京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第18255号 / 工博第3847号 / 新制||工||1590(附属図書館) / 31113 / 京都大学大学院工学研究科都市社会工学専攻 / (主査)教授 小林 潔司, 准教授 宇野 伸宏, 准教授 松島 格也 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

Web 2.0時代強調由使用者貢獻內容，並藉由使用者的互動來創造群體智慧的價值。社會性書籤網站統合散佈在各處的網路資訊（尤其是由使用者所產生的部落格文章），承接內容的生產及閱讀，是網路內容價值鏈樞紐；另一方面，從媒體的角度來看，書籤網站可視為是web 2.0下的公民新聞守門人（引路人），以公民取代專業編輯，提供了一個完全不一樣的公民媒體運作方式。本研究針對社會性書籤網站中的內容評價推薦機制，探討其群體智慧運作情形：參考動物群體行為的運作原則，加上文獻的整理及實際案例的觀察，建構出社會性書籤網站推薦機制的模擬運作架構；並透過代理人模擬方法，來找出影響網站群體智慧運作的原則，及相關屬性設定對運作結果的影響。研究結果發現，社會性書籤網站的運作成效，可以分為篩選效果及文章更新效率，兩者之間具有魚與熊掌不可兼得的特性，並可藉由不同的閱讀策略安排來調整。基於web 2.0的特性，使用者同時扮演服務的生產者與消費者。因此，使用者閱讀文章時的閱讀策略安排，可視為是群體智慧運作中的工作分配策略。而群體智慧的運作原則中，正回饋效應可以提升篩選效果，判斷獨立性可以提升文章的更新效率，抑制與負回饋則可以使系統較為穩定。本研究除了為web 2.0網站的群體智慧經營提供具體的參考方針，多重代理人模擬的方法也可做為往後web 2.0相關研究及網站經營時的工具。 / The core spirit for web 2.0 is the contribution of users, and the creation of value through the interaction between users. Social book marking sites integrate all kind of contents on the Internet (especially those generated by users), and play the role of pivot between content production and consumption. From the aspect of media, social bookmarking site can be regarded as news gatekeeper (or gateway) in the web 2.0 era. This study focuses on the rating and recommendation mechanism of social bookmarking sites, trying to find out the effects of collective wisdom with regard to different operations. The principle of collective animal behavior and the existing operations of some social bookmarking sites are first surveyed. Then, an operational model of social bookmarking sites and its recommendation mechanism is built and used for subsequent simulation. / The research findings show that the performance of social bookmarking sites has a tradeoff between sifting effect and efficiency, and that the performance can be controlled through a job allocation strategy. The operation of 「positive feedback」in collective wisdom can lead to sifting effect, 「integrity and variability」 leads to efficiency, and 「negative feedback」, 「inhibition」 lead to system stability. This research is believed to provide some managerial guidelines for web 2.0 sites operation.

The surveillance of geographic borders and critical infrastructures using limited sensor capability has always been a challenging task in many homeland security applications. While geographic borders may be very long and may go through isolated areas, critical assets may be large and numerous and may be located in highly populated areas. As a result, it is virtually impossible to secure each and every mile of border around the country, and each and every critical infrastructure inside the country. Most often, a compromise must be made between the percentage of border or critical asset covered by surveillance systems and the induced cost. Although threats to homeland security can be conceived to take place in many forms, those regarding illegal penetration of the air, land, and maritime domains under the cover of day-to-day activities have been identified to be of particular interest. For instance, the proliferation of drug smuggling, illegal immigration, international organized crime, resource exploitation, and more recently, modern piracy, require the strengthening of land border and maritime awareness and increasingly complex and challenging national security environments. The complexity and challenges associated to the above mission and to the protection of the homeland may explain why a methodology enabling the design and optimization of distributed detection systems architectures, able to provide accurate scanning of the air, land, and maritime domains, in a specific geographic and climatic environment, is a capital concern for the defense and protection community. This thesis proposes a methodology aimed at addressing the aforementioned gaps and challenges. The methodology particularly reformulates the problem in clear terms so as to facilitate the subsequent modeling and simulation of potential operational scenarios. The needs and challenges involved in the proposed study are investigated and a detailed description of a multidisciplinary strategy for the design and optimization of detection architectures in terms of detection performance and cost is provided. This implies the creation of a framework for the modeling and simulation of notional scenarios, as well as the development of improved methods for accurate optimization of detection architectures. More precisely, the present thesis describes a new approach to determining detection architectures able to provide effective coverage of a given geographical environment at a minimum cost, by optimizing the appropriate number, types, and locations of surveillance and detection systems. The objective of the optimization is twofold. First, given the topography of the terrain under study, several promising locations are determined for each sensor system based on the percentage of terrain it is covering. Second, architectures of sensor systems able to effectively cover large percentages of the terrain at minimal costs are determined by optimizing the number, types and locations of each detection system in the architecture. To do so, a modified Genetic Algorithm and a modified Particle Swarm Optimization are investigated and their ability to provide consistent results is compared. Ultimately, the modified Particle Swarm Optimization algorithm is used to obtain a Pareto frontier of detection architectures able to satisfy varying customer preferences on coverage performance and related cost.

The thesis investigates how Agent-Based Modeling and Simulation (ABMS) and Queueing Theory (QT) techniques help manage mass gathering (MG) crowds. The techniques are applied to Hajj MG, which is one of the most complex annual MG, with a focus on its challenging Tawaf ritual. The objective is to develop a Tawaf Decision Support System (DSS) to better understand Tawaf crowd dynamics and discover decisions that lead to superior performance. TawafSIM is an ABMS model in the DSS, which simulates macro-level Tawaf crowd dynamics through micro-level pilgrim modeling to explore the impact of crowd characteristics, facility layout, and management preferences on emergent crowd behaviours with respect to throughput, satisfaction, health, and safety. Whereas, TawafQT is a QT model in the DSS to explore the impact of pilgrim arrival rate and Tawaf throughput on expected arrival, departure, and waiting times along with average queue length in the Tawaf waiting area. The thesis provides several contributions, including the following. First, it is the only Tawaf research to use a hybrid ABMS and QT approach. Second, TawafSIM is a comprehensive Tawaf simulator. It incorporates features for pilgrim characteristics, facility design, and management preferences. It calculates eight metrics for Tawaf performance, which includes one for throughput, three for satisfaction, one for health, and three for safety. It is the only Tawaf simulator to estimate satisfaction and spread of infectious disease. It conducts 42 simulation experiments in 12 categories. It generates observations for emergent, tipping point, expected, and counter intuitive behaviours. It recommends a default scenario as the best decision along with a small subset of alternative scenarios, which provide above average Tawaf performance. It generates a Tawaf Crowd Management Guide to better understand Tawaf crowd dynamics and how to pursue above average Tawaf performance under different conditions. Third, TawafQT is the only study of the Tawaf waiting area. It uses an accurate queueing model with finite source, single service, and PH type distribution, which is not only applicable to the Tawaf and other Hajj related queueing systems but also to any queueing system, which has finite population and single service characteristics.

The thesis investigates how Agent-Based Modeling and Simulation (ABMS) and Queueing Theory (QT) techniques help manage mass gathering (MG) crowds. The techniques are applied to Hajj MG, which is one of the most complex annual MG, with a focus on its challenging Tawaf ritual. The objective is to develop a Tawaf Decision Support System (DSS) to better understand Tawaf crowd dynamics and discover decisions that lead to superior performance. TawafSIM is an ABMS model in the DSS, which simulates macro-level Tawaf crowd dynamics through micro-level pilgrim modeling to explore the impact of crowd characteristics, facility layout, and management preferences on emergent crowd behaviours with respect to throughput, satisfaction, health, and safety. Whereas, TawafQT is a QT model in the DSS to explore the impact of pilgrim arrival rate and Tawaf throughput on expected arrival, departure, and waiting times along with average queue length in the Tawaf waiting area. The thesis provides several contributions, including the following. First, it is the only Tawaf research to use a hybrid ABMS and QT approach. Second, TawafSIM is a comprehensive Tawaf simulator. It incorporates features for pilgrim characteristics, facility design, and management preferences. It calculates eight metrics for Tawaf performance, which includes one for throughput, three for satisfaction, one for health, and three for safety. It is the only Tawaf simulator to estimate satisfaction and spread of infectious disease. It conducts 42 simulation experiments in 12 categories. It generates observations for emergent, tipping point, expected, and counter intuitive behaviours. It recommends a default scenario as the best decision along with a small subset of alternative scenarios, which provide above average Tawaf performance. It generates a Tawaf Crowd Management Guide to better understand Tawaf crowd dynamics and how to pursue above average Tawaf performance under different conditions. Third, TawafQT is the only study of the Tawaf waiting area. It uses an accurate queueing model with finite source, single service, and PH type distribution, which is not only applicable to the Tawaf and other Hajj related queueing systems but also to any queueing system, which has finite population and single service characteristics.

Nos travaux de thèse portent sur la modélisation et la simulation à base d'agents de systèmes complexes, appliquées au phénomène de propagation de la Schistosomose. Plus particulièrement, nous nous sommes intéressés aux aspects spatiaux et sociaux de la propagation de cette maladie, en utilisant une approche de couplage de modèles à base d'agents. En effet, nous avons initialement étudié la modélisation mathématique de la Schistosomose et la complexité du phénomène de sa propagation. Ce qui nous a permis d'identifier deux dynamiques épidémiologiques (dynamiques spatiale et sociale) sous-jacentes à la propagation de la Schistosomose pour lesquelles, les modèles mathématiques présentent des limites. Cette problématique nous a poussés à étudier isolément ces deux dynamiques et à proposer un modèle multi-agents pour chacune d'elles. Ces deux modèles à base d'agents, représentant deux dynamiques complémentaires d'un même système, ont été implémentés selon des formalismes et des plateformes différentes : un modèle dans GAMA, une plateforme de simulation à base d'agents ; et un autre dans JASON, une plateforme de programmation d'agents BDI (Belief, Desire, Intention). Le modèle GAMA implémente l'aspect comportemental (pour la dynamique spatiale) qui se penche sur la réactivité des individus face à l'environnement physique et le suivi de l'infection. Le modèle JASON implémente l'aspect décisionnel (pour la dynamique sociale) qui introduit la dimension cognitive et mentale des individus en assurant leur capacité de décision et de sélection qui sont déterminées par leur environnement social, culturel, économique, etc. Pour assurer la composition des deux modèles, nous avons proposé une solution de couplage (par Co-simulations) des deux plateformes GAMA et JASON. Nous avons finalement expérimenté le modèle avec un cas de dynamique de propagation de la maladie à Niamey (au Niger) pour lequel les données étaient accessibles. / Our thesis work focuses on agent-based modeling and simulation of complex systems, applied to the spread of schistosomiasis. Specially, we were interested in the spatial and social aspects of the spread of the disease, using an agent-based coupling approach of models.Indeed, we initially studied the mathematical modeling of schistosomiasis and the complexity of its propagation, which allowed us to identify two epidemiological dynamics (spatial and social dynamics) underlying the spread of schistosomiasis for which mathematical models have limits. This problematic led us to study separately these two dynamics and propose an agent-based model for each. These two agent-based models, representing two complementary dynamics of a system, were implemented according different formalisms and different platforms: one model on GAMA (an agent-based simulation platform); and another on JASON (a programming platform of BDI agents). The GAMA model implements the behavioral aspect (for the spatial dynamic) that focuses on individuals reactivity with regards to the physical environment, and the monitoring of the infection. The JASON model implements the decisional aspect (for the social dynamic) that introduces the cognitive and mental dimension of individuals, ensuring their decision and selection capacities which are determined by their social, cultural and economic environment. To ensure the composition of the two models, we proposed an agent-based coupling solution (co-simulation) of the two platforms (GAMA and JASON). We finally experienced the model with a case of dynamic spread of the disease in Niamey (Niger) for which data were available.

Made available in DSpace on 2016-10-13T14:10:04Z (GMT). No. of bitstreams: 1 Leonardo Yuji Tamura.pdf: 2018327 bytes, checksum: dca70d285f6272ea72951fe189bab096 (MD5) Previous issue date: 2016-03-22 / The aim of this work is to deepen the understanding of the process of adaptation of firms in the international environment. For such it relied on studies that faced the firm as a complex adaptive system and utilized the Stuart Kauffman s NK model. The NK model was originally conceived to study biological phenomena but has been applied by scholars in strategy and organizational studies since 1997. To enable the use of the NK model for the study of multinational firms, the model was extended to embrace specific international business concepts such as the gaining of competitive advantage in different countries from the adaptation of the firm s internal characteristics to the local environment. The chosen methodology is based on the paradigm of agent-based modeling and simulation. Accordingly, the firms were modeled as autonomous agents that search for the optimization of their competitive advantage by the means of the adaptation process. This approach allowed the study the emergent properties of the system from the agents interaction and behavior. The results of the simulation showed that gaining competitive advantage from the firm s attributes in different countries enabled the emergence of new viable organizational forms. It was also noted that one organizational form that does not provides optimal competitive advantage in a particular country may still be viable in a global context. Another result was the emergence of the complexity catastrophe, which is the degradation of the competitive advantage resulted from the addition of conflicting constraints. Such conflicting constraints are a result of the simultaneous optimization of the competitive advantage in many countries in many different ways due to the possibility of local adaptation. / O objetivo deste trabalho é aprofundar o entendimento sobre o processo de adaptação de empresas no ambiente internacional. Para isto foram utilizados estudos que encararam a empresa como um sistema adaptativo complexo e utilizaram o modelo NK de Stuart Kauffman. O modelo NK foi originalmente concebido para o estudo de fenômenos biológicos, mas vem sendo aplicado por acadêmicos em trabalhos de estratégia e organizações desde 1997. Para que fosse possível utilizar o modelo NK para o estudo de empresas multinacionais, o modelo foi estendido para abarcar conceitos específicos de negócios internacionais como, por exemplo, a obtenção de vantagem competitiva em diferentes países a partir da adaptação de caraterísticas internas da empresa ao ambiente local. A metodologia utilizada foi baseada no paradigma da modelagem e simulação baseado em agentes. Com base neste paradigma as empresas foram modeladas como agentes autônomos que, por meio de um processo de adaptação buscam otimizar sua vantagem competitiva. Esta abordagem permite estudar propriedades emergentes do sistema a partir da interação e do comportamento dos agentes. Os resultados das simulações mostraram que a obtenção de vantagem competitiva a partir dos atributos organizacionais da empresa em diversos países possibilita o surgimento de novas formas organizacionais viáveis. Também se observou que uma forma organizacional que não propicia vantagem competitiva ótima em um país específico, ainda pode ser viável num contexto global. Outro resultado obtido foi a emergência da catástrofe da complexidade, que é a degradação da vantagem competitiva em decorrência da adição de restrições conflitantes. Tais restrições conflitantes são resultado da necessidade de otimizar simultaneamente a vantagem competitiva em diversos países de diversas formas diferentes devido à possibilidade de adaptação local.

在複雜動態競爭市場中，生產者的價格競爭行為一直是一個研究的重點，相較於生產者動態價格競爭，零售商的價格競爭行為鮮少被探討，因此本研究針對零售商價格競爭行為進行研究。針對零售商之間的價格競爭行為，除了考量零售商與對手零售商的價格互動，不可忽略的是上游供應商的競爭互動與下游消費者的學習行為在市場中與零售商端互動下錯綜複雜的動態影響，緣此，本研究以零售商端的角度，想了解供應商競爭與消費者學習行為對零售商競爭的影響，再以單一零售商角度，分析各情況下所應對的價格調整策略。 本研究將零售商、供應商及消費者互動形成之競爭市場視為一個複雜適應性系統（Complex Adaptive System ，簡稱CAS），應用代理人基塑模與模擬（Agent-based Modeling and Simulation，簡稱ABMS）方式建構考量供應商競爭與消費者學習行為之零售商價格競爭模式，將演化賽局理論應用於價格競爭中，探討不同的消費者學習及供應商價格競爭行為如何動態影響零售商價格競爭型態，以及不同價格調整策略之績效表現。 研究結果發現一，市場中消費者呈現不同的學習行為，對零售商競爭將造成不同的衝擊。「貨比三家無學習」型消費者將造成零售商端低價競爭，使其平均價格最低及獲利最低。「自我式學習」型消費者將造成零售商高價合作，使其平均價格最高及獲利最高。「群體式學習」型消費者同樣使零售商端偏向高價合作，且其平均價格及獲利相當接近自我式學習市場，雖然兩種學習行為具有近似的平均價格與獲利，「群體式學習」卻會導致零售商價格競爭之型態轉為劇烈，包括獲利領先轉換方式由漸進轉為瀑布，領先方式從勢均力敵轉為大幅領先，領先互換的頻率由低轉為高。另外，消費者購買決策之理性程度對零售商端競爭形態有影響，不論在何種供應商行為下，高理性購買決策在群體式學習下將導致零售商端價格競爭較激烈，在自我式學習下卻導致零售商端競爭行為較緩和。 研究發現二，市場中供應商的價格競爭行為會對零售商端的價格、獲利與競爭型態造成衝擊。供應商呈現價格競爭行為下，在「貨比三家無學習」之消費者行為市場中，將減緩零售商價格競爭，使零售商端之平均價格及獲利提高。在「自我」與「群體式」學習消費者市場中，將增強零售商價格競爭強度，使零售商端之平均價格及獲利降低。 研究發現三，不同的競爭市場中，零售商之最佳價格調整策略也將不同。基本上在供應商無競爭行為下，無論消費者呈現何種行為，零售商採取開放式價格調整策略具有明顯優勢。在供應商呈現競爭行為下，開放式價格調整策略在「無學習」及「群體式學習高理性程度」行為市場仍為優勝策略，在「自我式學習」及「群體式學習低理性程度」下，保守型價格調整策略則表現較佳。 在實務意涵上，若零售商可使消費者行為偏向自我或群體式學習，並穩定供應商價格競爭下，整體而言零售商端競爭可獲得最高的獲利，若當此刻競爭零售商採取保守型價格策略，而本身採取開放式價格調整策略，則獲利最大。然而面臨群體式學習消費者，由於競爭強度的增加，需留意市場動態，須隨時靈活調整本身價格策略，避免因價格策略的僵化，而成為虧損之零售商。 / The pricing competitive model traditionally assumes that consumers will buy from the firm selling the homogeneous product at the lowest price, thus discarding any possibility of learning behavior on the demand side. But if, as in real competition, consumers learn adaptively and competition is a dynamic process, then some attention should be paid to consumers' behavior. In a multiple supplier – multiple retailer supply chain, multiple price competitive forces interact to influence firm price decisions. These forces include: (1) the supplier level competition each supplier faces from others producing the same product, (2) the retailer level competition among the retailers selling the same set of goods, and (3) the vertical interaction competition between the retailer and supplier. We are interest in these questions: How does the consumer learning behavior affect the retailer pricing competitive model? How does the competition of supplier affect the retailer pricing competitive model? What is the optimal adaptive pricing strategy for retailer performance in such competitive market including retailers, suppliers and consumers. Therefore, this research study a version of the pricing competitive (Bertrand) model in which consumer exhibit dynamic adaptive learning behavior when deciding from what retailers they will buy. And we consider to join the supplier competitive pricing behavior into the retailer pricing competitive model and formulate their interaction as evolutional game and to analyze the competition of supplier effect and its impact on the pricing competition of retailers. This research uses a complex adaptive system perspective to construct a retailer pricing competitive model which considers both competitive supplier and learning consumer behavior. Using agent-based modeling and simulation (ABMS) to construct the competitive market include retailers, suppliers and consumers, and use the fuzzy logic, genetic algorithms to model the pricing decision and learning behavior of retailers and suppliers, and use reinforcement learning and swarm algorithms to model consumers’ learning behavior. The simulation results demonstrate that: The retailer level obtains the highest profit when the consumer behavior following reinforcement learning. When the consumer behavior displays swarm learning, the retailer level also obtains high profit near the highest profit. However swarm learning increases the competitive intensity on the retailer level. The competitive supplier increases the competitive intensity and decrease profit on the retailer level when the consumer behavior displays reinforcement learning and swarm learning. The performance of retailer following a closed adaptive pricing strategy (high exploitation low exploration) exceeds that of retailer following an open adaptive pricing strategy (low exploitation high exploration) when the consumer behavior displays reinforcement learning and supplier display competitive behavior. However when the consumer behavior displays swarm learning and supplier display competitive behavior, the performance of retailer following an open adaptive pricing strategy exceeds that of retailer following a closed adaptive pricing strategy. The proposed pricing competitive model with adaptive learning of consumer behavior and competition of supplier can help retailers to analyze pricing strategy and further discovery and design the more optimal pricing strategy.