Browsing by Subject "Mehragentensystem"

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Beitrittsentscheidungen zu Multiagenten-Organisationen : ein Revenue Management-basierter Ansatz
(2018) Premm, Marc; Kirn, Stefan
Der Forschungsbereich Multiagentensysteme hat sich seit den späten 1970er Jahren als Teilbereich der verteilten künstlichen Intelligenz (VKI) etabliert. Gegenstand dieses Forschungsbereichs sowie dieser Arbeit sind Softwareagenten, die als Softwaresysteme zielorientiert agieren und mittels Lernverfahren eine gewisse Autonomie gegenüber ihrem Entwickler erlangen. Softwareagenten ist es möglich, sich zu Multiagentensystemen zusammenzuschließen. Multiagentensysteme sind folglich offene Systeme, aus denen Softwareagenten ein- und wieder austreten können – im Allgemeinen ohne globale Kontrolle. Hieraus ergibt sich eine gewisse Flüchtigkeit sowohl der Mitgliedermenge als auch der Interaktionsstrukturen eines Multiagentensystems und somit eine eingeschränkte Möglichkeit zur Steuerung des nach außen hin wahrnehmbaren Systemverhaltens, welcher es beim Einsatz von Softwareagenten in kommerziellen Anwendungen im Allgemeinen bedarf. Multiagenten-Organisationen bilden einen Ansatz um die betriebswirtschaftliche Organisationstheorie zur internen Strukturierung von Multiagentensystemen zu nutzen und folglich auch deren Außenverhalten zielgerichtet zu steuern. Diese Arbeit versteht Multiagenten-Organisationen als auf Dauerhaftigkeit ausgelegte Zusammenschlüsse von mehreren unabhängigen Softwareagenten, die durch vertragliche Regelungen an der Erfüllung eines vorgegebenen Organisationsziels mitwirken. Softwareagenten benötigten Zugriff auf Ressourcen um einerseits bestimmte Dienste anbieten (z.B. Datenbank-Zugriff) aber auch um ihre eigene Ausführung sicherstellen zu können (z.B. Hardwareressourcen). Softwareagenten können die ihnen zur Verfügung stehenden Ressourcen nutzen um einer Multiagenten-Organisation im Rahmen einer Mitgliedschaft Dienste zur Verfügung zu stellen. Die Erbringung von Diensten konsumiert stets einen Teil der einem Softwareagenten zur Verfügung stehenden Ressourcen. Softwareagenten werden daher einer Multiagenten-Organisation Dienste nur gegen eine entsprechende Kompensation zur Verfügung stellen. Der Beitritt eines Softwareagenten zu einer Multiagenten-Organisation ist stets das Ergebnis von Beitrittsverhandlungen zwischen diesen beiden Akteuren, in denen neben den bereitzustellenden Diensten und der zu zahlenden Kompensation, insbesondere die Dienstgüte verhandelt wird. Softwareagenten können dabei Mitglied in mehreren Multiagenten-Organisationen sein. Jeder Softwareagent hat hierbei zu entscheiden, ob bzw. welcher Multiagenten-Organisation er beitritt und in welchem Umfang er die verfügbaren Ressourcen hierfür einsetzt. Dabei hat er bereits bestehende Mitgliedschaften in anderen Multiagenten-Organisationen, für die der Softwareagent bereits Dienste bereitstellt und somit Ressourcen auslastet, bei der Beitrittsentscheidung mit zu berücksichtigen. Hieraus lässt sich folgende Forschungsfrage ableiten: Wie sind Entscheidungsverfahren auszugestalten, die es Softwareagenten ermöglichen, nutzenmaximierende Beitrittsentscheidungen zu Multiagenten-Organisationen zu treffen? Diese Arbeit präsentiert ein Verfahren zur Optimierung von Beitrittsentscheidungen von Softwareagenten zu Multiagenten-Organisationen. Das entwickelte Verfahren basiert auf Ansätzen des Revenue Management als Teilbereich des Operations Research. Die in der Literatur vorhandenen Verfahren des Revenue Management sind dabei nicht in der Lage, die Gegebenheiten von Beitritts-entscheidungen von Softwareagenten abzubilden. Das entwickelte Revenue Management-basierte Modell der Beitrittsentscheidung versetzt Softwareagenten in die Lage Mitgliedschaften in Multiagenten-Organisationen zu bewerten, deren Dauer a-priori unbekannt ist, und potentielle Mitgliedschaften anhand verschiedener Dienstgüteklassen abzugrenzen. Das entwickelte Verfahren nutzt die auf dieser Basis vorhandenen Möglichkeiten der Optimierung von Beitritts¬entscheidungen, greift den Ansatz von Ressourcen-bezogenen Reservationspreisen (so genannten Bid-Prices) aus dem Revenue Management auf und passt diesen auf die Gegebenheit von Beitritts¬entscheidungen von Softwareagenten an. Das entwickelte Verfahren wird durch ein Simulationsexperiment auf ihre Wirksamkeit und die hierfür notwendigen Bedingungen hin evaluiert. Zur Erreichung dieser Ziele wird ein Referenz- Entscheidungsverfahren herangezogen und verschiedene Parameter der Simulation jeweils paarweise variiert. In der Mehrzahl der untersuchten Parameterkonstellationen erzielt das entwickelte Verfahren eine Steigerung der erwirtschafteten Kompensation. Softwareagenten, die in einer Domäne Dienste anbieten, in der diese Parameterkonstellationen vorzufinden sind, werden durch die Anwendung des Verfahrens in die Lage versetzt, höhere Kompensationen durch Mitgliedschaften in Multiagenten-Organisationen zu erzielen als mit dem Referenz-Entscheidungsverfahren. Sind dem Softwareagenten einzelne Parameter a-priori nicht bekannt, kann mit Hilfe dieser simulativen Evaluation bereits das Risiko des Einsatzes des Verfahrens abgeschätzt werden. Das entwickelte Verfahren konnte jedoch nicht für alle Parameterkonstellationen einen Vorteil erwirtschaften, so dass für die Anwendung zwei wesentliche Voraussetzungen zu beachten sind: (1) Differenzierungsmöglichkeiten. Grundvoraussetzung für die Anwendung des Verfahrens ist die Möglichkeit der Differenzierung und den damit verbundenen Unterschieden in der Höhe der erzielten Kompensation bei gleichem Ressourceneinsatz. Diese Differenzierung kann durch verschiedene Maßnahmen des Softwareagenten erreicht werden: (i) Für verschiedene Dienste mit gleichem Ressourcenbedarf werden unterschiedlich hohe Kompensationsforderungen gestellt, (ii) ein oder mehrere Dienste werden in unterschiedlichen Dienstgüteklassen angeboten, deren Kompensationen sich in ausreichendem Maße unterscheiden oder (iii) verschiedene Dienste nutzen eine unterschiedliche Menge an Ressourcen. (2) Nachfrage. Das in dieser Arbeit entwickelte Bid-Price-Verfahren kann nur durch Ablehnen von bestimmten Anfragen Vorteile gegenüber dem Referenz-Entscheidungsverfahren generieren. Voraussetzung ist somit eine entsprechende Nachfrage nach den angebotenen Diensten eines Softwareagenten und somit nach dessen Mitgliedschaft in Multiagenten-Organisationen. Steht diese Nachfrage nicht in ausreichendem Maße zur Verfügung, kann im Allgemeinen kein Vorteil gegenüber anderen Ansätzen erzielt werden. Abhängig von der individuellen Situation an angebotenen Diensten wirkt sich auch ein bestimmtes Verhältnis an nachfragenden Multiagenten-Organisationen positiv auf das Ergebnis des vorgestellten Verfahrens aus: Ist die überwiegende Zahl der Anfragen auf niederwertige Dienste oder Dienstgüteklassen ausgerichtet, jedoch auch eine ausreichend hohe Zahl an höherwertigen Anfragen vorhanden, erzielt das Verfahren deutliche Steigerungen gegenüber dem Referenz-Entscheidungsverfahren. Die voran genannten Voraussetzungen haben sich in der simulativen Evaluation als wesentlich für eine Vorteilhaftigkeit der Anwendung des entwickelten Verfahrens herausgestellt. Wenden Softwareagenten das entwickelte Verfahren für Beitrittsentscheidungen zu Multiagenten-Organisationen in Domänen an, die diese Voraussetzungen erfüllen, ist eine Steigerung der erwirtschafteten Kompensation gegenüber dem Referenz-Entscheidungsverfahren wahrscheinlich. Falls die Nachfrage kleiner als erwartet ausfällt, erzielte das Verfahren häufig die gleiche Kompensation wie das Referenz-Entscheidungsverfahren und erwirtschaftete nur in einzelnen Simulationsdurchläufen deutlich weniger, so dass selbst bei a-priori unbekannten oder unsicheren Parametern eine Anwendung des entwickelten Verfahrens möglich ist.
Linking farm economics and hydrology: Model integration for watershed-level irrigation management applied to Chile
(2010) Arnold, Thorsten; Berger, Thomas
As largest user of fresh water, the agricultural sector must resolve conflict of objectives ranging from economic goals of farmers to societal and environmental targets. Research must deliver tools to manage these objectives simultaneously. Single disciplines have resolved numerous problems with disciplinary solutions. However, problems emerging from interactions and feedbacks between disciplines can only be assessed with interdisciplinary tools and managed by institutions that coordinate across departments. Such complex problems are becoming an epochal task for Natural Resource Management (NRM). A number of modeling tools exist for irrigation management at watershed level that quantify biophysical processes and water quality. Simultaneously, agricultural economics developed production planning methods for allocating water resources optimally. However, integrated planning support tools are not available that take into account both domains and their interactions. Within a larger research project, it was the objective of this Ph.D. project to develop and test methods that integrate two complex modelling softwares for irrigation management. The distributed runoff model WaSiM-ETH quantifies water flows and evapotranspiration. The dynamic land use model MP-MAS is a multi-agent system in which farmers use economic reasoning to derive cropping decisions under given environmental conditions. Furthermore, the MP-MAS software contains the bucket model EDIC, which parameterizes the distribution of water from rivers to individual farmers through the canal system. Finally, the MP-MAS software was extended with a crop yield model with complementary irrigation. Model integration is understood as service provided within a research context. This context is defined by the study region, the project setting and by the strategic decisions within the research project - such as the choice of partner institutions and disciplines. Within the Maule River watershed in Chile (Linares Province, Region VII), the project ?Integrating Governance and Modeling? assessed the use of water in agriculture. Empirical research questions as well as modeling software were also part of this research context. Integration requires the conceptual, the technical and the procedural level. Conceptual integration describes processes and interactions between farmers, the canal system as distribution infrastructure and the natural system. It also describes how farmers plan and produce within this environment. Here, scale-dependent processes like irrigation efficiency or access to water by individuals were scrutinized. Technical integration is the implementation of the conceptual system into source code, e.g. by adapting legacy software, and by creating a software layer for hierarchical coupling of all software components. Procedural integration is the calibration, analysis, error eradication and validation of these models within the research context. Calibration and analysis of integrated model components is a step-by-step procedure. For all relevant processes and interactions, empirical data was first compiled and cross-evaluated. Then, standalone model components were calibrated so that interactions were parameterized as boundary conditions that are consistent across all disciplines. Empirical data pinpointed conceptual inconsistencies in the description of interactions, and standalone models were improved together with project partners. Ultimately, model components were coupled in such ways that interactions can be analyzed dynamically at minimum model- and software complexity. The calibration process along transdisciplinary cause-effect-chains resulted in the improvement of disciplinary models and model results. For example, the relevance of access to water beyond legalized water rights became apparent when empirical data and models were combined. Also, the calibration of the EDIC model required consistent use of data from all four disciplines and improved the calibration of the MP-MAS model. For the WaSiM-ETH model, an irrigation module was developed that is consistent across scales and reflects the needs of extension workers. Finally, model integration and coupling is discussed as research process. The process of calibrating a model with four components is not only a technical challenge for modellers and data management, but also a procedural challenge with regards to cooperation beyond disciplinary institutions and cultures. The structure of the integration process should be robust against errors and equally facilitate knowledge transfer between disciplines, iterative calibration across disciplines. Success factors are suggested to reduce transaction cost during the integration process.
Modeling crop yield and farmer adaptation to rainfall variability : the case of Southern Ethiopia
(2016) Bocher, Temesgen Fitamo; Berger, Thomas
Improving the livelihood of poor households in developing countries by increasing agricultural productivity and production becomes the priority agenda for development actors. However, variability in rainfall has confronted success in achieving this goal. There is pressing interest in analyzing the effects of rainfall variability on household welfare and identifying policy interventions to mitigate its adverse effects. Ethiopian economy primarily depends on rain-fed agriculture. Agriculture is the backbone of the country’s economy; it contributes the lions share of GDP, employment, export earnings, and livelihood. Fluctuations in rainfall distribution and intensity have severely affected the economy in general and the livelihood of smallholder households in particular; the agricultural sector is more prone to changes in climatic condition, which increases the risk of poverty and hunger for poor farm households. Few studies have attempted to analyze the direct effects of rainfall variability on crop yield and its indirect effect on household welfare. Therefore, this thesis aimed at filling the knowledge gap on the impacts of rainfall variability on crop yield and welfare. Moreover, the study explores the role of adaptation strategies in mimicking the negative effects of rainfall variability accounting for household performance decision under resource constraint for Ethiopian farmers. The study employed Mathematical Programming Based Multi-Agent System (MP-MAS) computer simulation techniques to analyze the effects of rainfall variability on crop yield, household welfare and the role of adaptation strategies in mitigating the adverse effects of rainfall variability. Prior to application to the study, the MP-MAS simulation model is parametrized, calibrated, and validated using data from the Ethiopian Rural Household Survey (ERHS), primary data collected from the research area and thirty year rainfall time series data obtained from meteorological stations located near to the study area. To address the mentioned research question a wide range of rainfall and adaptation strategy scenarios were designed. The agent - based model enables us to incorporate different bioeconomic systems in the decision-making process by smallholder farmers, which is otherwise difficult under a real world situation where farm households face inseparable decision-making process. Moreover, the model accounts for the heterogeneity in resource endowment, investment, production, consumption, agro-ecology, input constraints, and demographic distribution among households. Livestock, consumption, crop growth and irrigation water distribution models were combined in this study. The household food consumption decision is estimated by using three stages advanced consumption module and crop water requirement and irrigation water distribution modeled using inbuilt FAO CropWat and EDIC modules, and finally an empirical analysis was done by using STATA version 12. The simulation result suggested that: (i) Both current and future rainfall variability would have negative effects on crop yield and household welfare. (ii) The yield of cereals crops and vegetables are negatively affected by rainfall variability: some perennial crops such as enset gains yield under rainfall variability. (iii) Household welfare deteriorated with rainfall variability; resource poor households are severely affected by rainfall variability. (iv) Adaptation strategies such as non-farm activities, irrigation, and soil and water conservation activities mitigate the negative effects of rainfall variability. (v) Improving the financial or non-farm constraints alone leads to increased income inequality. Therefore, the recommended solution to reduce adverse effects of rainfall variability includes: (i) Implementing integrated policy interventions than a single strategy. (ii) Improving access to credit and access to non-farm activities. (iii) Designing a pro-poor intervention (such as improving the asset base of the poor households). (iv) Improving access and use of improved agricultural technologies, and (v) Increasing access and use of irrigation to enhance agricultural productivity.
Qualitatives, räumliches Schließen zur Kollisionserkennung und Kollisionsvermeidung autonomer BDI-Agenten
(2011) Kirn, Stefan; Schüle, Michael
Die Trends und Veränderungen in der Logistik führen zu einem dezentralen Ansatz der Steuerungssysteme, um die Komplexität logistischer Systeme zu reduzieren. Softwareagenten, insbesondere BDI-Agenten (Belief-Desire-Intention), als Gegenstand dieser Arbeit, bieten aufgrund ihrer Eigenschaften geeignete Konzepte diesen Ansatz umzusetzen. Im räumlichen Kontext ist das Wissen der Agenten über ihre Umwelt häufig unsicher. Dieser Beitrag adressiert das Problem der autonomen, kollisionsfreien Bewegung von mehreren, interagierenden Agenten auf Basis von unsicherem Wissen im Kontext der Transportlogistik. Zu diesem Zweck bietet die Perspektive des qualitativ räumlichen Schließens geeignete Konzepte. Der Ansatz wird durch eine Multiagentensimulation in einem transportlogistischen Szenario, im Speziellen mit verschiedenen organisationstheoretischen Konzepten bezüglich des Verhaltens der Agenten ausgewertet.
Simulation of the sustainability of farming systems in Northern Thailand
(2008) Potchanasin, Chakrit; Zeddies, Jürgen
Introduction Due to an increase in environmental problems and resource degradation, economic development should be pursued with consideration of environmental functions and the supply and quality of natural resources. Monitoring and assessment of whether the development approaches a sustainable path are required to provide information for policy development. This becomes increasingly important ? especially for marginal areas where the environment and natural resources are sensitive. The study area is located in the mountainous area of Northern Thailand with abundant natural resources and a healthy ecological environment. However, population growth, land limitation, and external factors ? such as market forces ? are inducing change and pressure on resource utilization. The resources are intensively used and farming systems are changing to more commercial practices. Therefore, the region?s long term sustainability needs investigation. Objectives This study aims at assessing the sustainability of the farming systems in the study area under the sustainability concept, farming systems approach and Multi-Agent Systems (MAS) approach. The first objective of this study is to describe the characteristics of the farming systems in the study area. The second objective is to develop and use a MAS model to evaluate sustainability of the study area. The last objective is to use the model to present sustainability of farming systems under different scenarios based on changes of significant factors and policy intervention. In addition, the ability of the systems to cope with and recover themselves from these changes is examined. Methodology The sustainability of the farming systems in the study area was assessed through defined indicators representing three conditions: the economic, social and environmental condition. The indicators were defined based on the framework of indicator determination to serve the objectives and methodology of this study. The selected indicators for this study are: household income, net farm income, household capital, household saving, food security, top-soil erosion and fallow period. For these indicators the following sustainability classes were defined: Sustained (S), Conditional sustained (C), and Non-sustained (N) class. Evaluation of sustainability was carried out at two levels: the household and the village level. At the household level the sustainability situation was evaluated based on the individual farm household performance corresponding to each indicator. The sustainability at village level was assessed through the Sustainability index (SI) when single indicators are considered and the Performance index (PI) in which a group of indicators is regarded. The dynamics of the sustainability situation at household and village level were extrapolated over 15 years (2003 ? 2017) in order to examine the sustainability of the study area?s farming systems. The MAS model was developed and named CatchScapeFS. The model structure relies on descriptions of the farming systems in the study area. The MAS approach was applied in order to capture the complexity and extrapolate the long-term sustainability situation in the study area. The model composes of two components: a biophysical and a socioeconomic component. The biophysical component is based on the CatchScape3 model. It consists of biophysical models: a hydrological model, a crop model, a water balance model and a soil erosion model, which are embedded in the landscape model of the study area (represented in spatial grid cells as plots of one rai or 0.16 ha). The socioeconomic component is composed of farm household agents and other social elements. The farm household samples were classified based on the similarity of characteristics and behaviour into the market, subsistence, and partnership oriented group. The Monte Carlo technique was applied to generate farm agents out of the existing farm household samples. The CatchScapeFS model was designed according to the object-oriented modelling approach. The CORMAS platform was selected as a capable tool to facilitate modelling and simulation. During a simulation time step covering 10 days, activities in six principal phases including activities in eight phases of farm agent household activities are executed. The model was validated and tested for its stability. Validation was conducted by social validation and statistic data comparison validation. The results of the model validation and stability test showed the reliability of using the model to serve the study objectives. Main results Sustainability of study area at the household level The results show unsustainability over time in the study area. The number of households in the Sustained class (S) decreases whereas the number in the Non-sustained (N) and Conditional sustained class (C) tend to increase. For the economic condition, unsustained aspects occurred because of rising private household expenditure and decreasing capital products on the farm. For the social condition, the results show an increase of the households? rice deficit and rice acquisition in the long run which enhances the area?s unsustainability. For the environmental condition, erosion and shortening fallow aspects induce the area?s unsustainability. The area?s erosion is severe and increases over time. For the fallow aspect, the average fallow period is shortening because of intensive land use in order to produce for consumption ? which potentially induces land degradation in the long run. Sustainability of the study area at village level Similar to the results at household level, the findings show that farming systems in the study area are not sustainable. Unsustainability was observed by a declining Performance index (PI) and declining Sustainability indexes (SIs) of all indicators in the long term. By considering PI values with the trends, the area?s sustainability in economic condition is better than the social and especially environmental condition. This can be explained by relative high SI values for the economic indicators compared to the SIs of the social and environmental indicators. By considering all SIs and their dynamic trend, sustainability issues can be ranked to determine the sustainability issues which need to be improved. Food security is the most unsustained issue followed by the issues of household saving, household capital, top-soil erosion, household income, fallow period, and net farm income respectively. Scenario analysis The scenarios were the implementation of a policy to improve sustainability and occurrence of unexpected events through changes of biophysical and economic factors. The scenario of the sustainability improving policy is defined as introduction of a high yield variety of upland rice and maize including introduction of mango to the households who currently only produce annual crops. Unexpected events due to the change of biophysical factors were simulated with a drought and rain increasing scenario. A decreasing crop price scenario represented an unexpected event due to the change of an economic factor. Implementation of proposed sustainability improvement policy The results show that the sustainability in the study area is obviously improved; represented by an increase of the PI value with a positive trend over time. In addition, the SIs of many indicators increase in this scenario, except the SI of household saving, which was rather constant. The PI of economic indicators improves with a higher number of households in the sustainable class when considering the household income, net farm income and household capital indicators. For the social condition, PI and SI values of food security increase because of a reduced rice deficit. For the environmental condition, the PI value of the environmental indicators increases because of a reduction of soil erosion and a longer fallow periods. It can be concluded that this scenario provides a policy option which potentially leads to an improvement of the sustainability situation in the study area. Drought scenario The results show that the study area was still unsustainable similar to the baseline scenario. However, the results show a slightly better PI during drought with a higher value and a slower decrease over time. These are the effects of the trade-offs between the indicators. The top-soil erosion indicator (influenced by decreasing rain) becomes better. This positive effect compensates for the negative effects regarding household savings, food security and fallow period indicators ? which all declined. In addition, the simulation results presented the adaptation and reaction of farm agents to drought. Drought is perceived and causes a delay in planting to avoid damage. This induced a variation of the planted area. However, the variation becomes lower because of adaptation as the farm households learn from their experiences. During drought, an increase in the rice and maize deficiency occurred. The average amount of borrowed rice increased over time and the rice acquisition of the farm agents is performed by borrowing from the village rice bank and neighbours In addition, the farm agents acquire maize by collecting wild vegetables to feed their animals. Furthermore, the results indicate the ability of the farm households to cope with and to recover to some extent from a drought. Rain increasing scenario In this scenario, the study area was still unsustainable, similar to the baseline. However, for this scenario, the top-soil erosion is worse because of the increasing rainfall. The PI of economic indicators slightly increased in the first year with increasing rain because of the rising income from livestock production. However, this was caused by random effects influencing the model?s initial stage. For the social condition, there are only small random changes compared to the baseline scenario. For the environmental condition, the PI and SIs of environmental indicators become worse due to an increase of top-soil erosion. Price decreasing scenario The results show that the area?s sustainability is worse compared to the baseline. A reduction of the crop price directly affects household income and cash ? which consequently generates a cash deficit problem. However, due to the area characteristics and household behaviour, there is no effect on resource use because prices do not influence the farm agents? decision making. The PI of this scenario declines faster than in the baseline. This was affected by the decrease of the SIs of the economic indicators which decreased during the periods of the price fall. The households are confronted with a decline in cash which results in a deficiency of cash. Cash acquisition of the households is performed by selling livestock and borrowing from the village fund and neighbours. For the social and environmental condition, there are only small changes due to random effects. Policy recommendations Based on the study results, policies to improve sustainability of the study area farming systems are recommended. Firstly, to improve the area?s sustainability, the introduction of high yield variety of upland rice and maize with conservation practices as well as the introduction of mango to the farm households who currently produce only annual crops is recommended. Secondly, diverting research efforts to develop cash crop alternatives is required in order to improve household cash income. Thirdly, the promotion and support for raising livestock and off-farm activities, such as weaving and the development of tourism, should be performed in order to increase household cash income. Fourthly, awareness raising measures for stakeholders concerning environmental and resource protection have to be executed and achieved. For this, the CatchScapeFS model can be used as a tool to promote a common view between stakeholders. Fifthly, the introduction of birth control in this area is also necessary. Simultaneously, an understanding of households? regarding the effects of population growth should be created in order to obtain the villagers? cooperation without cultural conflicts. Recommendations for further research Guidelines for further studies and applications are recommended. Firstly, development of the model to be more realistic could be undertaken by representing more details of the systems, for example, introducing a nutrient soil dynamic model. However, this should be based on the considered research question (s) and should consider both the marginal benefits and marginal costs of development. Secondly, application of the CatchScapeFS model to other study areas would need to consider the compatibility of the model components and structure of the characteristics in the new study area. In addition, if applied to new areas the indicators to represent sustainability of the study area should be revised. Thirdly, applications following this study framework can be extended to different sustainability approaches ? such as sustainable rural livelihood or sustainable land management. However, the compatibility and relationship of the indicators with the study framework should be considered. Fourthly, a framework through application of object-oriented modelling is recommended as an alternative for further studies to investigate the consequences of policy interventions. However, resource requirements for any research application should be taken into account. Fifthly, the CatchScapeFS model can be used as a tool to test and monitor the effects of potential policies which can be implemented into Bor Krai village. Also, the model can be used as a tool to promote a common view of the overall village systems as well as to support collective decision making managed by stakeholders of the systems. Recommendations for newcomers to MAS application research Suggestions from the present study for newcomers have been proposed. The first recommendation to deal with the MAS application research is that newcomers have to learn the computer programs and programming. Learning programming with advice of programming experts at the beginning period and attention of newcomers to apply the code in different circumstances are highly recommended. Secondly, development of an integrated model in multidisciplinary research requires learning the academic knowledge from other disciplines. Therefore, determining the study objectives within the possible extent, introducing assumptions to simplify the additional disciplines, and consulting specialists to learn the required knowledge within a short time frame are suggested. Lastly, the development of integrated model requires a huge amount of data. Therefore, in the case which required data cannot be obtained, introducing assumptions based on theory and literature is recommended.
Verhaltensmodell für Softwareagenten im Public Goods Game
(2011) Kirn, Stefan; Müller, Marcus; Stern, Guillaume; Jacob, Ansger
Gegenstand der vorliegenden Arbeit ist das Verhaltensmodell von Softwareagenten in einem Public Goods Game. Agenten im Sinne der Arbeit besitzen jeweils eigene, individuelle Ziele und müssen sich im Hinblick auf ein übergeordnetes Gesamtziel im Multiagentensystem koordinieren. Dabei hängen die individuell und kollektiv erzielbaren Ergebnisse von der Wahl der Verhaltensmodelle der Agenten ab. Die Wahl eines rein eigennützigen Verhaltens kann zu Nutzeneinbußen führen; die Wahl eines selbstlosen Verhaltens kann die individuell erzielbaren Ergebnisse eines Agenten massiv beeinträchtigen, falls andere Agenten im System eigennützig spielen. Die Auswirkungen verschiedener, aus der sozio-ökonomischen Theorie entlehnter Verhaltensmodelle in unterschiedlich gestalteten Agenten-Gesellschaften wird mittels einer Simulation untersucht. Die vorliegende Arbeit soll somit einen Beitrag liefern, um auf Basis deskriptiver sozio-ökonomischer Verhaltensmodelle Aussagen über das Verhalten von Softwareagenten (präskriptive Modelle) zu erlauben. Die Erkenntnisse helfen Entwicklern von Multiagentensystemen bei der Implementierung eines problemadäquaten Agentenverhaltens.