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61.
Marco Bakera Tiziana Margaria Clemens D. Renner Bernhard Steffen 《Innovations in Systems and Software Engineering》2009,5(3):211-228
We show on a case study from an autonomous aerospace context how to apply a game-based model-checking approach as a powerful
technique for the verification, diagnosis, and adaptation of system behaviors based on temporal properties. This work is part
of our contribution within the SHADOWS project, where we provide a number of enabling technologies for model-driven self-healing.
We propose here to use GEAR, a game-based model checker, as a user-friendly tool that can offer automatic proofs of critical
properties of such systems. Although it is a model checker for the full modal μ-calculus, it also supports derived, more user-oriented logics. With GEAR, designers and engineers can interactively investigate
automatically generated winning strategies for the games, by this way exploring the connection between the property, the system,
and the proof.
This work has been partially supported by the European Union Specific Targeted Research Project SHADOWS (IST-2006-35157), exploring a Self-Healing Approach to Designing cOmplex softWare Systems. The project’s web page is at .
This article is an extended version of Renner et al. [18] presented at ISoLA 2007, Poitiers, December 2007. 相似文献
62.
Helmut Reimer 《Datenschutz und Datensicherheit - DuD》2009,33(8):509-516
DuD Report
DuD Report 相似文献63.
Christoph Riedl Tilo Böhmann Michael Rosemann Helmut Krcmar 《Information Systems and E-Business Management》2009,7(2):199-221
Service-oriented architectures and Web services mature and have become more widely accepted and used by industry. This growing
adoption increased the demands for new ways of using Web service technology. Users start re-combining and mediating other
providers’ services in ways that have not been anticipated by their original provider. Within organisations and cross-organisational
communities, discoverable services are organised in repositories providing convenient access to adaptable end-to-end business
processes. This idea is captured in the term Service Ecosystem. This paper addresses the question of how quality management
can be performed in such service ecosystems. Service quality management is a key challenge when services are composed of a
dynamic set of heterogeneous sub-services from different service providers. This paper contributes to this important area
by developing a reference model of quality management in service ecosystems. We illustrate the application of the reference
model in an exploratory case study. With this case study, we show how the reference model helps to derive requirements for
the implementation and support of quality management in an exemplary service ecosystem in public administration. 相似文献
64.
Structure and Magnetic Property Control of Copper Hydroxide Acetate by Non‐Classical Crystallization
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RuiQi Song Theodora Krasia‐Christoforou Christian Debus Helmut Cölfen 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(9)
Copper hydroxide acetate (CHA), one layered hydroxide compound with tunable magnetism, attracts great interest because of its potential applications in memory devices. However, ferromagnetism for CHA is only demonstrated by means of GPa pressure. Herein, a new method is reported, involving the combination of different crystallization pathways to control crystallization of amorphous CHA toward the formation of CHA/polymer composites with tunable magnetic properties and even a tunability that can be tested at room temperature. By using poly[(ethylene glycol)6 methyl ether methacrylate]‐block‐poly[2‐(acetoacetoxy) ethyl methacrylate] (PEGMA‐b‐PAEMA) diblock copolymers as additives in combination with a post‐treatment process by ultracentrifugation, it is demonstrated that CHA and PEGMA‐b‐PAEMA form composites exhibiting different magnetic properties, depending on CHA in‐plane nanostructures. Analytical characterization reveals that crystallization of CHA is induced by ultracentrifugation, during which CHA nanostructures can be well controlled by changing the degrees of polymerization of the PEGMA and PAEMA blocks and their block length ratios. These findings not only present the first example of using crystallization from polymer stabilized amorphous precursors toward the generation of magnetic nanomaterials with tunable magnetism but also pave the way for the future design of functional composite materials. 相似文献
65.
Development of Highly Functional Biomaterials by Decoupling and Recombining Material Properties
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66.
Antony Jan Benjamin A. Reeves Yoeri van de Burgt Garrett J. Hayes Bruce M. Clemens 《Advanced Engineering Materials》2018,20(1)
67.
Reasoning about change is a central issue in research on human and robot planning. We study an approach to reasoning about action and change in a dynamic logic setting and provide a solution to problems which are related to the Frame problem. Unlike most work on the frame problem the logic described in this paper is monotonic. It (implicitly) allows for the occurrence of actions of multiple agents by introducing non-stationary notions of waiting and test. The need to state a large number of frame axioms is alleviated by introducing a concept of chronological preservation to dynamic logic. As a side effect, this concept permits the encoding of temporal properties in a natural way. We compare the relative merits of our approach and non-monotonic approaches as regards different aspects of the frame problem. Technically, we show that the resulting extended systems of propositional dynamic logic preserve (weak) completeness, finite model property and decidability. 相似文献
68.
Web spam denotes the manipulation of web pages with the sole intent to raise their position in search engine rankings. Since
a better position in the rankings directly and positively affects the number of visits to a site, attackers use different
techniques to boost their pages to higher ranks. In the best case, web spam pages are a nuisance that provide undeserved advertisement
revenues to the page owners. In the worst case, these pages pose a threat to Internet users by hosting malicious content and
launching drive-by attacks against unsuspecting victims. When successful, these drive-by attacks then install malware on the
victims’ machines. In this paper, we introduce an approach to detect web spam pages in the list of results that are returned
by a search engine. In a first step, we determine the importance of different page features to the ranking in search engine
results. Based on this information, we develop a classification technique that uses important features to successfully distinguish
spam sites from legitimate entries. By removing spam sites from the results, more slots are available to links that point
to pages with useful content. Additionally, and more importantly, the threat posed by malicious web sites can be mitigated,
reducing the risk for users to get infected by malicious code that spreads via drive-by attacks. 相似文献
69.
Matthias Winter Gregor Feiertag Anton Leidl Helmut Seidel 《Microsystem Technologies》2010,16(5):809-815
This paper describes the influence of a chip scale MEMS package (CSMP) on the acoustic behaviour of a silicon microphone.
The influence was calculated using an electro-mechanical–acoustical equivalent circuit. Standard packaging of microphones
using die bonding and wire bonding leads to a large front volume which acts as a Helmholtz resonator. This can dramatically
influence the frequency response of the microphone system by adding a second resonance. In the worst case this second resonance
is in the acoustic frequency range, thus degrading its performance in an unacceptable way. In case of the CSMP only a small
front volume is generated between the substrate and the flip-chipped microphone chip. Thus the resonance step-up is very small
compared to standard packages. Furthermore the frequency response can be flattened by optimizing the geometry of the small
sound holes in the substrate. By choosing an appropriate geometry of these sound holes the package can act as a low pass filter
where the cut-off frequency can be placed to the desired value of the acoustic spectrum. 相似文献
70.