International Journal of Simulation and Process Modelling (19 papers in press)
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.
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.
Cogent: a coherence-driven cognitive agent modelling and experimentation framework
by Sunit Sivaraj, Levent Yilmaz
Abstract: Most agent modelling and simulation languages lack high-level syntactic features necessary for cognitive modelling. In this paper, we present Cogent, an interactive coherence-driven agent specification and simulation platform and demonstrate its use in ethical decision-making. The underlying strategy is based on the concept of a connectionist, interactive activation model that implements the theory of coherence. Agents in the Cogent language are specified by a Domain Specific Language (DSL). The DSL provides the syntax for specifying the decision- making strategy along with its cognitive coherence model. The framework also provides the ability to model complex hierarchical cognitive network structures. To illustrate the utility of Cogent, we explore a machine ethics case study.
Keywords: cognitive agent; coherence; ethical decision making; cognitive computing; domain-specific language.
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: 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.