistor sizing
by Abdoul Rjoub, Shihab AlKattab
Abstract: This paper proposes an efficient Delay Enhancement and Leakage Optimisation based on Transistor Sizing (DELOTS) algorithm for optimisation of digital CMOS at the transistor level for low power and high performance at 22 nm technology. The proposed algorithm integrates three models, Graph Model (GM), Mathematical Model (MM), and Heuristic Model (HM), working in a structured sequence to achieve the highest level of optimisation. Applying the proposed DELOTS algorithm shows significant improvement of PDP in the Full Adder circuit, 31%, and in the ISCAS C17 benchmark, 43%. DELOTS is proven to be one of the most efficient algorithms in digital CMOS optimisation at transistor level. In addition to simplicity and speed, DELOTS ensures finding the optimal solution and offers multi-purpose optimisation, where each parameter can be optimised as a stand-alone parameter or in combination with other parameters requiring optimisation.
Keywords: CMOS; algorithm; DELOTS; dissipation; leakage; propagation delay.
Optimisation of high efficiency tin halide perovskite solar cells using SCAPS-1D
by Usha Mandadapu, S. Victor Vedanaykam, K. Thyagarajan, B.J. Babu
Abstract: Hybrid perovskite solar cells are creating attention owing to the enormous growth of efficiency, exceeding 20%, indicating in the near future that these cells will become an alternative to the traditional silicon photovoltaics. For the commercialisation of low-cost, high efficiency perovskite solar cells, it is necessary to investigate the relation between the various material parameters, the device architectures and power conversion efficiency (PCE) of the devices. Three types of architecture are designed and simulated using the solar cell capacitance simulator (SCAPS-1D), used for the analysis of thin film photovoltaic architecture. One architecture is glass/ZnO:Al/TiO2/CH3NH3SnI3/Au, the second one is glass/TiO2/ZnO:Al/CH3NH3SnI3/CuI/Au, and glass/ZnO:Al/TiO2/CH3NH3SnI3/CH3NH3SnBr3/CuI/Au is the architecture of the third. Analysis was done by studying the effect of various material parameters on the device performance. It was observed that the second one (Model 2) shows the maximum PCE of 25.91%. This simulation work is useful to researchers in the design of low cost, non-toxic, high efficiency tin halide perovskite solar cells.
Keywords: optimisation; SCAPS-1D; material parameters; solar cell; efficiency; tin halide; perovskite.
CCUS evaluation and simulation in a Chinese oilfield
by Dongya Zhao
Abstract: This paper studies the evaluation issue of a preparatory CCUS in China. Economic and environmental evaluation are presented with the delicate simulations. The analysis of the evaluation results show that the CCUS project will be feasible if the oil price is enough high or the storage allowance can be given. The results will be useful for the future CCUS projects and for government decisions on CCUS.
Keywords: CCUS; economic evaluation; environmental evaluation; simulation.
A simulation technique for designing next-generation information and communication systems based on off-the-shelf microwave electronics computer tool
by Mikhail Belkin
Abstract: We review our known, updated, and newer models and simulation results using power microwave-electronics off-the-shelf computer tool NI AWRDE to pursue advanced performances corresponding to the last generation of key microwave photonics elements, such as semiconductor laser, photodiode, two types of electro-optic modulator, and multichannel reflecting Bragg grating. Based on them, the models of two key microwave photonics devices that fulfill particular basic processing procedures of a microwave-band network: microwave signal oscillation and microwave frequency conversion, and super-wide bandwidth photonic beam former for microwave photonics phased array antenna, are introduced and studied. As a result, we proposed and validated experimentally a new approach to model a broad class of promising analogue microwave radio-electronics systems based on microwave photonics technology.
Keywords: microwave photonics; nonlinear equivalent models; microwave-band optoelectronic circuitry elements and devices; optical beam-forming network; computer aided design.
An interactive, interoperable and ubiquitous mixed reality application for a smart learning experience
by Francesco Longo, Letizia Nicoletti, Antonio Padovano
Abstract: This article presents an innovative comprehensive platform that includes an interactive, interoperable and ubiquitous mixed reality application that will extend the ways cultural digital resources are created, disseminated, preserved and re-used. As part of an extensive research effort carried out by the authors to foster the use of the most recent technologies in the field of cultural heritage, this article goes further in the design and development of a prototype of an Intelligent, Interactive and Interoperable Comprehensive Platform for the 21st century Museums (I3-CPM). Since I3-CPM explores unconventional ways to deliver cultural contents (virtual and augmented reality, serious games, holography, simulation, knowledge-based systems, vocal interaction technologies, etc.), it is expected to provide users with a new and smart learning experience. The OUTSIDE-REAL application is here described as part of the I3-CPM framework: it provides intuitive navigation of mixed reality cultural contents and storytelling through an intelligent knowledge navigator and vocal assistant, called SOPHOS, thus offering the visitors a user-driven, interactive and meaningful learning experience at the cultural heritage site.
Keywords: cultural heritage; digital museum; mixed reality; augmented reality; intelligent agents; vocal assistant; smart learning; storytelling.
Simulation and design optimisation of broach tool geometry for enhancing material removal rate
by Vivek Kalyankar, Amey Pujari
Abstract: In this work, a broach tool geometry is considered and an attempt is made to simulate and optimise the geometry so as to enhance the material removal rate (MRR). Highly efficient DEFORM 3 D software is used for simulation and optimisation of the broaching tool, which is also reported in the literature and being used by various industries. The modified tool design is considered for machining of AISI 1045 and brass materials, and the optimised tool geometry has reduced the number of broach teeth from 44 to 14 in case of AISI 1045 work material and from 44 to seven in the case of brass material, thereby considerably reducing the tool cost. Moreover, the proposed optimum tool geometry has also given considerable improvement in the MRR for both the materials compared with previous results. Hence, the present approach may become useful to industries to improve the MRR and tool cost.
Keywords: design optimisation; broach tool geometry; tool design; DEFORM software; simulation.
Theoretical analysis and experimental study on heat transfer mechanism and thermal insulation properties of composite insulation coating
by Li Wei, Xianfei Geng, Andong Du
Abstract: In this research work, a numerical simulation and experimental study were carried out on the preparation of thermal insulation coating with modified acrylic resin and high temperature adhesive formulations as the base material, ceramic fibre as a reinforcing material, and spherical hollow particles as heat-insulating aggregate. The theoretical study based on simulation was investigated to analyse thermal conductivity of the coating, and the experimental study was carried out to analyse the main factors affecting the performance of the insulation coating, as well as its microstructure. The simulation results show that the thermal conductivity of the coating is the sum of those of the film-forming binder and filler; it is proportional to the thermal conductivity of the coating in the solid phase. The experimental results show the temperature of the coating outer surface can be reduced to 43℃ when the volume fraction of spherical hollow particles ratio is 15 mesh:20 mesh:24 mesh = 1:2:8, the amount of fibre is 12%, pigment to binder ratio is 4:6, the coating thickness is 40 mm, and the temperature of inner surface is at 350℃. It is shown through analysing the microstructure of the coating that the heat conduction can be effectively prevented if the coating structure consists of closely packed hollow spheres with different sizes of particles as vacuum chambers to form numerous 'vacuum walls', and a three-dimensional networked structure of the coating is formed in the presence of the fibres.
Keywords: numerical simulation; experimental study; insulating coating; coating structure; heat transfer mechanism; insulation performance.
A new hyperchaotic temperature fluctuations model, its circuit simulation, FPGA implementation and an application to image encryption
by Sundarapandian Vaidyanathan, Ahmad Taher Azar, Karthikeyan Rajagopal, Aceng Sambas, Sezgin Kacar, Unal Cavusoglu
Abstract: In this paper, we propose a new hyperchaotic temperature fluctuations model and describe its modelling in detail. We study the characteristics of the new model, such as its phase portraits, rest points, symmetry, invariance, Lyapunov characteristic exponents, bifurcation analysis, etc. In fact, it is shown that the new model has a self-excited, two-scroll, hyperchaotic attractor with complex properties. The circuit simulation of the new model is carried out in MultiSim to verify the feasibility of the theoretical model. In addition, FPGA implementation of the new model is also presented. An engineering application of the new model for image encryption is also described.
Keywords: hyperchaos; hyperchaotic systems; circuit design; FPGA implementation; Lyapunov exponents; image encryption.
Simulation, and application of water content determination process of single well crude oil
by Zhaohong Xiong
Abstract: The water content data of wellhead crude oil is an important basis for determining the production accounting of oil fields, the adjustment of block unit and the effectiveness of the single well operation, which is related to enterprise cost effectiveness. For a long time, the distillation method has been used in water cut analysis of wellhead crude oil in Shengli Oilfield of China, resulting in serious oil and gas volatilisation, great safety hazard and excessive consumption of solvent oil. To solve these problems, this paper explores the assay method for the moisture content of crude oil, and carries out a feasibility analysis of the distillation method, capacitance method, electrically extrication method and centrifuge method. Based on the simulations, the distillation method and centrifuge method were optimised and compared by field experiments, and the method for testing water content of crude oil in a single well was improved. The improved method has been applied in the oil production plant, which has achieved a good effect of reducing cost and increasing efficiency compared with the original method.
Keywords: water cut measurement; distillation method; centrifuge method; TQCM.
Agent-based modelling and simulation of task execution and coordination in distributed organisations: the pyscho-social dynamic interaction perspective
by Haibin Liu, Yufang Cheng, Qinghe Bo
Abstract: This paper presents a psycho-social dynamic model of members commitment to perform local tasks and global tasks under a distributed context. Based on the theory of planned behaviour, we explore how local task self-efficacy and IT self-efficacy evolve with a computational model. The simulation results of the aerospace industry show that the organisation will evolve to a non-balanced state of development. Moreover, sites that form the distributed organisation will evolve to independent locations in the end. For overcoming these situations, the study proposes a strategy called 'resisting foreign aggression Home Safe'. Moreover, a high rate of global task accomplishment can obtained by improving members IT self-efficacy, which brings in more communication and coordination between separated sites. For distributed organisations, the higher and the lower coordination are not rewarding, while the high local task self-efficacy and the moderate IT self-efficacy are beneficial.
Keywords: distributed organisations; self-efficacy; theory of planned behavior; agent-based model; simulation.
Stability-based model for evacuation system using agent-based social simulation and Monte Carlo method
by Makhlouf Naili, Mustapha Bourahla, Mohamed Naili
Abstract: The agent-based modelling is used for modelling many complex dynamic systems, especially those including autonomous individuals, such as human beings' societies, animal societies, robots, insect societies, etc. Evacuation systems such as those needed for supermarket buildings are considered as complex dynamic systems. In these systems, we have to deal with the problem of rescuing a high number of people of different ages, sex, physical characteristics, etc. Furthermore, this process mostly runs in buildings with different constraints such as locations of the rows of shelves, exit gates, etc. On one hand, in order to deal with disasters such as fire propagation, studying this kind of system using a dynamic model has a great importance in order to avoid the maximum of casualties. On the other hand, the model that represents this kind of system must take into account several factors, such as time, the buildings characteristics and peoples characteristics. In this study, an agent-based model has been designed to visualise the dynamic system behaviour via these internal entities that often interact. Additionally, we use some dynamic data mining methods such as Monte Carlo method to calculate the stable characteristics of this model via a probabilistic approach.
Keywords: agent-based modelling; dynamic data mining; dynamic models; evacuation building system; Monte Carlo simulation; stability; steady state.
K-DBSCAN: an efficient density-based clustering algorithm to support parallel computing
by Chao Deng, Jinwei Song, Saihua Cai, Ruizhi Sun, Yinxue Shi, Shangbo Hao
Abstract: DBSCAN is the most representative density-based clustering algorithm and has been widely used in many fields. However, the running time of DBSCAN is unacceptable in many actual applications. To improve its performance, this paper presents a new two-dimensional density-based clustering algorithm, K-DBSCAN, which successfully reduces the computational complexity of the clustering process by a simplified k-means partitioning process and a reachable partition index, and enables parallel computing by a divide-and-conquer method. The experiments show that K-DBSCAN achieves remarkable accuracy, efficiency and applicability compared with conventional DBSCAN algorithms, especially in large-scale spatial density-based clustering. The time complexity of K-DBSCAN is O(N^2/KC), where K is the number of data partitions, and C is the number of physical computing cores.
Keywords: DBSCAN; data mining; parallel computing; K-means; density-based; clustering; spatial data.
Cognitive smart environment: an approach based on concept hierarchies and sensor data fusion
by Franco Cicirelli, Antonio Guerrieri, Alessandro Mercuri, Giandomenico Spezzano, Andrea Vinci
Abstract: Sensor data fusion gathers technological solutions which are devoted to collecting, classifying and combining data from multiple (and possibly diverse) sensors deployed in a smart environment in order to augment knowledge about the system so realising cognitive behaviour. The goal is that of making more effective the analysis and management of acquired data as well as that of promoting the realisation of cognitive systems that can sense the environment, reason about what is happening around them and properly act for reaching some purposes. Anyway, the development of such cognitive smart environments asks for suitable approaches able to jointly face issues such as heterogeneity, sensor/actuator management, system reactivity, behavioral modelling, and context awareness. This paper proposes a multi-tier approach, based on concept hierarchies and sensor data fusion, dealing with the above aspects in a modular way. The approach favours separation of concerns and abstractions. It relies on the use of the agent metaphor and statecharts. The use of the iSapiens IoT-based platform is then suggested for development purposes. As a significant case study, the approach was exploited for the development of a smart museum by making cognitive some artworks (statues) of the MAB open-air museum located in the city of Cosenza, Italy.
Keywords: sensor data fusion; cognitive internet of things; multi-agent systems; statecharts; smart environment; context awareness; smart museum.
Swarm intelligent algorithm For re-entrant hybrid flow shop Scheduling Problems
by Zhonghua Han, Xutian Tian, Xiaoting Dong, Fanyi Xie
Abstract: In order to solve the Re-entrant Hybrid Flowshop (RHFS) scheduling problems and establish mathematics scheduling models, this paper uses Wolf Pack Algorithm (WPA) as the global optimisation. For local assignment, it takes maximum residential time-oriented rule. Scouting behaviours of wolves are changed in the former optimisation by means of levy flight, extending searching ranges and increasing the rapidity of convergence. When it comes to local extremum of wolves, the individual with high similarity of dynamic changes adds diversity. Hanming distance is used to judge individual similarity for increased quality of new one, strong algorithm ability and energetic revolution. A painting workshop in a bus manufacture enterprise have some typical features of re-entrant hybrid flowshop. Regarding it as the algorithm applied target, this paper focus on resolving this problem with WPA and various advanced algorithms. The results show that advanced algorithms can solve re-entrant hybrid flowshop scheduling problems effectively.
Keywords: re-entrant hybrid flow shop; mathematics scheduling models; Hanming distance; levy flight; swarm intelligent algorithm.
The structure optimisation of hydraulic mechanical screw pump
by Zhenfu Ma
Abstract: In the current stage of oilfield development, the screw pump is an advanced mechanical oil recovery process. In the process of lifting oil and other liquids in the well, the screw pump has good and stable characteristics of pumping force under high pressure This paper takes Shengli Oilfield water flooding development as the engineering background, aiming at the problem that the flow ratio of the screw motor and the screw pump affects the efficiency. The changing rules of influencing factors, such as luffing coefficient and eccentric coefficient, over the flow area, and the relative sliding velocity are modelled and analysed. With the amplitude coefficient and eccentric coefficient as decision variables, the equatorial short hypochromic curve is optimised to get the best ratio of each head of the parameters and end line type.
Keywords: screw pump; screw motor; luffing coefficient; eccentricity coefficient; optimisation.
Special Issue on: Computational Thinking and the Development of Complex Systems
Morphology-based visible-infrared image fusion framework for smart city
by Guanqiu Qi, Zhiqin Zhu, Yinong Chen, Jinchuan Wang, Qiong Zhang, Fancheng Zeng
Abstract: Following the development of smart city, informative images play a more and more important role in recognition, detection, and perception. As an efficient way, the image fusion technique integrates information from multiple images. Sparse-representation based approaches are often applied to image fusion. Although an informative and compact dictionary is a key component of the sparsity-based image fusion method, it is difficult to obtain such a complete and non-redundant dictionary. This paper proposes a hierarchical image fusion framework that applies layer-by-layer deep learning techniques to explore the detailed information of images and extract key information of images for dictionary learning. According to morphological similarities, this paper clusters source image patches into smooth, stochastic, and dominant orientation patch groups. Thus more detailed information can be extracted from source images for dictionary construction. Three clustered image-patch groups are decomposed into high-frequency and low-frequency components by using Gaussian blur. High-frequency and low-frequency components are fused by Max-L1 and L2-norm based weighted average fusion rules, respectively. The fused low-frequency and high-frequency components are combined to obtain the final fusion results. The comparison experimentations are simulated to evaluate the fused image in image feature, information, structure similarity, and visual perception. The results confirm the feasibility and effectiveness of proposed image fusion solution.
Keywords: image fusion; sparse representation; dictionary learning; geometric information classification; smart city.
DEVSServer: ambient intelligence and DEVS modelling-based simulation server for epidemic modelling
by Mostefa Mokaddem, Baghdad Atmani, Abdelmalek Boularas, Chihab Eddine Mohammed Omar Mokaddem
Abstract: To improve Disease Surveillance Systems (DSS) with faster and more accurate outbreak detection and epidemic propagation capabilities, the availability of fine-tuned models is required, along with the design of server-based solutions that simulate the effects of public health authorities measures, and integrate Ambient Intelligence (AmI) capabilities to semantise epidemic models. Hosting Discrete Event System Specifications (DEVS) models, these AmI servers and their communication protocols are different, miscellaneous and require interoperability. The Triple Space Computing (TSC) paradigm addresses interoperability by sharing information represented in a semantic format through a common virtual space. In this paper, we present DEVSServer, a fully distributed TSC simulation server solution (middleware) designed to meet the needs of parallel and distributed discrete event simulation. DEVSServer defines a Service Oriented Architecture (SOA) interface for the TSC operations. This interface complies with DEVS formalism and focuses on simplicity, conviviality and modularity, so that a single or many simulations that support different models can still interact. To assess DEVSServer, we provide a tuberculosis epidemic model simulation in time-varying temporal network with a genetic programming immunisation strategy approach.
Keywords: ambient intelligence; triple space-based computing; service oriented simulation; parallel discrete-event simulation; DEVS; disease surveillance system; epidemic modelling; temporal network; genetic programming; immunisation strategy.
Finite-time synchronisation of a memristive hyperchaotic circuit based on a Lorenz system with transmission delay
by Hongjuan Wu, Xiang Hu, Yuming Feng
Abstract: In this paper, we analyse the characteristics of one type of circuit structure that is extended from a simplified Lorenz system by taking a memristor as feedback. Considering the transmission time delay between the master system and slave system, we used a compound finite-time synchronisation signal controller, which consists of a general feedback control signal and a fine adjustment signal, to ensure the synchronisation of two memristive hyperchaotic circuits based on the Lorenz system. Based on Lyapunov stability theory, finite-time control, matrix inequality, and considering the transmission time delay, the finite-time synchronisation condition for this type of memristive hyperchaotic circuit based on the Lorenz system with transmission time delay via finite-time controller is given. Finally, simulation results are used to verify the feasibility and effectiveness of this method.
Keywords: memristor; Lorenz system; transmission time delays; finite time.
Three-dimensional pedestrian dead reckoning method based on gait recognition
by Min Huang, Hua-Zhao Li, Xia Wu
Abstract: With the widespread use of sensors on smartphones, it is becoming easier to use pedestrian dead reckoning (PDR) with smartphones, and making it possible to rely on smartphones for accurate indoor positioning. The existing PDR model is based on two-dimensional effective modelling method of the indoor space, said lack of three-dimensional space. In this paper, the concept of step height is introduced in a creative way, and a three-dimensional PDR model based on gait recognition is proposed, which makes it possible to locate indoor three-dimensional space. The three-dimensional PDR model uses an improved method of step detection and the average accuracy of the model is higher than the traditional 2D PDR model. Meanwhile, the experiment also proved the effectiveness and practicality of the three-dimensional model of the PDR.
Keywords: three-dimensional pedestrian dead reckoning; 3D-PDR; step detection; gait recognition; step height estimation.
Travel pattern modelling and future travel behaviour prediction based on GMM and GPR
by Wen Shen, Zhihua Wei, Chao Yang, Renxian Zhang
Abstract: How to use historical data of public smart cards to predict user behaviour attracts a lot of attention. A number of applications depend on the ability to foresee the behaviour of users, for instance, traffic flow prediction. This paper aims at modelling travel patterns and predicting future travel behaviour of Metro System smart card holders. We apply a Gaussian mixture model (GMM) on time series to model user behaviour. We propose a new method based on the perplexity for finite GMM and use an expectation-maximisation (EM) algorithm to estimate the parameters of GMM. In order to predict the future travel behaviour (such as the probability of travelling at a certain moment), we introduce the Gaussian process regression (GPR) to define distributions over GMM, which can not only tell the probability of travelling at a certain moment but also tell the reliability of the prediction. Experimental results show that our whole system in the centre of GMM and GPR can effectively mine the hidden knowledge of historical data of smart cards, and thus model the travel patterns and predict future travel behaviour.
Keywords: Gaussian mixture model; perplexity; Gaussian process regression; travel pattern modelling; behaviour prediction.
Special Issue on: I3M2016 New Advances of Modelling and Simulation for BusinessProcesses, Production, Services and Supply Chain
The role of horizontal cooperation to improve service quality in last-mile distribution
by Adrian Serrano-Hernandez, Patrick Hirsch, Javier Faulin, Christian Fikar
Abstract: Horizontal cooperation has revealed itself as a new catalyser for goods distribution optimisation in order to achieve greater efficiency. Moreover, urban distribution is facing a new paradigm as e-commerce is growing rapidly and traffic restrictions in inner cities are becoming more frequent. While the economic benefit derived from the application of horizontal cooperation has been widely analysed by practitioners and in academia, this paper assesses the impact of horizontal cooperation on service quality in a business-to-business relationship. An agent-based simulation model is presented to measure savings in lead times due to various horizontal cooperation agreements under consideration of trust-related factors. Additionally, the effect of the store-wholesaler topology is investigated, providing meaningful insights on the potentials of horizontal cooperation. Results of computational experiments show that cooperation enables companies to reduce lead times substantially, which increases service quality and competitiveness.
Keywords: horizontal cooperation; lead time; coalition; service quality; simulation; last-mile distribution; trust; sharing.
Simulation of counter drugs operations based on geospatial technology for use in a military training simulator
by Ornprapa Robert, Chamnan Kumsap, Ampun Janpengpen
Abstract: This article reports the adoption of Potential Surface Analysis (PSA) to model drug trafficking routes in Thailand for military training scenarios of a small-arms simulator. GIS data layers were used for the analytic hierarchy process. Experts were gathered to brainstorm for potential factors and their ratings based on knowledge, expertise and judgements. Physical, drug-aspect and socio-demographic factors were the main factors, and were further separated into sub-factors. The Consistency Ratio (CR) was calculated at 0.09, the significance of the factors became less than 0.10, making the consistency acceptable. The PSA revealed potential drug-trafficking routes that were cross-checked with genuine routes. The created military training scenarios were validated by experienced military and security officials. The average satisfaction of 3.92 with the standard deviation of 0.75 confirms that the integrated methodology of modelling drug trafficking routes using PSA is another optional approach to upgrade the military small-arms training simulator.
Keywords: modelling and simulation; drug trafficking; geospatial technology; analytic hierarchy process; military simulation and training.
A case of a modelled saturation level for cooperative flight departures
by Nina Schefers, Juan José Ramos González, Jenaro Nosedal-Sánchez
Abstract: Owing to increasing air traffic operations, the development of advanced Decision Support Tools (DSTs) in Air Traffic Management (ATM) is driven forward to guarantee sustainable transport logistics to balance airspace capacity with user demands. In this paper, the tuning of Calculated Take-Off Times (CTOTs) as a tool for mitigating the propagation of perturbations between trajectories in dense sectors is analysed. The proposed methodology uses a powerful tool for predicting potential spatio-temporal concurrence events between trajectories over the European airspace. In the first place, the aim is to remove the detected concurrence events by considering bounded time stamp adjustments on strategic agreed points of the aircraft trajectory. In the second place, the model is extended to identify route interdependencies of over-constraint topologies that could lead to a saturation event. The approach is based on a robust constraint programming model aiming to determine the feasible time stamp changes considering reference-based trajectories.
Keywords: air transportation; constraint programming; air traffic management; decision support tools; airspace capacity; trajectory-based operations; air traffic control; air traffic flow management; conflict detection; scheduling; reference-based trajectory; calculated take-off time; reification.
Special Issue on: I3M2016 Recent Developments of Simulation Theories, Methodologies, Techniques and Tools
Analysis of fraud controls using the PaySim financial simulator
by Edgar Alonso Lopez-Rojas, Stefan Axelsson, Dejan Baca
Abstract: Fraud controls for financial transactions are needed and required by law enforcement agencies to flag suspicious criminal activity. These controls, however, require deeper analysis of the effectiveness and the negative impact for the legal customers.
Owing to the intrinsically private nature of financial transactions, this analysis is often performed after several months of actively using fraud controls. In this paper, we present an analysis of different fraud prevention controls on a mobile money service based on thresholds using a simulator called PaySim. PaySim uses aggregated data from a sample dataset to generate a synthetic dataset that resembles the normal operation of transactions and injects malicious behaviour. With technology frameworks such as agent-based simulation techniques, and the application of mathematical statistics, we show in this paper that the simulated data can be as prudent as the original dataset for setting optimal controls for fraud detection.
Keywords: Multi-agent-based simulation; MABS; financial fraud; mobile money; fraud detection; synthetic data.
Novel robustness measures for engineering design optimisation
by Philipp Fleck, Michael Kommenda, Thorsten Prante, Michael Affenzeller
Abstract: This paper presents novel robustness measures to analyse and compare the robustness of solutions for constrained optimisation problems in the field of engineering design optimisation. First, we define uncertainty in production processes and present a method to quantify uncertainty. Based on the variations of a solution that are introduced by uncertainty, we want to assess the robustness of those solutions towards those variations. We show how a solution's quality and feasibility (with regards to constraint violation) change with increasing uncertainty and discuss how those changes determine the robustness of that solution. Furthermore, we present a method of aggregating that information into a single, real-valued robustness measure.
This novel robustness measure can be used to select solutions that have a high robustness along with a high quality. To test the presented measures extensively, we apply them to various solutions for benchmark problems from published literature in the field of engineering design optimisation.
Keywords: engineering design optimisation; uncertainty; robustness; optimisation; benchmark; constrained optimisation; multi-objective.
Setting up a serious game for a major incident in industrial plant management: investigation of the learning effect
by Ivan Ferretti, Simone Zanoni, Lucio Enrico Zavanella
Abstract: In recent years, the introduction of virtual simulation has allowed improvement of the management of major incidents by developing tools (or serious games) able to increase awareness of coordination and decision-making abilities in emergency situations. This study presents the results of a new serious game that simulates activities, procedures and processes planned to be implemented to manage the aid during a major incident that may occur in industrial plants. In particular, the serious game presented is based on a discrete event simulator, and it is able to reproduce emergency situations in which the players can improve their own management abilities through repetitive random sessions. A detailed analysis of the learning effect over different scenario settings has been investigated through the initial application of the tool to differently experienced set of users. The results presented show how the use of the simulator may significantly improve the awareness of coordination and decision-making abilities in emergency situations.
Keywords: simulation; serious games; major incident; training; decision-making.
System dynamics for the water footprint assessment and simulation in the bioethanol production
by Armin Trujillo-Mata, Guillermo Cortes-Robles, Cuauhtemoc Sanchez-Ramirez, Julio Blanco-Fernandez, Emilio Jimenez-Macias
Abstract: The bioethanol industry is one of the growing sectors worldwide which is seeking for sustainability along its supply chain. The increasing demand for bioethanol means this industry faces a conflict: to increase productivity without compromising the future natural resources such as water. This work proposes to integrate the water footprint assessment methodology to the supply chain analysis using system dynamics. In this paper, the application of the synergy is to assess and simulate the water footprint of the bioethanol production stage using the system dynamics methodology. System dynamics could be a useful approach to model and simulate the water footprint of bioethanol supply chain and estimate its impact on water resources for the next years.
Keywords: bioethanol supply chain; system dynamics modelling; water footprint assessment; causal loops diagram.
Enterprise operating system framework: federated interoperability based on HLA
by Joseph Rahme Youssef, Gregory Zacharewicz, David Chen, Zhiying Tu
Abstract: Operating System (OS) is a well-known concept in computer science as an interface between human and computer hardware (MacOS, Windows, IOS, Android,). In the perspective of developing the future generation of enterprise systems based on IoT and cyber-physical system principles, this paper proposes to develop an Enterprise Operating System (EOS) that will act as an interface between enterprise business managers and enterprise resources performing enterprise operations. The paper presents at first a set of requirements and functionalities of EOS. Then a survey on existing relevant works is given and mapped to the requirements. After that the existing models related to the federated enterprise interoperability are presented. The architectures of envisioned EOS and the federated interoperability are outlined. The last part draws some conclusions and gives future perspectives.
Keywords: operating system; architecture; model; infrastructure; interoperability.
Simulation model generation for warehouse management: case study to test different storage strategies
by Antonio Vieira, Guilherme Pereira, Luis Dias, Jose Oliveira
Abstract: A simulation model generator was developed to help a company of the Bosch Group to reduce costs in time and space within its warehouse. The simulation models are automatically created in Simio and can simulate pickers riding milk runs to collect containers from the warehouse, to satisfy the needs of production lines, enabling warehouse management by testing different storage strategies. Thus, the purpose of this paper is to present the developed generator and to use it in a case study, to test different storage policies for the company. The generator was validated, and the simulation model was automatically created. With this tool, some suggestions could be made to the company in question. Namely, it was shown that it would not be possible to maintain the FIFO rule and, at the same time, eliminate the upper floor of all racks for ergonomic reasons. To allow this, the rate of replacing containers should be synchronised with the needs of production lines. Alternatively, it was also shown that the performance of the warehouse would improve by dividing it into zones allocated to each milk run.
Keywords: simulation; warehouse management; milk run; picking; object modelling; Simio; simulation model generator.
Special Issue on: Modelling and Simulation of Chaotic Processes
A new biological snap oscillator: its modelling, analysis, simulations and circuit design
by Sundarapandian Vaidyanathan, Moez Feki, Aceng Sambas, Chang-Hua Lien
Abstract: In this work, we build a new four-dimensional autonomous biological snap oscillator model for enzyme-substrate reactions in a brain waves model. We investigate the process modelling of the new oscillator via phase portraits, simulations, dissipativity, symmetry, Lyapunov exponents, Kaplan-Yorke dimension, bifurcation analysis, Poincare map, etc. In addition, it is interesting that the electronic circuit model of the new biological snap oscillator is also investigated and phase portraits are analysed in MultiSIM.
Keywords: chaos; chaotic systems; circuit design; dissipativity; Lyapunov exponents.
Complex walking behaviours, chaos and bifurcations, of a simple passive compass-gait biped model suffering from leg length asymmetry
by Hassène Gritli, Nahla Khraief, Safya Belghith
Abstract: This paper is concerned with the analysis of the displayed nonlinear phenomena, chaos and bifurcations, in the planar passive dynamic walking of the planar compass-gait biped model under a leg length asymmetry as it goes down an inclined surface. The passive dynamic walking of the compass-gait model is modelled with an impulsive hybrid nonlinear dynamics. In this work, we present a normalised dynamics expressed in terms of dimensionless ratios. Our analysis and simulation of the passive bipedal gaits is realised mainly through bifurcation diagrams, where a normalised leg length discrepancy is adopted as the bifurcation parameter. We report the exhibition of complex behaviours, namely the period-doubling bifurcation, the cyclic-fold bifurcation, the period-doubling route to chaos, the period-remerging scheme, the boundary crisis, etc. We demonstrate also the exhibition of the Neimark-Sacker-2 bifurcation by investigating the tendency of the characteristic multipliers of the Jacobian matrix of the Poincar
Keywords: compass-gait model; leg length asymmetry; chaos; bifurcations; hysteresis phenomenon; Neimark-Sacker-2 bifurcation.
String of scrolls from a time-delayed chaotic circuit
by Fadhil Rahma Tahir, Ghaida A. Al-Suhail, Mariam Hussien Abd
Abstract: Over the last few decades, complex multi-scroll chaotic attractors generated through electronic circuits have considerably been raised. Therefore, this paper concerns the design and implementation of multi-scroll chaotic attractors such as 2-scrolls, 3-scrolls and 4-scrolls generated from a first-order delay differential equations. Modelling a time-delayed feedback chaotic system considers a simple nonlinearity piecewise-linear (PWL) function to generate the chaotic attractors with an odd/even numbers of scrolls. The delayed feedback consists of a cascade of Bessel filter and the design of a circuit that generates a string of scrolls chaotic attractors that depends on the number of intersection points of nonlinearity of the PWL function with a state variable. The simulation results reveal that the multiple-scroll chaotic attractors can be successfully reproduced using PSpice. The implementation based on circuit-switching mode with simple components, such as resistors, capacitors, and operational amplifiers, is also presented.
Keywords: time-delayed chaotic circuits; string of scrolls; feedback circuits; Pspice.
Extreme multistability in hyperjerk memristive system with hidden attractors and its adaptive synchronisation scheme
by Dimitrios Prousalis, Christos K. Volos, Ioannis Stouboulos, Ioannis Kyprianidis
Abstract: This research work presents the study of the phenomenon of extreme multistability in a novel 4D hyperjerk memristive system. The proposed system appertains to the category of dynamical systems with hidden attractors due to infinite equilibrium points. The behaviour of the system is investigated through numerical simulations, by using well-known tools of nonlinear theory, such as phase portrait, bifurcation diagram and Lyapunov exponents. Also, this work showed that the extreme multistability phenomenon of coexisting infinitely many attractors behaviour depends on the initial conditions of the variables of the system. Moreover, the case of chaos synchronisation of the system with unknown parameters, using adaptive synchronisation method, is investigated.
Keywords: memristor; memristive systems; hyperjerk systems; extreme multistability; hidden attractors; adaptive control.
Secure communication and image encryption scheme based on synchronisation of fractional-order chaotic systems using backstepping
by Manoj Shukla, B.B. Sharma
Abstract: A synchronisation strategy of fractional order nonlinear dynamical systems is used to address the problem of secure communication by introducing additional security features. Initially, a backstepping-based controller is designed for synchronisation of two similar fractional-order chaotic systems in a master-slave configuration. The controller obtained is divided into two parts, with one part transmitted through the communication channel and the other part designed at the receiver end so as to obtain synchronisation between master and slave system. Further, only two signals are transmitted, of which one has the message signal embedded and the other is a complex combination of master states, which will be used for synchronisation purpose at the receiver end for recovery of the message signal. The initial conditions, system parameters, fractional orders, the structure of controller and the combination of master system states form a large key set that should be known in advance in order to breach the security. Here, the scheme for secure transmission of speech signal is presented first and further a scheme for image encryption is given. The simulation results and security analysis using different quantitative measures are presented at the end to demonstrate the applicability and effectiveness of the proposed scheme.
Keywords: chaotic synchronisation; backstepping; fractional-order chaotic systems; secure communication; image encryption.
Stability study and dynamical analysis of the multicellular chopper
by Philippe Djondine, Jean-Pierre Barbot, Malek Ghanes
Abstract: The dynamical properties of a two-cells chopper connected to a particular nonlinear load is described in this paper. Some interesting and complex attractors are obtained. We analyse the system by means of Lyapunov exponents, fractal dimension, Poincar
Keywords: chaotic behaviour; multicellular converter; nonlinear dynamics; dynamical properties; dissipative dynamics; equilibria and stability.