Aim: Despite the growing trend in offering online therapy to young people this area has received little attention to date. This project therefore aims to systematically explore work in this territory by investigating the types of goals that young people approach online services with, and the challenges and opportunities that online counsellors have experienced when working with them. Methods: Initially 1,137 client articulated goals which were collated by an online youth counselling service in England between December 2013 and July 2014. Secondly, semi-structured interviews were conducted with six online counsellors who have utilised a goal-based approach to therapy with young people. Both data strands were examined by utilising the Grounded Theory Methodology. Results: The goals young people brought into therapy were conceptualized under three core categories: (1) "Intra-personal goals", (2) "Inter-personal goals" and (3) "Goals on Self relating to others". Findings from the experience of online practitioners have provided four further core-categories: (1) "The impact of goals as an ingredient of the online therapy", (2) "The effect of virtual environment working towards goals", (3) "Key themes around youth goals", and (4) "The evolution of a practitioner's therapeutic identity". Discussion: The codified types of goals proved similar to the taxonomy of goals articulated within the Berne Inventory of Therapeutic Goals. Nuances related to the online environment and age group of the clients appeared to be present and are considered. In particular, the concept of goals on "Self relating to others" provided some interesting discussion points on the nature of services provided in both online and face-to-face youth services. The practitioner views echoed the published literature reflecting on the broader experiences of working with therapeutic goals. However the lack of research into the experiences of counsellors working with therapy goals is noted. Further reflection on the findings suggested a four stage working model for goal oriented online therapy. Reflections upon the limitations of the work, implications for therapists, researchers and service providers interested in online therapeutic work are outlined.

A posteriori error estimation is an inseparable component of any reliable numerical method for solving partial differential equations. The aim of the goal-oriented a posteriori error estimates is to control the computational error directly with respect to some quantity of interest, which makes the method very convenient for many engineering applications. The resulting error estimates may be employed for mesh adaptation which enables to find a numerical approximation of the quantity of interest under some given tolerance in a very efficient manner. In this thesis, the goal-oriented error estimates are derived for discontinuous Galerkin discretizations of the linear scalar model problems, as well as of the Euler equations describing inviscid compressible flows. It focuses on several aspects of the goal-oriented error estimation method, in particular, higher order reconstructions, adjoint consistency of the discretizations, control of the algebraic errors arising from iterative solutions of both algebraic systems, and linking the estimates with the hp-anisotropic mesh adaptation. The computational performance is demonstrated by numerical experiments.

Ces travaux de recherche ont pour objectif de contribuer au développement et à l'exploitation d'outils de vérification des problèmes de mécanique linéaires dans le cadre des méthodes de décomposition de domaine sans recouvrement. Les apports de cette thèse sont multiples : * Nous proposons d'améliorer la qualité des champs statiquement admissibles nécessaires à l'évaluation de l'estimateur par une nouvelle méthodologie de reconstruction des contraintes en séquentiel et par des optimisations du calcul de l'intereffort en cadre sous-structuré.* Nous démontrons des bornes inférieures et supérieures de l'erreur séparant l'erreur algébrique (due au solveur itératif) de l'erreur de discrétisation (due à la méthode des éléments finis) tant pour une mesure globale que pour une quantité d'intérêt. Cette séparation permet la définition d'un critère d'arrêt objectif pour le solveur itératif.* Nous exploitons les informations fournies par l'estimateur et les espaces de Krylov générés pour mettre en place une stratégie auto-adaptative de calcul consistant en une chaîne de résolution mettant à profit remaillage adaptatif et recyclage des directions de recherche. Nous mettons en application le pilotage du solveur par un objectif de précision sur des exemples mécaniques en deux dimensions. / This research work aims at contributing to the development of verification tools in linear mechanical problems within the framework of non-overlapping domain decomposition methods.* We propose to improve the quality of the statically admissible stress field required for the computation of the error estimator thanks to a new methodology of stress reconstruction in sequential context and thanks to optimizations of the computations of nodal reactions in substructured context.* We prove guaranteed upper and lower bounds of the error that separates the algebraic error (due to the iterative solver) from the discretization error (due to the finite element method) for both global error measure mentand goal-oriented error estimation. It enables the definition of a new stopping criterion for the iterative solver which avoids over-resolution.* We benefit the information provided by the error estimator and the Krylov subspaces built during the resolution to set an auto-adaptive strategy. This strategy consists in sequel of resolutions and takes advantage of adaptive remeshing and recycling of search directions .We apply the steering of the iterative solver by objective of precision on two-dimensional mechanical examples.

This study is based on the critical pragmatism, which means that there is a conflict between at least two parts, in this case, the decision-makers and special needs teachers. The starting point of conflict is the implementation work of goal-oriented assessment, where the decision-makers has taken the decision that the Danish school shall implement goal-oriented assessment. The purpose of this study is to examine the six special teachers and school leaders experience and what motivates those in the implementation of goal oriented education. In order to examine the respondents' perception four individual interviews and a group interview was made. The interviews have been based on an open interview guide. Based on the critical pragmatism, the study focused on the concepts of power and deliberative communication. Power concepts is based on how decision makers used the power to decide that the goal-oriented assessment concept should be implemented. The deliberative communication based on this study examines respondents' experience gives the decision-makers the opportunity to take part of the response and use it in the development of goal-oriented assessment. The result of the study's empirical study, analysis, and discussion indicates that the majority of respondents are in favour of goal-oriented assessment, but that the implementation work has not focused on the special school. Teachers in special school needs time to implement and to break down goals in order to be able to create a customized targeted instruction for students with disabilities. Teachers in special school need education that focus on the special school’s development. One solution would be to create forums where special schools meet to develop the individual schools, classes and students. In order to justify teachers with postgraduate diploma in special needs training, it is important to begin in their practical work, by listening to and developing the change process together, which I interpret as deliberative communication. This study is important for decision makers so that they continue to work for changes and a positive development for goal-oriented assessment in the Danish special schools.

Background: Requirements engineering (RE) is the process of identifying, defining, documenting, and validating requirements. However, RE approaches are usually not applied to AI-based systems due to their ambiguity and is still a growing subject. Research also shows that the quality of ML-based systems is affected due to the lack of a structured RE process. Hence, there is a need to apply RE techniques in the development of ML-based systems.  Objectives: This research aims to identify the practices and challenges concerning RE techniques for AI-based systems in autonomous driving and then to identify a suitable RE approach to overcome the identified challenges. Further, the thesis aims to check the feasibility of the selected RE approach in developing a prototype AI-based classification system for road markings.  Methods: A combination of research methods has been used for this research. We apply techniques of interviews, case study, and a rapid literature review. The case company is Scania CV AB. A literature review is conducted to identify the possible RE approaches that can overcome the challenges identified through interviews and discussions with the stakeholders. A suitable RE approach, GR4ML, is found and used to develop and validate an AI-based classification system for road markings.  Results: Results indicate that RE is a challenging subject in autonomous driving. Several challenges are faced at the case company in eliciting, specifying, and validating requirements for AI-based systems, especially in autonomous driving. Results also show that the views in the GR4ML framework were suitable for the specification of system requirements and addressed most challenges identified at the case company. The iterative goal-oriented approach maintained flexibility during development. Through the system's development, it was identified that the Random Forest Classifier outperformed the Logistic Regressor and Support Vector Machine for the road markings classification.  Conclusions: The validation of the system suggests that the goal-oriented requirements engineering approach and the GR4ML framework addressed most challenges identified in eliciting, specifying, and validating requirements for AI-based systems at the case company. The views in the GR4ML framework provide a good overview of the functional and non-functional requirements of the lower-level systems in autonomous driving. However, the GR4ML framework might not be suitable for validation of higher-level AI-based systems in autonomous driving due to their complexity.

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Engineering secure software remains a significant challenge for today's software organizations as they struggle to understand the implications of security on their systems and develop systems that guarantee specified software security properties. The use of formal methods that are based on mathematical models has long been advocated in the development of secure systems, yet the promise of formal methods has not been realized. This is due to the additional discipline needed to formulate precisely the requirements and due complexities that often confront engineers. Further, the cost of development and the requisite learning curve of formal methods are quite high making them cost prohibitive to apply, especially for large software. The transition from requirements to design has been one of the most difficult steps in software development. Moreover, effective methods for deriving design from requirements that guarantee retention of the intended security properties remain largely unrealized on a repeatable and consistent basis. If security requirements are formalized and transformed into design using formal methods, the potential for security vulnerabilities would be diminished through better clarity, completeness, and consistency. Therefore, a requirements specification must be systematically transformable to a formal representation, and through effective formal methods the design can be derived such that the security properties are preserved and conveyed. This dissertation presents the FADES (Formal Analysis and Design for Engineering Security) approach that couples goal-oriented requirements specification with formal design specification to develop secure software in a constructive, provable and cost-effective way. To the best of our knowledge, FADES is the first security engineering approach that provides a systematic and automated bridge between semi-formal security requirements and formal design and implementation. FADES maintains the completeness and consistency of the security requirements specified with KAOS (Knowledge Acquisition for autOmated Specifications) when transformed to B formal specifications. Relaxing formality during requirements analysis enables security requirements to be better organized for producing more complete, consistent and clear requirements. The KAOS requirements model is then transformed to B, a popular formal representation used to derive and refine software systems. Security design specifications and implementation are produced using the B formal method which preserves the requisite security requirement properties. FADES treats security-specific elements in a systematic and constructive way while considering security early in the development lifecycle. Moreover, employing FADES provides better confidence for security evaluators in the evaluation of trusted software. A side effect of employing formal methods in development is the availability of sufficient traceability information at the various phases of development and maintenance allowing for more accurate impact analysis of security changes. FADES has been examined empirically both by security engineering experts and practitioners. Results obtained from the controlled experiments compare FADES to other formal methods, and show that FADES preserves security properties while maintaining better consistency, quality, and completeness. This is accomplished at a lower cost and with better results. These results have been evaluated by academic and industry experts working in the area of security and formal methods. / Ph. D.

More and more challenging designs are required everyday in today¿s industries. The traditional trial and error procedure commonly used for mechanical parts design is not valid any more since it slows down the design process and yields suboptimal designs. For structural components, one alternative consists in using shape optimization processes which provide optimal solutions. However, these techniques require a high computational effort and require extremely efficient and robust Finite Element (FE) programs. FE software companies are aware that their current commercial products must improve in this sense and devote considerable resources to improve their codes. In this work we propose to use the Cartesian Grid Finite Element Method, cgFEM as a tool for efficient and robust numerical analysis. The cgFEM methodology developed in this thesis uses the synergy of a variety of techniques to achieve this purpose, but the two main ingredients are the use of Cartesian FE grids independent of the geometry of the component to be analyzed and an efficient hierarchical data structure. These two features provide to the cgFEM technology the necessary requirements to increase the efficiency of the cgFEM code with respect to commercial FE codes. As indicated in [1, 2], in order to guarantee the convergence of a structural shape optimization process we need to control the error of each geometry analyzed. In this sense the cgFEM code also incorporates the appropriate error estimators. These error estimators are specifically adapted to the cgFEM framework to further increase its efficiency. This work introduces a solution recovery technique, denoted as SPR-CD, that in combination with the Zienkiewicz and Zhu error estimator [3] provides very accurate error measures of the FE solution. Additionally, we have also developed error estimators and numerical bounds in Quantities of Interest based on the SPR-CD technique to allow for an efficient control of the quality of the numerical solution. Regarding error estimation, we also present three new upper error bounding techniques for the error in energy norm of the FE solution, based on recovery processes. Furthermore, this work also presents an error estimation procedure to control the quality of the recovered solution in stresses provided by the SPR-CD technique. Since the recovered stress field is commonly more accurate and has a higher convergence rate than the FE solution, we propose to substitute the raw FE solution by the recovered solution to decrease the computational cost of the numerical analysis. All these improvements are reflected by the numerical examples of structural shape optimization problems presented in this thesis. These numerical analysis clearly show the improved behavior of the cgFEM technology over the classical FE implementations commonly used in industry. / Cada d'¿a dise¿nos m'as complejos son requeridos por las industrias actuales. Para el dise¿no de nuevos componentes, los procesos tradicionales de prueba y error usados com'unmente ya no son v'alidos ya que ralentizan el proceso y dan lugar a dise¿nos sub-'optimos. Para componentes estructurales, una alternativa consiste en usar procesos de optimizaci'on de forma estructural los cuales dan como resultado dise¿nos 'optimos. Sin embargo, estas t'ecnicas requieren un alto coste computacional y tambi'en programas de Elementos Finitos (EF) extremadamente eficientes y robustos. Las compa¿n'¿as de programas de EF son conocedoras de que sus programas comerciales necesitan ser mejorados en este sentido y destinan importantes cantidades de recursos para mejorar sus c'odigos. En este trabajo proponemos usar el M'etodo de Elementos Finitos basado en mallados Cartesianos (cgFEM) como una herramienta eficiente y robusta para el an'alisis num'erico. La metodolog'¿a cgFEM desarrollada en esta tesis usa la sinergia entre varias t'ecnicas para lograr este prop'osito, cuyos dos ingredientes principales son el uso de los mallados Cartesianos de EF independientes de la geometr'¿a del componente que va a ser analizado y una eficiente estructura jer'arquica de datos. Estas dos caracter'¿sticas confieren a la tecnolog'¿a cgFEM de los requisitos necesarios para aumentar la eficiencia del c'odigo cgFEM con respecto a c'odigos comerciales. Como se indica en [1, 2], para garantizar la convergencia del proceso de optimizaci'on de forma estructural se necesita controlar el error en cada geometr'¿a analizada. En este sentido el c'odigo cgFEM tambi'en incorpora los apropiados estimadores de error. Estos estimadores de error han sido espec'¿ficamente adaptados al entorno cgFEM para aumentar su eficiencia. En esta tesis se introduce un proceso de recuperaci'on de la soluci'on, llamado SPR-CD, que en combinaci'on con el estimador de error de Zienkiewicz y Zhu [3], da como resultado medidas muy precisas del error de la soluci'on de EF. Adicionalmente, tambi'en se han desarrollado estimadores de error y cotas num'ericas en Magnitudes de Inter'es basadas en la t'ecnica SPR-CD para permitir un eficiente control de la calidad de la soluci'on num'erica. Respecto a la estimaci'on de error, tambi'en se presenta un proceso de estimaci'on de error para controlar la calidad del campo de tensiones recuperado obtenido mediante la t'ecnica SPR-CD. Ya que el campo recuperado es por lo general m'as preciso y tiene un mayor orden de convergencia que la soluci'on de EF, se propone sustituir la soluci'on de EF por la soluci'on recuperada para disminuir as'¿ el coste computacional del an'alisis num'erico. Todas estas mejoras se han reflejado en esta tesis mediante ejemplos num'ericos de problemas de optimizaci'on de forma estructural. Los resultados num'ericos muestran claramente un mejor comportamiento de la tecnolog'¿a cgFEM con respecto a implementaciones cl'asicas de EF com'unmente usadas en la industria. / Nadal Soriano, E. (2014). Cartesian grid FEM (cgFEM): High performance h-adaptive FE analysis with efficient error control. Application to structural shape optimization [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/35620

Goal-Oriented Modelling Languages such as the Goal Requirements Language (GRL) have been used to reason about Design Patterns. However, the GRL is a general purpose modelling language that does not support concepts bespoke to the pattern domain. This thesis has investigated how advanced programming language techniques, namely Dependent Types and Domain Specific Languages, can be used to enhance the design and construction of Domain Specific Modelling languages (DSMLs), and apply the results to Design Pattern Engineering. This thesis presents Sif, a DSML for reasoning about design patterns as goal- oriented requirements problems. Sif presents modellers with a modelling language tailored to the pattern domain but leverages the GRL for realisation of the modelling constructs. Dependent types have influenced the design and implementation of Sif to provide correctness guarantees, and have led to the development of NovoGRL a novel extension of the GRL. A technique for DSML implementation called Types as (Meta) Modellers was developed in which the interpretation between a DSML and its host language is implemented directly within the type-system of the DSML. This provides correctness guarantees of DSML model instances during model construction. Models can only be constructed if and only if the DSML's type-system can build a valid representation of the model in the host language. This thesis also investigated design pattern evaluation, developing PREMES an evaluation framework that uses tailorable testing techniques to provide demonstrable reporting on pattern quality. Linking PREMES with Sif are: Freyja—an active pattern document schema in which Sif models are embedded within pattern documents; and Frigg—a tool for interacting with pattern documents. The proof-of-concept tools in this thesis demonstrate: machine enhanced interactions with design patterns; reproducible automation in the PREMES framework; and machine checking of pattern documents as Sif models. With the tooling and techniques presented, design pattern engineering can become a more rigorous, demonstrable, and machine checkable process.