Engineering Coordination: A Methodology for the Coordination of Planning Systems

The reuse of code and concepts is an important aspect when developing multiagent systems (MAS) and it is a driving force of agent-oriented software engineering (AOSE). In particular, the reuse of mechanisms like coordination is fundamental to support developers of MASs. In this article we address the selection of effective and efficient mechanisms to coordinate plans among autonomous agents. The selection of coordination mechanisms is, up to now, not covered sufficiently. Therefore, we present the ECo-CoPS approach that defines a structured process for the selection of coordination mechanisms for autonomous planning systems, where the local autonomy and existing planning systems can be preserve

Engineering coordination : eine Methodologie für die Koordination von Planungssystemen

Planning problems, like real-world planning and scheduling problems, are complex tasks. As an efficient strategy for handing such problems is the ‘divide and conquer’ strategy has been identified. Each sub problem is then solved independently. Typically the sub problems are solved in a linear way. This approach enables the generation of sub-optimal plans for a number of real world problems. Today, this approach is widely accepted and has been established e.g. in the organizational structure of companies. But existing interdependencies between the sub problems are not sufficiently regarded, as each problem are solved sequentially and no feedback information is given. The field of coordination has been covered by a number of academic fields, like the distributed artificial intelligence, economics or game theory. An important result is, that there exist no method that leads to optimal results in any given coordination problem. Consequently, a suitable coordination mechanism has to be identified for each single coordination problem. Up to now, there exists no process for the selection of a coordination mechanism, neither in the engineering of distributed systems nor in agent oriented software engineering. Within the scope of this work the ECo process is presented, that address exactly this selection problem. The Eco process contains the following five steps. • Modeling of the coordination problem • Defining the coordination requirements • Selection / Design of the coordination mechanism • Implementation • Evaluation Each of these steps is detailed in the thesis. The modeling has to be done to enable a systemic analysis of the coordination problem. Coordination mechanisms have to respect the given situation and the context in which the coordination has to be done. The requirements imposed by the context of the coordination problem are formalized in the coordination requirements. The selection process is driven by these coordination requirements. Using the requirements as a distinction for the selection of a coordination mechanism is a central aspect of this thesis. Additionally these requirements can be used for documentation of design decisions. Therefore, it is reasonable to annotate the coordination mechanisms with the coordination requirements they fulfill and fail to ease the selection process, for a given situation. For that reason we present a new classification scheme for coordination methods within this thesis that classifies existing coordination methods according to a set of criteria that has been identified as important for the distinction between different coordination methods. The implementation phase of the ECo process is supported by the CoPS process and CoPS framework that has been developed within this thesis, as well. The CoPS process structures the design making that has to be done during the implementation phase. The CoPS framework provides a set of basic features software agents need for realizing the selected coordination method. Within the CoPS process techniques are presented for the design and implementation of conversations between agents that can be applied not only within the context of the coordination of planning systems, but for multiagent systems in general. The ECo-CoPS approach has been successfully validated in two case studies from the logistic domain.Reale Planungsprobleme, wie etwa die Produktionsplanung in einer Supply Chain, sind komplex Planungsprobleme. Eine übliche Strategie derart komplexen Problemen zu lösen, ist es diese Probleme in einfachere Teilprobleme zu zerlegen und diese dann separat, meist sequentiell, zu lösen (divide-and-conquer Strategie). Dieser Ansatz erlaubt die Erstellung von (suboptimalen) Plänen für eine Reihe von realen Anwendungen, und ist heute in den Organisationsstrukturen von größeren Unternehmen institutionalisiert worden. Allerdings werden Abhängigkeiten zwischen den Teilproblemen nicht ausreichend berücksichtigt, da die Partialprobleme sequentiell ohne Feedback gelöst werden. Die erstellten Teillösungen müssen deswegen oft nachträglich koordiniert werden. Das Gebiet der Koordination wird in verschiedenen Forschungsgebieten, wie etwa der verteilten Künstlichen Intelligenz, den Wirtschaftswissenschaften oder der Spieltheorie untersucht. Ein zentrales Ergebnis dieser Forschung ist, dass es keinen für alle Situationen geeigneten Koordinationsmechanismus gibt. Es stellt sich also die Aufgabe aus den zahlreichen vorgeschlagenen Koordinationsmechanismen eine Auswahl zu treffen, die für die aktuelle Situation den geeigneten Mechanismus identifiziert. Für die Auswahl eines solchen Mechanismus existiert bisher jedoch kein strukturiertes Verfahren für die Entwicklung von verteilten Systems und insbesondere im Bereich der Agenten orientierter Softwareentwicklung. Im Rahmen dieser Arbeit wird genau hierfür ein Verfahren vorgestellt, der ECo-Prozess. Mit Hilfe dieses Prozesses wird der Auswahlprozess in die folgenden Schritte eingeteilt: • Modellierung der Problemstellung und des relevante Kontextes • Formulierung von Anforderungen an einen Koordinationsmechanismus (coordination requirements) • Auswahl/Entwurf eines Koordinationsmechanismuses • Implementierung des Koordinationsverfahrens • Evaluation des Koordinationsverfahrens Diese Schritte werden im Rahmen der vorliegenden Arbeit detailliert beschrieben. Die Modellierung der Problemstellung stellt dabei den ersten Schritt dar, um die Problemstellung analytisch zugänglich zu machen. Koordinationsverfahren müssen die Gegebenheiten, den Kontext und die Domäne, in der sie angewendet werden sollen hinreichend berücksichtigen um anwendbar zu sein. Dieses kann über Anforderungen an den Koordinationsprozess formalisiert werden. Der von den Anforderungen getrieben Auswahlprozess ist ein Kernstück der hier vorgestellten Arbeit. Durch die Formulierung der Anforderungen und der Annotation eines Koordinationsmechanismus bezüglich der erfüllten und nicht erfüllten Anforderungen werden die Motive für Designentscheidungen dieses Verfahren expliziert. Wenn Koordinationsverfahren anhand dieser Anforderungen klassifiziert werden können, ist es weiterhin möglich den Auswahlprozess (unabhängig vom ECo-Ansatz) zu vereinfachen und zu beschleunigen. Im Rahmen dieser Arbeit wird eine Klassifikation von Koordinationsansätzen anhand von allgemeinen Kriterien vorgestellt, die die Identifikation von geeigneten Kandidaten erleichtern. Diese Kandidaten können dann detaillierter untersucht werden. Dies wurde in den vorgestellten Fallstudien erfolgreich demonstriert. Für die Unterstützung der Implementierung eines Koordinationsansatzes wird in dieser Arbeit zusätzlich der CoPS Prozess vorgeschlagen. Der CoPS Prozess erlaubt einen ganzheitlichen systematischen Ansatz für den Entwurf und die Implementierung eines Koordinationsverfahrens. Unterstürzt wird der CoPS Prozess durch das CoPS Framework, das die Implementierung erleichtert, indem es als eine Plattform mit Basisfunktionalität eines Agenten bereitstellt, der für die Koordination von Planungssystemen verantwortlich ist. Im Rahmen des CoPS Verfahrens werden Techniken für den Entwurf und die Implementierung von Konversation im Kontext des agenten-orientiertem Software Engineerings ausführlich behandelt. Der Entwurf von Konversationen geht dabei weit über Fragestellung der Formatierung von Nachrichten hinaus, wie dies etwa in den FIPA Standards geregelt ist, und ist für die Implementierung von agentenbasierten Systemen im Allgemeinen von Bedeutung. Die Funktionsweise des ECo-CoPS Ansatzes wird anhand von zweierfolgreich durchgeführten Fallstudien aus dem betriebswirtschaftlichen Kontext vorgestellt

A meso-level empirical validation approach for agent-based computational economic models drawing on micro-data: a use case with a mobility mode-choice model

The complex nature of agent-based modeling may reveal more descriptive accuracy than analytical tractability. That leads to an additional layer of methodological issues regarding empirical validation, which is an ongoing challenge. This paper offers a replicable method to empirically validate agent-based models, a specific indicator of “goodness-of-validation” and its statistical distribution, leading to a statistical test in some way comparable to the p value. The method involves an unsupervised machine learning algorithm hinging on cluster analysis. It clusters the ex-post behavior of real and artificial individuals to create meso-level behavioral patterns. By comparing the balanced composition of real and artificial agents among clusters, it produces a validation score in [0, 1] which can be judged thanks to its statistical distribution. In synthesis, it is argued that an agent-based model can be initialized at the micro-level, calibrated at the macro-level, and validated at the meso-level with the same data set. As a case study, we build and use a mobility mode-choice model by configuring an agent-based simulation platform called BedDeM. We cluster the choice behavior of real and artificial individuals with the same ex-ante given characteristics. We analyze these clusters’ similarity to understand whether the model-generated data contain observationally equivalent behavioral patterns as the real data. The model is validated with a specific score of 0.27, which is better than about 95% of all possible scores that the indicator can produce. By drawing lessons from this example, we provide advice for researchers to validate their models if they have access to micro-data

Optimierung des Energieverbrauchs bei mobilen Applikationen

Entwickler von mobilen Applikationen wissen nach der Lektüre dieser Bachelorarbeit, wie sie die Energieeffizienz einer App maximieren können. Es werden konkrete Handlungsempfehlungen gegeben, wie rechen- oder kommunikationsintensive Applikationen optimiert werden können, um die Akkulaufzeit zu erhöhen

People-centric policies for decarbonization: Testing psycho-socio-economic approaches by an agent-based model of heterogeneous mobility demand

Decarbonization has become a crucial issue for all countries in the world, which have varied targets and strategies to deal with it, especially after the Paris Agreement. Around one-fifth of global carbon-dioxide emissions is originated from the transportation sector. Policy changes and new regulations are planned to reduce such emissions e.g. by reducing the use of fossil-fuel private cars. For railways, supply-side policies involving large scale and long-term investment have dominated the debate. In this paper, we focus on people-centric policies that could be, in principle, faster and less expensive. To test the potential success of mobilizing demand for low carbon solutions, we have been developing an agent-based computational economics (ACE) model for many modal choices (including railway, bikes, private cars, etc.). It contains a large number of agents, with realistic operative parameters, environment, and infrastructure, reflecting in this study the Swiss system. In this paper, we focus on the railway system. A description of the Swiss world-class railway system is presented and the dynamics in the model, covering the demand for railway mobility as derived from psycho-social-economic approaches, are explored. Innovations in preferences, emotional attitudes and innovative swaps in non-technological resource shift the simulated use of the railway system. Carbon-dioxide direct emission levels are computed. Dynamic and heterogeneous demands of the agents are investigated along with several scenarios, some of them lead to significant decarbonization. We argue, after the simulation results, that railway demand increase can contribute to decarbonization strategies, including those possibly included in the next wave of Nationally Determined Contributions under the Paris Agreement. However, total decarbonization of the transport system will need to embrace further modes, such as e-vehicles and non-motorized transport

Towards ML-based Platforms in Finance Industry – An ML Approach to Generate Corporate Bankruptcy Probabilities based on Annual Financial Statements

The increasing interest in Machine Learning (ML) based services and the need for more intelligent and automated processes in the finance industry brings new challenges and requires practitioners and academics to design, develop, and maintain new ML approaches for financial services companies. The main objective of this paper is to provide a standardized procedure to deal with cases that suffer from imbalanced datasets. For this, we propose design recommendations on, how to test and combine multiple oversampling techniques such as SMOTE, SMOTE-ENN and SMOTE-Tomek on such datasets with multiple ML models and attribute-based structure to reach higher accuracies. Moreover, this paper considers to find an appropriate structure while maintaining such systems that work with periodically changing datasets, so that the incoming datasets can be analyzed regularly via this procedure

Hydropower Operation in a Changing Market Environment – A Swiss Case Study

Hydropower (HP) is expected to play an important role in the European energy transition by providing back-up and storage capacity as well as flexibility for intermittent renewable energies. However, due to low electricity market prices the profitability of HP decreased in recent years. In this paper, we analyze historic revenue potentials and future market prospects for HP taking into account different development paths. Using a short-term HP operation model to capture market opportunities as well as technical and natural constraints of HP plants, we model three representative Swiss HP plants. The results indicate that in the last years, balancing markets could have provided significant additional revenues for HP plants. However, accounting for uncertainties and market characteristics, the potential of balancing markets is reduced but cross-market optimization is still beneficial. Looking into the future, market price prospects for the coming decade are low to modest. Global fuel markets and the European Union Emissions Trading System (ETS) will be the main drivers for decisions for Swiss HP. The revenue potential from balancing markets will be reduced significantly in the future if all Swiss HP operators aim for balancing. While optimized operation across markets helps Swiss HP to increase its revenues, it is limited in scale

Beurteilung der Anwendbarkeit vorhandener Web-GIS Module für die Rovina & Partner AG

Im Rahmen dieser Bachelorarbeit für die Rovina & Partner AG werden drei Ziele verfolgt. Der erste Schritt der Arbeit erfordert, dass verschiedene Web-GIS Module im .NET-Bereich beurteilt und miteinander verglichen werden. Anschliessend wird das Modul mit der besten Beurteilung als Entwicklungsgrundlage für die Erstellung eines Web-Geoinformationssystems eingesetzt, was als zweites Ziel der Arbeit gilt. Zum Schluss soll das System in die ITInfrastruktur der Unternehmung integriert werden

Self- and Peer Assessment Tool: Die Entwicklung eines Webapplikationsprototypen auf dem Prinzip des Self- and Peer Assessments Student

Das Ziel der vorliegenden Bachelorarbeit ist die Erstellung eines Prototyps für ein Self- and Peer Assessment. Der Prototyp ist in Zusammenarbeit mit Herrn Thomas Tribelhorn, Leiter des Bereiches Hochschuldidaktik und Lehrentwicklung der Universität Bern, realisiert worden. Von Seiten des Auftraggebers soll der Prototyp auf dem Prinzip des Self- and Peer Assessments beruhen. Das Prinzip des Self- and Peer Assessments findet heute Anwendung in Universitäten, Fachhochschulen oder in der Personalaus- und Weiterbildung. Die Namensgebung des Prototypen SEPAT setzt sich zusammen aus der abgekürzten Version von Self- and Peer Assessment Tool

The Future of Swiss Hydropower A Review on Drivers and Uncertainties

Swiss Hydropower (HP) is currently facing a wide range of challenges that have initiated a debate about future prospects and its role within the envisioned energy transition. Building on this debate, this paper provides an overview of the status and prospects of Swiss HP by identifying and evaluating the different drivers and uncertainties that Swiss HP faces. Based on a review and the perceptions held by some of the main Swiss HP stakeholders the two main topics that need to be addressed are the market driven impacts and the political, legal and social aspects. While the market dynamics cannot directly be influenced by Swiss companies or authorities, the regulatory framework can and needs to be adjusted. However, this requires a comprehensive stakeholder process and is at least a medium-term process