This thesis consists of a summary and four papers. The first two papers address political economy and indus-trial organization aspects of agricultural policy, and the last two international aspects of environmental policy. Paper [I] explains Common Agricultural Policy (CAP) subsidies to farmers by the influence of farmer interest-groups with an EU-wide membership. The analysis is based on panel-data for fifteen commodities over the period 1986-2003. Because the CAP is set as an overall EU policy, effective lobbying presents a collective ac-tion problem to the farmers in the EU as a whole. Indicators of lobbying, which are based on this perception, are found to explain part of the variation in agricultural support. In Paper [II], the Bresnahan-Lau framework is used to analyze whether policy reforms, i.e. the two-price sys-tem (an input quota, 1986-1991) and a general deregulation of dairy policy (1991-1994) had any market power effects on the Swedish butter market. The results show that the null hypothesis of no market power cannot be rejected, for any of the specific policy reforms, at any reasonable significance level. Paper [III] concerns the welfare consequences of environmental policy cooperation. It is assumed that coun-tries finance their public expenditures by using distortionary taxes, and that they differ with respect to compe-tition in the labor market. It is shown how the welfare effect of an increase in the expenditures on abatement depends on changes in the environmental damage, employment and work hours. The welfare effect is also related to the strategic interaction among the countries in the prereform equilibrium. In Paper [IV] environmental policy in an economic federation, where each national government faces a mixed tax problem, is addressed. It is assumed that the federal government sets emission targets, which are imple-mented at the national level. It is also assumed that the economic federation is decentralized. The results high-light a strategic role of income and commodity taxation, i.e. each country uses its policy instruments, at least in part, to influence the emission target.

The contemporary Internet ecosystem today has gone through series of evolutionary changes during the last forty or fifty years. Though it was designed as a network with fixed nodes, it has scaled well enough with the development of new technologies both in fixed and wireless networks. Initially, the communication model of the Internet was based on the telephone network (and can be considered as the 1st Generation Internet). Later, its transition as a client-server model made it a network where communication systems exchange data over dedicated links. This 2nd Generation Internet, over the years, has been challenged by many problems and issues such as network congestion, path failure, DOS attacks, mobility issues for wireless networks, etc. The Internet users always look for some information, irrespectively where it is located or stored. This approach is the basic building block for a network architecture where information is considered as the premier entity. Such networks, in general, are termed as Information Centric Network (ICN), where information takes centric position superseding the node centric approach like in the current Internet. The problems faced by the current Internet architecture, mentioned above, can be handled with a unifying approach by putting the information at the centre of the network architecture. On a global scale, this network architecture design is termed as the Future Information Centric Internet. Similarly, Mobile Internet usage has increased overwhelmingly in the last decade. There has been an estimated 1.2 billion mobile broad-band subscriptions for 2.4 billion Internet users in 2011. Because of the increased spectrum efficiency and ubiquitous availability of cellular connectivity, the seamless mobility and connectivity is now considered as daily life commodity. However, in the case of the Internet, IP based mobility solutions cannot catch up in performance with the fast evolution of cellular networks. Therefore, one of the primary goals for the Future Internet is the design of mobility management schemes that overcome the issues in wireless networks such as handover and location management, multihoming, security, etc. In this thesis, we have proposed a mobility management solution in wireless networks in the context of ICN in general and in the context of Network of Information (NetInf) in particular. NetInf is ICN-based Future Internet architecture. We propose a NetInf Mobile Node (NetInf MN) architecture which is backward compatible with the current Internet architecture as well. This cross architecture design for mobility support works closely with Central Control Unit (CCU) (network entity) for improved performance in case of handover management in wireless networks. The Virtual Node Layer (VNL) algorithm explains how different modules of NetInf MN and CCU units work together. The game theoretical and Reinforcement Learning (CODIPAS-RL) scheme based mathematical model shows how handover management and data relaying in the wireless networks can increase the network coverage through cooperative diversity. Simulation results show that the proposed model achieves both Nash and Stackelberg equilibria where as the selected CODIPAS-RL scheme reaches global optimum. Finally, as a use case example of NetInf architecture, we propose the NetInf Email service that does not require dedicated servers or dedicated port unlike the current email service. The use of asymmetric keys as user's ID is the unique feature proposed for this service. The NetInf email service architecture framework presented, explains how different architectural components work together. We discuss different challenges and requirements related to this service. The prototype developed for the Network of Information will be used for the implementation of this service

Made available in DSpace on 2015-05-15T11:45:59Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 715500 bytes, checksum: d95f1a0101cba7f4f31b21e2b0da1bb3 (MD5) Previous issue date: 2011-07-22 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The present work has the distributed control v applied to the linear wave's equation. We seek to reach two objective, one of the kind Controllability and another the not system state distance to a state y2 (x; t) predefined. This is an problem of multicriteria optimization, and to solves him, introduce the notion Stackelberg's Optimal Control (classical in economy), in which we divide v into two, tell v1 and v2, and each one will act in the respective part from the Boundary 1;2 with a hierarchy between the same. This way, we take over that v1 is the control leader and v1 will be the follower. To leave of this terminogy, we use the idea of the hierarchical control, that is, admit that given a right v1, optimize the second goal concerning v2 and find a relation such that v2 = F (v1). So, the first goal became function of v1, belonging to the kind approximate controlability that will be proved through a density criterion and a Holmgren's uniqueness theorem. Finally, proved for controlability close, from unicidade of the solution, find Optimality system for the control leader. / O presente trabalho tem o controle distribuído v aplicado á fronteira da Equação da Onda Linear. Buscamos atingir dois objetivos: um do tipo controlabilidade, e outro o não distanciamento do estado do sistema a um estado y2 (x; t) predefinido. Esse é um problema de otimização multicritério, e para solucioná-lo, introduzimos a noção de controle ótimo de Stackelberg (clássico em economia), no qual dividimos v em dois, digamos v1 e v2; e cada um atuará na respectiva parte da fronteira -1; -2, com uma hierarquia entre os mesmos. Assim, assumimos que v1 é o controle líder e v2 será o seguidor. A partir dessa terminologia, usamos a ideia do controle hierárquico, isto é, admitimos que dado um certo v1, otimizamos o segundo objetivo com respeito a v2 e encontramos uma relação tal que v2 = F (v1). Então, o primeiro objetivo tornou-se função de v1; sendo do tipo controlabilidade aproximada que será provado através de um critério de densidade e do teorema de unicidade de Holmgren. Por último, provada a controlabilidade aproximada e a partir da unicidade da solução, encontramos o sistema de otimalidade para o controle líder.

Made available in DSpace on 2015-05-15T11:46:05Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 674722 bytes, checksum: eb17d5816a0fce98d1def5be593711f1 (MD5) Previous issue date: 2011-09-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / We have as main issue in this work the Hierarchical Control, which consists in a leader-followers system. We studied in special the heat equation approximate controllability under Stackelberg-Nash’s strategy, which is directed in controlling every system from local controls choices with the minimum possible costs. / Temos como principal tema neste trabalho o Controle Hierárquico, que consiste em um sistema de líder e seguidores. Estudamos em especial a controlabilidade aproximada da equação do Calor sob a estratégia de Stackelberg-Nash, estratégia esta direcionada em controlar todo sistema a partir de escolhas de controles locais com o mínimo de custos possíveis.

No description available.

Conventional medical imaging technologies for cancer diagnosis utilize fixed geometric configuration of the source and the detector to image the target. In this dissertation, we hypothesize that dynamic utilization of source and detector geometry will lead to better performance of medical imaging devices. Interrogating a target in a three dimensional space requires cooperation and coordination between the source and detector positions. The goal of this dissertation is to develop a dynamic imaging method, which will improve the tumor characterization performance, and provide a control scheme appropriate for the dynamic interrogation. This dissertation proposes a bimodal dynamic imaging (BDI) method for improving tumor characterization and a hybrid hierarchical statistical control scheme for the autonomous control of the sources and detectors. The tactile imaging sensor has high specificity but low sensitivity in tumor characterization. The spectral sensor has high sensitivity but low specificity. The BDI system integrates the tactile sensing and the spectral sensing modalities with the capability of dynamic positioning of the source and detector to determine the mechanical and spectral properties of a tumor. The tactile sensing can estimate the mechanical properties of the tumor, such as size, depth, and elastic modulus, while the spectral sensing can determine the absorption coefficient of the tumor through diffuse optical imaging. These properties help us characterize the tumor, and differentiate cancerous tissues from healthy tissues. We designed and experimentally evaluated the BDI system for estimating the size, depth, elastic modulus, and absorption coefficient of embedded inclusions. The system performance in characterizing mechanical properties was then compared to that of the tactile imaging sensor. The proposed BDI method was experimentally validated using fabricated bimodal phantom. The experimental results showed that the tactile imaging system (TIS) estimated the tumor phantom size with 7.23% error; BDI measured the size with 0.8% error. The TIS depth estimation error was 41.83%; BDI reduced the depth measurement error to 20.00%. The TIS elastic modulus estimation error was 96.80%; the BDI method showed 74.79% error. Additionally, BDI estimated the absorption coefficient with 14%-25% estimation error. For further improvement the system performance, this bimodal imaging system is implemented on a dual-arm robot, Baxter, where the laser source and the tactile imaging sensors were mounted on the end-effectors. Each arm of Baxter robot has seven Degree-of- Freedom. This provides more flexibility in terms of interrogating the target compared to the fixed geometric configuration. We devised a hybrid statistical controller for maneuvering the source and the detector of the system. In this control architecture, a high-level supervisory controller was used for the functions at a higher level for coordinating two arms. At lower level, a full-state feedback statistical controller was used to facilitate the minimum position variation. A linear model for the dual-arm Baxter robot was derived for testing the proposed architecture. We performed the simulations of hybrid hierarchical statistical controller on the Baxter model for trajectory tracking. The simulation studies demonstrated accurate sequential task execution for the bimodal dynamic imaging system using a hybrid hierarchical statistical control. / Electrical and Computer Engineering

<p dir="ltr">Amidst the rising popularity of digital marketplaces, addressing issues such as non-<br>payment/non-delivery crimes, centralization risks, hacking threats, and the complexity of<br>ownership transfers has become imperative. Many existing studies exploring blockchain<br>technology in digital marketplaces and asset management merely touch upon various application scenarios without establishing a unified platform that ensures trustworthiness and<br>efficiency across the product life cycle. In this thesis, we focus on designing a reliable and efficient e-commerce model to trade various assets. To enhance customer engagement through<br>consensus, we utilize the XGBoost algorithm to identify loyal nodes from the platform entities pool. Alongside appointed nodes, these loyal nodes actively participate in the consensus<br>process. The consensus algorithm guarantees that all involved nodes reach an agreement on<br>the blockchain’s current state. We introduce a novel consensus mechanism named Modified-<br>Practical Byzantine Fault Tolerance (M-PBFT), derived from the Practical Byzantine Fault<br>Tolerance (PBFT) protocol to minimize communication overhead and improve overall efficiency. The modifications primarily target the leader election process and the communication<br>protocols between leader and follower nodes within the PBFT consensus framework.</p><p dir="ltr"><br>In the domain of tangible assets, our primary objective is to elevate trust among various<br>stakeholders and bolster the reputation of sellers. As a result, we aim to validate secondhand<br>products and their descriptions provided by the sellers before the secondhand products are<br>exchanged. This validation process also holds various entities accountable for their actions.<br>We employ validators based on their location and qualifications to validate the products’<br>descriptions and generate validation certificates for the products, which are then securely<br>recorded on the blockchain. To incentivize the participation of validator nodes and up-<br>hold honest validation of product quality, we introduce an incentive mechanism leveraging<br>Stackelberg game theory.</p><p dir="ltr"><br>On the other hand, for optimizing intangible assets management, we employ Non-Fungible<br>Tokens (NFT) technology to tokenize these assets. This approach enhances traceability of<br>ownership, transactions, and historical data, while also automating processes like dividend<br>distributions, royalty payments, and ownership transfers through smart contracts. Initially,<br>sellers mint NFTs and utilize the InterPlanetary File System (IPFS) to store the files related<br>to NFTs, NFT metadata, or both since IPFS provides resilience and decentralized storage solutions to our network. The data stored in IPFS is encrypted for security purposes.<br>Further, to aid sellers in pricing their NFTs efficiently, we employ the Stackelberg mechanism. Furthermore, to achieve finer access control in NFTs containing sensitive data and<br>increase sellers’ profits, we propose a Popularity-based Adaptive NFT Management Scheme<br>(PANMS) utilizing Reinforcement Learning (RL). To facilitate prompt and effective asset<br>sales, we design a smart contract-powered auction mechanism.</p><p dir="ltr"><br>Also, to enhance data recording and event response efficiency, we introduce a weighted<br>L-H index algorithm and transaction prioritization features in the network. The weighted<br>L-H index algorithm determines efficient nodes to broadcast transactions. Transaction prior-<br>itization prioritizes certain transactions such as payments, verdicts during conflicts between<br>sellers and validators, and validation reports to improve the efficiency of the platform. Simulation experiments are conducted to demonstrate the accuracy and efficiency of our proposed<br>schemes.<br></p>

L’argument central de notre thèse est qu’une structure internationale unipolaire non hégémonique favorise la sécurité collective. Après avoir montré que telle est la structure actuelle et avoir justifié notre positionnement théorique néolibéral, nous avons eu recours au modèle d’interaction du « leader-suiveur de Stackelberg », pour démontrer qu’une coopération conflictuelle entre États rationnels est possible, ce qui leur permet de surmonter leur dilemme de l’action collective. Une coopération possible en raison de l’existence d’un intérêt mutuel et d’un leader favorisant la coopération entre ces États, ainsi que de conditions leur permettant de mettre en place une ‘stratégie de la réciprocité’. Ils forment alors ce qu’on appelle le « groupe de Stackelberg ». Le suiveur de la périphérie, ou ‘défecteur’ doit, pour sa part, non seulement s’ajuster à l’intérêt mutuel ainsi défini, mais aussi coopérer et négocier avec le groupe, et ce, sous la pression de sanctions, voire d’un usage ultime de la force si besoin est. Après l’éventuel succès de ces négociations, un équilibre de Stackelberg favorisé par le leader, soit la puissance unipolaire et non hégémonique, est alors atteint et la coopération permet, alors, à chacun de retirer un bénéfice de cet intérêt mutuel. Dans notre cas, le groupe de Stackelberg est constitué des membres du G5 + 1, soit les cinq membres permanents du Conseil de Sécurité de l’ONU et de l’Allemagne, agissant sous le leadership américain; l’Iran est un suiveur de la périphérie, soupçonné de défection, et l’intérêt mutuel est celui de la lutte contre la prolifération des ADM. Notre évaluation empirique montre que les conditions de la réciprocité des membres de ce groupe sont réunies et que celles de l’Iran sont en cours de négociation. / The main argument of our thesis is that a unipolar and non hegemonic structure of the international system furthers collective security. After having shown that the present international structure is as such and having justified our neoliberal theoretical approach, we have adopted the interaction model of the Stackelberg leadership model to demonstrate that a conflicting cooperation between rational States, that are respectful of the international order, is possible, which allows them to overcome their collective action dilemma. This cooperation depends on the existence of shared interests, on the ability of the leader to foster cooperation among them, and on structural conditions as well, which enable the setting up of “a reciprocity strategy”. They, thus, form what we call as a “Stackelberg’s group”. With regard to the periphery follower, or defector, he should adjust to the mutual interest of the group, as defined by this latter, as well as cooperate and negotiate with it, under the pressure of sanctions or the use of force if necessary. In the event of a successful negotiation, a Stackelberg equilibrium, furthered by the leader of the group, that is the unipolar and non hegemonic power, is then reached where cooperation between the members of the group, i.e. the States, allows them to get their share, that is a benefit from their mutual interest. In our case study, the Stackelberg’s group includes the five permanent members of the U.N Security Council plus Germany, all acting under the US leadership. Iran is a periphery follower suspected of defection, and the mutual interest is the international security against WMD proliferation. Our empirical assessment shows that the respective conditions, which enable a reciprocity strategy within the Stackelberg’s group, are then met by its members, whereas those of Iran are still under negotiations.

This dissertation focuses on selected issues in regard to the mathematical modeling of electricity markets. In a first step the interrelations of electric power market modeling are highlighted a crossroad between operations research, applied economics, and engineering. In a second step the development of a large-scale continental European economic engineering model named ELMOD is described and the model is applied to the issue of wind integration. It is concluded that enabling the integration of low-carbon technologies appears feasible for wind energy. In a third step algorithmic work is carried out regarding a game theoretic model. Two approaches in order to solve a discretely-constrained mathematical program with equilibrium constraints using disjunctive constraints are presented. The first one reformulates the problem as a mixed-integer linear program and the second one applies the Benders decomposition technique. Selected numerical results are reported.

L’argument central de notre thèse est qu’une structure internationale unipolaire non hégémonique favorise la sécurité collective. Après avoir montré que telle est la structure actuelle et avoir justifié notre positionnement théorique néolibéral, nous avons eu recours au modèle d’interaction du « leader-suiveur de Stackelberg », pour démontrer qu’une coopération conflictuelle entre États rationnels est possible, ce qui leur permet de surmonter leur dilemme de l’action collective. Une coopération possible en raison de l’existence d’un intérêt mutuel et d’un leader favorisant la coopération entre ces États, ainsi que de conditions leur permettant de mettre en place une ‘stratégie de la réciprocité’. Ils forment alors ce qu’on appelle le « groupe de Stackelberg ». Le suiveur de la périphérie, ou ‘défecteur’ doit, pour sa part, non seulement s’ajuster à l’intérêt mutuel ainsi défini, mais aussi coopérer et négocier avec le groupe, et ce, sous la pression de sanctions, voire d’un usage ultime de la force si besoin est. Après l’éventuel succès de ces négociations, un équilibre de Stackelberg favorisé par le leader, soit la puissance unipolaire et non hégémonique, est alors atteint et la coopération permet, alors, à chacun de retirer un bénéfice de cet intérêt mutuel. Dans notre cas, le groupe de Stackelberg est constitué des membres du G5 + 1, soit les cinq membres permanents du Conseil de Sécurité de l’ONU et de l’Allemagne, agissant sous le leadership américain; l’Iran est un suiveur de la périphérie, soupçonné de défection, et l’intérêt mutuel est celui de la lutte contre la prolifération des ADM. Notre évaluation empirique montre que les conditions de la réciprocité des membres de ce groupe sont réunies et que celles de l’Iran sont en cours de négociation. / The main argument of our thesis is that a unipolar and non hegemonic structure of the international system furthers collective security. After having shown that the present international structure is as such and having justified our neoliberal theoretical approach, we have adopted the interaction model of the Stackelberg leadership model to demonstrate that a conflicting cooperation between rational States, that are respectful of the international order, is possible, which allows them to overcome their collective action dilemma. This cooperation depends on the existence of shared interests, on the ability of the leader to foster cooperation among them, and on structural conditions as well, which enable the setting up of “a reciprocity strategy”. They, thus, form what we call as a “Stackelberg’s group”. With regard to the periphery follower, or defector, he should adjust to the mutual interest of the group, as defined by this latter, as well as cooperate and negotiate with it, under the pressure of sanctions or the use of force if necessary. In the event of a successful negotiation, a Stackelberg equilibrium, furthered by the leader of the group, that is the unipolar and non hegemonic power, is then reached where cooperation between the members of the group, i.e. the States, allows them to get their share, that is a benefit from their mutual interest. In our case study, the Stackelberg’s group includes the five permanent members of the U.N Security Council plus Germany, all acting under the US leadership. Iran is a periphery follower suspected of defection, and the mutual interest is the international security against WMD proliferation. Our empirical assessment shows that the respective conditions, which enable a reciprocity strategy within the Stackelberg’s group, are then met by its members, whereas those of Iran are still under negotiations.