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Bar-Lev S.K.,Haifa University | Schulte-Geers E.,Bundesamt Fr Sicherheit in der Informationstechnik | Stadje W.,University of Osnabrck
Operations Research Letters | Year: 2011

The demand pooling anomaly of inventory theory of type F amounts to a kind of restricted order relation between the individual demands (assumed to be independent) and their average. In this paper, we present some sufficient conditions for the type F anomaly not to occur for two i.i.d. demands; furthermore we provide an asymptotic result showing whether this anomaly occurs for large n for a class of distributions containing all distributions with finite mean. © 2011 Elsevier B.V. All rights reserved. Source


Hein A.,OFFIS Institute for Information Technology | Winkelbach S.,TU Braunschweig | Martens B.,OFFIS Institute for Information Technology | Wilken O.,OFFIS Institute for Information Technology | And 7 more authors.
Informatics for Health and Social Care | Year: 2010

In this article, the design of a system for the ambient, unobtrusive and automatic monitoring of Activities of Daily Living (ADL) is described. In the context of the growing imbalance between (potentially young) caregivers and (most often older) people receiving care, technical monitoring systems may help to organise care more efficiently and to identify degrading abilities very early to trigger preventive measures. To improve the acceptance of the system described in this article, the selection process of the sensors to be integrated into the flat or to be worn by the older people has been steered by the results of focus group interviews with older people, their relatives and professional caregivers. The interviews revealed that these people would in general accept such systems, but security, mobility and communication aspects have to be clearly and appropriately addressed. In an experimental study the recognition rate of the activity 'preparation and intake of food or beverages' has been measured with two age groups (6 subjects, age between 25 and 40/mean 30 years and 5 subjects, age between 72 and 84/mean 75.3 years). The food preparation was detected with a sensitivity of 74.7 and a specificity of 84.2 using a vision sensor. © 2010 Informa UK, Ltd. Source


Foley J.A.,University of Edinburgh | Kaschel R.,University of Osnabrck | Logie R.H.,University of Edinburgh | Della Sala S.,University of Edinburgh
Archives of Clinical Neuropsychology | Year: 2011

Although several studies have shown that dual-tasking ability is impaired in Alzheimers disease (AD), the stage at which this deficit manifests remains unclear. This study investigated if a new paper-and-pencil assessment of dual-tasking ability could distinguish between AD, mild cognitive impairment (MCI) and normal ageing in a sample of 50 people with AD, 49 people with MCI, and 50 healthy age-matched controls. The AD group demonstrated a significant impairment in dual-task ability. There was no effect of either MCI or healthy ageing on dual-task performance, indicating that the dual-task impairment is specific to AD. © The Author 2011. Published by Oxford University Press. All rights reserved. Source


Finger H.,University of Osnabrck | Liu S.-C.,ETH Zurich
Proceedings - IEEE International Symposium on Circuits and Systems | Year: 2011

A binaural spike-based sound localization system suitable for real-time attention systems of robots is presented in this work. This system uses the output spikes from a 64-channel binaural silicon cochlea. The localization algorithm implements a spike-based correlation of these output spikes that measures the interaural time differences (ITDs) between the arrival of a sound to two microphones. The algorithm continuously updates a possible distribution of ITDs in the auditory scene whenever a spike arrives from either ear of the cochlea. Experimental results show that the system can estimate an azimuth angle to below 1 deg resolution. This algorithm is computationally cheaper than conventional generalized cross-correlation methods and is quicker to respond to changes in the scene. © 2011 IEEE. Source


Schaefer A.,University of Bremen | Gevers S.,University of Osnabrck | Zielasek V.,University of Bremen | Schroeder T.,Ihp Microelectronics | And 3 more authors.
Journal of Chemical Physics | Year: 2011

A cold radio frequency oxygen plasma treatment is demonstrated as a successful route to prepare clean, well-ordered, and stoichiometric PrO 2 layers on silicon. High structural quality of these layers is shown by x-ray diffraction. So far unobserved spectral characteristics in Pr 3d x-ray photoelectron (XP) spectra of PrO2 are presented as a fingerprint for praseodymia in its highest oxidized state. They provide insight in the electronic ground state and the special role of praseodymia among the rare earth oxides. They also reveal that former XP studies suffered from a significant reduction at the surface. © 2011 American Institute of Physics. Source

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