COMPUTING (2)

Author: CARRASCO MATEOS JUAN ATANASIO.
Year: 2004.
University: NACIONAL DE EDUCACIÓN A DISTANCIA [www.uned.es].
Place of defense: E.T.S. INGENIERÍA INFORMÁTICA.
Place of preparation: E.T.S.I. INFORMATICA Q.

Summary: This thesis provides a methodology for the development of simulation environments that integrate control systems business. The methodology is easily obtained implementation, so that can be used in small systems simulation, as in full-scope simulators for large industrial plants. To that end, the methodology has been developed discussed specific practical examples. The methodology also claim to be valid for the use of increasingly numerous simulation tools providing manufacturers control systems.

Author: CHAGOYEN QUILES MÓNICA.
Year: 2004.
University: AUTÓNOMA DE MADRID [www.uam.es].
Place of defense: ESCUELA POLITÉCNICA SUPERIOR.
Place of preparation: ESCUELA POLITÉCNICA SUPERIOR.

Summary: The development of experimental techniques for high performance (such as sequencing and DNA microchips), together with the consequent development of bioinformatics and computational biology and the accumulation of large amounts of data and information have become the Molecular Biology in a science dependent largely on Information Technology. This torrent of information is necessary, almost inevitable, automate the integrated analysis of the new experimental data available. The integration of biological information has various sides, and therefore different approaches and solutions are reviewed as an introduction to the subject. The second part of the thesis presents the steps taken to overcome the lack of infrastructure for the management and storage of structural data obtained by three-dimensional electron microscopy, articulated around two scientific projects of international scope: an initial conceptualization in the database Biolmage ( integrating information from various microscopic techniques) and the creation of MDT (Electron Microscopy Database) at the European Bionformatics Institute (integrating information macromolecular structures). Finally, it presents the work (in collaboration with the San Diego Supercomputer Center) to provide tools that meet the needs of an experimental laboratory analysis and / or computer. The analysis processes are modeled using workflows (workflows), which interspersed access to sources of information (databases structured, local files, Web sites) and implementation of algorithms and / or applications.

Author: MARCO GOMEZ JORDI.
Year: 2004.
University: POLITÉCNICA DE CATALUÑA [www.upc.edu].
Place of defense: DEPARTAMENTO DE LLENGUATGES I SISTEMES INFORMÀTICS.
Place of preparation: EDIFICI C6 CAMPUS NORD.

Author: GUTIERREZ SANCHEZ GERMAN.
Year: 2004.
University: CARLOS III DE MADRID [www.uc3m.es].
Place of defense: ESCUELA POLITECNICA SUPERIOR.
Place of preparation: UNIVERSIDAD CARLOS III DE MADRID.

Summary: The design of the elements of a network of artificial neurons, the topology, it is essential, it is crucial to its proper functioning. This design is done by a human expert by the technique of trial and error. By automating the design of the topology, the process is considered as a search across all possible topologies, as genetic algorithms an appropriate tool to accomplish, and the information contained in the genotype and as it is encrypted (encoding scheme) question decisive. This thesis proposes two encoding schemes indirect, one based on the idea of cellular automata and another based on grammars bidimensionales.Se based on the chromosome contains no topology itself, but only the information needed to, through an expansion process, obtain network topology. These encodings are proposed with the aim of improving the ability generative and optimize the search process. It analyzes the generative capacity of the two encoding schemes proposed, as well as the evolutionary process to employ them on a set of application domains for the network of artificial neurons, comparing both indirect schemes among themselves, and with a direct scheme.

Author: CLARISO VILADROSA ROBERT.
Year: 2004.
University: POLITÉCNICA DE CATALUÑA [www.upc.edu].
Place of defense: Facultat d'Informàtica de Barcelona.
Place of preparation: EDIFICI C6 Campus NORD.

Summary: In many systems, the correction can be determined by comparing the responses to events of the environment with those described in the specification. In other domains, the correction depends not only on what responses occur, but when. The specification of these systems, known systems temporizados contains information temporary delays of internal actions and events of environment. This concept can be generalized system temporizados parametric, where some of the information in the temporal specification is a system parameter. Verifying a system with parameters is to determine the set of acceptable values for these parameters to ensure proper operation. However, many versions of this problem of verification are computationally expensive or even indecidibles. One important class of systems temporizados are circuits temporizados, a style of design to build high-speed circuits. A timed circuit achieves good performance, but their accuracy is guaranteed only if delays of the gates and cables meet a set of time constraints. On the other hand, designers of a circuit timed have some control over these delays. Formalize how a circuit system allows parametric timed delay the election of these delays until after verifying. So delays can be selected in accordance with the restrictions imposed by verification, avoiding conservative decisions in advance. A good choice of delays can improve the efficiency of a circuit, for example, reducing their latency. This thesis explores the verification systems temporizados parametric, with special attention to mastering circuits temporizados. The proposed methods are based on the theory of abstract interpretation, a general method for static analysis widely used in the verification of software among other problems. The contributions of this thesis belong to these two areas: verification of circuits temporizados and abstract interpretation. The first contribution is an automated method to verify circuits temporizados using symbolic delays. With respect to previous methods, this technique has several advantages as restrictions are independent of technology, better precision or a simple mechanism for validation. The experimental results show that this technique is suitable for the verification of asynchronous controllers. The temporal analysis algorithm is based on the analysis of linear relationships through convex polyhedra, a concrete analysis based on abstract interpretation. It is possible to define other analyzes changing, for example, the family of properties studied by the analysis, called abstract domain. Thus, it is possible to improve efficiency in exchange for losing accuracy. In the context of abstract interpretation, this thesis describes a new domain numerical abstraction called octahedron. This domain is based on linear inequalities with unit rates: â1, 0, or +1. Such properties capture precisely the time constraints necessary in a circuit timed. In addition, these restrictions are adequate to describe the properties of interest in other issues static analysis. That argument characterizes the domain of the abstract octaedros raises some theoretical results as the existence of a canonical form, and describes two alternative implementations, based respectively in decision diagrams and bit vectors. Both implementations achieve significant improvements in memory consumption with respect to convex polyhedra for verifying circuits tem 8 porizado 342 s, each with different time of calculation. In terms of accuracy, the results show that octaedros get an accuracy similar to the problem studied in polyhedra.

Author: ORFILA DIAZ PABON AGUSTIN.
Year: 2005.
University: CARLOS III DE MADRID [www.uc3m.es].
Place of defense: ESCUELA POLITECNICA SUPERIOR.
Place of preparation: UNIVERSIDAD CARLOS III DE MADRI.

Summary: System Detection Intrusiones (IDS) are, at present, the third most widely used security technology, surpassed only by firewalls and anti-virus. Of the evaluable features an IDS one of the most important is the effectiveness, as it shows the ability of the same to achieve a useful detection. This Doctoral Thesis states through technical analysis of the decision, a methodology for assessing the effectiveness of IDS considering the usefulness of their detections. This will provide guidance to optimally configure an IDS in a particular operating environment and sets out the steps to compare various proposals. Moreover, due to the need for automation of the processes of detection and response to incidents, it has developed a system Multiagent deliberative, taking into account the proposed methodology, has the ability both independently configured in their optimum conditions as deciding whether or not to respond to a particular event. This system allows a dynamic adaptation to the environment in question to keep in mind in their design adjustment depending upon the effectiveness of different detection techniques implemented by its agents components.

Author: GONZALEZ TABLAS FERRERES ANA ISABEL.
Year: 2005.
University: CARLOS III DE MADRID [www.uc3m.es].
Place of defense: ESCUELA POLITECNICA SUPERIOR.
Place of preparation: UNIVERSIDAD CARLOS III DE MADRID.

Summary: Services accreditation and sealed space (SASET) are among security services that have been proposed recently due to the development that location-based services have experienced in recent years. Owing perhaps to his youth, the nature of those services has not yet been defined properly. Therefore, the first objective of this thesis has been developing a framework for SASET in laying down their goals, the model under which provide, their properties and requirements to be respected because of the existing legislation Privacy. After analyzing the state of affairs existing proposals in the literature to provide SASET, it was found that they had a number of shortcomings in reference to the framework and in terms of possibilities for customization and automation of service, which will allow subscribers. Therefore, the second objective of this thesis has been the design of an architecture for the provision of these services under the previous framework and also incorporate mechanisms for the generation of personalization evidence space and the management of privacy of information space.

Author: MONTERO SIMARRO FRANCISCO.
Year: 2005.
University: CASTILLA-LA MANCHA [www.uclm.es].
Place of defense: ESCUELA POLITECNICA SUPERIOR DE ALBACETE.
Place of preparation: ESCUELA POLITECNICA SUPERIOR DE ALBACETE.

Summary: This thesis identifies trends and commonalities that can be established between Software Engineering (IS) and Interaction Persona-Ordenador (IPO). This is done to give support to the process of product development software quality. One of the key assumptions on which part of this thesis is one that provides equ the semantic gap that is identified between the two disciplines (IS and IPO) is not such, and that the real gap arises when considering stages of analysis requirements and design in the process of development of any software product. In this dissertation, the tools used to support the above go through phases: Characterize and consider the quality of a software product, meaning one that directly perceived by the user (usability). Using the expertise available, especially interaction patterns, to support the activities carried out in these phases and the remaining ones. Both elements, quality and experience, are considered together through the development of a quality model focused on usability. Experience enters the picture through the use of patterns of interaction, which is documented so generative, ie using models that can be learned and used over and over again.

Author: ALHAZOV ARTIOM.
Year: 2005.
University: ROVIRA I VIRGILI [www.urv.cat].
Place of defense: FACULTAD DE LETRAS.
Place of preparation: FACULTAD DE LETRAS.

Summary: This thesis deals with membrane systems with symbol objects as a theoretical framework of distributed parallel multiset processing systems. A halting computation can accept, generate or process a number, a vector or a word, so the system globally defines (by the results of all its computations) a set of numbers or a set of vectors or a set of words, (i.e., a language), or a function. The ability of these systems to solve particular problems is investigated, as well as their computational power, e.g., the language families defined by different classes of these systems are compared to the classical ones, i.e., regular, context-free, languages generated by extended tabled 0L systems, languages generated by matrix grammars without appearance checking, recursively enumerable languages, etc. Special attention is paid to communication of objects between the regions and to the ways of cooperation between the objects. An attempt to formalize the membrane systems is made (Section 3.4), and a software tool is constructed for the non-distributed cooperative variant, the configuration browser, i.e., a simulator, where the user chooses the next configuration among the possible ones and can go back. Different distributed models are considered. In the evolution-communication model (Chapter 4) rewriting-like rules are separated from transport rules. Proton pumping systems (Sections 4.8, 4.9) are a variant of the evolution-communication systems with a restricted way of cooperation. A special membrane computing model is a purely communicative one: the objects are moved together through a membrane. We study the computational power of membrane systems with symport/antiport of 2 or 3 objects (Chapter 5) and the computational power of membrane systems with a limited alphabet (Chapter 6). Determinism (Sections 4.7, 5.5, etc.) is a special property of computational systems; the question of whether this restriction reduces the computational power is addressed. The results on proton pumping systems can be carried over (Section 7.3) to the systems with bi-stable catalysts. Some particular examples of membrane systems applications are solving NP-complete problems in polynomial time, and solving the sorting problem.

Author: CASAS GARRIGA GEMMA.
Year: 2005.
University: POLITÉCNICA DE CATALUÑA [www.upc.edu].
Place of defense: Sala del Llac. Campus Nord.
Place of preparation: EDIFICI C6 Campus NORD.

Summary: In the field of knowledge discovery, graphs of concepts are an expressive and versatile modeling technique that provides ways to reason about information implicit in a set of data. Interesting examples of this can be found under the classical ma-the-ma-ti-cal theory of Formal Concept Analysis, dedicated to construct a lattice of concepts by defining a Galois connection on a binary relationship. Here, we will consider the more complex case where data comes in a set of structured objects; e.g. a set of sequences, trees or even of graphs. As a natural step towards the general characterization, we first focus on the mining of sequential data and, for this case, we contribute with the formalization of a lattice of closed sets of sequences. This lattice turns out to be an interesting combinatorial object from where to derive justified methods for current sequential mining problems. The first set of results from the lattice focuses on the characterization of logical implications with order. We propose a notion of association rules and prove that they can be formally justified by a purely logical characterization, namely, a natural notion of empirical Horn approximation for ordered data, which involves background Horn conditions; these ensure the consistency of the propositional theory obtained with the ordered context. We also discuss a general method to calculate these rules that can be easily incorporated into any algorithm of discovering closed sequential patterns. The second set of results corresponds to the identification of partial order structures from the input sequences. The combinatorial nature of this problem makes the classical algorithmic solutions incur in a substantial overhead, thus, remaining it to be still a challenging task. Here we contribute by proving that the maximal paths of the closure of such partial orders can be derived from the closed sets of sequences of our lattice. This theoretical result allows for the construction of partial orders by gluing the proper closed sequential patterns into higher-level structures. The main proof resorts to basic operations of category theory. Finally, the thorough analysis of the sequential case will provide new insights into the mining of other structured data without cycles. A detailed empirical validation justifies that our theoretical contributions produce appealing results also in practice.

Author: ROSELL ROIG VICENTE LUIS.
Year: 2005.
University: POLITÉCNICA DE VALENCIA [www.upv.es].
Place of defense: UNIVERSIDAD POLITÉCNICA DE VALENCIA.
Place of preparation: UNIVERSIDAD POLITÉCNICA DE VALENCIA.

Summary: In the field of computer graphics one of the major topics of study is speeding up and improving the quality to get realistic scenes. In recent years research has focused on interactive environments and animations with a high number of elements in the scene. One of the techniques performed best quality in the final image is the method of radiosity. With this component is calculated diffuse light. The disadvantage of the method compared to others is the computational cost of the program, particularly the phase that includes the calculation of form factors. In this thesis is a comprehensive study of existing methods for calculating form factor, especially those that are based on the projection of the environment. It also presents new calculation methods that enhance and accelerate the results of the previous projecting only once the environment. It studies the application of one of these methods in environments with natural lighting and vegetation. A new general method can be applied to any system design calculation form factor based on stereoscopy. With this algorithm can be improved image quality generated without increasing excessively time. Another advantage of this method is that its cost is independent of the number of elements in the scene. It describes two new methods of calculating the acceleration form factor for interactive environments and animations. With these methods exploits the information already calculated both pro and greatly reduces the time of calculation. And to accelerate further applies a technique of stereoscopy with that produced surprising results.

Author: BAÑULS POLO MARIA CARMEN.
Year: 2005.
University: POLITÉCNICA DE VALENCIA [www.upv.es].
Place of defense: UNIVERSIDAD POLITÉCNICA DE VALENCIA.
Place of preparation: UNIVERSIDAD POLITÉCNICA DE VALENCIA.

Summary: The distributed systems are working paramount importance among information systems, because of their potential capabilities of fault tolerance and scalability, allowing its relevance to current applications, increasingly demanding. Moreover, the development of distributed applications also presents particular difficulties, precisely in order to offer scalability, fault tolerance and high availability which are its advantages. So it is very useful to have distributed components specifically designed to provide a lower level, a set of well-defined services, on which applications at the highest level can build their own semantic easier. It is the case of services aimed at groups of widespread use by distributed applications, which allow escape of the details of communications. These services provide basic primitives for communication between two members of the group or, in particular, the transmission of messages to the whole group, with specific guarantees. A particular case of service-oriented groups constituent services group membership, which focuses this thesis. The services group membership provides its users with an image of a set of processes or machinery of the system that remain connected simultaneously and correct. Moreover, the various participants receive this information with specific guarantees of consistency. Thus, the services belonging to constitute a fundamental component for the development of communication systems and other groups distributed applications. The problems of belonging to groups has been widely tried in the literature both from a theoretical and practical, and there are many accomplishments of membership services usable. Despite this, the definition of the problem is not unique. On the other hand, depending on the particular system which is designed for the service are required for this or other guarantees. The original specifications and implementations were focused on traditional scenarios, where a small number of nodes were interconectaba through networks with relatively few failures and behavioral well-known (typically local area networks). However, with the development of modern systems, the Internet, the spread of wireless communications, and so on. Has become predominant other more dynamic distributed systems for distributed services which are not desirable classics. For that reason, we have developed in recent years services group membership on purpose to other environments. In this paper we focus on the specification and implementation services group membership for certain dynamic systems of interest with regard to the development of highly available applications. Specifically, we studied three types of scenarios.

Author: TAVARES DE ARAUJO CESARINY CARLOS.
Year: 2005.
University: POLITÉCNICA DE VALENCIA [www.upv.es].
Place of defense: UNIVERSIDAD POLITÉCNICA DE VALENCIA.
Place of preparation: UNIVESIDAD POLITÉCNICA DE VALENCIA.

Author: DÍAZ RAMÍREZ ARNOLDO.
Year: 2005.
University: POLITÉCNICA DE VALENCIA [www.upv.es].
Place of defense: UNIVERSIDAD POLITÉCNICA DE VALENCIA.
Place of preparation: UNIVERSIDAD POLITÉCNICA DE VALENCIA.

Summary: After more than 25 years of intensive research, planning-time systems has shown that a transition from an infrastructure based on cyclic executive, planning models more flexible, such as planning priorities based on static and dynamic planning non-critical tasks, and planning feedback, to name a few. Despite this, only a few currently planning policies are available for the implementation of systems-time. For example, most of the existing-time operating systems provide only fixed-based planning priorities. However, not all the requirements of the applications-time can be satisfactorily handled exclusively using static planning. There are systems consisting of critical tasks and criticisms that are not planned how best to use planning based on dynamic priorities. Furthermore, it has been shown that the dynamic planning allows greater use of system resources. In recent years, several authors have published various schemes to integrate new planning policies to an operating system. Some propose that the new services are planning to implement user level, thus avoiding the internal structure of the operating system has to be amended, and offering an opportunity to implement and test many of the results generated by research work the area planning systems-time. Among related works published to date, highlights the Planning Model for Defined by the user, Village proposed by Mario and Michael González-Harbour. The model provides an Application Program Interface (API) that allows planners to create and use user-level in a manner consistent with the planning model proposed by POSIX. This thesis focuses on the study of the definition of user-level planners in-time systems, and in particular in the study of model for planning user defined compatible with POSIX, to identify problems and propose unresolved some extensions to the model. Besides proposing an implementation strategy that minimizes overhead, in this thesis proposes an extension to the interface model to simplify the implementation of applications-time, to provide portability and serve as a reference for the creation and use of planners a user level.

Author: MANJÓN HERRERA JOSÉ VICENTE.
Year: 2005.
University: POLITÉCNICA DE VALENCIA [www.upv.es].
Place of defense: UNIVERSIDAD POLITÉCNICA DE VALENCIA.
Place of preparation: UNIVERSIDAD POLITÉCNICA DE VALENCIA.

Summary: The segmentation of brain magnetic resonance imaging is a very useful tool in the diagnosis and monitoring of many diseases of the central nervous system. This thesis presents the various problems that this kind of technique takes partners as well as various strategies for solving some of the most important. The first chapter presents the status of the brain segmentation techniques and the challenges still present in the same. The third examines the MRI image model which will allow addressing the challenges of a more coherent. The fourth chapter examines the problem of inhomogenidad signal in MRI images and proposes a new method for correction. In chapter five is the problem of classification of brain tissue and analyzed various proposals aimed at the same robust classification: Finally, in chapter six presents general conclusions of this thesis as well as lines for the future.

Author: Puentes Calvo Juan Francisco.
Year: 2005.
University: A CORUÑA [www.udc.es].
Place of defense: Facultad de Informática.
Place of preparation: Facultad de Informática.

Summary: The large increase in the volume of information available online for a few decades ago needed, increasingly, information retrieval techniques with the aim to manage, retrieve and filter the information available through these means. The current lines of research have discovered that there is a bottleneck in the channel response architectures distributed information retrieval, mainly due to the large number of partial answers and their subsequent influence on the architecture of communications and on brokers user. On the one hand, if the number of disminuimos partial responses generated by each server query disminuimos accuracy of the final response, on the other hand, if we design an architecture that supports communications traffic we get a clear bottleneck in ordering partial results in the user brokers in order to select the final answer. The solution suggested by this paper consists of a communications architecture implemented filtered through programmable nodes, which make up one subnet that has the ability to process in a transparent way traffic crosses, with the goal of reducing the cardinality of partial answers. So the main advantage of using programmable nodes rather than, for example, brokers is transparency, which makes it possible to build infrastructures channels response highly flexible and facilmetne modified at runtime. This paper analyzes, designs, makes, measured and discussed a set of algorithms filtering partial responses (that traditionally used in areas of information retrieval and the family of algorithms BGFAST-Buffered and Grooved Filter with Adaptative and Scaled Threshold) plus a programmable node architecture (VAIN-Value Added Indepent Node), which together allow for a predictable and reduce significantly the cardinality of partial responses, reaching improvements, according to our calculations, 64% compared to a channel response and not centralized filtering .

Author: VILLARROEL ACEVEDO RODOLFO HUMBERTO.
Year: 2005.
University: CASTILLA-LA MANCHA [www.uclm.es].
Place of defense: ESCUELA SUPERIOR DE INFORMATICA.
Place of preparation: ESCUELA SUPERIOR DE INFORMATICA.

Summary: THESIS ON THIS IS PRESENTING AN APPROXIMATION MODELING FOR THE CONCEPT OF DATA STORAGE OF INSURANCE. UTILIZAREMOS THIS TERM DOING A SIMILARITY WITH THE CONCEPT OF DATABASES SAFE TO HISTORICAMENTE BE REFERRED TO DATABASES MULTILEVEL, WHICH CONTAINING OBJECTS WITH DIFFERENT LEVELS OF CONFIDENTIALITY AND SUBJECT TO REGISTER DIFFERENT HABILITACIONES. ASPECTS TO BE CONSIDERED IN THIS THESIS ARE THE FOLLOWING: -ESTUDIO COMPARISON OF PROPOSALS OF THE EXISTING MODELING AND MULTIDIMENSIONAL MODELING OF SECURITY IN THE DESIGN OF SYSTEMS. DEFINITION OF AN APPROXIMATION-BASED MODELS FOR THE DEVELOPMENT OF DATA STORAGE TO REPRESENT THE STRUCTURE, AND RESTRICTIONS ON THE FUNCTIONALITY ALMACEN EXCLUDING DETAILS OF A SPECIFIC PLATFORM DETERMINED. - DEFINITION OF A MODEL OF SECURITY, WHICH CONSIDERE THE AUDIT AND ACCESS CONTROL FOR DATA STORAGE. - DEFINITION OF AN EXTENSION OF UML MODELING FOR THE CONCEPT OF DATA STORAGE OF INSURANCE. - DEFINITION OF MECHANISMS OF TRANSFORMATION OF MODELS TO A CONCEPTUAL PLATFORM IS ORACLE LABEL AS SPECIFIED SECURITY -APLICACION OF THE PROPOSAL TO A CASE STUDY FOR CONTRASTAR THE VALIDITY OF MODELS OFFERED -DESARROLLO OF A PROTOTYPE THAT WE SUPPORT AND MODELING THE CONCEPT OF AUTOMATED DATA STORAGE OF INSURANCE.

Author: PAREDES VELASCO MAXIMILIANO.
Year: 2005.
University: CASTILLA-LA MANCHA [www.uclm.es].
Place of defense: ESCUELA SUPERIOR DE INFORMÁTICA.
Place of preparation: ESCUELA SUPERIOR DE INFORMÁTICA.

Summary: Over recent decades, technology has driven a revolution in education. Currently, the use of computers in the aftermath is not integrated into the classroom and its use is relegated to certain sections or areas of the learning process. The society demand new technological solutions for learning with a nomadic spirit that make the learning process is possible anywhere, anytime. Considering the principles of genetic paradigms CSCL (Computer Supported Collaborative Learning), ubiquitous computing and CSCWr (Computer Supported Collaborative Writing) propose a solution which puts computational resources in harmony with the process of learning from the social perspective, proposing the use of new mobile devices for user interaction, improving their integration into the classroom environment and meet the changing needs of society. As a result of the investigation conducted propose e-CLUB, a general framework for designing systems for the realization of ubiquitous generic collaborative learning experiences. This generic framework we have implemented in learning English as a second language, ESL (English as the Second Language), using the composition of text as teaching method supported by brainstorming process. As a result of this work suggest classroom, an environment of aprendizjae collaborative tasks of writing through group using mobile devices. This environment makes a contribution technological, educational and collaborative. It includes a methodology for writing collaborative learning called MECA, a modeling product and the relationship of the group that produced in the activity of aprendizjae and a platform for ubiquitous computing that provides various software tools. The platform has been designed with a centralized architecture that supports the synchronization of distributed work in a scenario of mobile computing. This architecture provides for interaction of different devices: Slate Projection / Edition, Tablet PC, PC and PDA with wireless communication capability (WLAN b luettoth and IR). Tools CLASSROOM implement strategies sensitivity to the context and represent a comprehensive proposal of the learning process, from the definition curriculum until analysis of the experience, allowing the user interacts with the system before, during and after the class, inside and outside the classroom. These tools allow you to specify the topics of composition, facilitate the sharing and discussion of contributions textual and analyzed and evaluated the learning process, the solutions generated and social relations that appear. The system design has been validated and refined through a process of experimentation and evaluation literativo. Experiments have been conducted which have ranged from the valuation express different functionalities in the laboratory to the operation of the system in real contexts with students interacting with mobile devices performing a text layout.

Author: ARMENDÁRIZ IÑIGO JOSÉ ENRIQUE.
Year: 2005.
University: PÚBLICA DE NAVARRA [www.unavarra.es].
Place of defense: ESCUELA TÉCNICA SUPERIOR DE INGENIEROS INDUSTRIALES Y TELECOMUNICACIÓN.
Place of preparation: UNIVERSIDAD PÚBLICA DE NAVARRA.

Summary: The aim of this thesis has been the design and implementation of the protocols replication based O2PL for a new architecture middleware replication of databases called MADIS. This architecture is characterized by providing a JDBC interface to the user applications and support, by modifying the schema of the database, to a wide range of protocols replication. The latter allows isolate concurrency control (managed by the system manager databases) control replication (run by the replication protocol used in MADIS). The two protocols developed BRP and ERP, formalizes a system using state-transition that facilitates checking correction (1-copy-Serizlizable). Additionally, formalized a new protocol for MADIS, TORPE based on the delivery order totaling broadcasts by communication systems group, in order to compare the behavior of this type of protocols, which are widely used in the literature today, with the two previous protocols. The implementation of these three protocols MADIS verify theoretical assumptions posed for BRP and ERP in their testing and correction shows that proceloso total order are generally the best choice for the replication of databases. However, it notes that the protocol ERP is the best choice for environments with low loads within our test environment. Finally, a recovery protocol, designed as a transitional state, which applies to both the BRP as ERP. This protocol uses the timing of hearings for managing the recovery of failed nodes establishing recovery partitions are created on the node recuperating and recover, so that the latter can begin to address user transactions but has not finished recover. The aim is to abort the lowest number of transactions being executed in the system.

Author: TORRENTE MORENO SABINA.
Year: 2005.
University: NACIONAL DE EDUCACIÓN A DISTANCIA [www.uned.es].
Place of defense: E.T.S. INGENIEROS INDUSTRIALES.
Place of preparation: UNIVERSIDAD NACIONAL DE EDUCACIÓN A DISTANCIA.

Summary: In order to ensure the sustained development of the Information Society is a need to provide mechanisms for access to information in accordance with the freedoms of a democratic system. At present, an Internet user can access an infinite universe of information from anywhere in the world without restrictions of space or time. The first major incident of computer security, starring Robert T. worm Morris, dating from 1998. However, 16 years later, are detected and daily published new vulnerabilities that highlight the weakness of information systems. Intruders, attackers or simply curious (with various motives) are trying to undermine the systems. That's why, it is vital to strengthen information systems, will be allowed so that transform a system initially "weak" in a "reliable" commensurate with the needs of their users and the sensitivity of the information they handle. At present we can not guarantee the security of an information system based on the tools and mechanisms. It is therefore necessary to establish a cooperative approach to security in which different solutions work together by combining their strengths and mitigating its weaknesses. In order to focus part of the research presented in this thesis, has made a detailed study of the concept of intrusion detection system (IDS, Intrusion Detection System), as well as the evolution of these systems and techniques applied from their origins (late 80s) to the present. A primary objective of this thesis is to present an original approach for detecting intrusions inspired by the immune system of vertebrates. In this thesis argues that the characteristics that make the immune system a defensive mechanism efficient and reliable are applicable to information systems. For this research has developed a prototype based on neural networks (similar to lymphocytes in the immune system) that specialize in detecting patterns of behavior potentially intrusive. As a result of first objective of this thesis has designed a prototype original detection systems instructions called SANNA (Sensing System instrusiones of Scope node based on Artificial Neural Networks). The prototype SANNA implements a system for detecting anomalies field node based on neural networks specialized in the detection of potential threats against known and unknown system. The second objective of this research project is to verify the suitability of the model for intrusion detection system proposed in this thesis. This has been carefully reviewed the design and implementation of the prototype SANNA, and this prototype has been applied to a test environment, defined on the basis of data provided by the project "The 1998 DARPA Intrusion Detection Evaluation Program." The ultimate objective of this thesis is to analyze the results of the tests conducted with the prototype SANNA and compile the lessons learned on the applicability of neural networks to the problem of detecting instrusiones.