Perceptually‐motivated Real‐time Temporal Upsampling of 3D Content for High‐refresh‐rate Displays

High‐refresh‐rate displays (e. g., 120 Hz) have recently become available on the consumer market and quickly gain on popularity. One of their aims is to reduce the perceived blur created by moving objects that are tracked by the human eye. However, an improvement is only achieved if the video stream is produced at the same high refresh rate (i. e. 120 Hz). Some devices, such as LCD TVs, solve this problem by converting low‐refresh‐rate content (i. e. 50 Hz PAL) into a higher temporal resolution (i. e. 200 Hz) based on two‐dimensional optical flow. In our approach, we will show how rendered three‐dimensional images produced by recent graphics hardware can be up‐sampled more efficiently resulting in higher quality at the same time. Our algorithm relies on several perceptual findings and preserves the naturalness of the original sequence. A psychophysical study validates our approach and illustrates that temporally up‐sampled video streams are preferred over the standard low‐rate input by the majority of users. We show that our solution improves task performance on high‐refresh‐rate displays.     

Bases for Boolean co-clones

The complexity of various problems in connection with Boolean constraints, like, for example, quantified Boolean constraint satisfaction, have been studied recently. Depending on what types of constraints may be used, the complexity of such problems varies. A very interesting observation of the recent past has been that the thus derived classification of constraints can be explained with the help of universal algebra. More precisely, the difficulty of such a constraint problem often depends on the co-clone the constraints are from. A co-clone is a set of Boolean relations that is closed under very natural closure operations. Nearly all these co-clones can be generated by said operators out of a finite set of relations, a so-called base. Knowing a, preferably simple, base for each co-clone can therefore be of great value when studying the complexity of Boolean constraint problems, since this knowledge reduces the infinitely many cases of equivalent problems to a single one—the constraint satisfaction problem for this base. In this paper we give a finite and simple base for every Boolean co-clone, where this is possible. We give evidence that the presented bases are as easy as possible.     

Reductive Decyanation of Annulated Aminocyclopropane-endo-carbonitriles – a way to annulated cyclopropane-exo-amines

Annulated Aminocyclopropane-endo-carbonitriles 11a,b are reductively decyanated by sodium in liquid ammonia with complete retention of configuration. An additionally existing chlorine atom in the starting materials 12a,c – e , thereby, is simulataneously replaced by hydrogen. The preparative advantage of this method is demonstrated by the selective access to 6α-H-isomers 13b and 13e as members of the ensemble of bicyclo[3.1.0]hexanediyl-dimorpholine diastereomers. A strong buckled bicyclohexane unit is present in 3α,6αisomer 13e as indicated by ¹H NMR spectroscopy and X-ray structural analysis.     

A Structure-Activity Relationship Study of Bimodal BODIPY-Labeled PSMA-Targeting Bioconjugates

The aim of this study was to identify a high-affinity BODIPY peptidomimetic that targets the prostate-specific membrane antigen (PSMA) as a potential bimodal imaging probe for prostate cancer. For the structure-activity study, several BODIPY (difluoroboron dipyrromethene) derivatives with varying spacers between the BODIPY dye and the PSMA Glu-CO-Lys binding motif were prepared. Corresponding affinities were determined by competitive binding assays in PSMA-positive LNCaP cells. One compound was identified with comparable affinity (IC₅₀=21.5±0.1 nM) to Glu-CO-Lys-Ahx-HBED-CC (PSMA-11) (IC₅₀=18.4±0.2 nM). Radiolabeling was achieved by Lewis-acid-mediated ¹⁹F/¹⁸F exchange in moderate molar activities (∼0.7 MBq nmol⁻¹) and high radiochemical purities (>99 %) with mean radiochemical yields of 20–30 %. Cell internalization of the ¹⁸F-labeled high-affinity conjugate was demonstrated in LNCaP cells showing gradual increasing PSMA-mediated internalization over time. By fluorescence microscopy, localization of the high-affinity BODIPY-PSMA conjugate was found in the cell membrane at early time points and also in subcellular compartments at later time points. In summary, a high-affinity BODIPY-PSMA conjugate has been identified as a suitable candidate for the development of PSMA-specific dual-imaging agents.     

Generating tool paths on surfaces for a numerically controlled calotte cutting system

Non-planar driving mirrors have a complex geometry, which is defined by a base surface (the so-called calotte) and a planar contour. We describe and compare methods for generating NC tool paths for a calotte cutting machine from these data. The methods are based on piecewise circular arcs and on polynomial spline curves. Distance bounds for the resulting tool paths, which are needed in order to check the accuracy, are also discussed. The paper concludes with suggestions for research on the use of Pythagorean hodograph curves in industrial NC tool path generation.     

Voltage-Controlled Electron-Hole Interaction in a Single Quantum Dot

The ground state of neutral and negatively charged excitons confined to a single self-assembled InGaAs quantum dot is probed in a direct absorption experiment by high resolution laser spectroscopy. We show how the anisotropic electron-hole exchange interaction depends on the exciton charge and demonstrate how the interaction can be switched on and off with a small dc voltage. Furthermore, we report polarization sensitive analysis of the excitonic interband transition in a single quantum dot as a function of charge with and without magnetic field.     

Vergleichende Untersuchung raumakustischer Konzepte von Mehrpersonenbüros hinsichtlich Sprachverständlichkeit,Arbeitsgedächtnisleistung und Arbeitsbehaglichkeit durch Hörversuche

Comparative studies of room‐acoustic concepts for open‐plan offices with regard to speech intelligibility, short‐term memory perfomance and acoustic comfort. Increasing use of tempering the core of reeinforced concrete ceilings of open‐plan offices for cooling and if necessary for heating strongly limits the implementation of sound‐absorbing ceilings. In these cases the classic concept for offices with fully sound‐absorbing ceilings and screen barriers is not applicable anymore. As an alternative to this concept of screen barriers a so‐called partition wall concept is going to be implemented in these open‐plan offices. In this case a sound‐absorbing ceiling is not used anymore; instead room‐high partition walls are mounted, which are highly sound‐absorbing on both sides. The objective of the study was to compare these two concepts for open‐plan offices regarding speech intelligibility on the phone, ability to concentrate and acoustic comfort. In addition to that the effect of low‐frequency absorbers was investigated. To evaluate the acoustic concepts of theses offices audibility tests were conducted. For this purpose the room‐acoustic conditions of the office situations were auralized with the help of measured binaural room impulse responses of original open‐plan offices. For comparison an open‐plan office without room‐acoustic measures was included. With this procedure different office situations are directly comparable.