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Compositional Multi-objective Parameter TuningHusak, Oleksandr 07 July 2020 (has links)
Multi-objective decision-making is critical for everyday tasks and engineering problems. Finding the perfect trade-off to maximize all the solution's criteria requires a considerable amount of experience or the availability of a significant number of resources. This makes these decisions difficult to achieve for expensive problems such as engineering. Most of the time, to solve such expensive problems, we are limited by time, resources, and available expertise. Therefore, it is desirable to simplify or approximate the problem when possible before solving it. The state-of-the-art approach for simplification is model-based or surrogate-based optimization. These approaches use approximation models of the real problem, which are cheaper to evaluate. These models, in essence, are simplified hypotheses of cause-effect relationships, and they replace high estimates with cheap approximations. In this thesis, we investigate surrogate models as wrappers for the real problem and apply \gls{moea} to find Pareto optimal decisions.
The core idea of surrogate models is the combination and stacking of several models that each describe an independent objective. When combined, these independent models describe the multi-objective space and optimize this space as a single surrogate hypothesis - the surrogate compositional model. The combination of multiple models gives the potential to approximate more complicated problems and stacking of valid surrogate hypotheses speeds-up convergence. Consequently, a better result is obtained at lower costs.
We combine several possible surrogate variants and use those that pass validation. After recombination of valid single objective surrogates to a multi-objective surrogate hypothesis, several instances of \gls{moea}s provide several Pareto front approximations. The modular structure of implementation allows us to avoid a static sampling plan and use self-adaptable models in a customizable portfolio. In numerous case studies, our methodology finds comparable solutions to standard NSGA2 using considerably fewer evaluations. We recommend the present approach for parameter tuning of expensive black-box functions.:1 Introduction
1.1 Motivation
1.2 Objectives
1.3 Research questions
1.4 Results overview
2 Background
2.1 Parameter tuning
2.2 Multi-objective optimization
2.2.1 Metrics for multi-objective solution
2.2.2 Solving methods
2.3 Surrogate optimization
2.3.1 Domain-specific problem
2.3.2 Initial sampling set
2.4 Discussion
3 Related Work
3.1 Comparison criteria
3.2 Platforms and frameworks
3.3 Model-based multi-objective algorithms
3.4 Scope of work
4 Compositional Surrogate
4.1 Combinations of surrogate models
4.1.1 Compositional Surrogate Model [RQ1]
4.1.2 Surrogate model portfolio [RQ2]
4.2 Sampling plan [RQ3]
4.2.1 Surrogate Validation
4.3 Discussion
5 Implementation
5.1 Compositional surrogate
5.2 Optimization orchestrator
6 Evaluation
6.1 Experimental setup
6.1.1 Optimization problems
6.1.2 Optimization search
6.1.3 Surrogate portfolio
6.1.4 Benchmark baseline
6.2 Benchmark 1: Portfolio with compositional surrogates. Dynamic sampling plan
6.3 Benchmark 2: Inner parameters
6.3.1 TutorM parameters
6.3.2 Sampling plan size
6.4 Benchmark 3: Scalability of surrogate models
6.5 Discussion of results
7 Conclusion
8 Future Work
A Appendix
A.1 Benchmark results on ZDT DTLZ, WFG problems
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Risk–constrained stochastic economic dispatch and demand response with maximal renewable penetration under renewable obligationHlalele, Thabo Gregory January 2020 (has links)
In the recent years there has been a great deal of attention on the optimal demand and supply side
strategy. The increase in renewable energy sources and the expansion in demand response programmes
has shown the need for a robust power system. These changes in power system require the control of
the uncertain generation and load at the same time. Therefore, it is important to provide an optimal
scheduling strategy that can meet an adequate energy mix under demand response without affecting
the system reliability and economic performance. This thesis addresses the following four aspects to
these changes.
First, a renewable obligation model is proposed to maintain an adequate energy mix in the economic
dispatch model while minimising the operational costs of the allocated spinning reserves. This method
considers a minimum renewable penetration that must be achieved daily in the energy mix. If the
renewable quota is not achieved, the generation companies are penalised by the system operator. The
uncertainty of renewable energy sources are modelled using the probability density functions and
these functions are used for scheduling output power from these generators. The overall problem is
formulated as a security constrained economic dispatch problem.
Second, a combined economic and demand response optimisation model under a renewable obligation
is presented. Real data from a large-scale demand response programme are used in the model. The
model finds an optimal power dispatch strategy which takes advantage of demand response to minimise
generation cost and maximise renewable penetration. The optimisation model is applied to a South
African large-scale demand response programme in which the system operator can directly control
the participation of the electrical water heaters at a substation level. Actual load profile before and
after demand reduction are used to assist the system operator in making optimal decisions on whether
a substation should participate in the demand response programme. The application of these real
demand response data avoids traditional approaches which assume arbitrary controllability of flexible
loads.
Third, a stochastic multi-objective economic dispatch model is presented under a renewable obligation.
This approach minimises the total operating costs of generators and spinning reserves under renewable
obligation while maximising renewable penetration. The intermittency nature of the renewable energy
sources is modelled using dynamic scenarios and the proposed model shows the effectiveness of the
renewable obligation policy framework. Due to the computational complexity of all possible scenarios,
a scenario reduction method is applied to reduce the number of scenarios and solve the model. A Pareto
optimal solution is presented for a renewable obligation and further decision making is conducted to
assess the trade-offs associated with the Pareto front.
Four, a combined risk constrained stochastic economic dispatch and demand response model is presented
under renewable obligation. An incentive based optimal power dispatch strategy is implemented
to minimise generation costs and maximise renewable penetration. In addition, a risk-constrained
approach is used to control the financial risks of the generation company under demand response
programme. The coordination strategy for the generation companies to dispatch power using thermal
generators and renewable energy sources while maintaining an adequate spinning reserve is presented.
The proposed model is robust and can achieve significant demand reduction while increasing renewable
penetration and decreasing the financial risks for generation companies. / Thesis (PhD (Electrical Engineering))--University of Pretoria, 2020. / Electrical, Electronic and Computer Engineering / PhD (Electrical Engineering) / Unrestricted
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Multi-objective day-ahead scheduling of microgrids using modified grey wolf optimizer algorithmJavidsharifi, M., Niknam, T., Aghaei, J., Mokryani, Geev, Papadopoulos, P. 10 August 2018 (has links)
Yes / Investigation of the environmental/economic optimal operation management of a microgrid (MG) as a case study for applying a novel modified multi-objective grey wolf optimizer (MMOGWO) algorithm is presented in this paper. MGs can be considered as a fundamental solution in order for distributed generators’ (DGs) management in future smart grids. In the multi-objective problems, since the objective functions are conflict, the best compromised solution should be extracted through an efficient approach. Accordingly, a proper method is applied for exploring the best compromised solution. Additionally, a novel distance-based method is proposed to control the size of the repository within an aimed limit which leads to a fast and precise convergence along with a well-distributed Pareto optimal front. The proposed method is implemented in a typical grid-connected MG with non-dispatchable units including renewable energy sources (RESs), along with a hybrid power source (micro-turbine, fuel-cell and battery) as dispatchable units, to accumulate excess energy or to equalize power mismatch, by optimal scheduling of DGs and the power exchange between the utility grid and storage system. The efficiency of the suggested algorithm in satisfying the load and optimizing the objective functions is validated through comparison with different methods, including PSO and the original GWO. / Supported in part by Royal Academy of Engineering Distinguished Visiting Fellowship under Grant DVF1617\6\45
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Multiple Objective Evolutionary Algorithms for Independent, Computationally Expensive ObjectivesRohling, Gregory Allen 19 November 2004 (has links)
This research augments current Multiple Objective Evolutionary Algorithms with methods that dramatically reduce the time required to evolve toward a region of interest in objective space.
Multiple Objective Evolutionary Algorithms (MOEAs) are superior to other optimization techniques when the search space is of high dimension and contains many local minima and maxima. Likewise, MOEAs are most interesting when applied to non-intuitive
complex systems. But, these systems are often computationally expensive to calculate. When these systems require independent computations to evaluate each objective, the computational expense grows with each additional objective. This method has developed methods that reduces the time required for evolution by reducing the number of objective evaluations, while still evolving solutions that are Pareto optimal. To date, all other Multiple Objective Evolutionary Algorithms (MOEAs) require the evaluation of all objectives before a fitness value can be assigned to an individual.
The original contributions of this thesis are:
1. Development of a hierarchical search space description that allows association of crossover and mutation settings with elements of the genotypic description.
2. Development of a method for parallel evaluation of individuals that removes the need for delays for synchronization.
3. Dynamical evolution of thresholds for objectives to allow partial evaluation of objectives for individuals.
4. Dynamic objective orderings to minimize the time required for unnecessary objective evaluations.
5. Application of MOEAs to the computationally
expensive flare pattern design domain.
6. Application of MOEAs to the optimization of fielded missile warning receiver algorithms.
7. Development of a new method of using MOEAs for
automatic design of pattern recognition systems.
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Automated estimation of time and cost for determining optimal machining plansVan Blarigan, Benjamin 30 July 2012 (has links)
The process of taking a solid model and producing a machined part requires the time and skillset of a range of professionals, and several hours of part review, process planning, and production. Much of this time is spent creating a methodical step-by-step process plan for creating the part from stock. The work presented here is part of a software package that performs automated process planning for a solid model. This software is capable of not only greatly decreasing the planning time for part production, but also give valuable feedback about the part to the designer, as a time and cost associated with manufacturing the part. In order to generate these parameters, we must simulate all aspects of creating the part. Presented here are models that replicate these aspects. For milling, an automatic tool selection method is presented. Given this tooling, another model uses specific information about the part to generate a tool path length. A machining simulation model calculates relevant parameters, and estimates a time for machining given the tool and tool path determined previously. This time value, along with the machining parameters, is used to estimate the wear to the tooling used in the process. Using the machining time and the tool wear a cost for the process can be determined. Other models capture the time of non-machining production times, and all times are combined with billing rates of machines and operators to present an overall cost for machining a feature on a part. If several such features are required to create the part, these models are applied to each feature, until a complete process plan has been created.
Further post processing of the process plan is required. Using a list of available machines, this work considers creating the part on all machines, or any combination of these machines. Candidates for creating the part on specific machines are generated and filtered based on time and cost to keep only the best candidates. These candidates can be returned to the user, who can evaluate, and choose, one candidate. Results are presented for several example parts. / text
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Μεθοδολογίες στην πολυ-αντικειμενική βελτιστοποίησηΑντωνέλου, Γεωργία 07 December 2010 (has links)
Σε αυτήν την εργασία, παρουσιάζουμε τις βασικότερες κλασικές προσεγγίσεις επίλυσης Πολυ-αντικειμενικών Προβλημάτων Βελτιστοποίησης(ΠΠΒ)καθώς και ένα από τα πιο δημοφιλή λογισμικά για επίλυση ΠΠΒ, το NIMBUS. Συγκεκριμένα, δίνουμε τον ορισμό ενός ΠΠΒ, το θεωρητικό υπόβαθρο -- για την καλύτερη κατανόηση
των μεθόδων που θα ακολουθήσουν - και τις διαφορές των ΠΠΒ με τα κλασσικά Μονο-αντικειμενικά προβλήματα Βελτιστοποίησης. Επιπλέον, παρουσιάζουμε τις τρεις κύριες κατηγορίες προσέγγισης των ΠΠΒ (μη-αλληλεπιδραστικές, αλληλεπιδραστικές, εξελικτικές) ο διαχωρισμός των οποίων γίνεται ανάλογα με την άμεση ή έμμεση
εμπλοκή του Λήπτη Απόφασης. Η μελέτη μας εστιάζεται κυρίως στην κατηγορία των μη-αλληλεπιδραστικών προσεγγίσεων, στην οποία ο ΛΑ εμπλέκεται έμμεσα.
Τέλος, ολοκληρώνουμε την μελέτη μας με την αναλυτική παρουσίαση της επίλυσης ενός ΠΠB με την χρήση του λογισμικού NIMBUS. / In this contribution, we study the classical approaches for solving Multi-objective Optimization Problems (MOOP) as well as one of the most popular software that solves MOOP, namely NIMBUS. More specifically, we present the definition and the theoretical background around MOOP and
we discuss the differences between MOOP and the classical single-objective optimization problems. We also present the three main categories of
approaches of solving MOOP (non-interactive, interactive, evolutionary) that are characterized by the way the Decision Maker participates in the solution.
We focus on the first category by analyzing each of the non-interactive approaches.
Finally, we conclude by presenting an analytic illustration of an example that solves a MOOP using the NIMBUS software.
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Joint Optimization of Quantization and Structured Sparsity for Compressed Deep Neural NetworksJanuary 2018 (has links)
abstract: Deep neural networks (DNN) have shown tremendous success in various cognitive tasks, such as image classification, speech recognition, etc. However, their usage on resource-constrained edge devices has been limited due to high computation and large memory requirement.
To overcome these challenges, recent works have extensively investigated model compression techniques such as element-wise sparsity, structured sparsity and quantization. While most of these works have applied these compression techniques in isolation, there have been very few studies on application of quantization and structured sparsity together on a DNN model.
This thesis co-optimizes structured sparsity and quantization constraints on DNN models during training. Specifically, it obtains optimal setting of 2-bit weight and 2-bit activation coupled with 4X structured compression by performing combined exploration of quantization and structured compression settings. The optimal DNN model achieves 50X weight memory reduction compared to floating-point uncompressed DNN. This memory saving is significant since applying only structured sparsity constraints achieves 2X memory savings and only quantization constraints achieves 16X memory savings. The algorithm has been validated on both high and low capacity DNNs and on wide-sparse and deep-sparse DNN models. Experiments demonstrated that deep-sparse DNN outperforms shallow-dense DNN with varying level of memory savings depending on DNN precision and sparsity levels. This work further proposed a Pareto-optimal approach to systematically extract optimal DNN models from a huge set of sparse and dense DNN models. The resulting 11 optimal designs were further evaluated by considering overall DNN memory which includes activation memory and weight memory. It was found that there is only a small change in the memory footprint of the optimal designs corresponding to the low sparsity DNNs. However, activation memory cannot be ignored for high sparsity DNNs. / Dissertation/Thesis / Masters Thesis Computer Engineering 2018
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Multiobjective optimization approaches in bilevel optimization / Les techniques d’optimisation multicritère en optimisation à deux niveauxPieume, Calice Olivier 10 January 2011 (has links)
Cette thèse aborde l'optimisation multicritère et l'optimisation à deux niveaux. L'investigation porte principalement sur les méthodes, les applications et les liens possibles entre les deux classes d'optimisation. Premièrement, nous développons une méthode de résolution des problèmes d'optimisation linéaire multicritère. Pour ce faire, nous introduisons une nouvelle caractérisation des faces efficaces et exploitons le résultat selon lequel l'ensemble des tableaux idéaux associés aux sommets extrêmes dégénérés est connexe. Ceci a permis de développer une approche de parcours de sommet extrême pour générer l'ensemble des solutions efficaces. Dans le même ordre d'idée, nous développons une méthode de résolution des problèmes linéaires à deux niveaux. L'approche est basée sur un résultat, que nous avons formalisé et démontré, qui stipule que la solution optimale du problème linéaire à deux niveaux est l'un des sommets extrêmes du domaine admissible. L'implémentation de l'approche a permis de démontrer qu'il existait dans la littérature des problèmes dont les solutions connues étaient fausses. Deuxièmement, en termes d'applications, nous construisons un modèle d'optimisation multicritère pouvant être exploité dans l'optique d'une planification optimale de la distribution de l'énergie électrique au Cameroun. Nous proposons aussi, à partir d'un modèle d'optimisation à deux niveaux, une technique dont la mise en œuvre par l'État pourrait permettre de protéger les industries locales de la concurrence des firmes internationales. Enfin, nous étudions l'interrelation entre l'optimisation multicritère et l'optimisation à deux niveaux. Tout d'abord, nous tirons des conditions de Pareto-optimalité des solutions du problème à deux niveaux. Ensuite, nous montrons qu'il est possible d'obtenir une solution optimale de certaines classes de problèmes d'optimisation à deux niveaux en résolvant deux problèmes particuliers d'optimisation multicritère. Puis, nous étudions le cas de problème à deux niveaux dans lequel chaque décideur possède plusieurs fonctions objectifs conflictuelles, en nous focalisant sur le cas linéaire. Après, nous construisons un problème artificiel d'optimisation linéaire multicritère dont l'ensemble des solutions efficaces est égal au domaine des solutions admissibles du problème du leader. Pour terminer, nous utilisons ce résultat pour proposer deux approches de résolution dépendant chacune des aspirations du leader / This thesis addresses two important classes of optimization : multiobjective optimization and bilevel optimization. The investigation concerns their solution methods, applications, and possible links between them. First of all, we develop a procedure for solving Multiple Objective Linear Programming Problems (MOLPP). The method is based on a new characterization of efficient faces. It exploits the connectedness property of the set of ideal tableaux associated to degenerated points in the case of degeneracy. We also develop an approach for solving Bilevel Linear Programming Problems (BLPP). It is based on the result that an optimal solution of the BLPP is reachable at an extreme point of the underlying region. Consequently, we develop a pivoting technique to find the global optimal solution on an expanded tableau that represents the data of the BLPP. The solutions obtained by our algorithm on some problems available in the literature show that these problems were until now wrongly solved. Some applications of these two areas of optimization problems are explored. An application of multicriteria optimization techniques for finding an optimal planning for the distribution of electrical energy in Cameroon is provided. Similary, a bilevel optimization model that could permit to protect any economic sector where local initiatives are threatened is proposed. Finally, the relationship between the two classes of optimization is investigated. We first look at the conditions that guarantee that the optimal solution of a given BPP is Pareto optimal for both upper and lower level objective functions. We then introduce a new relation that establishes a link between MOLPP and BLPP. Moreover, we show that, to solve a BPP, it is possible to solve two artificial M0PPs. In addition, we explore Bilevel Multiobjective Programming Problem (BMPP), a case of BPP where each decision maker (DM) has more than one objective function. Given a MPP, we show how to construct two artificial M0PPs such that any point that is efficient for both problems is also efficient for the BMPP. For the linear case specially, we introduce an artificial MOLPP such that its resolution can permit to generate the whole feasible set of the leader DM. Based on this result and depending on whether the leader can evaluate or not his preferences for his different objective functions, two approaches for obtaining efficient solutions are presented
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Non-Cooperative Games for Self-Interested Planning AgentsJordán Prunera, Jaume Magí 03 November 2017 (has links)
Multi-Agent Planning (MAP) is a topic of growing interest that deals with the problem of automated planning in domains where multiple agents plan and act together in a shared environment. In most cases, agents in MAP are cooperative (altruistic) and work together towards a collaborative solution. However, when rational self-interested agents are involved in a MAP task, the ultimate objective is to find a joint plan that accomplishes the agents' local tasks while satisfying their private interests.
Among the MAP scenarios that involve self-interested agents, non-cooperative MAP refers to problems where non-strictly competitive agents feature common and conflicting interests. In this setting, conflicts arise when self-interested agents put their plans together and the resulting combination renders some of the plans non-executable, which implies a utility loss for the affected agents. Each participant wishes to execute its plan as it was conceived, but congestion issues and conflicts among the actions of the different plans compel agents to find a coordinated stable solution.
Non-cooperative MAP tasks are tackled through non-cooperative games, which aim at finding a stable (equilibrium) joint plan that ensures the agents' plans are executable (by addressing planning conflicts) while accounting for their private interests as much as possible. Although this paradigm reflects many real-life problems, there is a lack of computational approaches to non-cooperative MAP in the literature.
This PhD thesis pursues the application of non-cooperative games to solve non-cooperative MAP tasks that feature rational self-interested agents. Each agent calculates a plan that attains its individual planning task, and subsequently, the participants try to execute their plans in a shared environment. We tackle non-cooperative MAP from a twofold perspective. On the one hand, we focus on agents' satisfaction by studying desirable properties of stable solutions, such as optimality and fairness. On the other hand, we look for a combination of MAP and game-theoretic techniques capable of efficiently computing stable joint plans while minimizing the computational complexity of this combined task. Additionally, we consider planning conflicts and congestion issues in the agents' utility functions, which results in a more realistic approach.
To the best of our knowledge, this PhD thesis opens up a new research line in non-cooperative MAP and establishes the basic principles to attain the problem of synthesizing stable joint plans for self-interested planning agents through the combination of game theory and automated planning. / La Planificación Multi-Agente (PMA) es un tema de creciente interés que trata el problema de la planificación automática en dominios donde múltiples agentes planifican y actúan en un entorno compartido. En la mayoría de casos, los agentes en PMA son cooperativos (altruistas) y trabajan juntos para obtener una solución colaborativa. Sin embargo, cuando los agentes involucrados en una tarea de PMA son racionales y auto-interesados, el objetivo último es obtener un plan conjunto que resuelva las tareas locales de los agentes y satisfaga sus intereses privados.
De entre los distintos escenarios de PMA que involucran agentes auto-interesados, la PMA no cooperativa se centra en problemas que presentan un conjunto de agentes no estrictamente competitivos con intereses comunes y conflictivos. En este contexto, pueden surgir conflictos cuando los agentes ponen en común sus planes y la combinación resultante provoca que algunos de estos planes no sean ejecutables, lo que implica una pérdida de utilidad para los agentes afectados. Cada participante desea ejecutar su plan tal como fue concebido, pero las congestiones y conflictos que pueden surgir entre las acciones de los diferentes planes fuerzan a los agentes a obtener una solución estable y coordinada.
Las tareas de PMA no cooperativa se abordan a través de juegos no cooperativos, cuyo objetivo es hallar un plan conjunto estable (equilibrio) que asegure que los planes de los agentes sean ejecutables (resolviendo los conflictos de planificación) al tiempo que los agentes satisfacen sus intereses privados en la medida de lo posible. Aunque este paradigma refleja muchos problemas de la vida real, existen pocos enfoques computacionales para PMA no cooperativa en la literatura.
Esta tesis doctoral estudia el uso de juegos no cooperativos para resolver tareas de PMA no cooperativa con agentes racionales auto-interesados. Cada agente calcula un plan para su tarea de planificación y posteriormente, los participantes intentan ejecutar sus planes en un entorno compartido. Abordamos la PMA no cooperativa desde una doble perspectiva. Por una parte, nos centramos en la satisfacción de los agentes estudiando las propiedades deseables de soluciones estables, tales como la optimalidad y la justicia. Por otra parte, buscamos una combinación de PMA y técnicas de teoría de juegos capaz de calcular planes conjuntos estables de forma eficiente al tiempo que se minimiza la complejidad computacional de esta tarea combinada. Además, consideramos los conflictos de planificación y congestiones en las funciones de utilidad de los agentes, lo que resulta en un enfoque más realista.
Bajo nuestro punto de vista, esta tesis doctoral abre una nueva línea de investigación en PMA no cooperativa y establece los principios básicos para resolver el problema de la generación de planes conjuntos estables para agentes de planificación auto-interesados mediante la combinación de teoría de juegos y planificación automática. / La Planificació Multi-Agent (PMA) és un tema de creixent interès que tracta el problema de la planificació automàtica en dominis on múltiples agents planifiquen i actuen en un entorn compartit. En la majoria de casos, els agents en PMA són cooperatius (altruistes) i treballen junts per obtenir una solució col·laborativa. No obstant això, quan els agents involucrats en una tasca de PMA són racionals i auto-interessats, l'objectiu últim és obtenir un pla conjunt que resolgui les tasques locals dels agents i satisfaci els seus interessos privats.
D'entre els diferents escenaris de PMA que involucren agents auto-interessats, la PMA no cooperativa se centra en problemes que presenten un conjunt d'agents no estrictament competitius amb interessos comuns i conflictius. En aquest context, poden sorgir conflictes quan els agents posen en comú els seus plans i la combinació resultant provoca que alguns d'aquests plans no siguin executables, el que implica una pèrdua d'utilitat per als agents afectats. Cada participant vol executar el seu pla tal com va ser concebut, però les congestions i conflictes que poden sorgir entre les accions dels diferents plans forcen els agents a obtenir una solució estable i coordinada.
Les tasques de PMA no cooperativa s'aborden a través de jocs no cooperatius, en els quals l'objectiu és trobar un pla conjunt estable (equilibri) que asseguri que els plans dels agents siguin executables (resolent els conflictes de planificació) alhora que els agents satisfan els seus interessos privats en la mesura del possible. Encara que aquest paradigma reflecteix molts problemes de la vida real, hi ha pocs enfocaments computacionals per PMA no cooperativa en la literatura.
Aquesta tesi doctoral estudia l'ús de jocs no cooperatius per resoldre tasques de PMA no cooperativa amb agents racionals auto-interessats. Cada agent calcula un pla per a la seva tasca de planificació i posteriorment, els participants intenten executar els seus plans en un entorn compartit. Abordem la PMA no cooperativa des d'una doble perspectiva. D'una banda, ens centrem en la satisfacció dels agents estudiant les propietats desitjables de solucions estables, com ara la optimalitat i la justícia. D'altra banda, busquem una combinació de PMA i tècniques de teoria de jocs capaç de calcular plans conjunts estables de forma eficient alhora que es minimitza la complexitat computacional d'aquesta tasca combinada. A més, considerem els conflictes de planificació i congestions en les funcions d'utilitat dels agents, el que resulta en un enfocament més realista.
Des del nostre punt de vista, aquesta tesi doctoral obre una nova línia d'investigació en PMA no cooperativa i estableix els principis bàsics per resoldre el problema de la generació de plans conjunts estables per a agents de planificació auto-interessats mitjançant la combinació de teoria de jocs i planificació automàtica. / Jordán Prunera, JM. (2017). Non-Cooperative Games for Self-Interested Planning Agents [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/90417
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運用土地稅配合土地規劃管制實施之研究蔡慧麗, CAI,HUI-LI Unknown Date (has links)
於理論上,自由市場透過「價格機能」之運作,將使資源之配置與使用達到最高效率
,然此市場之運作需有某些前提–完全競爭及無外溢效果等方能成立。但於現實社會
中上述假設前提並不存在,致使柏拉圖的最適境界(pareto optimal)無法達成,尤其
是具有異質性,不可移動性、不可增減性之土地,更易導致土地市場的地理區隔及非
完全競爭等現象;外部性及公共財不足之市場失靈(Market Failure)問題更是伏拾皆
是;再者和經濟部門為追求最大利潤,往往罔顧社會成本,導致不當的土地配置與使
用。故政府之適當干預確有其必要,而土地規劃與管制則係反應此種需要,以修正及
彌補土地市場之缺失,俾達土地之合理配置與使用。
然而,土地規劃管制之實施過程中,由於各宗土地使用類別與密度之差異,或變更使
用等,往往對地價造成上漲或下只之經濟效果,導致土地所有權人間之利得(windfa-
ll) 或損失(wipeout) 之不公平現象,實有待積極改善。處理此類公平性問題的方法
有許多,例如區段征收、市地重劃、發展權移轉(T.D.R) 及稅捐等方式,本研究乃選
擇我國土地政策之最高指導原則–平均地權之主要政策手段–土地稅–進行研究。此
外,如何運用土地稅來促進土地規劃與使用管制目標之達成,亦為本研究之範圍。
故本研究擬基於效率與公平之觀點,參考國外土地稅制針對我國土地稅之課稅時機、
課稅方式、稅基、稅率結構等予以檢討分析,俾能改進現行之地價稅、土地增值稅與
空地稅的課征,以達平均地權之地盡其利與地利共享之崇高目標。
全文計六章,分別為:
第一章 緒論
第二章 文獻回顧
第三章 土地規劃管制與其公平性之探討
第四章 土地稅促進土地規劃管制實施之分析
第五章 現行我國土地稅制之檢討與改進措施
第六章 結論與建議
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