Rational extensions of the representation ring global functor and a splitting of global equivariant KK-theory

We identify the group of homomorphisms $\operatorname{Hom}_{\mathcal{GF}}(F,\mathbf{RU}_{\mathbb Q})$ in the category of ($\operatorname{fin}$)-global functors to the rationalization of the unitary representation ring functor and deduce that the higher $\operatorname{Ext}$-groups $\operatorname{Ext}^n_{\mathcal{GF}}(F,\mathbf{RU}_{\mathbb Q})$, $n\geq 2$ have to vanish. This leads to a rational splitting of the ($\operatorname{fin}$)-global equivariant $K$-theory spectrum into a sum of Eilenberg-MacLane spectra. Interpreted in terms of cohomology theories, it means that the equivariant Chern character is compatible with restrictions along all group homomorphisms.Comment: 10 page

Array bounds check elimination in the context of deoptimization

AbstractWhenever an array element is accessed, Java virtual machines execute a compare instruction to ensure that the index value is within the valid bounds. This reduces the execution speed of Java programs. Array bounds check elimination identifies situations in which such checks are redundant and can be removed. We present an array bounds check elimination algorithm for the Java HotSpot™ VM based on static analysis in the just-in-time compiler.The algorithm works on an intermediate representation in static single assignment form and maintains conditions for index expressions. It fully removes bounds checks if it can be proven that they never fail. Whenever possible, it moves bounds checks out of loops. The static number of checks remains the same, but a check inside a loop is likely to be executed more often. If such a check fails, the executing program falls back to interpreted mode, avoiding the problem that an exception is thrown at the wrong place.The evaluation shows a speedup near to the theoretical maximum for the scientific SciMark benchmark suite and also significant improvements for some Java Grande benchmarks. The algorithm slightly increases the execution speed for the SPECjvm98 benchmark suite. The evaluation of the DaCapo benchmarks shows that array bounds checks do not have a significant impact on the performance of object-oriented applications

The spectrum of derived Mackey functors

Peer reviewedPostprin

Software in the Manufacturing Industry: A Review of Security Challenges and Implications

Software defines digital infrastructures in the manufacturing industry, connecting services and computation resources to machines and devices. These infrastructures aim at increased flexibility, scalability, and a wider application portfolio for automated manufacturing processes. At the same time, the complexity of securing software increases dramatically. Threats to confidentiality, integrity, and availability of software can result in critical losses for automated industrial production and impact manufacturing companies. In order to map existing and emerging security challenges, we present the results of a hermeneutic literature review structured along abstraction levels and vertical integration of software. Based on this structure, we derive implications for academia and practice focused on operators, developers, and security auditors of digital infrastructures. Thereby, we discuss courses of action mapped to software security black boxes, infrastructure heterogeneity, and the adaptation of security for operational usage

Studying eParticipation in Government Innovation Programmes: Lessons from a Survey

While eGovernment is a well-established field in research and practice, eParticipation trails behind with only a low number of programmes and strategies at the moment. With the lessons learnt from a survey for studying eParticipation in Government Innovation Programmes and Strategies, the contribution at hand analyses the degree of integration of eParticipation in ICT and eGovernment research and implementation programmes and strategies. It sets out the types of approach necessary to accelerate progress. Together with insights from two projects that analysed eGovernment innovation strategies, the synthesis and comparison of the survey data led to recommendations for activities and measures for innovation programme managers to include eParticipation in future programmes and strategies. The work was performed in the context of DEMO_net1, the Network of Excellence on eParticipation