18 research outputs found

    Theory Development through Simulation: Extending coordination theory in crisis response

    Get PDF
    As a research method, simulation can be useful in coping with the lack of data or in designing experiments that would be too costly or risky otherwise. This is especially relevant in the domain of crisis response, where on top of the difficulty of controlling data gathering and experiments there is also a lack of theory, particularly in terms of coordination. We present a framework that guides the use of simulation as a method for theory development in this domain. We illustrate this framework with research in progress aimed at extending the theory of coordination in crisis response. A simulation model is built to operationalize the theory and enable improved understanding of coordination in crisis response

    Collaborative, Distributed Simulations of Agri-Food Supply Chains. Analysis on How Linking Theory and Practice by Using Multi-agent Structures

    Get PDF
    Simulations help to understand and predict the behaviour of complex phenomena’s, likewise distributed socio-technical systems or how stakeholders interacts in complex domains. Such domains are normally based on networked based interaction, where information, product and decision flows comes in to play, especially under the well-known supply chains structures. Although tools exist to simulate supply chains, they do not adequately support multiple stakeholders to collaboratively create and explore a variety of decision-making scenarios. Hence, in order to provide a preliminary understanding on how these interaction affects stakeholders decision-making, this research presents an study, analysis and proposal development of robust platform to collaboratively build and simulate communication among supply chain. Since realistic supply chain behaviours are complex, a multi-agent approach was selected in order to represent such complexities in a standardised manner. The platform provides agent behaviours for common agent patterns. It provides extension hotspots to implement more specific agent behaviour for expert users (that requires programming). Therefore, as key contribution, technical aspects of the platform are presented, and also the role of multi-level supply chain scenario simulation is discussed and analysed, especially under de context of digital supply chain transformation in the agri-food context. Finally, we discuss lessons learned from early tests with the reference implementation of the platform

    A platform-independent model for agents

    Get PDF
    Various agent-oriented methodologies and metamodels exist to describe multiagent systems ([VIAS) in an abstract manner. Frequently, these frameworks specialize on particular parts of the MAS and only few works have been invested to derive a common standardization. This limits t he impact of agent-related systems in commercial applications. In this paper, we present a metamodel for agent systems that abstract from existing agent-oriented methodologies and platforms and could thus be called platform-independent. This metamodel provides the core language that is used in our agentoriented software development process that conforms to the principles of Model-Driven Developrnent (MDD). Beside the domain-specific modelling language, we further provide two model transformations that allow to transform the generated models into textual code that call be executed with JACK and JADE

    Collaborative, Distributed Simulations of Agri-Food Supply Chains : Analysis on How Linking Theory and Practice by Using Multi-agent Structures

    Get PDF
    Simulations help to understand and predict the behaviour of complex phenomena's, likewise distributed socio-technical systems or how stakeholders interacts in complex domains. Such domains are normally based on networked based interaction, where information, product and decision flows comes in to play, especially under the well-known supply chains structures. Although tools exist to simulate supply chains, they do not adequately support multiple stakeholders to collaboratively create and explore a variety of decision-making scenarios. Hence, in order to provide a preliminary understanding on how these interaction affects stakeholders decision-making, this research presents an study, analysis and proposal development of robust platform to collaboratively build and simulate communication among supply chain. Since realistic supply chain behaviours are complex, a multi-agent approach was selected in order to represent such complexities in a standardised manner. The platform provides agent behaviours for common agent patterns. It provides extension hotspots to implement more specific agent behaviour for expert users (that requires programming). Therefore, as key contribution, technical aspects of the platform are presented, and also the role of multi-level supply chain scenario simulation is discussed and analysed, especially under de context of digital supply chain transformation in the agri-food context. Finally, we discuss lessons learned from early tests with the reference implementation of the platform.Laboratorio de Investigación y Formación en Informática Avanzad

    Designing a multi-agent system for monitoring and operations recovery for an airline operations control centre

    Get PDF
    A operação de uma companhia área raramente acontece como planeado. São comuns os problemas relacionados com os aviões, com as tripulações e com os passageiros. As acções que têm como objectivo resolver estes problemas são conhecidas como Gestão das Irregularidades Operacionais. O Centro de Controlo Operacional da Companhia Aérea (CCO) tenta resolver estes problemas com o mínimo de impacto na operação, com o mínimo custo e, ao mesmo tempo, satisfazendo todas as regras de segurança requeridas. Normalmente, cada problema é tratado separadamente e algumas ferramentas têm sido propostas para ajudar no processo de tomada de decisão pelos coordenadores destes centros de controlo. Observamos o CCO da TAP Portugal, a maior companhia aérea Portuguesa, e, destas observações, várias hipóteses foram identificadas e algumas experimentadas. Acreditamos, e esta é uma das nossas principais hipóteses, que o paradigma do Sistema Multi-Agente (SMA) é mais adequado para representar a organização hierárquica de vários níveis e as várias funções (roles) existentes no CCO. Nesta tese, propomos o desenho e a implementação parcial de um SMA Distribuído que represente as várias funções existentes no CCO. Admitimos a hipótese de que, tirando partido do facto de que cada base operacional tem recursos específicos (quer aviões quer tripulantes) e juntando informações que digam respeito aos custos envolvidos (por exemplo, informação sobre vencimentos dos tripulantes, custos dos hotéis, entre outros), as soluções para os problemas detectados serão encontradas mais rapidamente e serão menos caras. Também admitimos a hipótese de que se utilizarmos agentes de software especializados que implementam diferentes soluções (heurísticas e outras soluções baseadas em modelos de investigação operacional e algoritmos de inteligência artificial) aplicadas ao mesmo problema, a robustez do sistema irá aumentar. Finalmente, acreditamos que a inclusão de um mecanismo de aprendizagem, que aprenda com a utilização anterior dos tripulantes, irá aumentar a qualidade das soluções. Estendendo esse mecanismo de forma a aprender o perfil de cada tripulante e aplicando esse conhecimento na geração de planeamentos (escalas) futuros, a gestão deste recurso tão caro será muito mais eficiente e o nível de satisfação de cada tripulante irá aumentar. Apresentamos um caso de estudo real, obtido no CCO da TAP, onde um problema relacionado com tripulantes é resolvido usando o SMA proposto. Apresentamos resultados computacionais, usando uma operação real da companhia aérea, incluindo a comparação com uma solução para o mesmo problema encontrada pelo operador humano do CCO. Mostramos que, mesmo para problemas simples e quando comparado com soluções encontradas por operadores humanos, no caso específico desta companhia aérea, é possível encontrar soluções válidas, em menos tempo e com menos custos.Nesta tese também mostramos como completamos a metodologia GAIA de forma a melhor analisar e desenhar o SMA proposto para o CCO. Para além de mostrarmos o rationale que está por trás da análise, desenho e implementação do nosso sistema, também mostramos como mapeamos as abstracções usadas no desenho orientado a agentes para código específico em JADE. As vantagens da utilização de uma análise de requisitos orientada a objectivos e a sua influência nas fases seguintes da análise e do desenho, também são apresentadas. Finalmente, propomos diagramas UML 2.0 para representação de vários deliverables da GAIA, tais como, estrutura organizacional, modelos de funções (role) e de interacções e modelos de agentes e de serviços.An airline schedule seldom operates as planned. Problems related with aircrafts, crew members and passengers are common and the actions towards the solution of these problems are usually known as operations recovery or disruption management. The Airline Operations Control Center (AOCC) tries to solve these problems with the minimum impact in the airline schedule, with the minimum cost and, at the same time, satisfying all the required safety rules. Usually, each problem is treated separately and some tools have been proposed to help in the decision making process of the airline coordinators. We have observed the AOCC of TAP Portugal, the major Portuguese airline, and, from those observations, several hypotheses have been identified and some of them experimented. We believe, and that is one of our main hypothesis, that the Multi-Agent System (MAS) paradigm is more adequate to represent the multi-level hierarchy organization and the several roles that are played in an AOCC. In this thesis we propose the design and partial implementation of a Distributed MAS representing the existing roles in an AOCC. We hypothesize that if we take advantage of the fact that each operational base has specific resources (both crew and aircrafts) and that if we include information regarding costs involved (for example, crew payroll information and hotels costs, among others), the solutions to the detected problems will be faster to find and less expensive. We also hypothesize that if we use specialized software agents that implement different solutions (heuristic and other solutions based in operations research models and artificial intelligence algorithms), to the same problem, the robustness of the system will increase. Finally, we believe that the inclusion of some kind of learning mechanism that learns from previous utilization of crew members will improve the solutions quality. Extending that learning mechanism to learn each crew member profile, and applying that knowledge for generating future schedules, the management of that expensive resource will be much more efficient and the level of satisfaction of each crew member will increase. We also present a real case study taken from TAP Portugal AOCC, where a crew recovery problem is solved using the MAS. Computational results using a real airline schedule are presented, including a comparison with a solution for the same problem found by the human operators in the Airline Operations Control Center. We show that, even for simple problems, and when comparing with solutions found by human operators in the case of this airline company, it is possible to find valid solutions, in less time and with a smaller cost. In this thesis we also show how we complement the GAIA methodology in order to better analyze and design the proposed MAS for the AOCC. Besides showing the rationale behind the analysis, design and implementation of our system, we also present how we mapped the abstractions used in agent-oriented design to specific constructs in JADE. The advantages of using a goal-oriented early requirements analysis and its influence on subsequent phases of analysis and design are also presented. Finally, we also propose UML 2.0 diagrams at several different levels for representation of GAIA deliverables, like organizational structure, role and interaction model, agent and service model

    Embedding smart software agents in resource constrained Internet of Things devices

    Get PDF
    [ES]Los sistemas de sensorización en combinación con herramientas de tratamiento y gestión inteligente de información, constituyen la base sobre la que se construirán las ciudades y entornos urbanos del futuro. Avanzar en la investigación y desarrollo de estos nuevos escenarios inteligentes, es fundamental a la hora de alcanzar los objetivos de eficiencia, integración, sostenibilidad y calidad de vida de las personas que habitan nuestras ciudades. Para alcanzar estos objetivos, es fundamental indagar en el desarrollo de dispositivos hardware más baratos, precisos e inteligentes que serán la base de los entornos inteligentes del futuro. Debido a las previsiones realizadas para los próximos años, la cantidad de dispositivos conectados a Internet será de hasta 7 dispositivos por cada persona en el planeta. Esta avalancha de dispositivos llevará asociada una avalancha de datos que tendrán que ser manejados y almacenados por los centros de procesamiento de datos. Por todo ello, avanzar en el diseño de herramientas para el procesamiento de datos inteligente, así como en nuevos dispositivos de sensorización, es una tarea de vital importancia para la viabilidad futura de los entornos conectados. Por ello, en este trabajo de tesis doctoral se propone un sistema inteligente basado en agentes embebidos en dispositivos inalámbricos con capacidades reducidas (memoria y capacidad de cómputo limitada), para entornos del Internet de las cosas (IoT) donde sea posible un procesamiento inteligente de datos. En particular, se presenta una novedosa arquitectura multi-agente enfocada a la gestión de los datos generados por los dispositivos IoT, sobre la que construir una capa de servicios adaptada a las diferentes necesidades de los distintos entornos donde será posible desplegar el sistema de sensorización. Con el objetivo de validad el sistema propuesto, se ha diseñado un caso de estudio basado en redes de sensores en un entorno IoT de eficiencia energética a través de la optimización del consumo de batería de una bicicleta eléctrica

    Requirements Modeling for Multi-Agent Systems

    Get PDF
    Different approaches for building modern software systems in complex and open environments have been proposed in the last few years. Some efforts try to take advantage of the agent-oriented paradigm to model/engineer complex information systems in terms of independent agents. These agents may collaborate in a computational organization (Multi-Agent Systems, MAS) by playing some specific roles having to interact with others in order to reach a global or individual goal. In addition, due to the complex nature of this type of systems, dealing with the classical functional and structural perspectives of software systems are not enough. The organizational perspective, that describes the context where these agents need to collaborate, and the social behavior perspective, that describes the different "intelligent" manners in which these agents can collaborate, need to be identified and properly specified. Several methodologies have been proposed to drive the development of MAS (e.g., Ingenias, Gaia, Tropos) although most of them mainly focus on the design and implementation phases and do not provide adequate mechanisms for capturing, defining, and specifying software requirements. Poor requirements engineering is recognized as the root of most errors in current software development projects, and as a means for improving the quality of current practices in the development of MAS, the main objective of this work is to propose a requirements modeling process to deal with software requirements covering the functional, structural, organizational, and social behavior perspectives of MAS. The requirements modeling proposed is developed within the model-driven engineering context defining the corresponding metamodel and its graphical syntax. In addition, a MAS requirements modeling process is specified using the Object Management Group's (OMG) Software Process Engineering Metamodel (SPEM). Finally, in order to illustrate the feasibility of our approach, we specified the software requirements of a strategic board game (the Diplomacy game).Rodríguez Viruel, ML. (2011). Requirements Modeling for Multi-Agent Systems. http://hdl.handle.net/10251/11416Archivo delegad

    Process control and configuration of a reconfigurable production system using a multi-agent software system

    Get PDF
    Thesis (M. Tech. (Information Technology)) -- Central University of technology, Free State, 2011Traditional designs for component-handling platforms are rigidly linked to the product being produced. Control and monitoring methods for these platforms consist of various proprietary hardware controllers containing the control logic for the production process. Should the configuration of the component handling platform change, the controllers need to be taken offline and reprogrammed to take the changes into account. The current thinking in component-handling system design is the notion of re-configurability. Reconfigurability means that with minimum or no downtime the system can be adapted to produce another product type or overcome a device failure. The re-configurable component handling platform is built-up from groups of independent devices. These groups or cells are each responsible for some aspect of the overall production process. By moving or swopping different versions of these cells within the component-handling platform, re-configurability is achieved. Such a dynamic system requires a flexible communications platform and high-level software control architecture to accommodate the reconfigurable nature of the system. This work represents the design and testing of the core of a re-configurable production control software platform. Multiple software components work together to control and monitor a re-configurable component handling platform. The design and implementation of a production database, production ontology, communications architecture and the core multi-agent control application linking all these components together is presented

    A model-driven approach for organizations in multiagent systems

    Get PDF
    This thesis introduces a new model-driven approach to agent-oriented software engineering in which agent organizations not only play a crucial role, but are also represented in every abstraction level. In our methodology, multiagent systems are modeled at a platform-independent level and transformed into a platform-specific level preserving the organizational structures. The approach has been refined through several years and has been used in two European Union projects.In dieser Arbeit wird ein neuer Modell-basierter Ansatz für die Agentenorientierte Softwaretechnik vorgestellt, bei dem Agenten-Organisationen nicht nur eine entscheidende Rolle spielen, sondern auch auf allen Abstraktionsebenen vertreten sind. In der dargestellten Methodik werden Multiagenten-Systeme auf einer Plattform-unabhängigen Ebene modelliert und dann in ein Plattform-spezifisches Modell umgewandelt, wobei die Organisationsstrukturen erhalten bleiben. Der Ansatz wurde über einige Jahre kontinuierlich verfeinert und bereits in zwei Projekten der Europäischen Union implementiert
    corecore