Modelling office energy consumption: an agent based approach

In this paper, we develop an agent-based model which integrates four important elements, i.e. organisational energy management policies/regulations, energy management technologies, electric appliances and equipment, and human behaviour, based on a case study, to simulate the energy consumption in office buildings. With the model, we test the effectiveness of different energy management strategies, and solve practical office energy consumption problems. This paper theoretically contributes to an integration of four elements involved in the complex organisational issue of office energy consumption, and practically contributes to an application of agent-based approach for office building energy consumption study

Modelling office energy consumption: an agent based approach

In this paper, we develop an agent-based model which integrates four important elements, i.e. organisational energy management policies/regulations, energy management technologies, electric appliances and equipment, and human behaviour, based on a case study, to simulate the energy consumption in office buildings. With the model, we test the effectiveness of different energy management strategies, and solve practical office energy consumption problems. This paper theoretically contributes to an integration of four elements involved in the complex organisational issue of office energy consumption, and practically contributes to an application of agent-based approach for office building energy consumption study

Simulating customer experience and word-of-mouth in retail: a case study

Agents offer a new and exciting way of understanding the world of work. In this paper we describe the development of agent-based simulation models, designed to help to understand the relationship between people management practices and retail performance. We report on the current development of our simulation models which includes new features concerning the evolution of customers over time. To test the features we have conducted a series of experiments dealing with customer pool sizes, standard and noise reduction modes, and the spread of customers’ word of mouth. To validate and evaluate our model, we introduce new performance measure specific to retail operations. We show that by varying different parameters in our model we can simulate a range of customer experiences leading to significant differences in performance measures. Ultimately, we are interested in better understanding the impact of changes in staff behavior due to changes in store management practices. Our multi-disciplinary research team draws upon expertise from work psychologists and computer scientists. Despite the fact we are working within a relatively novel and complex domain, it is clear that intelligent agents offer potential for fostering sustainable organizational capabilities in the future

A Discrete Event Simulation of Network Centric Operations: Modeling Unbalanced Combat Configurations in Symmetric Engagements

Network Centric Operations (NCO) has been dubbed the most significant revolution in military affairs (RMA) in the past 200 years. The promise of NCO is based on the notion that information sharing and connectivity is fundamental to the effectiveness of a combat force. This due to the ability of a properly networked force to self-synchronize itself as it engages enemy forces. The purposeful arrangement of assets in a combat force is what makes it \u27properly networked\u27. What is a purposeful arrangement of combat assets? How should a force organize to enhance information sharing and connectivity? And how does connectivity within a networked force impact its combat effectiveness? This research builds a discrete-event simulation of the information age combat model, which is a representation of NCO, in an attempt to understand the impact of information sharing and connectivity among the elements of a military force on its combat effectiveness. Unbalanced combat configurations doing symmetric engagements were selected as the prime focus. They were studied and simulated to gain insights into the dynamics of networked operations. The proposed discrete event combat model displayed significant increases in efficiency and speed of running compared to previous modeling work that utilized agent-directed simulations. Linear and nonlinear regression analyses were conducted to highlight the performance metrics that wield significant predictive power over the probability of winning a combat engagement

Is competition sufficient to drive observed retail location and revenue patterns? An agent-based case study.

Agent-based models (ABMs) have been widely used to represent and investigate complex systems and are a contemporary modelling approach used in the study of land-use and land-cover change. While many ABMs have been constructed to address research questions associated with residential land development and human choices, agricultural land transition and farmer decision-making, and transportation networks and planning, less attention has been given to improving our understanding about the drivers and agent behaviours associated with commercial and retail competition, which subsequently affects land-use change. Among existing ABMs that represent the retail system, the focus has been on understanding consumer behaviours, but the inclusion of the store competition is lacking, and most retail competition models still use a top-down modelling framework. The thesis herein provides a new contribution to retail competition literature through the development and use of a retail-competition agent-based model (RC-ABM). Utilizing previous empirical research on consumer expenditures and retail location site selection, competition for home-improvement expenditures is simulated within the home-improvement retail system in the Region of Waterloo, Ontario, Canada. Results exhibit a high level of alignment between the RC-ABM and a traditional Location-Allocation Model (LAM) in estimating a market capture and store revenue acquisition. In addition, while modelled competition itself cannot reproduce the observed spatial pattern of home-improvement stores in our study area, results from the model can be used to identify path dependencies associated with retail success generated by competition and factors affecting retail store survival. Lastly, the presented RC-ABM provides the potential to enrich future land-use and land-cover change models by better representing commercial development

Strumenti per la simulazione: dal "Discrete Event Simulation" all’“Agent Based Modeling” - Lo stato dell’arte attraverso lo sviluppo di casi reali e la sperimentazione delle nuove metodologie

2010 - 2011Questa tesi presenta un percorso di attività caratterizzato dall’applicazione della simulazione in ambienti produttivi. Viene prima presentato uno studio di ottimizzazione di un impianto di cartotecnica attraverso simulazione DES in ambiente Digital Factory. L’esperienza maturata nella modellazione DES ha permesso di apprezzare i vantaggi di questo tipo di approccio ma anche di individuare i suoi punti deboli. Dal punto di vista della modellazione, DES propone la costruzione del modello attraverso la combinazione di blocchi logici standard predefiniti che riproducono lo schema di flusso del processo. Questo tipo di approccio si adatta bene alla simulazione di sistemi manifatturieri soprattutto se i fattori umani non sono considerati. Lo studio su un caso reale ha evidenziato l’approfondito livello di dettaglio che questo approccio richiedere. Dal punto di vista dell’utilizzatore, questo rappresenta un vantaggio perché aumenta l’accuratezza e la credibilità dei modelli realizzati e quindi delle soluzioni migliorative proposte. Dall’altro però rappresenta un ostacolo poiché rispetto ad altri approcci, DES è decisamente una metodologia “data hungry”. Un altro aspetto importante riguarda la complessità di utilizzo: sebbene negli ultimi anni, alcune società fanno uso di questi tool, quasi sempre si avvalgono di consulenza esterna perché mancano le risorse specializzate per realizzare questo tipo di studio. Inoltre i costi di training sono elevati così come i costi di sviluppo dei modelli. In particolare, questi ultimi sono causati da lunghi tempi di sviluppo dei modelli sia per la complessità computazionale che per procedure di modellazione lunghe e ripetitive. Un’applicazione basata su ACCESS è stata sviluppata per accelerare la fase di costruzione dei modelli e facilitare l’utilizzo agli utenti meno esperti. I risultati, valutati in termini di tempo di modellazione e numero di operazioni elementari realizzate sono stati comparati con la procedura tradizionale del software DES di QUEST. La verifica è stata effettuata attraverso la costruzione di numerosi modelli di impianti produttivi e infine è stato ricostruito il modello della linea rotoli della cartotecnica Confalone. I risultati hanno evidenziato una riduzione del 50% dei tempi di costruzione del modello evidenziando come è possibile facilitare l’utilizzo di tool DES attraverso questo tipo di applicazione. Infine, la tesi ha presentato uno studio di simulazione basato su metodologia ABM per l’analisi di un sistema DRC configurato come una linea di assemblaggio con layout flow-shop. Regole di assegnazione degli operatori sono state implementare per modellare la cosiddetta “workforce flexibility”. L’approccio di modellazione non convenzionale di ABM, seppur non sviluppato specificatamente per sistema produttivi, ha comunque permesso di realizzare un modello ad agenti per una linea di assemblaggio costituita da 8 stazioni di assemblaggio e buffer intermedi. La complessità di modellare le regole di assegnazione degli operatori è venuta meno grazie alla tipologia di costruzione dei sistemi ad agenti. Nel modello infatti sono stati definiti tre tipologie di agenti: agente “Macchina”, agente “Prodotto” e agente “Operatore”. Gli agenti così definiti e inseriti in un ambiente possono scambiare informazioni tra di loro e mostrare un comportamento che scaturisce da regole definite per ognuno di essi. Una campagna di esperimenti (DOE) e un’analisi ANOVA hanno permesso di valutare i risultati del sistema produttivo in termini di prestazioni del sistema e “human effects”.Il modello ABM sviluppato ha permesso di comparare i risultati ottenuti sul sistema di produzione in configurazione DRC con quelli presenti in letteratura. La metodologia ABM ha inoltre mostrato grandi potenzialità nell’integrazione di fattori umani nei processi di ottimizzazione dei sistemi produttivi superando la complessità di programmazione dell’approccio DES. Future applicazioni proveranno ad implementare fattori di fatica nel modello. [a cura dell'autore]X n.s

A simulation approach for modelling and investigation of inventory inaccuracy in warehouse operation

This thesis is focused on a simulation modelling approach to address the inventory inaccuracy problems in a warehouse operation. The main motivation which led to this research was a desire to investigate the inventory inaccuracy issues that have been highlighted by a logistics company. Previous and current research into inventory inaccuracy issues is largely related to the development of RFID technology as a possible solution to inventory problems. Since the inventory inaccuracy related to RFID technology is focused on the overall measurement of inventory management and retail business, there are differences between this existing research and the research presented in this thesis which is focused on issues of inventory inaccuracy in a warehouse operation. In this thesis, warehouse operation is studied as a detailed sequence of processes that are involved in the flow of items physically in parallel with related information being stored in the computer system. In these processes there are many places where errors can occur in counting or recording details of inventory, or in physically moving, storing or picking items incorrectly. These details of a warehouse operation are used to develop a conceptual model of inventory inaccuracy in warehouse operations. The study also found that typically a product needs to be considered differently at different stages of its progress through a warehouse (and therefore within different sections of the conceptual model). This is because initially batches of a product are likely to be delivered from a supplier, therefore if errors occur soon after the product is delivered to the warehouse, the error might involve the whole batch (for example the batch may be misplaced and put in an incorrect storage location), or the error might involve just part of the batch (for example poor transportation by forklift truck may damage the packaging carton and some of the items within the carton). When the product is stored ready for meeting customer orders, it needs to be considered as individual items (and errors can occur in counting of individual items or individual items may be misplaced or stolen). Finally, when a customer order is received, the product will be picked and grouped to meet the requirements of the order (for example, one order may require 10 of the product whilst another order may require 20 of the product). Errors might again occur to the whole group or to just part of the group. (Continued ...