Thèses sur le sujet « Logic Constraints »
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1
Rönchen, Philipp. « Constraints of Binary Simple Homogeneous Structures ». Thesis, Uppsala universitet, Algebra och geometri, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-361217.
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Das, Subrata Kumar. « Integrity constraints in deductive databases ». Thesis, Heriot-Watt University, 1990. http://hdl.handle.net/10399/875.
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Senkul, Karagoz Pinar. « Specification And Scheduling Of Workflows Under Resource Allocation Constraints ». Phd thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/739193/index.pdf.
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Workflow is a collection of tasks organized to accomplish some business process. It also
defines the order of task invocation or conditions under which task must be invoked,
task synchronization, and information flow. Before the execution of the workflow, a
correct execution schema, in other words, the schedule of the workflow, must be determined.
Workflow scheduling is finding an execution sequence of tasks that obeys the
business logic of workflow. Research on specification and scheduling of workflows has
concentrated on temporal and causality constraints, which specify existence and order
dependencies among tasks. However, another set of constraints that specify resource allocation
is also equally important. The resources in a workflow environment are agents
such as person, machine, software, etc. that execute the task. Execution of a task has a cost and this may vary depending on the resources allocated in order to execute that
task. Resource allocation constraints define restrictions on how to allocate resources,
and scheduling under resource allocation constraints provide proper resource allocation
to tasks. In this thesis, we present two approaches to specify and schedule workflows
under resource allocation constraints as well as temporal and causality constraints. In
the first approach, we present an architecture whose core and novel parts are a specifi-
cation language with the ability to express resources and resource allocation constraints
and a scheduler module that contains a constraint solver in order to find correct resource
assignments. In the second approach, we developed a new logical formalism,
called Concurrent Constraint Transaction Logic (CCTR) which integrates constraint
logic programming (CLP) and Concurrent Transaction Logic, and a logic-based work-
flow scheduler that is based on this new formalism. CCTR has the constructs to specify
resource allocation constraints as well as workflows and it provides semantics for these specifications so that validity of a schedule can be checked.
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Taboada, Sophie. « Multi-Agent Motion Planning with Signal Temporal Logic Constraints ». Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-292870.
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Motion planning algorithms allow us to define a sequence of configurations to guide robots from a starting point to an ending goal while considering the environment’s and the robot’s constraints. As all robots and circumstances are different, motion planning can be adapted to fit into the system’s specifications and the user’s preferences. Temporal Logic (TL) has been used to enable the implementation of more complex missions. In this work, we are interested in using TL to establish the affiliation between robots in a multi-robot system, as well as their affiliation with features in the workspace. More specifically, Signal Temporal Logic (STL) is used to guide motion planning into respecting certain preferences linked to the robot’s motion behavior. In fact, user’s preferences are translated into STL formulas, that need to be respected by the motion planning. To achieve this, RRT* sampling-based algorithm is used to study the free space and to identify the best trajectory with the help of a cost analysis of all possible trajectories found. Here, RRT* is adapted to fit into multi-robot systems and to allow the simultaneous planning of trajectories for multiple robots. The robustness metric of STL quantifies the respect trajectories have for STL formulas and influences the cost function of the RRT*. The impact the robustness has on the cost function is responsible for the selection of trajectories with more respect for the STL formulas. The proposed multi-agent motion planning is tested in simulations with environments containing multiple obstacles and robots. To demonstrate the impact STL has on motion planning, a comparison is made between the trajectories extracted with and without the use of STL. These simulations include specific scenarios and different numbers of robots to test the developed algorithm. They deliver asymptotically optimal solutions. Finally, we conduct some hardware experiments up until four robots to present how the developed motion planning can be implemented in real life.Rörelseplaneringsalgoritmer låter oss definiera en sekvens av konfigurationer för att guida robotar från en startposition till en slutposition medan vi tar hänsyn till robotens och miljöns begränsningar. Eftersom alla robotar och omständigheter är olika kan rörelseplanering anpassas för att passa systemets specifikationer och användarens preferenser. Temporal Logik (TL) har använts för att möjliggöra implementationer av mer komplexa uppdrag. I detta arbete är vi intresserade av att använda TL för att fastställa anslutningen mellan robotar i ett multirobotsystem, samt mellan dessa robotar och egenskaper i deras arbetsmiljö. Mer specifikt används signaltemporär logik (eng: Signal Temporal Logic) (STL) för att anpassa rörelseplanering till att respektera vissa preferenser länkade till robotens rörelsebeteende. Faktum är att användarpreferenser översätts till STL-formler som behöver respekteras av rörelseplaneringen. För att uppnå detta används den samplingsbaserade algoritmen RRT* för att studera den fria ytan och för att identifiera den bästa rörelsebanan med hjälp av en kostanalys av alla funna möjliga rörelsebanor. Här anpassas RRT* för multirobotsystem och för att tillåta planering av rörelsebanor för flera robotar samtidigt. Robushetsmåttet för STL kvantifierar respekten som banorna har för STL-formler och påverkar RRT*: s kostnadsfunktion. Påverkan som robustheten har på kostfunktionen är ansvarig för valet av rörelsebanor som till högre grad respekterar STL-formlerna. Den föreslagna röresleplaneringen för flera agenter (eng: multi-agent) testas i simuleringar av miljöer med flera hinder och robotar. För att demonstrera vilken inverkan STL har på rörelseplanering görs en jämförelse mellan rörelsebanor som ges med och utan användning av STL. Dessa simuleringar inkluderar specifika scenarion och olika antal robotar för att testa den utvecklade algoritmen. De levererar asymptotiskt optimala lösningar. Slutligen genomför vi hårdvaruexperiment upp till och med fyra robotar för att presentera hur den framtagna rörelseplaneringsalgoritmen kan implementeras i verkligheten.
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Bhavnagarwala, Azeez Jenúddin. « Voltage scaling constraints for static CMOS logic and memory cirucits ». Diss., Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/15401.
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Luria, David M. « Logic Encryption for Resource Constrained Designs ». University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1613742372174729.
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Egri, László. « The complexity of constraint satisfaction problems and symmetric Datalog / ». Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=101843.
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Constraint satisfaction problems (CSPs) provide a unified framework for studying a wide variety of computational problems naturally arising in combinatorics, artificial intelligence and database theory. To any finite domain D and any constraint language Γ (a finite set of relations over D), we associate the constraint satisfaction problem CSP(Γ): an instance of CSP(Γ) consists of a list of variables x1, x2,..., x n and a list of constraints of the form "(x 7, x2,..., x5) ∈ R" for some relation R in Γ. The goal is to determine whether the variables can be assigned values in D such that all constraints are simultaneously satisfied. The computational complexity of CSP(Γ) is entirely determined by the structure of the constraint language Γ and, thus, one wishes to identify classes of Γ such that CSP(Γ) belongs to a particular complexity class.In recent years, logical and algebraic perspectives have been particularly successful in classifying CSPs. A major weapon in the arsenal of the logical perspective is the database-theory-inspired logic programming language called Datalog. A Datalog program can be used to solve a restricted class of CSPs by either accepting or rejecting a (suitably encoded) set of input constraints. Inspired by Dalmau's work on linear Datalog and Reingold's breakthrough that undirected graph connectivity is in logarithmic space, we use a new restriction of Datalog called symmetric Datalog to identify a class of CSPs solvable in logarithmic space. We establish that expressibility in symmetric Datalog is equivalent to expressibility in a specific restriction of second order logic called Symmetric Restricted Krom Monotone SNP that has already received attention for its close relationship with logarithmic space.
We also give a combinatorial description of a large class of CSPs lying in L by showing that they are definable in symmetric Datalog. The main result of this thesis is that directed st-connectivity and a closely related CSP cannot be defined in symmetric Datalog. Because undirected st-connectivity can be defined in symmetric Datalog, this result also sheds new light on the computational differences between the undirected and directed st-connectivity problems.
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Fang, Ming. « Maintaining Integrity Constraints in Semantic Web ». Digital Archive @ GSU, 2013. http://digitalarchive.gsu.edu/cs_diss/73.
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As an expressive knowledge representation language for Semantic Web, Web Ontology Language (OWL) plays an important role in areas like science and commerce. The problem of maintaining integrity constraints arises because OWL employs the Open World Assumption (OWA) as well as the Non-Unique Name Assumption (NUNA). These assumptions are typically suitable for representing knowledge distributed across the Web, where the complete knowledge about a domain cannot be assumed, but make it challenging to use OWL itself for closed world integrity constraint validation. Integrity constraints (ICs) on ontologies have to be enforced; otherwise conflicting results would be derivable from the same knowledge base (KB). The current trends of incorporating ICs into OWL are based on its query language SPARQL, alternative semantics, or logic programming. These methods usually suffer from limited types of constraints they can handle, and/or inherited computational expensiveness.
This dissertation presents a comprehensive and efficient approach to maintaining integrity constraints. The design enforces data consistency throughout the OWL life cycle, including the processes of OWL generation, maintenance, and interactions with other ontologies. For OWL generation, the Paraconsistent model is used to maintain integrity constraints during the relational database to OWL translation process. Then a new rule-based language with set extension is introduced as a platform to allow users to specify constraints, along with a demonstration of 18 commonly used constraints written in this language. In addition, a new constraint maintenance system, called Jena2Drools, is proposed and implemented, to show its effectiveness and efficiency. To further handle inconsistencies among multiple distributed ontologies, this work constructs a framework to break down global constraints into several sub-constraints for efficient parallel validation.
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Walton, Matthew. « First-order lax logic : a framework for abstraction, constraints and refinement ». Thesis, University of Sheffield, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.299599.
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Mendler, M. « A modal logic for handling behavioural constraints in formal hardware verification ». Thesis, University of Edinburgh, 1992. http://hdl.handle.net/1842/15374.
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The application of formal methods to the design of correct computer hardware depends crucially on the use of abstraction mechanisms to partition the synthesis and verification task into tractable pieces. Unfortunately however, behavioural abstractions are genuine mathematical abstractions only up to behavioural constraints, i.e. under certain restrictions imposed on the device's environment. Timing constraints on input signals form an important class of such restrictions. Hardware components that behave properly only under such constraints satisfy their abstract specifications only approximately. This is an impediment to the naive approach to formal verification since the question of how to apply a theorem prover when one only knows approximately what formula to prove has not as yet been dealt with. In this thesis we propose, as a solution, to interpret the notion of 'correctness up to constraint' as a modality of intuitionistic predicate logic so as to remove constraints from the specification and to make them part of its proof. This provides for an 'approximate' verification of abstract specifications and yet does not compromise the rigour of the argument since a realizability semantics can be used to extract the constraints. Also, the abstract verification is separated from constraint analysis which in turn may be delayed arbitrarily. In the proposed framework constraint analysis comes down to proof analysis and a computational semantics on proofs may be used to manipulate and simplify constraints.
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Zhao, Yuting. « Answer set programming : SAT based solver and phase transition / ». View abstract or full-text, 2003. http://library.ust.hk/cgi/db/thesis.pl?COMP%202003%20ZHAOY.
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Bass, Henry Morgan. « Automatic modification of part geometries subject to manufacturing constraints using fuzzy logic ». Thesis, Virginia Tech, 1996. http://hdl.handle.net/10919/45086.
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There is frequently a need for algorithms capable of automatic modification of geometric models in response to manufacturing process constraints. Designers typically initiate product models using ideal, exact geometry; however, several non-traditional manufacturing processes frequently require slight modifications to the ideal model to accommodate various manufacturing process constraints. These modifications can be difficult, complex, and tedious to compute. For instance, metal-ceramic brazing requires adjustments to the part geometry
primarily to accommodate thermal expansion and to allow for the insertion of a narrow braze-filler gap. These adjustments depend on the particular geometry, material properties, and processing parameters. Any modification to these product model parameters necessitates extensive recomputation to reestablish a manufacturable part geometry.
This thesis demonstrates in part the integration of geometry into the overall product model by having the non-geometric parts of the product model provide feedback to the geometry by means of automatically modifying its shape. The methodology is demonstrated in a prototype model which introduces the concept of auxiliary geometric structures. In particular, the auxiliary geometric structures provide a mapping between the designer's intent and the part geometry
described in the solid model. The designer's intent is represented in a rule base for metal-ceramic brazing that is controlled by fuzzy logic. This rule base aids the user in quantifying and generating from the auxiliary geometric structures the geometric modifications needed to conform with a complex set of rules derived from both analytic and empirical work in metal-ceramic brazingMaster of Science
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Coll, Caballero Jordi. « Scheduling through logic-based tools ». Doctoral thesis, Universitat de Girona, 2019. http://hdl.handle.net/10803/667963.
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Scheduling problems consist in determining how to execute the activities of a project in order to satisfy some requirements. Such problems are ubiquitous nowadays in industry and services, but finding solutions of scheduling problems is computationally hard. The main contribution of this thesis is the presentation of efficient SAT and SMT-based methods to solve scheduling problems. More precisely we tackle the well-known problem RCPSP as well as many extensions of it. The most challenging constraints in RCPSP-based problems are resource constraints, which specify that activities must share a set of finite resources. To handle such constraints we provide efficient SAT encodings of pseudo-Boolean (PB) constraints, which take into account the existence of collateral constraints. The provided PB encodings can have application to combinatorial problems in general, not only scheduling. The systems that we present are state-of-the-art in exact scheduling solving.Un problema de scheduling consisteix en decidir com executar les activitats d'un projecte per tal de satisfer un seguit de requeriments. Aquests problemes són molt presents en els sectors de la industria i els serveis, però trobar una solució d'un problema de scheduling és computacionalment costós. La contribució principal d'aquesta tesi és presentar mètodes eficients basats en codifiacions de SAT i SMT per solucionar problemes de scheduling. Concretament ataquem el conegut problema RCPSP i diverses extensions d'aquest. Les restriccions més complexes en aquests problemes són les d'ús de recursos finits compartits entre activitats. Per tal de tractar aquestes restriccions, proporcionem codificacions eficients a SAT de restriccions pseudo-Booleanes (PB), que tenen en compte l'existència de restriccions col·laterals. Les codificacions de PB proposades són de propòsit general i poden tenir aplicació a tot tipus de problemes combinatoris. Les eines que presentem es situen en l'estat de l'art de solucionar problemes de scheduling.
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Ågren, Magnus. « Set Constraints for Local Search ». Doctoral thesis, Uppsala universitet, Avdelningen för datalogi, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8373.
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Combinatorial problems are ubiquitous in our society and solving such problems efficiently is often crucial. One technique for solving combinatorial problems is constraint-based local search. Its compositional nature together with its efficiency on large problem instances have made this technique particularly attractive. In this thesis we contribute to simplifying the solving of combinatorial problems using constraint-based local search. To provide higher-level modelling options, we introduce set variables and set constraints in local search by extending relevant local search concepts. We also propose a general scheme to follow in order to define what we call natural and balanced constraint measures, and accordingly define such measures for over a dozen set constraints. However, defining such measures for a new constraint is time-consuming and error-prone. To relieve the user from this, we provide generic measures for any set constraint modelled in monadic existential second-order logic. We also theoretically relate these measures to our proposed general scheme, and discuss implementation issues such as incremental algorithms and their worst-case complexities. To enable higher-level search algorithms, we introduce constraint-directed neighbourhoods in local search by proposing new constraint primitives for representing such neighbourhoods. Based on a constraint, possibly modelled in monadic existential second-order logic, these primitives return neighbourhoods with moves that are known in advance to achieve a decrease (or preservation, or increase) of the constraint measures, without the need to iterate over any other moves. We also present a framework for constraint-based local search where one can model and solve combinatorial problems with set variables and set constraints, use any set constraint modelled in monadic existential second-order logic, as well as use constraint-directed neighbourhoods. Experimental results on three real-life problems show the usefulness in practice of our theoretical results: our running times are comparable to the current state-of-the-art approaches to solving the considered problems.
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Le, Nguyen-Thinh [Verfasser], et Wolfgang [Akademischer Betreuer] Menzel. « Using weighted constraints to build a tutoring system for logic programming / Nguyen-Thinh Le. Betreuer : Wolfgang Menzel ». Hamburg : Staats- und Universitätsbibliothek Hamburg, 2011. http://d-nb.info/1020465204/34.
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Seshan, Amit Vishwanath 1976. « Extension of set-based inference mechanism for predicate logic design constraints with an application to automotive power window design ». Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/89277.
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Magatão, Leandro. « Mixed integer linear programming and constraint logic programming : towards a unified modeling framework ». Centro Federal de Educação Tecnológica do Paraná, 2005. http://repositorio.utfpr.edu.br/jspui/handle/1/86.
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The struggle to model and solve Combinatorial Optimization Problems (COPs) has challenged the development of new approaches to deal with COPs. In one of the front lines of such approaches, Operational Research (OR) and Constraint Programming (CP) optimization techniques are beginning to converge, despite their very different origins. More specifically, Mixed Integer Linear Programming (MILP) and Constraint Logic Programming (CLP) are at the confluence of the OR and the CP fields. This thesis summarizes and contrasts the essential characteristics of MILP and CLP, and the ways that they can be fruitfully combined. Chapters 1 to 3 sketch the intellectual background for recent efforts at integration and the main results achieved. In addition, these chapters highlight that CLP is known by its reach modeling framework, and the MILP modeling vocabulary is just based on inequalities, which makes the modeling process hard and error-prone. Therefore, a combined CLP-MILP approach suffers from this MILP inherited drawback. In chapter 4, this issue is addressed, and some "high-level" MILP modeling structures based on logical inference paradigms are proposed. These structures help the formulation of MILP models, and can be seen as a contribution towards a unifying modeling framework for a combined CLP-MILP approach. In addition, chapter 5 presents an MILP formulation addressing a combinatorial problem. This problem is focused on issues regarding the oil industry, more specifically, issues involving the scheduling of operational activities in a multi-product pipeline. Chapter 5 demonstrates the applicability of the high-level MILP modeling structures in a real-world scenario. Furthermore, chapter 6 presents a CLP-MILP formulation addressing the same scheduling problem previously exploited. This chapter demonstrates the applicability of the high-level MILP modeling structures in an integrated CLP-MILP modeling framework. The set of simulations conducted indicates that the combined CLP-MILP model was solved to optimality faster than either the MILP model or the CLP model. Thus, the CLP-MILP framework is a promising alternative to deal with the computational burden of this pipeline-scheduling problem. In essence, this thesis considers the integration of CLP and MILP in a modeling standpoint: it conveys the fundamentals of both techniques and the modeling features that help establish a combined CLP-MILP approach. Herein, the concentration is on the building of MILP and CLP-MILP models rather than on the solution process.
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Mahadevan, Srisudha. « Network Selection Algorithm for Satisfying Multiple User Constraints Under Uncertainty in a Heterogeneous Wireless Scenario ». University of Cincinnati / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1302550606.
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Ahlberg, Sofie. « Human-in-the-Loop Control Synthesis for Multi-Agent Systems under Metric Interval Temporal Logic Specifications ». Licentiate thesis, KTH, Reglerteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-251666.
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With the increase of robotic presence in our homes and work environment, it has become imperative to consider human-in-the-loop systems when designing robotic controllers. This includes both a physical presence of humans as well as interaction on a decision and control level. One important aspect of this is to design controllers which are guaranteed to satisfy specified safety constraints. At the same time we must minimize the risk of not finding solutions, which would force the system to stop. This require some room for relaxation to be put on the specifications. Another aspect is to design the system to be adaptive to the human and its environment. In this thesis we approach the problem by considering control synthesis for multi-agent systems under hard and soft constraints, where the human has direct impact on how the soft constraint is violated. To handle the multi-agent structure we consider both a classical centralized automata based framework and a decentralized approach with collision avoidance. To handle soft constraints we introduce a novel metric; hybrid distance, which quantify the violation. The hybrid distance consists of two types of violation; continuous distance or missing deadlines, and discrete distance or spacial violation. These distances are weighed against each other with a weight constant we will denote as the human preference constant. For the human impact we consider two types of feedback; direct feedback on the violation in the form of determining the human preference constant, and direct control input through mixed-initiative control where the human preference constant is determined through an inverse reinforcement learning algorithm based on the suggested and followed paths. The methods are validated through simulations.I takt med att robotar blir allt vanligare i våra hem och i våra arbetsmiljöer, har det blivit allt viktigare att ta hänsyn till människan plats i systemen när regulatorerna för robotorna designas. Detta innefattar både människans fysiska närvaro och interaktion på besluts- och reglernivå. En viktig aspekt i detta är att designa regulatorer som garanterat uppfyller givna villkor. Samtidigt måste vi minimera risken att ingen lösning hittas, eftersom det skulle tvinga systemet till ett stopp. För att uppnå detta krävs det att det finns rum för att mjuka upp villkoren. En annan aspekt är att designa systemet så att det är anpassningsbart till människan och miljön. I den här uppsatsen närmar vi oss problemet genom att använda regulator syntes för multi-agent system under hårda och mjuka villkor där människan har direkt påverkan på hur det svaga villkoret överträds. För att hantera multi-agent strukturen undersöker vi både det klassiska centraliserade automata-baserade ramverket och ett icke-centraliserat tillvägagångsätt med krockundvikning. För att hantera mjuka villkor introducerar vi en metrik; hybrida avståndet, som kvantifierar överträdelsen. Det hybrida avståndet består av två typer av överträdelse (kontinuerligt avstånd eller missandet av deadlines, och diskret avstånd eller rumsliga överträdelser) som vägs mot varandra med en vikt konstant som vi kommer att kalla den mänskliga preferens kontanten. Som mänsklig påverkan överväger vi direkt feedback på överträdelsen genom att hon bestämmer värdet på den mänskliga preferens kontanten, och direkt påverkan på regulatorn där den mänskliga preferens konstanten bestäms genom en inverserad förstärkt inlärnings algoritm baserad på de föreslagna och följda vägarna. Metoderna valideras genom simuleringar.
QC20190517
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Eriksson, Skoog Gun. « The soft budget constraint : the emergence, persistence and logic of an institution : The Case of Tanzania1967-1992 ». Doctoral thesis, Handelshögskolan i Stockholm, Internationell Ekonomi och Geografi (IEG), 1998. http://urn.kb.se/resolve?urn=urn:nbn:se:hhs:diva-652.
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The soft budget constraint - today a popular metaphor - is a paradox. In socialist economies, it implies that the state tends to bail out state-owned firms in financial trouble, in spite of the tremendous performance problems of the entire system that result. When the system broke down, the soft budget constraint was expected to disappear. However, it seems to persist, and its persistence appears to hamper the transition process itself. This study seeks an answer to this paradox. It aims at increasing our understanding of why the soft budget constraint exists. By investigating state-owned enterprises in Tanzania before, during and after socialism, the prevalence of the soft budget constraint is examined and an explanation of its existence is suggested. The approach is institutional. The soft budget constraint is defined as an informal institution and an invisible-hand explanation of its emergence, persistence and logic is applied. The study shows that the soft budget constraint emerged as an unintended consequence of the establishment of the Tanzanian socialist system in the 1970s. A behavioural solution to recurrent systemic problems was offered, and thus the soft budget constraint performed several functions. Once established, its very existence set off a cumulative process of self-generation. Four reinforcement mechanisms that accounted for its prevalence during Tanzanian socialism are identified. Its character as a behavioural rule helps to explain why it persisted during market-oriented reform, initiated in the mid-1980s. The soft budget constraint was part of the socialist heritage, was adapted to systemic change, and influenced the direction and character of this change.Diss. Stockholm : Handelshögsk.
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Karatas, Ahmet Serkan. « Analysis Of Extended Feature Models With Constraint Programming ». Phd thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/3/12612082/index.pdf.
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In this dissertation we lay the groundwork of automated analysis of extended feature models with constraint programming. Among different proposals, feature modeling has proven to be very effective for modeling and managing variability in Software Product Lines. However, industrial experiences showed that feature models often grow too large with hundreds of features and complex cross-tree relationships, which necessitates automated analysis support. To address this issue we present a mapping from extended feature models, which may include complex feature-feature, feature-attribute and attribute-attribute cross-tree relationships as well as global constraints, to constraint logic programming over finite domains. Then, we discuss the effects of including complex feature attribute relationships on various analysis operations defined on the feature models. As new types of variability emerge due to the inclusion of feature attributes in cross-tree relationships, we discuss the necessity of reformulation of some of the analysis operations and suggest a revised understanding for some other. We also propose new analysis operations arising due to the nature of the new variability introduced. Then we propose a transformation from extended feature models to basic/cardinality-based feature models that may be applied under certain circumstances and enables using SAT or BDD solvers in automated analysis of extended feature models. Finally, we discuss the role of the context information in feature modeling, and propose to use context information in staged configuration of feature-models.
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Guzmán, Michell. « On the expressiveness of spatial constraint systems ». Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLX064/document.
Texte intégralRésumé :
Les comportement épistémiques, mobiles et spatiaux sont omniprésent dans les systèmes distribués aujourd’hui. La nature intrinsèque épistémique de ces types de systèmes provient des interactions des éleménts qui en font parties. La plupart des gens sont familiarisés avec des systèmes numériques où les utilisateurs peuvent partager ses croyances, opinions et même des mensonges intentionnels (des canulars). Aussi, les modèles de ces systèmes doivent tenir compte des interactions avec d’autres de même que leur nature distribués. Ces comportements spatiaux et mobiles font part d’applications où les données se déplacent dans des espaces (peut-être imbriqués) qui sont définis par, par exemple, cercles d’amis, des groupes, ou des dossiers partagés. Nous pensons donc qu’une solide compréhension des notion d’espaces, de mobilité spatial ainsi que le flux d’information épistémique est cruciale dans la plupart des modèles de systèmes distribués de nos jours.Les systèmes de contrainte (sc) fournissent les domaines et les opérations de base pour les fondements sémantiques de la famille de modèles déclaratifs formels de la théorie de la concurrence connu sous le nom de programmation concurrent par contraintes (pcc). Les systèmes des contraintes spatiales (scs) représentent des structures algébriques qui étendent sc pour raisonner sur les comportement spatiaux et épistémiques de base tel que croyance et l’extrusion. Les assertions spatiales et épistémiques peuvent être vues comme des modalités spécifiques. D’autres modalités peuvent être utilisées pour les assertions concernant le temps, les connaissances et même pour l’analyse des groupes entre autres concepts utilisés dans la spécification et la vérification des systèmes concurrents.Dans cette thèse nous étudions l’expressivité des systèmes de contraintes spatiales dans la perspective générale du comportement modal et épistémique. Nous montrerons que les systèmes de contraintes spatiales sont assez robustes pour capturer des modalités inverses et pour obtenir de nouveaux résultats pour les logiques modales. Également, nous montrerons que nous pouvons utiliser les scs pour exprimer un comportement épistémique fondamental comme connaissance. Finalement, nous donnerons une caractérisation algébrique de la notion de l’information distribuée au moyen de constructions sur scsEpistemic, mobile and spatial behaviour are common place in today’s distributed systems. The intrinsic epistemic nature of these systems arises from the interactions of the elements taking part of them. Most people are familiar with digital systems where users share their beliefs, opinions and even intentional lies (hoaxes). Models of those systems must take into account the interactions with others as well as the distributed quality these systems present. Spatial and mobile behaviour are exhibited by applications and data moving across (possibly nested) spaces defined by, for example, friend circles, groups, and shared folders. We therefore believe that a solid understanding of the notion of space and spatial mobility as well as the flow of epistemic information is relevant in many models of today’s distributed systems.Constraint systems (cs’s) provide the basic domains and opera- tions for the semantic foundations of the family of formal declarative models from concurrency theory known as concurrent constraint programming (ccp). Spatial constraint systems (scs’s) are algebraic structures that extend cs’s for reasoning about basic spatial and epistemic behaviour such as belief and extrusion. Both spatial and epistemic assertions can be viewed as specific modalities. Other modalities can be used for assertions about time, knowledge and even the analysis of groups among other concepts used in the specification and verification of concurrent systems.In this thesis we study the expressiveness of spatial constraint systems in the broader perspective of modal and epistemic behaviour. We shall show that spatial constraint systems are sufficiently robust to capture inverse modalities and to derive new results for modal logics. We shall show that we can use scs’s to express a fundamental epistemic behaviour such as knowledge. Finally we shall give an algebraic characterization of the notion of distributed information by means of constructors over scs’s
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Reddy, Pamoori Venkateswara. « Tableau systems for tense logics : a constraint approach ». Thesis, Imperial College London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.283438.
Texte intégral
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Skolpadungket, Prisadarng. « Portfolio management using computational intelligence approaches : forecasting and optimising the stock returns and stock volatilities with fuzzy logic, neural network and evolutionary algorithms ». Thesis, University of Bradford, 2013. http://hdl.handle.net/10454/6306.
Texte intégralRésumé :
Portfolio optimisation has a number of constraints resulting from some practical matters and regulations. The closed-form mathematical solution of portfolio optimisation problems usually cannot include these constraints. Exhaustive search to reach the exact solution can take prohibitive amount of computational time. Portfolio optimisation models are also usually impaired by the estimation error problem caused by lack of ability to predict the future accurately. A number of Multi-Objective Genetic Algorithms are proposed to solve the problem with two objectives subject to cardinality constraints, floor constraints and round-lot constraints. Fuzzy logic is incorporated into the Vector Evaluated Genetic Algorithm (VEGA) to but solutions tend to cluster around a few points. Strength Pareto Evolutionary Algorithm 2 (SPEA2) gives solutions which are evenly distributed portfolio along the effective front while MOGA is more time efficient. An Evolutionary Artificial Neural Network (EANN) is proposed. It automatically evolves the ANN's initial values and structures hidden nodes and layers. The EANN gives a better performance in stock return forecasts in comparison with those of Ordinary Least Square Estimation and of Back Propagation and Elman Recurrent ANNs. Adaptation algorithms for selecting a pair of forecasting models, which are based on fuzzy logic-like rules, are proposed to select best models given an economic scenario. Their predictive performances are better than those of the comparing forecasting models. MOGA and SPEA2 are modified to include a third objective to handle model risk and are evaluated and tested for their performances. The result shows that they perform better than those without the third objective.
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Chalmers, Stuart W. « Agents and constraint logic ». Thesis, University of Aberdeen, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.401585.
Texte intégralRésumé :
Using Constraint Logic Programming and a data model approach, we provide an agent with a flexible way to plan and direct its actions and to manipulate and represent its knowledge. We use constraint solving techniques developed in the KRAFT project to provide the agent with a sophisticated reasoning and deliberation process. We explore the declarative use of constraints within a BDI Agent framework to represent knowledge as complex quantified constraints and apply these techniques to a courier scenario where cooperating agents communicate, delegate and exchange desires and information using Generalised Partial Global Planning mechanisms to solve a given set of tasks.
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Weidner, Thomas. « Probabilistic Logic, Probabilistic Regular Expressions, and Constraint Temporal Logic ». Doctoral thesis, Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-208732.
Texte intégralRésumé :
The classic theorems of Büchi and Kleene state the expressive equivalence of finite automata to monadic second order logic and regular expressions, respectively. These fundamental results enjoy applications in nearly every field of theoretical computer science. Around the same time as Büchi and Kleene, Rabin investigated probabilistic finite automata. This equally well established model has applications ranging from natural language processing to probabilistic model checking.
Here, we give probabilistic extensions Büchi\\\'s theorem and Kleene\\\'s theorem to the probabilistic setting. We obtain a probabilistic MSO logic by adding an expected second order quantifier. In the scope of this quantifier, membership is determined by a Bernoulli process. This approach turns out to be universal and is applicable for finite and infinite words as well as for finite trees. In order to prove the expressive equivalence of this probabilistic MSO logic to probabilistic automata, we show a Nivat-theorem, which decomposes a recognisable function into a regular language, homomorphisms, and a probability measure.
For regular expressions, we build upon existing work to obtain probabilistic regular expressions on finite and infinite words. We show the expressive equivalence between these expressions and probabilistic Muller-automata. To handle Muller-acceptance conditions, we give a new construction from probabilistic regular expressions to Muller-automata. Concerning finite trees, we define probabilistic regular tree expressions using a new iteration operator, called infinity-iteration. Again, we show that these expressions are expressively equivalent to probabilistic tree automata.
On a second track of our research we investigate Constraint LTL over multidimensional data words with data values from the infinite tree. Such LTL formulas are evaluated over infinite words, where every position possesses several data values from the infinite tree. Within Constraint LTL on can compare these values from different positions. We show that the model checking problem for this logic is PSPACE-complete via investigating the emptiness problem of Constraint Büchi automata.
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Wetsel, Gerhard. « Abductive and constraint logic programming ». Thesis, Imperial College London, 1997. http://hdl.handle.net/10044/1/7212.
Texte intégral
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Martin, Barnaby D. « Logic, computation and constraint satisfaction ». Thesis, University of Leicester, 2005. http://hdl.handle.net/2381/30530.
Texte intégralRésumé :
We study a class of non-deterministic program schemes with while loops: firstly, augmented with a priority queue for memory; secondly, augmented with universal quantification; and, thirdly, augmented with universal quantification and a stack for memory. We try to relate these respective classes of program schemes to well-known complexity classes and logics.;We study classes of structure on which path system logic coincides with polynomial time P.;We examine the complexity of generalisations of non-uniform boolean constraint satisfaction problems, where the inputs may have a bounded number of quantifier alternations (as opposed to the purely existential quantification of the CSP). We prove, for all bounded-alternation prefixes that have some universal quantifiers to the outside of some existential quantifiers (i.e. 2 and above), that this generalisation of boolean CSP respects the same dichotomy as that for the non-uniform boolean quantified constraint satisfaction problem.;We study the non-uniform QCSP, especially on digraghs, through a combinatorial analog - the alternating-homomorphism problem - that sits in relation to the QCSP exactly as the homomorphism problem sits with the CSP. We establish a trichotomy theorem for the non-uniform QCSP when the template is restricted to antireflexive, undirected graphs with at most one cycle. Specifically, such templates give rise to QCSPs that are either tractable, NP-complete or Pspace-complete.;We study closure properties on templates that respect QCSP hardness or QCSP equality. Our investigation leads us to examine the properties of first-order logic when deprived of the equality relation.;We study the non-uniform QCSP on tournament templates, deriving sufficient conditions for tractablity, NP-completeness and Pspace-completeness. In particular, we prove that those tournament templates that give rise to tractable CSP also give rise to tractable QCSP.
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Silva, Victor Anselmo. « Redes lógicas de Markov aplicadas ao aprendizado de classificadores automáticos de dados ». Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/3/3152/tde-18052011-151242/.
Texte intégralRésumé :
Sistemas de computação têm se tornado maiores e mais complexos com o objetivo de lidar com a vasta quantidade de dados disponíveis. Uma tarefa decisiva em tais sistemas é classificar estes dados, bem como extrair informação útil destes. Nesta dissertação, testam-se as redes lógicas de Markov como linguagem para especificação e aprendizado de classificadores automáticos de dados. Esta linguagem combina fragmentos da lógica de primeira ordem e modelos probabilísticos gráficos (redes de Markov) em uma única representação. A junção destas duas técnicas permite a modelagem de conhecimento relacional através da lógica, e também de incertezas por meio de probabilidades e grafos não-direcionados. Neste trabalho, classificadores são aprendidos segundo dois paradigmas de aprendizado de máquina: o supervisionado, foco desta dissertação, e também o aprendizado semi-supervisionado com restrições determinísticas. Para investigar a utilidade das redes lógicas de Markov no treinamento de classificadores, uma série de experimentos de aprendizado é desenvolvida a partir de bases de dados de treino reais disponíveis em repositórios na internet. Como ferramenta auxiliar nos experimentos, esta dissertação testa também o pacote Alchemy, que provê um conjunto de algoritmos para tarefas gerais de aprendizado de máquina e inferência probabilística em redes lógicas de Markov. Para mensurar o desempenho dos classificadores aprendidos, três métricas tradicionais são empregadas: acurácia, precisão e revocação. Os resultados alcançados com classificadores semi-supervisionados com restrições indicam que a linguagem ainda não é própria para este paradigma de aprendizado. Por outro lado, o êxito obtido no desempenho dos classificadores treinados de forma supervisionada sugere que as redes lógicas de Markov são um formalismo lógico-probabilístico promissor para aplicações de classificação, e devem ser objeto de pesquisas futuras.Computing systems have become larger and more complex in order to deal with the vast amount of available data. An important task in such systems is to classify these data, so as to extract useful information from them. In this dissertation, Markov logic networks are tested as a language to specify and learn automatic data classifiers. This language combines fragments of first-order logic and probabilistic graphical models (Markov networks), in a single representation. Together, both techniques allow one to model relational knowledge through a logic formalism, and uncertainty through probabilities and undirected graphs. In this work, data classifiers are learned by two machine learning paradigms: the supervised, the main focus of this dissertation, and also the semisupervised learning under deterministic constraints. To investigate the usefulness of Markov logic networks in training data classifiers, a set of experiments is developed from real databases available in repositories at the internet. As a support tool for experiments, this dissertation tests also the Alchemy package, which provides a set of algorithms for general machine learning tasks and probabilistic inference in Markov logic networks. To measure the performance of data classifiers, three traditional metrics are employed: accuracy, precision and recall. The results reached with semisupervised data classifiers indicate that the language is not yet suitable for learning based on this paradigm. On the other hand, the success achieved with classifiers trained in a supervised context suggests that Markov logic networks are a promising logical-probabilistic formalism to approach classification applications, and should be considered in future research.
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Madelaine, Florent. « Constraint satisfaction problems and related logic ». Thesis, University of Leicester, 2003. http://hdl.handle.net/2381/30524.
Texte intégralRésumé :
Feder and Vardi have proved that the class captured by a monadic fragment of existential second-order logic, MMSNP, is computationally equivalent (via randomised reductions) to the class of constraint satisfaction problems (CSP) while the latter is strictly included in the former. I introduce a new class of combinatorial problems, the so-called forbidden patterns problems (FP), that correspond exactly to the logic MMSNP and introduce some novel algebraic tools like the re-colouring that allow me to construct a normal form. This leads to a constructive characterisation of the borderline of CSP within FP: a given problem in FP is either given as a problem in CSP or we build counter-examples. I relate this result to a recent and independent work by Tardif and Nesetril which relies heavily on a correspondence between duality and density. I generalise this approach to FP. Finally, I investigate homomorphism problems for unary algebras.
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Mihalicek, Vedrana. « Serbo-Croatian Word Order : A Logical Approach ». The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1354280257.
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CATTAFI, Massimiliano. « LOGIC AND CONSTRAINT PROGRAMMING FOR COMPUTATIONAL SUSTAINABILITY ». Doctoral thesis, Università degli studi di Ferrara, 2012. http://hdl.handle.net/11392/2388775.
Texte intégralRésumé :
Computational Sustainability is an interdisciplinary field that aims to develop computational
and mathematical models and methods for decision making concerning
the management and allocation of resources in order to help solve environmental
problems.
This thesis deals with a broad spectrum of such problems (energy efficiency, water
management, limiting greenhouse gas emissions and fuel consumption) giving
a contribution towards their solution by means of Logic Programming (LP) and
Constraint Programming (CP), declarative paradigms from Artificial Intelligence
of proven solidity.
The problems described in this thesis were proposed by experts of the respective
domains and tested on the real data instances they provided. The results are encouraging
and show the aptness of the chosen methodologies and approaches.
The overall aim of this work is twofold: both to address real world problems
in order to achieve practical results and to get, from the application of LP and
CP technologies to complex scenarios, feedback and directions useful for their
improvement.
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Padmanabhuni, Srinivas. « Logic programming with stable models for constraint satisfaction ». Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0009/NQ60011.pdf.
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Pippin, William E. Jr. « Optimizing Threads of Computation in Constraint Logic Programs ». The Ohio State University, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=osu1041551800.
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Rantsoudis, Christos. « Bases de connaissance et actions de mise à jour préférées : à la recherche de consistance au travers des programmes de la logique dynamique ». Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30286.
Texte intégralRésumé :
Dans la littérature sur les bases de données, il a été proposé d'utiliser des contraintes d'intégrité actives afin de restaurer l'intégrité de la base. Ces contraintes d'intégrité actives consistent en une contrainte classique augmentée d'un ensemble d'actions de mise à jour préférées qui peuvent être déclenchées quand la contrainte est violée. Dans la première partie de cette thèse, nous passons en revue les principales stratégies de réparation qui ont été proposées dans la littérature et proposons une formalisation par des programmes de la Logique Dynamique. L'outil principal que nous employons dans notre recherche est la logique DL-PA, une variante de PDL récemment introduite. Nous explorons ensuite une nouvelle façon dynamique de réparer les bases de données et comparons sa complexité calculatoire et ses propriétés générales aux approches classiques. Dans la seconde partie de la thèse nous abandonnons le cadre propositionnel et adaptons les idées susmentionnées à des langages d'un niveau supérieur. Plus précisément, nous nous intéressons aux Logiques de Description, et étudions des extensions des axiomes d'une TBox par des actions de mise à jour donnant les manières préférées par lesquelles une ABox doit être réparée dans le cas d'une inconsistance avec les axiomes de la TBox. L'extension des axiomes d'une TBox avec de telles actions de mise à jour constitue une nouvelle TBox, qui est active. Nous nous intéressons à la manière de réparer une ABox en rapport avec une telle TBox active, du point de vue syntaxique ainsi que du point de vue sémantique. Étant donnée une ABox initiale, l'approche syntaxique nous permet de construire un nouvel ensemble d'ABox dans lequel nous identifions les réparations les mieux adaptées. D'autre part, pour l'approche sémantique, nous faisons de nouveau appel au cadre de la logique dynamique et considérons les actions de mise à jour, les axiomes d'inclusion actives et les réparations comme des programmes. Étant donné une TBox active aT , ce cadre nous permet de vérifier (1) si un ensemble d'actions de mise à jour est capable de réparer une ABox en accord avec les axiomes actifs d'aT en effectuant une interprétation locale des actions de mise à jour et (2) si une ABox A' est la réparation d'une ABox donnée A sous les axiomes actifs d'aT moyennant un nombre borné de calculs, en utilisant une interprétation globale des actions de mise à jour. Après une discussion des avantages de chaque approche nous concluons en proposant une intégration des approches syntaxiques et sémantiques dans une approche cohésiveIn the database literature it has been proposed to resort to active integrity constraints in order to restore database integrity. Such active integrity constraints consist of a classical constraint together with a set of preferred update actions that can be triggered when the constraint is violated. In the first part of this thesis, we review the main repairing routes that have been proposed in the literature and capture them by means of Dynamic Logic programs. The main tool we employ for our investigations is the recently introduced logic DL-PA, which constitutes a variant of PDL. We then go on to explore a new, dynamic kind of database repairing whose computational complexity and general properties are compared to the previous established approaches. In the second part of the thesis we leave the propositional setting and pursue to adapt the aforementioned ideas to higher level languages. More specifically, we venture into Description Logics and investigate extensions of TBox axioms by update actions that denote the preferred ways an ABox should be repaired in case of inconsistency with the axioms of the TBox. The extension of the TBox axioms with these update actions constitute new, active TBoxes. We tackle the problem of repairing an ABox with respect to such an active TBox both from a syntactic as well as a semantic perspective. Given an initial ABox, the syntactic approach allows us to construct a set of new ABoxes out of which we then identify the most suitable repairs. On the other hand, for the semantic approach we once again resort to a dynamic logic framework and view update actions, active inclusion axioms and repairs as programs. Given an active TBox aT , the framework allows to check (1) whether a set of update actions is able to repair an ABox according to the active axioms of aT by interpreting the update actions locally and (2) whether an ABox A' is the repair of a given ABox A under the active axioms of aT using a bounded number of computations by interpreting the update actions globally. After discussing the strong points of each direction, we conclude by combining the syntactic and semantic investigations into a cohesive approach
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Li, Bai. « Constraint-based reasoning in artificial intelligence ». Thesis, University of Nottingham, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282033.
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Geske, Ulrich, et Armin Wolf. « Preface ». Universität Potsdam, 2010. http://opus.kobv.de/ubp/volltexte/2010/4140/.
Texte intégralRésumé :
The workshops on (constraint) logic programming (WLP) are the annual meeting of the Society of Logic Programming (GLP e.V.) and bring together researchers interested in logic programming, constraint programming, and related areas like databases, artificial intelligence and operations research. In this decade, previous workshops took place in Dresden (2008), Würzburg (2007), Vienna (2006), Ulm (2005), Potsdam (2004), Dresden (2002), Kiel (2001), and Würzburg (2000). Contributions to workshops deal with all theoretical, experimental, and application aspects of constraint programming (CP) and logic programming (LP), including foundations of constraint/ logic programming. Some of the special topics are constraint solving and optimization, extensions of functional logic programming, deductive databases, data mining, nonmonotonic reasoning,interaction of CP/LP with other formalisms like agents, XML, JAVA, program analysis, program transformation, program verification, meta programming, parallelism and concurrency, answer set programming, implementation and software techniques (e.g., types, modularity, design patterns), applications (e.g., in production, environment, education, internet), constraint/logic programming for semantic web systems and applications, reasoning on the semantic web, data modelling for the web, semistructured data, and web query languages.
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Kuhlmann, Marco. « Towards a constraint parser for categorial type logics ». [S.l. : s.n.], 2004. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB11244178.
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Diaconescu, Razvan. « Category-based semantics for equational and constraint logic programming ». Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239361.
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Saglam, Hueseyin. « A toolkit for static analysis of constraint logic programs ». Thesis, University of Bristol, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262739.
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Ghazali, Abu Baker Mhd. « Advanced controllers for building energy management systems : advanced controllers based on traditional mathematical methods (MIMO P+I, state-space, adaptive solutions with constraints) and intelligent solutions (fuzzy logic and genetic algorithms) are investigated for humidifying, ventilating and air-conditioning applications ». Thesis, University of Bradford, 1996. http://hdl.handle.net/10454/4197.
Texte intégralRésumé :
This thesis presents the design and implementation of control strategies for building energy management systems (BEMS). The controllers considered include the multi PI-loop controllers, state-space designs, constrained input and output MIMO adaptive controllers, fuzzy logic solutions and genetic algorithm techniques. The control performances of the designs developed using the various methods based on aspects such as regulation errors squared, energy consumptions and the settling periods are investigated for different designs. The aim of the control strategy is to regulate the room temperature and the humidity to required comfort levels. In this study the building system under study is a 3 input/ 2 output system subject to external disturbances/effects. The three inputs are heating, cooling and humidification, and the 2 outputs are room air temperature and relative humidity. The external disturbances consist of climatic effects and other stochastic influences. The study is carried out within a simulation environment using the mathematical model of the test room at Loughborough University and the designed control solutions are verified through experimental trials using the full-scale BMS facility at the University of Bradford.
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Ghazali, Abu Baker MHD. « Advanced controllers for building energy management systems. Advanced controllers based on traditional mathematical methods (MIMO P+I, state-space, adaptive solutions with constraints) and intelligent solutions (fuzzy logic and genetic algorithms) are investigated for humidifying, ventilating and air-conditioning applications ». Thesis, University of Bradford, 1996. http://hdl.handle.net/10454/4197.
Texte intégralRésumé :
This thesis presents the design and implementation of control strategies for building
energy management systems (BEMS). The controllers considered include the multi PI-loop controllers, state-space designs, constrained input and output MIMO adaptive
controllers, fuzzy logic solutions and genetic algorithm techniques. The control
performances of the designs developed using the various methods based on aspects such
as regulation errors squared, energy consumptions and the settling periods are
investigated for different designs. The aim of the control strategy is to regulate the room
temperature and the humidity to required comfort levels.
In this study the building system under study is a 3 input/ 2 output system subject to external disturbances/effects. The three inputs are heating, cooling and humidification,
and the 2 outputs are room air temperature and relative humidity. The external
disturbances consist of climatic effects and other stochastic influences. The study is
carried out within a simulation environment using the mathematical model of the test
room at Loughborough University and the designed control solutions are verified
through experimental trials using the full-scale BMS facility at the University of
Bradford.
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Swain, Martin T. « Protein side-chain placement using CLP ». Thesis, University of Aberdeen, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248614.
Texte intégralRésumé :
Constraint logic programming (CLP) techniques can be used in protein side-chain placement, an important sub-task in comparative modelling. In a simple formulation values for domain variables represent rotamer side-chain conformations, and constraints represent atomic clashes. These constraints can be visualised using a "rotamer contact map", and observations made with this visualisation tool have been used to develop a strategy that overcomes limitations present in CLP caused by over-constrained residues. Null rotamers provide a mechanism that can automatically identify over-constrained residues. The use of null rotamers makes possible an iterative modelling strategy where, at each iteration, a CLP program is generated automatically; each program representing successively tighter packing constraints corresponding to larger atomic radii. Different CLP enumeration heuristics have been evaluated for use with this side-chain placement method, and it has been tested with several different rotamer libraries; a backbone-dependent rotamer library, when used with first-fail enumeration heuristics, was shown to be the most successful. Side-chain conformations predicted by this CLP method compare favourably against those predicted using other side-chain placement methods. The CLP method has been applied to two modelling problems. The first involved building models of class II MHC molecules in order to increase the utility of a peptide threading program. This program uses an allele's known or modelled 3D structure with a heuristic scoring function to predict peptides that are likely to bind to it - thus using CLP to model class II MHC alleles increases the program's utility. The second application used the CLP method to build structures of ribosome inactivating proteins (RIPs). These models were built using CLP together with comparative modelling approaches, and a model of bouganin, a recently identified wild RIF protein, has been built to help design engineered therapeutic proteins.
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Peralta, Estrada Julio C. « Analysis and specialisation of imperative programs : an approach using CLP ». Thesis, University of Bristol, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.322591.
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Lafave, Laura. « A constraint-based partial evaluator for functional logic programs and its application ». Thesis, University of Bristol, 1998. http://hdl.handle.net/1983/9ba4d239-e90c-478a-9c84-facde9a70355.
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Coghill, George MacLeod. « Mycroft : a framework for constraint based fuzzy qualitative reasoning ». Thesis, Heriot-Watt University, 1996. http://hdl.handle.net/10399/1235.
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Altunyuva, Fethi. « Implementation Of Concurrent Constraint Transaction Logic And Its User Interface ». Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607623/index.pdf.
Texte intégralRésumé :
This thesis implements a logical formalism framework called Concurrent Constraint Transaction Logic (abbr.,CCTR) which was defined for modeling and scheduling of workflows under resource allocation and cost constraints and develops an extensible and flexible graphical user interface for the framework. CCTR extends Concurrent Transaction Logic and integrates with Constraint Logic Programming to find the correct scheduling of tasks that involves resource and cost constraints. The developed system, which integrates Prolog and Java Platforms, is designed to serve as the basic environment for enterprise applications that involves CCTR based workflows and schedulers. Full implementation described in this thesis clearly illustrated that CCTR can be used as a workflow scheduler that involves not only temporal and causal constraints but also resource and cost constraints.
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Manandhar, S. K. « Relational extensions to feature logic : applications to constraint based grammars ». Thesis, University of Edinburgh, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.657261.
Texte intégralRésumé :
This thesis investigates the logical and computational foundations of unification-based or more appropriately constraint based grammars. The thesis explores extensions to feature logics (which provide the basic knowledge representation services to constraint based grammars) with multi- valued or relational features. These extensions are useful for knowledge representation tasks that cannot be expressed within current feature logics. The approach bridges the gap between concept languages (such as KL-ONE) which are the mainstay of knowledge representation languages in AI and feature logics. Various constraints on relational attributes are considered such as existential membership, universal membership, set descriptions, transitive relations and linear precedence constraints. The specific contributions of this thesis can be summarised as follows: 1. Development of an integrated feature/concept logic 2. Development of a constraint logic for so called partial set descriptions 3. Development of a constraint logic for expressing linear precedence constraints 4. The design of a constraint language CL-ONE that incorporates the central ideas provided by the above study. 5. A methodological study of the application of CL-ONE for constraint based grammars The thesis takes into account current insights in the areas of constraint logic programming, object-oriented languages, computational linguistics and knowledge representation.
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Behaegel, Jonathan. « Modèles hybrides de réseaux de régulation : étude du couplage des cycles cellulaire et circadien ». Thesis, Université Côte d'Azur (ComUE), 2018. http://www.theses.fr/2018AZUR4071/document.
Texte intégralRésumé :
La modélisation de systèmes biologiques est devenue indispensable pour comprendre les phénomènes complexes et émergents issus d'influences partiellement connues, et pour envisager de contrôler un système altéré dans le but de restaurer un comportement physiologique. Tout modèle, quel que soit son paradigme sous-jacent, fait intervenir des paramètres gouvernant sa dynamique mais les mesures expérimentales ne permettent généralement pas de les identifier et cela reste l'un des problèmes majeurs de la modélisation. Cette thèse propose une méthode automatique d'identification des paramètres dynamiques de systèmes biologiques dans un cadre de modélisation hybride. Le cadre hybride choisi découpe l'espace des phases selon l'activité des entités biologiques, et associe à chacun de ces sous-espaces une vitesse d'évolution de chacun des composants. Nous proposons une logique de Hoare en temps continu ainsi qu'un calcul de plus faible précondition qui, à partir d'observations expérimentales qualitatives et chronométriques, construit les contraintes minimales sur les paramètres du modèle pour qu’il soit compatible avec les observations. Ce calcul mène à un problème de satisfaction de contraintes sur les réels et nous montrons que celui-ci peut être résolu par le solveur AbSolute.Le prototype Holmes BioNet développé au cours de cette thèse peut non seulement automatiser le processus d'identification des valeurs des paramètres à partir des observations expérimentales, mais aussi simuler l'évolution du modèle obtenu afin de le comparer avec les traces expérimentales. Nous utilisons ce prototype pour modéliser le couplage des cycles cellulaire et circadienModelling biological systems has become instrumental to understand complex and emerging phenomena resulting from partially known influences, and to consider controlling an altered system in order to restore a physiological behaviour. Any model, independent of the underlying paradigm, involves parameters governing its dynamics. However, experimental measurements generally do not allow their identification and this remains one of the major problems of modelling. This PhD proposes an automatic method for identifying the dynamic parameters of biological systems in a hybrid modelling framework. The chosen hybrid framework splits the phase space according to the activity of the biological entities, and associates to each of these subspaces a celerity for each of the components. We introduce a continuous time Hoare logic as well as its weakest precondition calculus which, from qualitative and chronometrical experimental observations, constructs the minimum constraints on the model parameters making it compatible with the observations. This calculus leads to a Constraint Satisfaction Problem on real numbers and we show that it can be solved by the AbSolute solver.The Holmes BioNet prototype developed during this PhD can not only automate the parameter identification process from experimental data, but also simulate the evolution of the obtained model in order to compare it with experimental traces. We use this prototype to model the coupling of the cellular and circadian cycles
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Jampel, Michael Benjamin. « Over-constrained systems in CLP and CSP ». Thesis, City University London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.319633.
Texte intégral