In this paper, the effect of load bundling on overall costs, service level, and CO$_2$ emissions is evaluated for a multi-stage, multi-item supply chain. A simulation-based optimisation approach is used to optimize the inventory management parameters reorder point and lot size. The optimisation approach consists of a simulation model and a metaheuristic search procedure, which is a subclass of the

Simulation of ad hoc networks requires the use of a realistic human mobility model to give credibility to computer-based performance evaluations. To this end, a number of models have appeared in the literature from which the self-similar least-action walk model (SLAW) stands out as an approach mainly intended to incorporate several statistical properties of human motion. Although it is generally accepted

ABSTRACT This paper describes the modelling process of soft-linking two system dynamics models of the automotive ecosystem: the Powertrain Technology Transition Market Agent model and the Transport, Energy, Economics, Environment model. The objective of this work is to explore future battery electric and plug-in hybrid electric powertrain deployment in key electro-mobility markets: China, European

One strategy to reduce inventories and increase on-time delivery is to use Advanced Demand Information (ADI) in which customers place their orders ahead of their due date. ADI can be divided into perfect or imperfect information. Under perfect ADI, customers send accurate demand information to the suppliers, specifying exact quantities and due dates. Under imperfect ADI, customer orders’ quantities

This work focuses on internal logistics (IL), which is defined as the flows of materials inside the same business or the same plant. We centre on the IL activities of a car-assembling company. The main objective is to propose simulation models’ concepts that evaluate assembling lines under the IL point of view. We present a real case study based on SEAT S.A., a company in the Volkswagen group. We developed

A scheduling algorithm is crucial for running a simulation model so that tasks can be performed efficiently.The traditionally used blade-based parallel engine system cannot be adapted to a new simulation model. This study proposed a combined dynamic priority and static method, that is, a hybrid load-balancing scheduling (HLB) algorithm. The algorithm is given priority according to the operating cycle

The Basel III regulation raised the minimum capital requirements for banks. However, its implementation may not have reduced systemic risks. Academicians investigating optimal banking regulations do not have a consensus on whether to increase or decrease capital requirements. Here, we use the agent-based approach to study capital regulation and its implications on the evolution of the banking system

The reliability of the transportation network is studied by simulating the attack on the important edges. The important edges are deliberately attacked, and the impedance of the attacking edges is set to infinity. Then the influence of the characteristics of single failure edge on network reliability change and the influence of failure edge number on network reliability change are studied. Two test

This paper introduces a new approach to hybrid traffic modelling, along with its implementation in software. The software allows modellers to assign traffic models to individual links in a network. Each model is a plugin that implements a series of methods, referred to as the modelling interface. These methods are used by the program to exchange information between adjacent models. Traffic controllers

Governing human-environmental ecosystems is a complex problem. Rule-based fisheries models are faced with several challenges. First, for large geographical problems like oceans, they require considerable time to find satisfactory solutions. Second, they tend to be reactive rather than anticipatory. Behavioural assumptions directly impact fishers’ capacity for adaptation and behaviour, which influences

Discrete Event Simulation (DES) is the main tool used in analyzing supply chains (SCs). In many simulation studies the effect of the modeling approach on SC performance is ignored. Many researches have overlooked the fact that in DES where events are the drivers of variable changes; the modeler has the option to change these variables pre or post delay event occurrence. In SCs this choice is critical

The need for innovative systemic approaches for managing water resources that integrate natural and human dimensions is well established. Although systemic, participatory modelling has been shown to support stakeholder involvement and integrated analysis, the uptake within acrimonious, data-scarce contexts – especially in the developing world – is limited. This study details a process designed to address

ABSTRACT In an early stage of the COVID-19 outbreak, hospitals in England were asked to postpone elective treatments in order to accommodate the expected demand for COVID-19 related admissions. This study aims to forecast the extent to which waiting times could increase as a result of these measures, and estimate the level of effort required to restore performance to pre COVID-19 levels. A time-driven

Percentile is an important risk measure quantifying the stochastic system random behaviours. This paper studies a pooled percentile estimator, which is the sample percentile of detailed simulation outputs after directly pooling independent sample paths together. We derive the asymptotic representation of the pooled percentile estimator and further prove its normality. By comparing with the classical

Conceptual modelling is a continuous and iterative process that is essential for simulation projects. However, it often does not receive due consideration. In this sense, many projects document and/or perform the conceptual modelling without following good practices, which ends up affecting the next stages of the simulation. This work aims to identify the state of the art and patterns of conceptual

ABSTRACT This paper describes a means of rapid assessment and review of simulation modelling through drawing upon the Evidence Framework Approach (EFA). The work described focuses on supporting reviewers of modelling, although the method can also be re-purposed to support modellers in the modelling process. The EFA has been used to review new ideas, several months of work, and several years of work

Mohs Micrographic Surgery (MMS) is a layer-by-layer, skin-saving surgical method for excising skin cancer. The number of excised layers is stochastic, which creates operational challenges for the clinic. We develop a discrete-event simulation of a MMS surgical clinic to investigate how appointment schedules impact clinic operations. The model simulates the patient flow for a single day with physician

Current data-driven traffic prediction models are usually trained with large datasets, e.g., several months of speeds and flows. Such models provide very good fit for ordinary road conditions, but often fail just when they are most needed: when traffic suffers a sudden and significant disruption, e.g., a road incident. In this work, we describe QTIP: a simulation-based framework for quasi-instantaneous

A challenge for investors in P2P lending marketplaces is to find an effective allocation of their funds across different loans by assessing the widespread collapse of lending platforms and each loan’s default risk. This paper investigates risk-averse/risk-tolerant/risk-neutral investors’ and borrowers’ transaction behaviours, as well as P2P lending platforms’ operating mechanism. A Heterogeneous Investors

We discuss the use of formal discrete-event modelling and simulation for networking applications, in particular, for mobile networks and Wireless Sensor Networks (WSN). We show how one can develop discrete-event model libraries based on the DEVS formalism for mobile networks, allowing tracking the users’ upload status in a given area of coverage, while using a non-cooperative algorithm or Coordinated

A scenario-based questionnaire is a survey method that aims to identify the respondents’ decision rules using their responses to a series of scenarios. It is rarely used in agent-based modelling and simulation (ABMS) with most researchers preferring a survey with closed questions as the data collection method. This is particularly true for ABMS studies in agri-food supply chains. In our paper, we design

In view of the phenomenon of the guarantee network formed by the mutual guarantee of Chinese enterprises. First, the mechanism of crisis formation in regional guarantee circles is analysed through the network contagion effect, then the enterprise and guarantee model are constructed using the agent method. Second, the evolution rules of a regional guarantee circle crisis under different situations are

ABSTRACT Modelling has been used extensively by all national governments and the World Health Organisation in deciding on the best strategies to pursue in mitigating the effects of COVID-19. Principally these have been epidemiological models aimed at understanding the spread of the disease and the impacts of different interventions. But a global pandemic generates a large number of problems and questions

This paper studies an important real-life perishable inventory management problem, which has not been properly addressed by the existing research. In the problem setting, a number of agents are renting spaces/shelves from a landlord, the inventory capability of each agent is limited to the rent space, and agents are risk-averse due to their budget. The objective is to maximize the profits of the agents/retailers

The goal of this study is to introduce a new design approach of the EPCglobal network considering activities of actors in a supply chain via agent-based simulation (ABS). The EPCglobal network provides track and trace services of shipments for internal and external subscribers, based on electronic product code (EPC) data generated from radio frequency identification (RFID) tags. To maintain dependable

ABSTRACT Gaming simulations (games) for policy and decision making have been the neglected “sibling” of educational and training games. The latter have experienced a widespread usage by practitioners and researchers, while the former have had limited, yet slowly increasing, adoption by organisations. As a result, various issues developing and using these games remain unaddressed. This includes the

Vehicle sharing systems are becoming increasingly popular. The effectiveness of such systems depends, among other factors, on different strategic and operational management decisions and policies, like the dimension of the fleet or the distribution of vehicles. It is of foremost importance to be able to anticipate and evaluate the potential effects of such strategies before they can be successfully

The academic achievement gap in the United States education system persists despite significant investments and efforts to correct it. Research reveals potential functions – priorities, readiness, expectation and motivation – performed by four stakeholders – students, teachers, schools and parents. A system dynamics simulation is proposed that captures the stakeholders and their functions to facilitate

The rapid decarbonisation of transportation is critical if global efforts to mitigate the worst possible impacts of anthropogenic climate change are to be successful. Transportation is a leading sectoral contributor of greenhouse gas emissions, and demand for transportation continues to grow globally. Alternative fuel vehicles (AFVs) powered by fuels such as electricity, hydrogen, and biofuels promise

Simple models are considered useful for decision making, especially when decisions are made by a group of stakeholders. This paper describes an experimental study that investigates whether the level of model detail affects users’ learning. Our subjects, undergraduate students, were asked to solve a resource utilisation task for an ambulance service problem. They worked in groups under three different

Hospital bed management is crucial to ensure that patients do not have to wait for the right bed for their care. A simulation model has been developed that mimics the bed management rules applied to the Trauma & Orthopaedic wards of a busy Welsh hospital. The model includes forecasting methodologies to predict the number of emergency admissions, split by gender. The model uses near real-time admission

A deterministic Material Flow Analysis (MFA) simulation tool has been developed within Microsoft Excel allowing the user to simply and quickly enter relevant material and logistics data. This data is then processed mathematically stepping through time in user-specified intervals assessing stock levels and vehicle status. The monitoring of the material flow in this manner provides data resolution that

In this paper, we build a System Dynamics simulation model to study the long-term counterintuitive consequences of internationalisation strategies of machinery producers in industrial clusters and proposes an explanation for declusterization. To test this hypothesis, we collected empirical data on declusterization and clusters’ exports towards newly industrialized countries, we formalised our hypotheses

Taxi sharing is an emerging transportation arrangement that helps improve the passengers’ travel efficiency and reduce costs. This study analyzes the simulations for an urban taxi sharing system on routes and passengers. Considering the impact of different congestion levels, the relationships between the congestion and cost are analyzed. Under the constraints of the number of passengers and their own

Increase of the computing power on handheld devices has made these devices attractive for many applications including simulation systems. There are Parallel Discrete-Event Simulation (PDES) frameworks exists but most of these are designed for cluster systems, not suitable for battery operated devices. In this paper, the well- known Rensselaer’s Optimistic Simulation System (ROSS) framework has been

Transportation planning is necessary to meet the demand of a given region considering the dimensions of urban space and the complexity of the activities developed on it. In addition to planning, the government intervention through policies to provide an adequate flow of people and goods to meet population demand is also important. In Brazil, the Brazilian Urban Mobility Policy (BUMP) aims to integrate

This paper addresses the problem of Fault Classification and Prediction (FCP) without sufficient data in aircraft maintenance. An innovative approach based on Agent-Based Simulation System (ABSS) and the Fuzzy-Rough Nearest Neighbour (FRNN) method is proposed. To do so, a framework for integrating the FRNN approach into ABSS is firstly provided. The concept and architecture models of FRNN-ABSS are

Stochastic simulation of chemical reactions and diffusion in a neuron helps to provide a realistic view of the molecular dynamics within a neuron. We developed a multi-threaded PDES simulator, Neuron Time Warp-Multi Thread, suitable for the stochastic simulation of reaction and diffusion in a neuron. In this paper we make use of Q-Learning and Simulated Annealing to determine the parameters for a dynamic

Going from a neighbourhood-based to a choice-based system of school selection can have positive effects on enrolment in higher achievement schools, increasing average student achievement. We develop an Agent-Based model (ABM) that simulates students’ decisions on a heterogeneous agents’ framework with information asymmetries between income levels, allowing to simulate school choice policies and determine

The capacitated location routing problem (CLRP) integrates a facility location problem with a multi-depot vehicle routing problem. We consider the CLRP with stochastic demands, whose specific values are only revealed upon reaching each customer. The main goal is to minimise the expected costs of: (i) opening facilities, (ii) using a fleet of vehicles, (iii) executing a routing plan, and (iv) applying

In recent months, we are witnessing a global demonstration of people, predominantly young, spreading a clear message: “we must do something against climate change and do it immediately, the way we live is no longer sustainable”. Despite the urgency of the actions most of the people are not expert in sustainability, thus it is not always trivial to identify the effectiveness of any action, promoted

Recognised as an important concern in mobile, cloud, and high performance computing, the power and energy consumed by computing applications is growing in importance across an increasingly broad range of areas. The importance of this topic to the modelling and simulation community is discussed. Key underlying concepts concerning power and energy consumption are presented. A roadmap for research in

In this paper, a modelling approach is proposed in order to simulate platoon planning possibilities for individual trucks. An agent-based simulation model has been developed using a generic transport network with randomly generated transports in order to calculate potential waiting times of trucks for platooning possibilities. As expected, results show that waiting times decline when the number of

Industrial companies need to measure, evaluate and predict their energy demand to use this knowledge to improve plant control and achieve further energy efficiency. Within the framework of contribution, two model cases from the food and plastic sector are described, which implement the concepts of a “smart consumer” with the focus on demand-side management and smart control approaches. Simulations

Offshore wind turbines are exposed to harsh maritime conditions. This makes the planning of the maintenance processes more challenging and therefore cost-intensive compared to onshore wind turbines. To deal with these challenges, it is important to investigate the impact of different maintenance strategies, e.g. reactive and predictive maintenance on the turbines’ performance. In this context, the

In order to mitigate the unsuccessful subscription of crowdfunding projects, it is critical for the fundraisers to understand various factors and dynamic behaviours affecting the adoption of crowdfunding projects. This study aims to forecast the adoption rate by understanding the underlying preferences of individual customers which is adjusted to their perceived risk and social forces influencing their

The purpose of this study is to identify the issues related to implementation process of “European Agreement on the International Transport of Dangerous Goods by Road (ADR)” regulations in Turkey over a system dynamics model. The proposed model is used for assessing potential impacts of relevant regulations on dangerous goods transportation sector, in terms of road safety, operational effects, and

The Danish government has produced a public document to announce that deviations from societal values were tolerated no more. They denounced the presence of “alternative values” areas (called “parallel societies”), located mostly where low or no income residents live in social/public housing (officially called “ghetto areas” or ghettoområder). Through the means of agent-based computational simulation

ABSTRACT Generic simulation models are designed to enable model reuse. We argue that there are two weaknesses within the generic simulation modelling literature. Firstly, that generic models sacrifice the relative simplicity of a bespoke simulation model for flexibility. Secondly, that generic models are published in conceptual form only. If researchers cannot access computer implementation of models

The problem of managing effective pedestrian evacuation during disruptions is a significant challenge because of the complexity and randomness of the passenger flow dynamics as well as the difficulty in predicting the responsive behaviour of the passengers. In this study, a hybrid agent-based and discrete-event simulation model of passenger flow is designed and implemented to assess the service level

Today natural water resources are becoming scarce, both due to global climate change but also due to irresponsible behaviour of human beings. Lakes are among the most delicate aquatic systems due to their limited size. The objective of this paper is to propose a System Dynamics model, employed in a real case study regarding the city of Rome and one of its water reserves, the Bracciano Lake, for the

This paper describes how last mile deliveries can be considered in a supply chain simulation using distance metrics. A brief overview of urban morphologies and their characteristics will be presented, with a focus on traffic-relevant characteristics. Also, different distance metrics are investigated with respect to their suitability for urban logistics. After a short characterisation, common distance

Degrowth is most commonly defined as a socially sustainable and equitable reduction (and eventually stabilisation) of society’s throughput. Throughput refers to the materials and energy that society extracts, processes, transports, and distributes, in order to consume and return back to the environment as waste. This paper builds on well-established ideas of the degrowth community and explores policy

The management of heterogeneous magnetic resonance imaging (MRI) machines involves a set of complex processes, which encompass multiple examination types, different machine functionalities, and patient priorities. We design three types of rules for task assignment, patient scheduling, and appointment duration in heterogeneous MRI facilities with the consideration of patient priorities to increase system

What is the future trend of gender (dis)parity in the U.S. higher education and workforce populations? I take a systems approach to develop a dynamic simulation model of gender diversity in U.S. higher education. The model consists of an education pipeline for males and females and includes several mechanisms that reinforce interest in higher education or affect university admission or dropout rates

Elevator planning is a key factor for high-rise building construction and building design. Up-peak load is a common phenomenon in building elevator design and operation. For example, in the morning, passengers want to take an elevator to their working floors. Up-peak is often used as the critical traffic period for elevator planning in a building. Two parameters are usually used to plan elevators:

Multi-agent systems are widely used in implementing systems with autonomous behaviour, as well as simulating models that involve human behaviour. Ethical decision-making is a unique aspect of such socio-cognitive systems. In situations that require deliberation over a multitude of options with ethical implications, moral dilemmas are often resolved by a range of heuristics and principles that view