Feature-interaction detection based on feature-based specifications

Formal specification and verification techniques have been used successfully to detect feature interactions. We investigate whether feature-based specifications can be used for this task. Feature-based specifications are a special class of specifications that aim at modularity in open-world, feature-oriented systems. The question we address is whether modularity of specifications impairs the ability to detect feature interactions, which cut across feature boundaries. In an exploratory study on 10 feature-oriented systems, we found that the majority of feature interactions could be detected based on feature-based specifications, but some specifications have not been modularized properly and require undesirable workarounds to modularization. Based on the study, we discuss the merits and limitations of feature-based specifications, as well as open issues and perspectives. A goal that underlies our work is to raise awareness of the importance and challenges of feature-based specification.     

Application of a territorial-based filtering algorithm in turbomachinery blade design optimization

A territorial-based filtering algorithm (TBFA) is proposed as an integration tool in a multi-level design optimization methodology. The design evaluation burden is split between low- and high-cost levels in order to properly balance the cost and required accuracy in different design stages, based on the characteristics and requirements of the case at hand. TBFA is in charge of connecting those levels by selecting a given number of geometrically different promising solutions from the low-cost level to be evaluated in the high-cost level. Two test case studies, a Francis runner and a transonic fan rotor, have demonstrated the robustness and functionality of TBFA in real industrial optimization problems.     

Understanding the Magnetic Shape Memory System Fe–Pd–X by Thin Film Experiments and First Principle Calculations

The magnetic shape memory (MSM) alloy Fe₇₀Pd₃₀ is of particular interest for novel microactuator and sensor applications. This review summarizes the underlying physical and material science concepts for this MSM alloy system. First‐principles calculations of the electronic and crystallographic structure together with combinatorial and epitaxial film studies are presented. By these complementary methods we can address the open key questions of MSM alloys and microsystems: Which are the driving forces for a martensitic transformation and how does this transformation proceed? How is it possible to improve the MSM properties by adding third elements? What is the role of external interfaces and which routes allow the preparation of freestanding epitaxial films?     

Polymer‐Based Spherical Activated Carbons in Combination with TS‐1 as Efficient Epoxidation Catalysts

The heterogeneously catalyzed epoxidation of commercially available biodiesel with aqueous H₂O₂ as an oxidant was studied over composite catalysts consisting of microporous titanium silicalite‐1 (TS‐1) as reactive and polymer‐based spherical activated carbon (PBSAC) as sorptive component. The results are compared to that of a commercial TS‐1 catalyst. The polymer‐based spherical activated carbon was applied either as a support or as an exotemplate. In the composite catalyst, the active titanium sites are utilized four times more efficiently than in the commercial TS‐1.