Finite Variation of Fractional Levy Processes

Various characterizations for fractional Levy process to be of finite variation are obtained, one of which is in terms of the characteristic triplet of the driving Levy process, while others are in terms of differentiability properties of the sample paths. A zero-one law and a formula for the expected total variation is also given.Comment: to appear in Journal of Theoretical Probabilit

KombiFiD - Kombinierte Firmendaten für Deutschland : Konzeption der Machbarkeitsstudie für eine Zusammenführung von Unternehmensdaten der Statistischen Ämter, des Instituts für Arbeitsmarkt- und Berufsforschung der Bundesagentur für Arbeit und weiterer Datenproduzenten (Combined firm data for Germany)

"Bei den Statistischen Ämtern des Bundes und der Länder und im Institut für Arbeitsmarkt- und Berufsforschung der Bundesagentur für Arbeit werden zahlreiche Daten für Unternehmen bzw. Betriebe gesammelt und aufbereitet. Durch das Unternehmensregister ist bei den Statistischen Ämtern eine 'Masterdatei' entstanden, die es technisch möglich macht, Unternehmensdaten aus den Beständen der genannten und weiteren Institutionen zusammenzuführen. Das Projekt KombiFiD - Kombinierte Firmendaten für Deutschland soll zeigen, dass ausgewählte Datenbestände tatsächlich über die Grenzen der jeweiligen Datenproduzenten zusammengeführt und der Wissenschaft zur Verfügung gestellt werden können, und es soll gleichzeitig demonstrieren, dass das Analysepotenzial dieser kombinierten Datensätze sehr viel höher ist als das der einzelnen Bestandteile. Der vorliegende Beitrag stellt die Konzeption dieses Projekts und das geplante Vorgehen vor." (Autorenreferat, IAB-Doku)Daten, Datengewinnung - Modellversuch, prozessproduzierte Daten, amtliche Statistik, Unternehmen, Wirtschaftsforschung, Wirtschaftsstatistik, Forschungsdatenzentrum, IAB, Statistisches Bundesamt

KombiFiD – Kombinierte Firmendaten für Deutschland

Bei den Statistischen Ämtern des Bundes und der Länder und im Institut für Arbeitsmarkt- und Berufsforschung der Bundesagentur für Arbeit werden zahlreiche Daten für Unternehmen bzw. Betriebe gesammelt und aufbereitet. Durch das Unternehmensregister ist bei den Statistischen Ämtern eine „Masterdatei“ entstanden, die es technisch möglich macht, Unternehmensdaten aus den Beständen der genannten und weiteren Institutionen zusammenzuführen. Das Projekt KombiFiD – Kombinierte Firmendaten für Deutschland soll zeigen, dass ausgewählte Datenbestände tatsächlich über die Grenzen der jeweiligen Datenproduzenten zusammengeführt und der Wissenschaft zur Verfügung gestellt werden können, und es soll gleichzeitig demonstrieren, dass das Analysepotenzial dieser kombinierten Datensätze sehr viel höher ist als das der einzelnen Bestandteile. Der vorliegende Beitrag stellt die Konzeption dieses Projekts und das geplante Vorgehen vor.

Standardized loads acting in knee implants

The loads acting in knee joints must be known for improving joint replacement, surgical procedures, physiotherapy, biomechanical computer simulations, and to advise patients with osteoarthritis or fractures about what activities to avoid. Such data would also allow verification of test standards for knee implants. This work analyzes data from 8 subjects with instrumented knee implants, which allowed measuring the contact forces and moments acting in the joint. The implants were powered inductively and the loads transmitted at radio frequency. The time courses of forces and moments during walking, stair climbing, and 6 more activities were averaged for subjects with I) average body weight and average load levels and II) high body weight and high load levels. During all investigated activities except jogging, the high force levels reached 3,372–4,218N. During slow jogging, they were up to 5,165N. The peak torque around the implant stem during walking was 10.5 Nm, which was higher than during all other activities including jogging. The transverse forces and the moments varied greatly between the subjects, especially during non-cyclic activities. The high load levels measured were mostly above those defined in the wear test ISO 14243. The loads defined in the ISO test standard should be adapted to the levels reported here. The new data will allow realistic investigations and improvements of joint replacement, surgical procedures for tendon repair, treatment of fractures, and others. Computer models of the load conditions in the lower extremities will become more realistic if the new data is used as a gold standard. However, due to the extreme individual variations of some load components, even the reported average load profiles can most likely not explain every failure of an implant or a surgical procedure

Why climate change adaptation in cities needs customised and flexible climate services

AbstractCities are key players in climate change adaptation and mitigation due to a spatial concentration of assets, people and economic activities. They are thus contributing to and especially vulnerable to climate change. Identifying, planning, implementing and monitoring respective measures in cities is challenging and resource consuming. The paper outlines challenges for adaptation, discusses most common approaches and argues why implementation of theoretical methods has its shortcomings. Based on case studies, an innovative, practice-oriented approach has been tested to develop a climate service prototype product. It provides a general framework that allows a flexible and customised support for cities to adapt to expected impacts of a changing climate

Effects of a wave power park with no-take zone on decapod abundance and size

Past studies have revealed higher levels of biodiversity, total abundance, and size of individuals around offshore installations of renewable energy. This study investigated the effects of Lysekil wave power park (area 0.5 km2) on the abundance and carapace size of decapods at the Swedish west coast. For that purpose, decapods were caught with cages during four consecutive summers. Two types of cages were applied to catch a wide range of decapod species and sizes. The abundance and size of decapods were not significantly different within the wave power park and up to a distance of 360 m outside of it. The catch rate, i.e., number of decapods caught in 24 h, was not significantly different among sampling locations but revealed inter-annual variation for both cage types. The results suggest a limited role of the incidental no-take zone of the small Lysekil wave power park on the abundance and size of local decapods. However, neither were negative impacts, such as decreasing abundances or smaller carapace sizes, discovered. As an increase in the number of marine renewable energy production sites is foreseen, a scaled-up and larger study addressing MPA networks and other environmental interactions should be considered

A Hand-held Laser Scanner based on Multi-camera Stereo-matching

Most laser scanners in engineering are extended versions of tactile measuring machines. These high precision devices are typically very expensive and hardware modifications are not possible without impairing the precision of the device. For these reasons we built our own laser-scanner system. It is based on a multi-camera reconstruction system developed for fast 3D face reconstructions. Based on this camera system, we developed a laser-scanner using GPU accelerated stereo-matching techniques and a hand-held line-laser probe. The resulting reconstruction is solely based on the known camera positions and parameters. Thus, it is not necessary to track the position and movement of the line-laser probe. This yields an inexpensive laser-scanner system where every hardware component can be modified individually for experiments and future extensions of the system