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.

While several approaches exist for modeling goals and business processes in organizations, the relationships between these two views are often not well defined. This inhibits the effective reuse of available knowledge in models. This thesis aims to address this issue through the introduction of a Goal-oriented Pattern Family (GoPF) framework that helps constructing business process models from organization goals while expanding these goals, establishing traceability relationships between the goal and process views, and improving reusability. Methods for extracting domain knowledge as patterns, which are composed of goal model building blocks, process model building blocks, and their relationships, and for maintaining the patterns over time are also presented. The GoPF framework provides the infrastructure for defining pattern families, i.e., collections of related patterns for particular domains. The foundation of GoPF is formalized as a profile of the User Requirements Notation, a standard modeling language that supports goals, scenarios, and links between them. A method for the use of GoPF is defined and then illustrated through a case study that targets the improvement of patient safety in healthcare organizations. The framework and the extraction/maintenance methods are also validated against another case study involving aviation security in a regulatory environment. The GoPF framework is expected to have a positive impact on the scientific community through the formalization, evolution, and reuse of patterns in domain-specific business domains. From an industrial viewpoint, this framework will also help intermediary organizations (such as consulting firms) who are required to repeatedly create and document goal and process models for other organizations in their business domain.

Background: Business process compliance management has recently attracted a lot of attention in both business and academia as it enables organizations to not only control and monitor their business processes from a legal point of view but also to avoid financial penalties and undesirable consequences to their reputation. Objective: This thesis aims to provide a framework that would enable organizations to: 1- Discover business processes that violate regulations, laws and policies; 2- Discover the importance level of business processes based on the organization’s goals; 3- Determine the impact of compliance-related process modifications on business goals, including conflicting goals between stakeholders, and on policies; and 4- Enable organizations to measure the level of business process compliance for one or multiple policies. Methodology: A systematic literature review in the area of goal-oriented business process compliance management and measurement has been conducted, which showed that balancing legal compliance obligations with business objectives remains a difficult challenge. A new Indicator-based Policy Compliance Framework (IPCF), which combines policy and rule models together with models capturing business goals (with their relative importance to the organization) and business processes, has been proposed. This framework builds on the User Requirements Notation (URN), which is the first international standard to combine goal modeling with scenario modeling. The intents and objectives of policies have been modeled, as well as the goals and business processes of organizations, and indicators are used to measure the compliance level of policies. This enables the detection of non-compliant business processes and the evaluation of the impact of compliance-related process modifications on business goals. Human resource policies and business processes are used as an example to illustrate the method. Aerodrome security regulations and business processes are then used to validate the method in a real-life environment. Comparisons to related work, evaluation against different sets of criteria, and tool support complement the framework validation. Results: The Indicator-based Policy Compliance Framework enables organizations to discover business processes that violate policies as well as other types of rules, regulations, and laws. Guidelines for modeling legal text with URN’s Goal-oriented Requirement Language (GRL) are proposed. Furthermore, IPCF helps determine the impact of compliance-related process modifications on business goals, including conflicting goals between stakeholders, and on policies. In addition, as policies sometimes apply differently to different types of organizations, a new profile for GRL, with suitable stereotypes, well-formedness constraints, and a modified analysis algorithm defined for GRL model families is used to evaluate the satisfaction level of individual goal models that are members of a larger family model. Finally, the proposed IPCF enables organizations to measure the level of business process compliance for one or multiple policies, and such measures can be visualized directly in URN models but also through interactive Business Intelligence portals, for a wider diffusion.

<p>I chose to study how the Swedish Air force carries out their work with setting goals for their work to improve flight safety and compare this with how the Swedish nuclear power plant Forsmark performs their work with improving nuclear safety. The study showed that both organisations have a lot to improve on in their ways of how to work. Especially when it comes to engaging the employees in the process, both in letting the employees be a part of coming up with areas to work on and in letting the employees evaluate which progress that has been made. It also showed that both organisations need to improve their methods for evaluating the work that has been done. This is especially important for the Air Force which evaluates on many levels and locations and did not have a set standard for how to conduct the evaluation. Although, Forsmark also needed to improve but on how to conduct the evaluation on more than one level in the organisation, allowing more people into the evaluation process and maybe letting someone not part of the process be a part of the evaluation to see things from a different perspective. Also, Forsmark had goals set which did not have a set time for when to evaluate them, which is another criteria for success.</p>

I chose to study how the Swedish Air force carries out their work with setting goals for their work to improve flight safety and compare this with how the Swedish nuclear power plant Forsmark performs their work with improving nuclear safety. The study showed that both organisations have a lot to improve on in their ways of how to work. Especially when it comes to engaging the employees in the process, both in letting the employees be a part of coming up with areas to work on and in letting the employees evaluate which progress that has been made. It also showed that both organisations need to improve their methods for evaluating the work that has been done. This is especially important for the Air Force which evaluates on many levels and locations and did not have a set standard for how to conduct the evaluation. Although, Forsmark also needed to improve but on how to conduct the evaluation on more than one level in the organisation, allowing more people into the evaluation process and maybe letting someone not part of the process be a part of the evaluation to see things from a different perspective. Also, Forsmark had goals set which did not have a set time for when to evaluate them, which is another criteria for success.