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Empirical software engineering experts on the use of students and professionals in experiments
(2018)
Using students as participants remains a valid simplification of reality needed in laboratory contexts. It is an effective way to advance software engineering theories and technologies but, like any other aspect of study settings, should be carefully considered during the design, execution, interpretation, and reporting of an experiment. The key is to understand which developer population portion is being represented by the participants in an experiment. Thus, a proposal for describing experimental participants is put forward.
Radiofrequency ablation is an ablation technique to treat tumors with focused heat. Computer tomography, ultrasound and magnetic resonance imaging (MRI) are imaging modalities which can be used for image-guided procedures. MRI offers several advantages in comparison to the other imaging modalities, such as radiation-free fluoroscopic imaging, temperature mapping, a high-soft-tissue contrast and free selection of imaging planes. This work addresses the application of 3Dcontrollers for controlling interventional, fluoroscopic MR sequences at the scenario of MR guided radiofrequency ablation of hepatic malignancies. During this procedure, the interventionalist can monitor the targeting of the tumor with near-real time fluoroscopic sequences. In general, adjustments of the imaging planes are necessary during tumor targeting, which is performed by an assistant in the control room. Therefore, communication between the interventionalist in the scanner room and the assistant in the control room is essential. However, verbal communication is impaired due to the loud scanning noises. Alternatively, non-verbal communication between the two persons is possible, however limited to a few gestures and susceptible to misunderstandings. This work is analyzing different 3D-controllers to enable control of interventional MR sequences during MR-guided procedures directly by the interventionalist. Leap Motion, Wii Remote, SpaceNavigator, Phantom Omni and Foot Switch were selected. For that a simulation was built in C++ with VTK to feign the real scenario for test purposes. Previous results showed that Leap Motion is not suitable for the application while Wii Remote and Foot Switch are possible input devices. Final evaluation showed a generally time reduction with the use of 3D-controllers. Best results were reached with Wii Remote in 34 seconds. Handholding input devices like Wii Remote have further potential to integrate them in real environment to reduce intervention time.
Perceptual integration of kinematic components in the recognition of emotional facial expressions
(2018)
According to a long-standing hypothesis in motor control, complex body motion is organized in terms of movement primitives, reducing massively the dimensionality of the underlying control problems. For body movements, this low dimensional organization has been convincingly demonstrated by the learning of low-dimensional representations from kinematic and EMG data. In contrast, the effective dimensionality of dynamic facial expressions is unknown, and dominant analysis approaches have been based on heuristically defined facial ‘‘action units,’’ which reflect contributions of individual face muscles. We determined the effective dimensionality of dynamic facial expressions by learning of a low dimensional model from 11 facial expressions. We found an amazingly low dimensionality with only two movement primitives being sufficient to simulate these dynamic expressions with high accuracy. This low dimensionality is confirmed statistically, by Bayesian model comparison of models with different numbers of primitives, and by a psychophysical experiment that demonstrates that expressions, simulated with only two primitives, are indistinguishable from natural ones.
In addition, we find statistically optimal integration of the emotion information specified by these primitives in visual perception. Taken together, our results indicate that facial expressions might be controlled by a very small number of independent control units, permitting very low dimensional parametrization of the associated facial expression.
Workshops and tutorials
(2018)
The 19th International Conference on Product-Focused Software Process Improvement (PROFES 2018) hosted two workshops and three tutorials. The workshops and tutorials complemented and enhanced the main conference program, offering a wider knowledge perspective around the conference topics. The topics of the two workshops were Hybrid Development Approaches in Software Systems Development (HELENA) and Managing Quality in Agile & Rapid Software Development Processes (QUaSD). The topics of the tutorials were The human factor in agile transitions – using the personas concept in agile oaching, Process Management 4.0 – Best Practices, and Domain-specific languages for specification, development, and testing of autonomous systems.
Lots of movies are produced every year, too many to watch all of them and in particular, to get an overview about the evolution of typical movie genres and actors playing in them. Moreover, it is a challenging problem to detect correlations among the movies and the actors in those movies, in particular, if we are interested in time-varying data patterns like trends, countertrends, or anomalies and outliers. Those correlations are specifically interesting if they can be inspected on different levels of granularity, e.g., temporal, but also hierarchical in form of country- or continent-based correlations. In this paper we describe the IMDb Explorer, a webbased visualization tool that consists of two major views denoted by the movie cosmos and the career lines. Both views are linked and interactively manipulable while a list of user-defined metrics are explorable. We illustrate the usefulness of the visualization tool by applying it to the entire movie database provided by IMDb.
Este trabajo se enmarca dentro del vasto contexto de Ciudades Inteligentes, y se centra en el área de la conducción inteligente de vehículos, tanto en zonas urbanas como interurbanas, mediante la recogida de datos en tiempo real, medidos con sensores, por parte de los propios conductores, así como de datos capturados mediante simulación.
El objetivo de este trabajo es doble. Por un lado, el estudio y aplicación de las diferentes técnicas y métodos de detección de valores atípicos en bases de datos multivariantes, además de una comparativa entre ellos mediante las pruebas llevadas a cabo con datos de tráfico real. Y por otro lado, establecer una relación entre las situaciones anómalas de tráfico, como puedan ser atascos o accidentes, con los valores atípicos multivariantes encontrados.
La detección de valores atípicos representa una de las tareas más importantes a la hora de realizar cualquier análisis de datos, sea cual sea el dominio o área de estudio, ya que entre sus funciones primordiales se encuentra el descubrir información útil, que resulta de gran valor, y que por lo general queda oculta por la alta dimensión de los datos.
Con el uso de mecanismos de detección de valores atípicos junto con métodos de clasificación supervisada, se va a poder llevar a cabo el reconocimiento de elementos de la infraestructura vial urbana como pueden ser rotondas, pasos de cebra, cruces o semáforos.
Digital transformation has changed corporate reality and, with that, firms’ IT environments and IT governance (ITG). As such, the perspective of ITG has shifted from the design of a relatively stable, closed and controllable system of a self-sufficient enterprise to a relatively fluid, open, agile and transformational system of networked co adaptive entities. Related to this paradigm shift in ITG, this paper aims to clarify how the concept of an effective ITG framework has changed in terms of the demand for agility in organizations. Thus, this study conducted 33 qualitative interviews with executives and senior managers from the banking industry in Germany, Switzerland and Austria. Analysis of the interviews focused on the formation of categories and the assignment of individual text parts (codings) to these categories to allow for a quantitative evaluation of the codings per category. Regarding traditional and agile ITG dimensions, 22 traditional and 25 agile dimensions were identified. Moreover, agile strategies within the agile ITG construct and ten ITG patterns were identified from the interview data. The data show relevant perspectives on the implementation of traditional and new ITG dimensions and highlight ambidextrous aspects in ITG frameworks.
Die für Deutschland verfügbaren Studien zur Digitalen Transformation in klein- und mittelständischen Unternehmen (KMU) sind sich weitgehend einig. KMU tun sich mit dem Thema Digitalisierung schwer. Der vorliegende Beitrag diskutiert, weshalb KMU an der Digitalen Transformation scheitern und was dagegen getan werden kann.
Digital transformation has changed corporate reality and, with that, firms’ IT environments and IT governance (ITG). As such, the perspective of ITG has shifted from the design of a relatively stable, closed and controllable System of a self-sufficient Enterprise to a relatively fluid, open, agile and transformational system of networked co-adaptive entities. Related to this paradigm shift in ITG, this paper aims to clarify how the concept of an effective ITG framework has changed in terms of the demand for agility in organizations. Thus, this study conducted 33 qualitative interviews with executives and senior managers from the banking industry in Germany, Switzerland and Austria. Analysis of the interviews focused on the formation of categories and the assignment of individual text parts (codings)
to these categories to allow for a quantitative evaluation of the codings per category. Regarding traditional and agile ITG dimensions, 22 traditional and 25 agile dimensions in terms of structures, processes and relational mechanisms were identified. Moreover, agile strategies within the agile ITG construct and ten ITG patterns were identified from the interview data. The data show relevant perspectives on the implementation of traditional and new ITG dimensions and highlight ambidextrous aspects in ITG in the German-speaking banking industry.
Active storage
(2018)
In brief, Active Storage refers to an architectural hardware and software paradigm, based on collocation storage and compute units. Ideally, it will allow to execute application-defined data ... within the physical data storage. Thus Active Storage seeks to minimize expensive data movement, improving performance, scalability, and resource efficiency. The effective use of Active Storage mandates new architectures, algorithms, interfaces, and development toolchains.
A transaction is a demarcated sequence of application operations, for which the following properties are guaranteed by the underlying transaction processing system (TPS): atomicity, consistency, isolation, and durability (ACID). Transactions are therefore a general abstraction, provided by TPS that simplifies application development by relieving transactional applications from the burden of concurrency and failure handling. Apart from the ACID properties, a TPS must guarantee high and robust performance (high transactional throughput and low response times), high reliability (no data loss, ability to recover last consistent state, fault tolerance), and high availability (infrequent outages, short recovery times).
The architectures and workhorse algorithms of a high-performance TPS are built around the properties of the underlying hardware. The introduction of nonvolatile memories (NVM) as novel storage technology opens an entire new problem space, with the need to revise aspects such as the virtual memory hierarchy, storage management and data placement, access paths, and indexing. NVM are also referred to as storage-class memory (SCM).
The focus of the developed maturity model was set on processes. The concept of the widespread CMM and its practices has been transferred to the perioperative domain and the concept of the new maturity model. Additional optimization goals and technological as well as networking-specific aspects enable a process- and object-focused view of the maturity model in order to ensure broad coverage of different subareas. The evaluation showed that the model is applicable to the perioperative field. Adjustments and extensions of the maturity model are future steps to improve the rating and classification of the new maturity model.
Die minimal-invasive Chirurgie (MIC) entwickelt sich durch den Einsatz von medizinischen Robotern wie dem da Vinci System von Intuitive Surgical stetig weiter. Hierdurch kann eine bessere oder gleichwertige Operation bei deutlich geringerer körperlicher Belastung des Operateurs erreicht werden. Dabei entstehen jedoch neue Problemstellungen wie beispielsweise Kollision zwischen Roboterarmen und die benötigte Zeit zum Einrichten einer geeigneten Roboterkonfiguration. Daher ist eine effiziente Vorbereitung und Planung der Interventionen erforderlich. Diese Arbeit präsentiert einen Ansatz für eine verbesserte Planung mit Augmented Reality (AR) und einer Robotik Simulationssoftware (RS). Die Robotik Simulation dient zur Berechnung einer Roboterkonfiguration unter Vorgabe der Port-Positionen. Augmented Reality wird verwendet, um die berechneten Pose in der realen Umgebung zu visualisieren und somit leichter in den Operationssaal zu übertragen.
Die Segmentierung und das Tracking von minimal-invasiven robotergeführten Instrumenten ist ein wesentlicher Bestandteil für verschiedene computer assistierte Eingriffe. Allerdings treten in der minimal-invasiven Chirurgie, die das Anwendungsfeld für den hier beschriebenen Ansatz darstellt, häufig Schwierigkeiten durch Reflexionen, Schatten oder visuelle Verdeckungen durch Rauch und Organe auf und erschweren die Segmentierung und das Tracking der Instrumente.
Dieser Beitrag stellt einen Deep Learning Ansatz für ein markerloses Tracking von minimal-invasiven Instrumenten vor und wird sowohl auf simulierten als auch realen Daten getestet. Es wird ein simulierter als auch realer Datensatz mit Ground Truth Kennzeichnung für die binäre Segmentierung von Instrument und Hintergrund erstellt. Für den simulierten Datensatz werden Bilder aus einem simulierten Instrument und realem Hintergrund zusammengesetzt. Im Falle des realen Datensatzes spricht man von der Zusammensetzung der Bilder aus einem realen Instrument und Hintergrund. Insgesamt wird auf den simulierten Daten eine Pixelgenauigkeit von 94.70 Prozent und auf den realen Daten eine Pixelgenauigkeit von 87.30 Prozent erreicht.
Being able to monitor the heart activity of patients during their daily life in a reliable, comfortable and affordable way is one main goal of the personalized medicine. Current wearable solutions lack either on the wearing comfort, the quality and type of the data provided or the price of the device. This paper shows the development of a Textile Sensor Platform (TSP) in the form of an electrocardiogram (ECG)-measuring T-shirt that is able to transmit the ECG signal to a smartphone. The development process includes the selection of the materials, the design of the textile electrodes taking into consideration their electrical characteristics and ergonomy, the integration of the electrodes on the garment and their connection with the embedded electronic part. The TSP is able to transmit a real-time streaming of the ECG-signal to an Android smartphone through Bluetooth Low Energy (BLE). Initial results show a good electrical quality in the textile electrodes and promising results in the capture and transmission of the ECG signal. This is still a working- progress and it is the result of an interdisciplinary master project between the School of Informatics and the School of Textiles & Design of the Reutlingen University.
This work is a report on practical experiences with the issue of interoperability in German practice management systems (PMSs) from an ongoing clinical trial on teledermatology, the TeleDerm project. A proprietary and established web-platform for store-and-forward telemedicine is integrated with the IT in the GPs’ offices for automatic exchange of basic patient data. Most of the 19 different PMSs included in the study sample lack support of modern health data exchange standards, therefore the relatively old but widely available German health data exchange interface “Gerätedatentransfer” (GDT) is used. Due to the lack of enforcement and regulation of the GDT standard, several obstacles to interoperability are encountered. As a partial, but reusable working solution to cope with these issues, we present a custom middleware which is used in conjunction with GDT. We describe the design, technical implementation and observed hindrances with the existing infrastructure. A discussion on health care interfacing standards and the current state of interoperability in German PMS software is given.
We present an approach for segmenting individual cells and lamellipodia in epithelial cell clusters using fully convolutional neural networks. The method will set the basis for measuring cell cluster dynamics and expansion to improve the investigation of collective cell migration phenomena. The fully learning-based front-end avoids classical feature engineering, yet the network architecture needs to be designed carefully. Our network predicts how likely each pixel belongs to one of the classes and, thus, is able to segment the image. Besides characterizing segmentation performance, we discuss how the network will be further employed.
Background: Internationally, teledermatology has proven to be a viable alternative to conventional physical referrals. Travel cost and referral times are reduced while patient safety is preserved. Especially patients from rural areas benefit from this healthcare innovation. Despite these established facts and positive experiences from EU neighboring countries like the Netherlands or the United Kingdom, Germany has not yet implemented store-and-forward teledermatology in routine care.
Methods: The TeleDerm study will implement and evaluate store-and-forward teledermatology in 50 general practitioner (GP) practices as an alternative to conventional referrals. TeleDerm aims to confirm that the possibility of store-and-forward teledermatology in GP practices is going to lead to a 15% (n = 260) reduction in referrals in the intervention arm. The study uses a cluster-randomized controlled trial design. Randomization is planned for the cluster “county”. The main observational unit is the GP practice. Poisson distribution of referrals is assumed. The evaluation of secondary outcomes like acceptance, enablers and barriers uses a mixed methods design with questionnaires and interviews.
Discussion: Due to the heterogeneity of GP practice organization, patient management software, information technology service providers, GP personal technical affinity and training, we expect several challenges in implementing teledermatology in German GP routine care. Therefore, we plan to recruit 30% more GPs than required by the power calculation. The implementation design and accompanying evaluation is expected to deliver vital insights into the specifics of implementing telemedicine in German routine care.
Modern persistent Key/Value stores are designed to meet the demand for high transactional throughput and high data ingestion rates. Still, they rely on backwards-compatible storage stack and abstractions to ease space management, foster seamless proliferation and system integration. Their dependence on the traditional I/O stack has negative impact on performance, causes unacceptably high write-amplification, and limits the storage longevity.
In the present paper we present NoFTL KV, an approach that results in a lean I/O stack, integrating physical storage management natively in the Key/Value store. NoFTL-KV eliminates backwards compatibility, allowing the Key/Value store to directly consume the characteristics of modern storage technologies. NoFTLKV is implemented under RocksDB. The performance evaluation under LinkBench shows that NoFTL-KV improves transactional throughput by 33%, while response times improve up to 2.3x. Furthermore, NoFTL KV reduces write-amplification 19x and improves storage longevity by imately the same factor.
Blockchains yield to new workloads in database management systems and K/V-stores. Distributed Ledger Technology (DLT) is a technique for managing transactions in ’trustless’ distributed systems. Yet, clients of nodes in blockchain networks are backed by ’trustworthy’ K/V-Stores, like LevelDB or RocksDB in Ethereum, which are based on Log-Structured Merge Trees (LSM Trees). However, LSM-Trees do not fully match the properties of blockchains and enterprise workloads.
In this paper, we claim that Partitioned B-Trees (PBT) fit the properties of this DLT: uniformly distributed hash keys, immutability, consensus, invalid blocks, unspent and off-chain transactions, reorganization and data state / version ordering in a distributed log-structure. PBT can locate records of newly inserted key-value pairs, as well as data of unspent transactions, in separate partitions in main memory. Once several blocks acquire consensus, PBTs evict a whole partition, which becomes immutable, to secondary storage. This behavior minimizes write amplification and enables a beneficial sequential write pattern on modern hardware. Furthermore, DLT implicate some type of log-based versioning. PBTs can serve as MV-store for data storage of logical blocks and indexing in multi-version concurrency control (MVCC) transaction processing.
Decentralized energy systems are characterized by an ad hoc planing. The missing integration of energy objectives into business strategy creates difficulties resulting in inefficient energy architectures and decisions. Practice-proven methods such as balanced scorecard, enterprise architecture management and value network approach supports the transformation path towards an effective decentralized system. The methods are evaluated based on a case study. Managing multi-dimensionality, high complexity and multiple actors are the main drivers for an effective and efficient energy management system. The underlying basis to gain the positive impacts of these methods on decentralized corporate energy systems is digitization of energy data and processes.
Digital enterprise architecture management in tourism : state of the art and future directions
(2018)
The advance of information technology impacts tourism more than many other industries, due to the service character of its products. Most offerings in tourism are immaterial in nature and challenging in coordination. Therefore, the alignment of IT and strategy and digitization is of crucial importance to enterprises in tourism. To cope with the resulting challenges, methods for the management of enterprise architectures are necessary. Therefore, we scrutinize approaches for managing enterprise architectures based on a literature research. We found many areas for future research on the use of enterprise architecture in tourism.
Digitization of societies changes the way we live, work, learn, communicate, and collaborate. In the age of digital transformation IT environments with a large number of rather small structures like Internet of Things (IoT), microservices, or mobility systems are emerging to support flexible and agile digitized products and services. Adaptable ecosystems with service oriented enterprise architectures are the foundation for self-optimizing, resilient run-time environments and distributed information systems. The resulting business disruptions affect almost all new information processes and systems in the context of digitization. Our aim are more flexible and agile transformations of both business and information technology domains with more flexible enterprise information systems through adaptation and evolution of digital enterprise architectures. The present research paper investigates mechanisms for decision-controlled digitization architectures for Internet of Things and microservices by evolving enterprise architecture reference models and state of the art elements for architectural engineering for micro-granular systems.
Container virtualization evolved into a key technology for deployment automation in line with the DevOps paradigm. Whereas container management systems facilitate the deployment of cloud applications by employing container based artifacts, parts of the deployment logic have been applied before to build these artifacts. Current approaches do not integrate these two deployment phases in a comprehensive manner. Limited knowledge on application software and middleware encapsulated in container-based artifacts leads to maintainability and configuration issues. Besides, the deployment of cloud applications is based on custom orchestration solutions leading to lock in problems. In this paper, we propose a two-phase deployment method based on the TOSCA standard. We present integration concepts for TOSCA-based orchestration and deployment automation using container-based artifacts. Our two-phase deployment method enables capturing and aligning all the deployment logic related to a software release leading to better maintainability. Furthermore, we build a container management system, which is composed of a TOSCA-based orchestrator on Apache Mesos, to deploy container-based cloud applications automatically.
The state of the art proposes the microservices architectural style to build applications. Additionally, container virtualization and container management systems evolved into the perfect fit for developing, deploying, and operating microservices in line with the DevOps paradigm. Container virtualization facilitates deployment by ensuring independence from the runtime environment. However, microservices store their configuration in the environment. Therefore, software developers have to wire their microservice implementation with technologies provided by the target runtime environment such as configuration stores and service registries. These technological dependencies counteract the portability benefit of using container virtualization. In this paper, we present AUTOGENIC - a model-based approach to assist software developers in building microservices as self configuring containers without being bound to operational technologies. We provide developers with a simple configuration model to specify configuration operations of containers and automatically generate a self-configuring microservice tailored for the targeted runtime environment. Our approach is supported by a method, which describes the steps to automate the generation of self-configuring microservices. Additionally, we present and evaluate a prototype, which leverages the emerging TOSCA standard.
Engineers of the research project “Digital Product Life-Cycle” are using a graph-based design language to model all aspects of the product they are working on. This abstract model is the base for all further investigations, developments and implementations. In particular at early stages of development, collaborative decision making is very important. We propose a semantic augmented knowledge space by means of mixed reality technology, to support engineering teams. Therefore we present an interaction prototype consisting of a pico projector and a camera. In our usage scenario engineers are augmenting different artefacts in a virtual working environment. The concept of our prototype contains both an interaction and a technical concept. To realise implicit and natural interactions, we conducted two prototype tests: (1) A test with a low-fidelity prototype and (2) a test by using the method Wizard of Oz. As a result, we present a prototype with interaction selection using augmentation spotlighting and an interaction zoom as a semantic zoom.
Der Siegeszug von Social Media im privaten Umfeld hat die Vorteile dieser Kommunikationswerkzeuge aufgezeigt. Unternehmen versuchen, diese Erfolge für sich zu nutzen und setzen Social Media für ihre Kommunikationsaktivitäten ein. In der externen Kommunikation etwa ermöglichen diese Werkzeuge einen schnellen und unkomplizierten Nachrichtenaustausch mit Kunden oder helfen Kundenexpertise in organisationale Prozesse, etwa Produktentwicklung oder Kundenbeschwerdemanagement, zu integrieren. Auch in der internen Kommunikation entstehen durch den Einsatz von Social Media neue Kanäle. Eine spezielle Gruppe von Social-Media Werkzeugen für die interne Kommunikation und Kollaboration wird als Enterprise Social Networks (ESN) bezeichnet.
Purpose: This study aims to conceptualize and test the effect of consumers´ perceptions of complaint handling quality (PCHQ) in both traditional and social media channels.
Design/methodology/approach: Study 1 systematically reviews the relevant literature and then carries out a consumer and manager survey. This approach aims to conceptualize the dimensionality of PCHQ. Study 2 tests the effect of PCHQ on key marketing outcomes. Using survey data from a German telecommunications company, the study provides an explanation for the differences in outcomes across traditional (hotline) and social media channels.
Findings: Study 1 reveals that PCHQ is best conceptualized as a five dimensional construct with 15 facets. There are significant differences between customers and managers in terms of the importance attached to the various dimensions. The construct shows strong psychometric properties with high reliability and validity, thereby opening up opportunities to treat these facets as measurement indicators for the construct. Study 2 indicates that the effect of PCHQ on consumer loyalty and word-of-mouth (WOM) communication is stronger in social media than in traditional channels. Procedural justice and the overall quality of service solutions emerge as general dimensions of PCHQ because they are equally important in both channels. In contrast, interactional justice, distributive justice and customer effort have varying effects across the two channels.
Research limitations/implications: This study contributes to the understanding of a firm´s channel selection for complaint handling in two ways. First, it evaluates and conceptualizes the PCHQ construct. Second, it compares the effects of different dimensions of PCHQ on key marketing outcomes across traditional and socialmedia channels.
Practical implications: This study enables managers to understand the difference in efficacy attached to different dimensions of PCHQ. It further highlights such differences across traditional and social media service channels. For example, the effect of complaint handling on social media is of particular importance when generating WOM communication.
Originality/value: This study offers a comprehensive conceptualization of the PCHQ construct and reveals the general and channel contingent effects of its different dimensions on key marketing outcomes.
Motor-based theories of facial expression recognition propose that the visual perception of facial expression is aided by sensorimotor processes that are also used for the production of the same expression. Accordingly, sensorimotor and visual processes should provide congruent emotional information about a facial expression. Here, we report evidence that challenges this view. Specifically, the repeated execution of facial expressions has the opposite effect on the recognition of a subsequent facial expression than the repeated viewing of facial expressions. Moreover, the findings of the motor condition, but not of the visual condition, were correlated with a nonsensory condition in which participants imagined an emotional situation. These results can be well accounted for by the idea that facial expression recognition is not always mediated by motor processes but can also be recognized on visual information alone.
The blockchain technology enables a common data basis between the participants. Entries are logged and the authenticity of the participants is guaranteed. In the case of a relationship between customers and producers, this would lead to verifiable cooperation, which would be a major step as companies enter into service contracts based on the flow of many small transactions through communication. This paper proposes an architecture that enables the creation and processing of orders between the customer and producers via a blockchain based production network. The handling of larger files which are traceable via the blockchain is also shown and the use of a public or permissioned blockchain for an application case is also considered.
The use of additive manufacturing technologies for industrial production is constantly growing. This technology differs from the known production proecdures. The areas for scheduling, detailed and sequence planning are particularly important for additive production due to the long print times and flexible use of the production area. Therefore, production-relevant variables are considered and used for the production planning and control (PPC) of additive manufacturing machines. For this purpose, an optimization model is presented which shows a time-oriented build space utilization. In the implementation, a nesting algorithm is used to check the combinability of different models for each individual print job.
The relative pros and cons of using students or practitioners in experiments in empirical software engineering have been discussed for a long time and continue to be an important topic. Following the recent publication of “Empirical software engineering experts on the use of students and professionals in experiments” by Falessi, Juristo, Wohlin, Turhan, Münch, Jedlitschka, and Oivo (EMSE, February 2018) we received a commentary by Sjøberg and Bergersen. Given that the topic is of great methodological interest to the community and requires nuanced treatment, we invited two editorial board members, Martin Shepperd and Per Runeson, respectively, to provide additional views.
Back to the future: origins and directions of the “Agile Manifesto” – views of the originators
(2018)
In 2001, seventeen professionals set up the manifesto for agile software development. They wanted to define values and basic principles for better software development. On top of brought into focus, the manifesto has been widely adopted by developers, in software-developing organizations and outside the world of IT. Agile principles and their implementation in practice have paved the way for radical new and innovative ways of software and product development. In parallel, the understanding of the manifesto’s underlying principles evolved over time. This, in turn, may affect current and future applications of agile principles. This article presents results from a survey and an interview study in collaboration with the original contributors of the manifesto for agile software development. Furthermore, it comprises the results from a workshop with one of the original authors. This publication focuses on the origins of the manifesto, the contributors’ views from today’s perspective, and their outlook on future directions. We evaluated 11 responses from the survey and 14 interviews to understand the viewpoint of the contributors. They emphasize that agile methods need to be carefully selected and agile should not be seen as a silver bullet. They underline the importance of considering the variety of different practices and methods that had an influence on the manifesto. Furthermore, they mention that people should question their current understanding of "agile" and recommend reconsidering the core ideas of the manifesto.
Software and system development faces numerous challenges of rapidly changing markets. To address such challenges, companies and projects design and adopt specific development approaches by combining well-structured methods and flexible agile practices. Yet, the number of methods and practices is large and the actual process composition is often carried out in an ad-hoc manner. This paper reports on a survey on hybrid software development approaches. We study which approaches are used in practice, how different approaches are combined, and what contextual factors influence the use and combination of hybrid software development approaches.
Software engineering education is supposed to provide students with industry-relevant knowledge and skills. Educators must address issues beyond exercises and theories that can be directly rehearsed in small settings. A way to experience such effects and to increase the relevance of software engineering education is to apply empirical studies in teaching. In our article, we show how different types of empirical studies can be used for educational purposes in software engineering. We give examples illustrating how to utilize empirical studies, discuss challenges, and derive an initial guideline that supports teachers to include empirical studies in software engineering courses.
The need for creating digitally enhanced products, services, and experiences as well as the emergence of new or modified business models has a significant impact on the automotive domain. Innovative solutions and new topics such as Smart Mobility or Connectivity require current automotive development processes to undergo major changes. They need to be redesigned in a way that it is possible to learn and adapt continuously at a fast pace. Agile methods are promising approaches to address these new challenges. However, agile methods are not tailored to the specific characteristics of the automotive domain such as software product line (SPLs) development. Although, there have been efforts to apply agile methods in the automotive domain, widespread adoptions have not yet taken place.
Software engineering courses have to deliver theoretical and technical knowledge and skills while establishing links to practice. However, due to course goals or resource limitations, it is not always possible or even meaningful to set up complete projects and let students work on a real piece of software. For instance, if students shall understand the impact of group dynamics on productivity, a particular software to be developed is of less interest than an environment in which students can learn about team-related phenomena. To address this issue, we use experimentation as a teaching tool in software engineering courses. Experiments help to precisely characterize and study a problem in a systematic way, to observe phenomena, and to develop and evaluate solutions. Furthermore, experiments help establishing short feedback and learning cycles, and they also allow for experiencing risk and failure scenarios in a controlled environment. In this paper, we report on three courses in which we implemented different experiments and we share our experiences and lessons learned. Using these courses, we demonstrate how to use classroom experiments, and we provide a discussion on the feasibility based on formal and informal course evaluations. This experience report thus aims to help teachers integrating small- and medium sized experiments in their courses.
An assessment model to foster the adoption of agile software product lines in the automotive domain
(2018)
A software product line is commonly used for the software development in large automotive organizations. A strategic reuse of software is needed to handle the increasing complexity of the development and to maintain the quality of numerous software variants. However, the development process needs to be continuously adapted at a fast pace to satisfy the changing market demands. Introducing agile software development methods promise the flexibility to react on customers’ change requests and market demands to deliver high quality software. Despite this need, it is still challenging to combine agile software development and product lines. The maturity of an agile adoption is often hard to determine. Assessing the current situation regarding the combination is a first step towards a successful inclusion of agile methods into automotive software product lines. Based on an interview study with 16 participants and a literature review, we build the so-called ASPLA Model allowing self-assessments within the team to determine the current state of agile software development in combination with software product lines. The model comprises seven areas of improvement and recommends a possibility to improve the current status.
Combining agile development and software product lines in automotive: challenges and recommendations
(2018)
Software product lines (SPLs) are used throughout the automotive industry. SPLs help to manage the large number of variants and to improve quality by reuse. In order to develop high quality software faster, agile software development (ASD) practices are introduced. From both the research and the management point of view it is still not clear how these two approaches can be combined. We derive recommendations to combine ASD and SPLs based on challenges identified for an automotive specific model. This study combines the outcome of a literature review and a qualitative interview study with 16 practitioners from the automotive domain. We evaluate the results and analyze the relationship between ASD and SPLs in the automotive domain. Furthermore, we derive recommendations to combine ASD and SPLs based on challenges identified in the automotive domain. This study identifies 86 individual challenges. Important challenges address supplier collaboration and faster software release cycles without loss of quality. The identified challenges and the derived recommendations show that the combination of ASD and SPL in the automotive industry is promising but not trivial. There is a need for an automotive-specific approach that combines ASD and SPL.
Context: Software product lines are widely used in automotive embedded software development. This software paradigm improves the quality of software variants by reuse. The combination of agile software development practices with software product lines promises a faster delivery of high quality software. However, the set up of an agile software product line is still challenging, especially in the automotive domain. Goal: This publication aims to evaluate to what extend agility fits to automotive product line engineering. Method: Based on previous work and two workshops, agility is mapped to software product line concerns. Results: This publication presents important principles of software product lines, and examines how agile approaches fit to those principles. Additionally, the principles are related to one of the four major concerns of software product line engineering: Business, Architecture, Process, and Organization. Conclusion: Agile software product line engineering is promising and can add value to existing development approaches. The identified commonalities and hindering factors need to be considered when defining a combined agile product line engineering approach.
Context: Organizations increasingly develop software in a distributed manner. The cloud provides an environment to create and maintain software-based products and services. Currently, it is unknown which software processes are suited for cloud-based development and what their effects in specific contexts are.
Objective: We aim at better understanding the software process applied to distributed software development using the cloud as development environment. We further aim at providing an instrument which helps project managers comparing different solution approaches and to adapt team processes to improve future project activities and outcomes.
Method: We provide a simulation model which helps analyzing different project parameters and their impact on projects performed in the cloud. To evaluate the simulation model, we conduct different analyses using a Scrumban process and data from a project executed in Finland and Spain. An extra adaptation of the simulation model for Scrum and Kanban was used to evaluate the suitability of the simulation model to cover further process models.
Results: A comparison of the real project data with the results obtaind from the different simulation runs shows the simulation producing results close to the real data, and we could successfully replicate a distributed software project. Furthermore, we could show that the simulation model is suitable to address further process models.
Conclusion: The simulator helps reproducing activities, developers, and events in the project, and it helps analyzing potential tradeoffs, e.g., regarding throughput, total time, project size, team size and work-in-progress limits. Furthermore, the simulation model supports project managers selecting the most suitable planning alternative thus supporting decision-making processes.
Free-floating e-scooter sharing is an upcoming trend in mobility, which has been spreading since 2015 in various German cities. Unlike the more scientifically explorend car sharing, the usage patterns and behaviors of e-scooter sharing customers are yet to be analyzed. This presumably discovers better ways to attract customers as well as adaptions of the business model in order to increase scooter utilization and therefore the profit of the e-scooter providers. As most of the customer's journey, from registration to scooter reservation and the ride itself, is digitally traceable, large datasets are available allowing for understanding of customers' needs and motivations. Based on these datasets of an e-scooter provider operating in a big German city we propose a customer clustering that identifies four different customer segments, which enables multiple conclusions to be drawn for business development and improving the problem-solution fit of the e-scooter sharing model.
With the digital transformation being one of the most discussed topics in the business world today, many enterprises – especially small and medium sized ones – find themselves struggling with the understanding of new digital technologies and thus the potential benefits and risks for their companies. New technologies like the Internet of Things, Blockchain or Machine Learning have great potential for businesses. However, carefully evaluating and selecting purposeful technologies – aligned to the digital strategy – is the key to success. Technologies appear, change and also vanish so rapidly in the digital age, that a proper understanding is crucial for a sustainable technological foundation. Focusing on the characteristic features of technologies, the presented approach promises to create a better technological understanding for decision makers in small and medium-sized enterprises (SMEs) in a playful manner: With a serious game that fosters insight and allays fears of digitalization.
Unternehmen stehen aktuell aufgrund der Digitalisierung, des stetigen technologischen Fortschritts und immer kürzer werdenden Produktlebenszyklen vor großen Herausforderungen. Um am Markt bestehen zu können, müssen Geschäftsmodelle öfter und schneller an sich verändernde Marktverhältnisse angepasst werden als dies früher der Fall war. Eine schnelle Anpassungsfähigkeit, auch Agilität genannt, ist in der heutigen Zeit ein entscheidender Wettbewerbsfaktor. Aufgrund des stetig wachsenden IT Anteils in Produkten sowie der Tatsache, dass diese IT-gestützt hergestellt werden, haben Änderungen des Geschäftsmodells große Auswirkungen auf die Unternehmensarchitektur eines Unternehmens.
Eine Unternehmensarchitektur umspannt das Unternehmen, indem diese die fachlichen und technischen Strukturen, insbesondere die gesamte IT, des Unternehmens beinhaltet und integriert. Das Management der Unternehmensarchitektur ist die Disziplin zur Beherrschung und Abstimmung dieser Strukturen. An der Gestaltung der Unternehmensarchitektur wirken viele Stakeholder mit individuellen und teils gegensätzlichen Interessen aus den unterschiedlichsten Bereichen des Unternehmens mit. Dies macht die Entscheidungsfindung zu einer komplexen Aufgabe.
Die in dieser Arbeit entworfene integrative Methode für die Entscheidungsfindung hat das Ziel, die Betroffenen und Beteiligten, im Folgenden Stakeholder, bei ihren Entscheidungen zu unterstützen. Die Grundidee hierbei ist die systematische Einbeziehung der Interessen der Stakeholder und davon abgeleiteter Visualisierungen. Dies verleiht der Methode ihren integrativen Charakter und hilft Abhängigkeiten zwischen Stakeholdern zu erkennen. Dadurch wird die Zusammenarbeit zwischen den an Entscheidungen beteiligten Stakeholdern gefördert. Neben der systematischen Einbeziehung von Visualisierungen wird im Rahmen dieser Arbeit das Konzept der Technik eingeführt. Techniken werden ebenfalls von den Interessen der Stakeholder abgeleitet und dienen der Unterstützung bei der Durchführung von Aktivitäten der Entscheidungsfindung, indem Vorgehensweisen bei bestimmten Aufgaben vorgegeben oder Teilprozesse der Entscheidungsfindung sogar automatisiert durchgeführt werden. Das Konzept der Technik, die systematische Ableitung von den Interessen der Stakeholder sowie das Zusammenspiel mit Visualisierungen wird in dieser Arbeit in Form einer erweiterten Konzeptualisierung der Architekturbeschreibung definiert.
Da die Werkzeugunterstützung in der Praxis häufig eine Herausforderung darstellt, rundet diese Arbeit ein eigens konzipiertes und prototypisch validiertes Architekturcockpit ab. Das Cockpit ist eine auf einem elektronischen Sitzungsraum basierende Werkzeugunterstützung der eingeführten integrativen Methode.
This research addresses the question of why employees use enterprise social networks (ESN). Against the background of technology acceptance research, we propose an extended unified theory of acceptance and use of technology (UTAUT) model, adapt it to an ESN context, and test our model against data from ESN users of large and medium-sized enterprises. We use partial least squares structural equation modeling to gain insights into the determinants of ESN use. This paper contributes to ESN acceptance research by evaluating a model containing determinants of ESN use. It also examines the effects of determinants on five different usage dimensions of ESN. The results reveal that facilitating conditions are the main driver of ESN use while the impact of intention to use is comparably small. Implications for theory and practice are discussed.
The very first International Workshop on Software-intensive Business: Start-ups, Ecosystems and Platforms (SiBW 2018) was held in Espoo (Greater Helsinki), Finland on December 3rd, 2018 – just a day before SLUSH 2018, the world’s biggest startup event. Thanks to the collaboration with the organizers of SLUSH, many of the software-intensive business researchers and practitioners took part also in this event.
The international workshop gathered together 35 registered attendees, from Sweden, Germany, Latvia, Finland, Italy and the Netherlands representing both academia as well as industry. The event itself was sponsored by VTT Technical Research Centre of Finland and the workshop was organized by the newly founded Software-intensive Business research community together with Software Startup Research Network (SSRN).
Enterprise Governance, Risk and Compliance (GRC) systems are key to managing risks threatening modern enterprises from many different angles. Key constituent to GRC systems is the definition of controls that are implemented on the different layers of an Enterprise Architecture (EA). As part of the compliance aspect of GRC, the effectiveness of these controls is assessed and reported to relevant management bodies within the enterprise. In this paper we present a metamodel which links controls to the affected elements of an EA and supplies a way of expressing associated assessment techniques and results. We complement the metamodel with an expository instantiation in a cockpit for control compliance applied in an international enterprise in the insurance industry.
Digital Enterprise Architecture allows multiple viewpoints on a company’s IT landscape. To gain valuable information out of huge amounts of operational data, it is indispensable to have both an understanding of the operations architecture and an engine capable of managing Big Data. The mechanism of understanding huge amounts of data is based on three main steps: collect, process and use. The main idea is focused on extracting valuable information out of Big Data to make better design decisions. The Elastic Stack is an open-source solution to comfortably and quickly handle Big Data scenarios.