Open Access

Power consumption has become a major design constraint, especially for battery-powered embedded systems. However, the impact of software applications is typically considered in later phases, where both software and hardware parts are close to their finalization. Power-related issues must be detected in early stages to keep the development costs low, satisfy time-to-market, and avoid cost-intensive redesign loops. Moreover, the variety of hardware components, architectures, and communication interfaces make the development of embedded software more challenging. To manage the complexity of software applications, approaches such as model-driven development (MDD) may be used. This article proposes a power-estimation approach in MDD for software application models in early development phases. A unified modeling language (UML) profile is introduced to model power-related properties of hardware components. To determine the impact of software applications, we defined two analysis methods using simulation data and a novel in-the-loop concept. Both methods may be applied at different development stages to determine an energy trace, describing the energy-related behavior of the system. A novel definition of energy bugs is provided to describe power-related misbehavior. We apply our approach to a sensor node example, demonstrate an energy bug detection, and compare the runtime and accuracy of the analysis methods.

Kaum ein anderes Gebiet unterliegt solch einer Dynamik wie die Entwicklung von Beziehungsnetzwerken gerade im Internet, siehe Facebook, Twitter und Co. Es ergeben sich aber auch Chancen für die intelligente Auswertung von Beziehungsnetzwerken und Ableitung von Handlungsmustern zur Optimierung des eigenen Geschäfts. Dieser Beitrag legt dar, dass klassische Methoden des Analytical CRM keine ausreichenden Antworten zur Ableitung von Handlungsmustern bieten. Daher wurde das Konzept der " Learning Systems Method for iSCRM" entwickelt. Wirkmuster zur Selbstoptimierung werden als Handlungsmuster zur Optimierung von Beziehungsnetzwerken im SCRM spezifiziert. Es wird gezeigt, wie sich durch deren Einsatz explizite Wissensmodelle über Beziehungen und deren Akteure verbessern lassen. Schließlich wird ein Ausblick auf eine IT-technische Umsetzung auf der Basis des Web 3.0 gegeben. Durch den Einsatz der vorgestellten Methode, werden Unternehmen in die Lage versetzt, sich ergebene Chancen schnell zu erkennen und vor ihren Marktbegleitern zu verwerten.

Usability is a core construct of website evaluation and inherently defined as interactive. Yet, when analysing first impressions of websites, expected usability, i.e., before use, is of interest. Here we investigate to what extend ratings of expected usability are related to (a) experienced usability, i.e., ratings after use, and (b) objective usability measures, i.e., task performance. Furthermore, we try to elucidate how ratings of expected usability are correlated to aesthetic judgments. In an experiment, 57 participants submitted expected usability ratings after the presentation of website screenshots in three viewing-time conditions (50, 500, and 10,000 ms) and after an interactive task (experienced usability). Additionally, objective usability measures (task completion and duration) and subjective aesthetics evaluations were recorded for each website. The results at both the group and individual level show that expected usability ratings are not significantly related either to experienced usability or objective usability measures. Instead, they are highly correlated with aesthetics ratings. Taken together, our results highlight the need for interaction in empirical website usability testing, even when exploring very early usability impressions. In our study, user ratings of expected usability were no valid proxy neither for objective usability nor for experienced website usability.

Technology Informatics Guiding Education Reform (TIGER) works to advance the integration of health informatics by enabling the use of informatics and technology to improve patient care while fostering a learning health system

Due to the resource-constrained nature of embedded systems, it is crucial to support the estimation of their power consumption as early in the development process as possible. Non-functional requirements based on power consumption directly impact the software design, e.g., watt-hour thresholds and expected lifetimes based on battery capacities. Even if software affects hardware behavior directly, these types of requirements are often overlooked by software developers because they are commonly associated with the hardware layer. Modern trends in software engineering such as Model-Driven Development (MDD) can be used in embedded software development to evaluate power consumption-based requirements in early design phases. However, power consumption aspects are currently not sufficiently considered in MDD approaches. In this paper, we present a model-driven approach using Unified Modeling Language profile extensions to model hardware components and their power characteristics. Software m odels are combined with hardware models to achieve a system-wide estimation, including peripheral devices, and to make the power-related impact in early design stages visible. By deriving energy profiles, we provide software developers with valuable feedback, which may be used to identify energy bugs and evaluate power consumption-related requirements. To demonstrate the potential of our approach, we use a sensor node example to evaluate our concept and to identify its energy bugs.