2,472 research outputs found
Intermediate host patterns of acanthocephalans in the Weser river system: Co-invasion versus host-capture
Increasing System Test Coverage in Production Automation Systems
An approach is introduced, which supports a testing technician in the
identification of possibly untested behavior of control software of fully
integrated automated production systems (aPS). Based on an approach for guided
semi-automatic system testing, execution traces are recorded during testing,
allowing a subsequent coverage assessment. As the behavior of an aPS is highly
dependent on the software, omitted system behavior can be identified and
assessed for criticality. Through close cooperation with industry, this
approach represents the first coverage assessment approach for system testing
in production automation to be applied on real industrial objects and evaluated
by industrial experts
Industrially Applicable System Regression Test Prioritization in Production Automation
When changes are performed on an automated production system (aPS), new
faults can be accidentally introduced in the system, which are called
regressions. A common method for finding these faults is regression testing. In
most cases, this regression testing process is performed under high time
pressure and on-site in a very uncomfortable environment. Until now, there is
no automated support for finding and prioritizing system test cases regarding
the fully integrated aPS that are suitable for finding regressions. Thus, the
testing technician has to rely on personal intuition and experience, possibly
choosing an inappropriate order of test cases, finding regressions at a very
late stage of the test run. Using a suitable prioritization, this iterative
process of finding and fixing regressions can be streamlined and a lot of time
can be saved by executing test cases likely to identify new regressions
earlier. Thus, an approach is presented in this paper that uses previously
acquired runtime data from past test executions and performs a change
identification and impact analysis to prioritize test cases that have a high
probability to unveil regressions caused by side effects of a system change.
The approach was developed in cooperation with reputable industrial partners
active in the field of aPS engineering, ensuring a development in line with
industrial requirements. An industrial case study and an expert evaluation were
performed, showing promising results.Comment: 13 pages, https://ieeexplore.ieee.org/abstract/document/8320514
Fachdidaktische Analysekompetenz zum Umgang mit Darstellungen â Vignettenbasierte Erhebung mit Texten, Comics und Videos
Setzt man Vignetten zur Kompetenzmessung bei Lehramtsstudierenden
und praktizierenden LehrkrÀften ein, wird durch den Bezug zu konkreten
Situationen eine unterrichtsnahe Erhebung fachdidaktischer Kompetenzaspekte
ermöglicht. FĂŒr die inhaltsbereichsspezifische Messung fachdidaktischer
Analysekompetenz zum Umgang mit Darstellungen werden im Folgenden
theoretische Grundlagen skizziert, verschiedene Erhebungsformate
diskutiert und ein entsprechendes Forschungsdesign vorgestellt
Videos, Comics oder Texte? Vergleich verschiedener Vignettenformate zur Erhebung fachdidaktischer Analysekompetenz von LehrkrÀften in Ausbildung und Praxis
On continuum modeling of sputter erosion under normal incidence: interplay between nonlocality and nonlinearity
Under specific experimental circumstances, sputter erosion on semiconductor
materials exhibits highly ordered hexagonal dot-like nanostructures. In a
recent attempt to theoretically understand this pattern forming process, Facsko
et al. [Phys. Rev. B 69, 153412 (2004)] suggested a nonlocal, damped
Kuramoto-Sivashinsky equation as a potential candidate for an adequate
continuum model of this self-organizing process. In this study we theoretically
investigate this proposal by (i) formally deriving such a nonlocal equation as
minimal model from balance considerations, (ii) showing that it can be exactly
mapped to a local, damped Kuramoto-Sivashinsky equation, and (iii) inspecting
the consequences of the resulting non-stationary erosion dynamics.Comment: 7 pages, 2 Postscript figures, accepted by Phys. Rev. B corrected
typos, few minor change
Automated root cause isolation in performance regression testing
Testing of software is an important aspect of software development. There exist multiple kinds of tests, like unit tests and integration tests. The tests this thesis will focus on will be load tests, which are used to observe a systemâs behavior under load. The presented approach will use these load tests in order to observe and analyze the performance of a system, like e.g. the response times of methods. Next these observations are compared with those made on other versions of the system, in order to detect performance regressions, deteriorations in performance, between versions. Another goal of the approach will be to identify the root cause of the regressions, which is the source code change responsible for introducing them. By doing this, the task of fixing this problem will be made easier for the software engineer, since he has an entry point for the problem.Das Testen von Software ist ein wichtiger Bestandteil der Software-Entwicklung. Es existieren viele Arten von Tests, wie Unit-Tests und Integrationstests. Die Tests, auf welche sich diese Thesis fokussiert, sind Lasttests. Diese werden genutzt um zu beobachten, wie ein System sich unter Belastung verhĂ€lt. Der vorgestellte Ansatz wird diese Lasttests nutzen, um das Betriebsverhalten eines Systems zu erfassen und analysieren, wie z.B. das Antwortzeitverhalten von einzelnen Methoden. Als NĂ€chstes werden diese Beobachtungen mit denen verglichen, die auf anderen Versionen des Systems gemacht wurden, um Regressionen im Betriebsverhalten, wie Verschlechterungen des Antwortzeitverhaltens, zwischen den Versionen zu finden. Ein weiteres Ziel des Ansatzes wird es sein, die Hauptursache einer Regression zu identifizieren, welches die QuellcodeĂ€nderung ist, die fuÌr die EinfuÌhrung der Regression verantwortlich ist. Dies wird es dem Software-Entwickler, der beauftragt wurde die Regression zu verbessern, einfacher machen dies zu tun, da er bereits einen festen Ansatzpunkt geliefert bekommen hat
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