Software Product Lines (SPLs) and Software Ecosystems (SECOs) are approaches to capturing families of closely related software systems in terms of common and variable functionality (variability in space). SPLs and especially SECOs are subject to software evolution to adapt to new or changed requirements resulting in different versions of the software family and its variable assets (variability in time). Both dimensions may be interconnected (e.g., through version incompatibilities) and, thus, have to be handled simultaneously as not all customers upgrade their respective products immediately or completely. However, there currently is no integrated approach allowing variant derivation of features in different version combinations. In this thesis, remedy is provided in the form of an integrated approach making contributions in three areas: (1) As variability model, Hyper-Feature Models (HFMs) and a version-aware constraint language are introduced to conceptually capture variability in time as features and feature versions. (2) As variability realization mechanism, delta modeling is extended for variability in time, and a language creation infrastructure is provided to devise suitable delta languages. (3) For the variant derivation procedure, an automatic version selection mechanism is presented as well as a procedure to derive large parts of the application order for delta modules from the structure of the HFM. The presented integrated approach enables derivation of concrete software systems from an SPL or a SECO where both features and feature versions may be configured.

Modern business applications are getting increasingly distributed as multi-tenant software as a service (SaaS). This leads to new challenges in terms of quality assurance, because all customers are directly affected by software changes. The resulting problem is to proactively determinate evolutionary effects. Because SaaS applications are often realized in the sense of a software product line, this thesis examines ways of using feature models to face the mentioned problem. For this purpose, two approaches are analyzed: extended feature models with quality attributes annotated per feature and the analysis of structural aspects of feature models and corresponding concrete configurations. The presented attributed feature model approach measures the quality of concrete configurations to make configurations comparable according to specific quality goals. Criteria are elicited for when configurations can be compared to draw helpful conclusions. The structural approach focuses economic questions that are quality assurance related, such as identifying features that none of the tenants selected in their application configurations. Furthermore, three algorithms are presented that demonstrate the structural analysis approach to gather information relevant to quality assurance.

To offer customisable software, there are two main concepts yet: software product lines that allow the product customisation based on a fixed set of variability and software ecosystems, allowing an open product customisation based on a common platform. Offering a software family that enables external developers to supply software artefacts means to offer a common platform as part of an ecosystem and to sacrifice variability control. Keeping full variability control means to offer a customisable product as a product line, but without the support for external contributors. This thesis proposes a third concept of variable software: partly open software families. They combine a customisable platform similar to product lines with controlled openness similar to ecosystems. As a major contribution of this thesis a variability modelling concept is proposed which is part of a variability management for these partly open software families. This modelling concept is based on feature models and extends them to support open variability modelling by means of interfaces, structural interface specifications and the inclusion of semantic information. Additionally, the introduction of a rights management allows multiple contributors to work with the model. This is required to enable external developers to use the model for the concrete extension development. The feasibility of the proposed model is evaluated using a prototypically developed modelling tool and by means of a case study based on a car infotainment system.

Software Product Lines (SPLs) and Software Ecosystems (SECOs) are approaches to capturing families of closely related software systems in terms of common and variable functionality (variability in space). SPLs and especially SECOs are subject to software evolution to adapt to new or changed requirements resulting in different versions of the software family and its variable assets (variability in time). Both dimensions may be interconnected (e.g., through version incompatibilities) and, thus, have to be handled simultaneously as not all customers upgrade their respective products immediately or completely. However, there currently is no integrated approach allowing variant derivation of features in different version combinations. In this thesis, remedy is provided in the form of an integrated approach making contributions in three areas: (1) As variability model, Hyper-Feature Models (HFMs) and a version-aware constraint language are introduced to conceptually capture variability in time as features and feature versions. (2) As variability realization mechanism, delta modeling is extended for variability in time, and a language creation infrastructure is provided to devise suitable delta languages. (3) For the variant derivation procedure, an automatic version selection mechanism is presented as well as a procedure to derive large parts of the application order for delta modules from the structure of the HFM. The presented integrated approach enables derivation of concrete software systems from an SPL or a SECO where both features and feature versions may be configured.:I. Context and Preliminaries 1. The Configurable TurtleBot Driver as Running Example 1.1. TurtleBot: A Domestic Service Robot 1.2. Configurable Driver Functionality 1.3. Software Realization Artifacts 1.4. Development History of the Driver Software 2. Families of Variable Software Systems 2.1. Variability 2.1.1. Variability in Space and Time 2.1.2. Internal and External Variability 2.2. Manifestations of Configuration Knowledge 2.2.1. Variability Models 2.2.2. Variability Realization Mechanisms 2.2.3. Variability in Realization Assets 2.3. Types of Software Families 2.3.1. Software Product Lines 2.3.2. Software Ecosystems 2.3.3. Comparison of Software Product Lines and Software Ecosystems 3. Fundamental Approaches and Technologies of the Thesis 3.1. Model-Driven Software Development 3.1.1. Metamodeling Levels 3.1.2. Utilizing Models in Generative Approaches 3.1.3. Representation of Languages using Metamodels 3.1.4. Changing the Model-Representation of Artifacts 3.1.5. Suitability of Model-Driven Software Development 3.2. Fundamental Variability Management Techniques of the Thesis 3.2.1. Feature Models as Variability Models 3.2.2. Delta Modeling as Variability Realization Mechanism 3.2.3. Variant Derivation Process of Delta Modeling with Feature Models 3.3. Constraint Satisfaction Problems 3.4. Scope 3.4.1. Problem Statement 3.4.2. Requirements 3.4.3. Assumptions and Boundaries II. Integrated Management of Variability in Space and Time 4. Capturing Variability in Space and Time with Hyper-Feature Models 4.1. Feature Models Cannot Capture Variability in Time 4.2. Formal Definition of Feature Models 4.3. Definition of Hyper-Feature Models 4.4. Creation of Hyper-Feature Model Versions 4.5. Version-Aware Constraints to Represent Version Dependencies and Incompatibilities 4.6. Hyper-Feature Models are a True Extension to Feature Models 4.7. Case Study 4.8. Demarcation from Related Work 4.9. Chapter Summary 5. Creating Delta Languages Suitable for Variability in Space and Time 5.1. Current Delta Languages are not Suitable for Variability in Time 5.2. Software Fault Trees as Example of a Source Language 5.3. Evolution Delta Modules as Manifestation of Variability in Time 5.4. Automating Delta Language Generation 5.4.1. Standard Delta Operations Realize Usual Functionality 5.4.2. Custom Delta Operations Realize Specialized Functionality 5.5. Delta Language Creation Infrastructure 5.5.1. The Common Base Delta Language Provides Shared Functionality for all Delta Languages 5.5.2. Delta Dialects Define Delta Operations for Custom Delta Languages 5.5.3. Custom Delta Languages Enable Variability in Source Languages 5.6. Case Study 5.7. Demarcation from Related Work 5.8. Chapter Summary 6. Deriving Variants with Variability in Space and Time 6.1. Variant Derivation Cannot Handle Variability in Time 6.2. Associating Features and Feature Versions with Delta Modules 6.3. Automatically Select Versions to Ease Configuration 6.4. Application Order and Implicitly Required Delta Modules 6.4.1. Determining Relevant Delta Modules 6.4.2. Forming a Dependency Graph of Delta Modules 6.4.3. Performing a Topological Sorting of Delta Modules 6.5. Generating Variants with Versions of Variable Assets 6.6. Case Study 6.7. Demarcation from Related Work 6.8. Chapter Summary III. Realization and Application 7. Realization as Tool Suite DeltaEcore 7.1. Creating Delta Languages 7.1.1. Shared Base Metamodel 7.1.2. Common Base Delta Language 7.1.3. Delta Dialects 7.2. Specifying a Software Family with Variability in Space and Time 7.2.1. Hyper-Feature Models 7.2.2. Version-Aware Constraints 7.2.3. Delta Modules 7.2.4. Application-Order Constraints 7.2.5. Mapping Models 7.3. Deriving Variants 7.3.1. Creating a Configuration 7.3.2. Collecting Delta Modules 7.3.3. Ordering Delta Modules 7.3.4. Applying Delta Modules 8. Evaluation 8.1. Configurable TurtleBot Driver Software 8.1.1. Variability in Space 8.1.2. Variability in Time 8.1.3. Integrated Management of Variability in Space and Time 8.2. Metamodel Family for Role-Based Modeling and Programming Languages 8.2.1. Variability in Space 8.2.2. Variability in Time 8.2.3. Integrated Management of Variability in Space and Time 8.3. A Software Product Line of Feature Modeling Notations and Constraint Languages 8.3.1. Variability in Space 8.3.2. Variability in Time 8.3.3. Integrated Management of Variability in Space and Time 8.4. Results and Discussion 8.4.1. Results and Discussion of RQ1: Variability Model 8.4.2. Results and Discussion of RQ2: Variability Realization Mechanism 8.4.3. Results and Discussion of RQ3: Variant Derivation Procedure 9. Conclusion 9.1. Discussion 9.1.1. Supported Evolutionary Changes 9.1.2. Conceptual Representation of Variability in Time 9.1.3. Perception of Versions as Incremental 9.1.4. Version Numbering Schemes 9.1.5. Created Delta Languages 9.1.6. Scalability of Approach 9.2. Possible Future Application Areas 9.2.1. Extend to Full Software Ecosystem Feature Model 9.2.2. Model Software Ecosystems 9.2.3. Extract Hyper-Feature Model Versions and Record Delta Modules 9.2.4. Introduce Metaevolution Delta Modules 9.2.5. Support Incremental Reconfiguration 9.2.6. Apply for Evolution Analysis and Planning 9.2.7. Enable Evolution of Variable Safety-Critical Systems 9.3. Contribution 9.3.1. Individual Contributions 9.3.2. Handling Updater Stereotypes IV. Appendix A. Delta Operation Generation Algorithm B. Delta Dialects B.1. Delta Dialect for Java B.2. Delta Dialect for Eclipse Projects B.3. Delta Dialect for DocBook Markup B.4. Delta Dialect for Software Fault Trees B.5. Delta Dialect for Component Fault Diagrams B.6. Delta Dialect for Checklists B.7. Delta Dialect for the Goal Structuring Notation B.8. Delta Dialect for EMF Ecore B.9. Delta Dialect for EMFText Concrete Syntax Files

Linha de produtos de software (LPS) corresponde a uma das mais bem sucedidas formas de reúso, pois permite a reutilização de requisitos e arquitetura. Embora o desenvolvimento, manutenção e evolução de uma LPS ainda possua um custo alto quando comparado ao desenvolvimento de sistemas únicos (single systems), um lucro significativo pode ser obtido com a venda de diversos produtos derivados da LPS. No projeto de uma LPS analisa-se os sistemas coletivamente, ou seja, o domínio. Geradores de aplicações são ferramentas capazes de gerar artefatos a partir de uma especificação, e no caso de se ter a especificação de um domínio, é possível gerar aplicações para esse domínio. Web services representam uma tecnologia promissora para disponibilização de serviços na Web e desenvolvimento de software com arquitetura flexível e de fácil manutenção. Neste trabalho é proposta uma abordagem de desenvolvimento de linha de produtos com arquitetura orientada a serviços, na qual a geração de produtos é apoiada por um gerador de aplicações. A abordagem chama-se SoProL-WS e possui o objetivo de reduzir os custos e prazos de desenvolvimento da LPS e facilitar a sua manutenção, evolução e derivação de seus membros. SoProLWS apresenta as atividades e artefatos necessários para partir dos requisitos da LPS, projetar, implementar, configurar um gerador de aplicações e gerar seus membros a partir do gerador ou por meio de uma configuração manual. Além disso, é apresentado um estudo de caso com o desenvolvimento de uma linha de produtos de leilões Web seguindo os passos da abordagem, bem como são discutidas as alternativas de projeto relevantes para esse tipo de desenvolvimento / Software product lines (SPL) is a successful reuse technique that fosters requirements and architecture reuse. Although SPL costs with development, maintenance and evolution increases when compared to single system development, significant profit can be obtained by selling many products derived from SPL. In a SPL project, systems are analised collectively like a domain. Application generators are tools capable of generating artifacts based on an specification, in case of a domain specification, it is possible to generate applications in this domain. Web services represent a technology to make services available over a network and to develop a flexible and adaptable software architecture. This work presents an approach, called SoProL-WS, to develop SPL using service oriented architecture, where product derivation is supported by an applicator generator. The aim of this approach is to enhance flexibility, reuse and consequently decrease SPL development costs. In addition, this work presents a case study where SoProL-WS is applied to develop a Web auctions SPL

Denna uppsats tar sin utgångspunkt i att den tekniska utvecklingen påverkar hur krig genomförs idag, där strid på operativ nivå utövas med sensor- och vapensystem från någon form av plattform. Därmed kommer teknik i högre grad påverka utgången av militära operationer. Vilket gör att det är viktigt att förstå hur militärteknik påverkar operationskonst. Då operativ planering kan ses som operationalisering av operationskonst torde militär-tekniska perspektiv återfinnas i planeringsmetodbeskrivningar. För att påvisa det kausala sambandet mellan operationskonst och militärteknik formulerades hypotesen – Militärteknik omhändertas i operativ planering genom att utgöra perspektiv på operationskonstens beståndsdelar. Denna hypotes prövades sedan gentemot två svenska planeringsmetoder, utan att kunna förkastas. Därmed är hypotesen tills vidare verifierad. Även om hypotesen prövats på svenska planeringsmetoder finns det stöd för att hypotesen även är giltig för andra planeringsmetoder. Faktum är att det snarare är detaljeringsgraden på metodbeskrivningarna som avgör om hypotesens indikatorer kan återfinnas. Då operations-konst kan vara både vetenskap och konst, räcker det inte med en tydlig metodbeskrivning. Chefer och planerare måste själva omsätta underlaget till en faktisk plan. Därför är det viktigt att dessa har kunskap och vetskap om hur de ska tänka. Vilket gör att militärteknik måste vara en naturlig del av utbildningen när operationskonstens beståndsdelar diskuteras.

Linha de produtos de software (LPS) corresponde a uma das mais bem sucedidas formas de reúso, pois permite a reutilização de requisitos e arquitetura. Embora o desenvolvimento, manutenção e evolução de uma LPS ainda possua um custo alto quando comparado ao desenvolvimento de sistemas únicos (single systems), um lucro significativo pode ser obtido com a venda de diversos produtos derivados da LPS. No projeto de uma LPS analisa-se os sistemas coletivamente, ou seja, o domínio. Geradores de aplicações são ferramentas capazes de gerar artefatos a partir de uma especificação, e no caso de se ter a especificação de um domínio, é possível gerar aplicações para esse domínio. Web services representam uma tecnologia promissora para disponibilização de serviços na Web e desenvolvimento de software com arquitetura flexível e de fácil manutenção. Neste trabalho é proposta uma abordagem de desenvolvimento de linha de produtos com arquitetura orientada a serviços, na qual a geração de produtos é apoiada por um gerador de aplicações. A abordagem chama-se SoProL-WS e possui o objetivo de reduzir os custos e prazos de desenvolvimento da LPS e facilitar a sua manutenção, evolução e derivação de seus membros. SoProLWS apresenta as atividades e artefatos necessários para partir dos requisitos da LPS, projetar, implementar, configurar um gerador de aplicações e gerar seus membros a partir do gerador ou por meio de uma configuração manual. Além disso, é apresentado um estudo de caso com o desenvolvimento de uma linha de produtos de leilões Web seguindo os passos da abordagem, bem como são discutidas as alternativas de projeto relevantes para esse tipo de desenvolvimento / Software product lines (SPL) is a successful reuse technique that fosters requirements and architecture reuse. Although SPL costs with development, maintenance and evolution increases when compared to single system development, significant profit can be obtained by selling many products derived from SPL. In a SPL project, systems are analised collectively like a domain. Application generators are tools capable of generating artifacts based on an specification, in case of a domain specification, it is possible to generate applications in this domain. Web services represent a technology to make services available over a network and to develop a flexible and adaptable software architecture. This work presents an approach, called SoProL-WS, to develop SPL using service oriented architecture, where product derivation is supported by an applicator generator. The aim of this approach is to enhance flexibility, reuse and consequently decrease SPL development costs. In addition, this work presents a case study where SoProL-WS is applied to develop a Web auctions SPL

Noise pollution from aircraft is an ever-increasing issue in urban areas. Venting exhaust over body panels could reduce perceived sound pressure levels (SPL) by absorption or redirection. This paper investigates the farield spectra and sound propagation of a flat panel held near an axis-symmetric supersonic jet. In contrast to typical radial acquisition, Overall sound pressure level (OASPL) contours are constructed from a 9 by 23 cartesian acquisition gird, spaced equidistantly at 3.67 Jet Diameters (Dj). Three panel configurations each at three nozzle pressure ratios (NPR) are discussed. Additionally, a source finding algorithm is developed and shows source locations by frequency. Panel presence for nozzle design conditions result in a near flat increase in SPL across the acquired spectrum, while over and under expanded nozzle cases show the propagation of resonant modes.

The focus of this thesis was to use active noise control (ANC) to globally minimize the tonal and broadband noise radiating from a diesel generator enclosure. The major goal of this research was to show that minimizing the noise within the enclosure can lead to an overall sound pressure level (SPL) reduction of radiated noise. The target levels for overall SPL reduction were at least 2 dBA. The control algorithms used in this research were based on a filtered-x LMS adaptive algorithm, which minimizes energy density (ED). Both feedforward and feedback control approaches were investigated. The noise spectrum produced by the diesel generator enclosure includes tonal and broadband components. The target range for control was from 0 to 300 Hz. Tonal frequencies at exterior locations were often reduced by 20 to 30 dB using feedforward control. With feedback control, tones were reduced 5 to 10 dB. Broadband control results were obtained at an exterior location using a feedforward control configuration. This control was achieved for frequencies between 100 and 600 Hz and levels were reduced by up to 5 dB. Some broadband control was achieved using feedback control, but this was limited to regions at the error sensor. An overall SPL reduction of 1.9 dBA outside the enclosure was achieved near the power terminal side of the enclosure. This was accomplished using tonal and broadband feedforward control. Experimental results show that control source placement, as well as error and reference sensor location, is key to global noise reduction.

With a growing interest in technical specifications among consumers, there is a need for accessible measurement tools that enable individuals to evaluate the performance of their equipment, including common speakers and car audio systems, beyond what the manufacturer provides. However, the existing measurement systems are often geared towards professionals. This thesis aims to address this gap by designing and developing a user-friendly measurement tool that empowers individuals to easily measure and evaluate the performance of their devices. The work started with identifying the key technical specifications that users are interested in, and three parameters were selected for estimation: the maximum sound pressure level the system can provide, the corresponding multi-tone distortion and total harmonic distortion. Each parameter's measurement method varies, particularly in the choice of test stimuli and data processing. The methods in this thesis were determined after comparing existing standards for acoustical output-based measurement. Furthermore, some problems in terms of measurement capabilities and accuracy when implementing measurements within the defined application scenarios were also discussed. Ideally, the tool can finally provide users with detailed insights into chosen technical specifications, allowing them to know their audio systems better and make informed decisions. The automatic control of playback and recording as well as the processing afterwards was implemented in Python with the help of some existing packages. A graphic user interface based on PyQt was also developed to improve the manipulation of the measurement. Thus, the functionality that the tool is supposed to have is initially fulfilled, although its accuracy needs further verifying and improvement and the scope of the tool can be extended. / Med ett växande intresse för tekniska specifikationer bland konsumenter finns det ett behov av tillgängliga mätverktyg som gör det möjligt för privatpersoner att utvärdera prestandan hos sin utrustning, inklusive vanliga högtalare och bilstereosystem, utöver vad tillverkaren tillhandahåller. De befintliga mätsystemen är dock ofta inriktade på professionella användare. Denna avhandling syftar till att åtgärda denna brist genom att utforma och utveckla ett användarvänligt mätverktyg som gör det möjligt för privatpersoner att enkelt mäta och utvärdera prestandan hos sina enheter. Arbetet inleddes med att identifiera de viktigaste tekniska specifikationerna som användarna är intresserade av, och tre parametrar valdes ut för uppskattning: den maximala ljudtrycksnivå som systemet kan ge, motsvarande multitondistorsion och total harmonisk distorsion. Mätmetoden för varje parameter varierar, särskilt när det gäller valet av teststimuli och databehandling. Metoderna i denna avhandling fastställdes efter jämförelse av befintliga standarder för akustisk effektbaserad mätning. Dessutom diskuterades vissa problem när det gäller mätkapacitet och noggrannhet vid implementering av mätningar inom de definierade tillämpningsscenarierna. I bästa fall kan verktyget slutligen ge användarna detaljerade insikter i valda tekniska specifikationer, så att de kan lära känna sina ljudsystem bättre och fatta välgrundade beslut. Den automatiska styrningen av uppspelning och inspelning samt bearbetningen i efterhand implementerades i Python med hjälp av några befintliga paket. Ett grafiskt användargränssnitt baserat på PyQt utvecklades också för att förbättra hanteringen av mätningen. Den funktionalitet som verktyget är tänkt att ha är således initialt uppfylld, även om dess noggrannhet behöver verifieras och förbättras ytterligare och verktygets omfattning kan utökas.