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61.
This paper examines and classifies the computational complexity of model checking and satisfiability for hybrid logics over
frames with equivalence relations. The considered languages contain all possible combinations of the downarrow binder, the
existential binder, the satisfaction operator, and the global modality, ranging from the minimal hybrid language to very expressive
languages. For model checking, we separate polynomial-time solvable from PSPACE-complete cases, and for satisfiability, we
exhibit cases complete for NP, PSpace, NExpTime, and even N2ExpTime. Our analysis includes the versions of all these languages without atomic propositions, and also complete frames. 相似文献
62.
Vasileios Belagiannis Xinchao Wang Horesh Beny Ben Shitrit Kiyoshi Hashimoto Ralf Stauder Yoshimitsu Aoki Michael Kranzfelder Armin Schneider Pascal Fua Slobodan Ilic Hubertus Feussner Nassir Navab 《Machine Vision and Applications》2016,27(7):1035-1046
Multiple human pose estimation is an important yet challenging problem. In an operating room (OR) environment, the 3D body poses of surgeons and medical staff can provide important clues for surgical workflow analysis. For that purpose, we propose an algorithm for localizing and recovering body poses of multiple human in an OR environment under a multi-camera setup. Our model builds on 3D Pictorial Structures and 2D body part localization across all camera views, using convolutional neural networks (ConvNets). To evaluate our algorithm, we introduce a dataset captured in a real OR environment. Our dataset is unique, challenging and publicly available with annotated ground truths. Our proposed algorithm yields to promising pose estimation results on this dataset. 相似文献
63.
64.
Jens MaßbergJan Schneider 《Theoretical computer science》2011,412(50):6948-6958
We formulate a generalization of the NP-complete rectangle packing problem by parameterizing it in terms of packing density, the ratio of rectangle areas, and the aspect ratio of individual rectangles. Then we show that almost all restrictions of this problem remain NP-complete and identify some cases where the answer to the decision problem can be found in constant time. 相似文献
65.
Human eye-head co-ordination in natural exploration 总被引:1,自引:0,他引:1
Einhäuser W Schumann F Bardins S Bartl K Böning G Schneider E König P 《Network (Bristol, England)》2007,18(3):267-297
During natural behavior humans continuously adjust their gaze by moving head and eyes, yielding rich dynamics of the retinal input. Sensory coding models, however, typically assume visual input as smooth or a sequence of static images interleaved by volitional gaze shifts. Are these assumptions valid during free exploration behavior in natural environments? We used an innovative technique to simultaneously record gaze and head movements in humans, who freely explored various environments (forest, train station, apartment). Most movements occur along the cardinal axes, and the predominance of vertical or horizontal movements depends on the environment. Eye and head movements co-occur more frequently than their individual statistics predicts under an independence assumption. The majority of co-occurring movements point in opposite directions, consistent with a gaze-stabilizing role of eye movements. Nevertheless, a substantial fraction of eye movements point in the same direction as co-occurring head movements. Even under the very most conservative assumptions, saccadic eye movements alone cannot account for these synergistic movements. Hence nonsaccadic eye movements that interact synergistically with head movements to adjust gaze cannot be neglected in natural visual input. Natural retinal input is continuously dynamic, and cannot be faithfully modeled as a mere sequence of static frames with interleaved large saccades. 相似文献
66.
Kriger J Schneider J Westermann R 《IEEE transactions on visualization and computer graphics》2006,12(5):941-948
Volume rendered imagery often includes a barrage of 3D information like shape, appearance and topology of complex structures, and it thus quickly overwhelms the user. In particular, when focusing on a specific region a user cannot observe the relationship between various structures unless he has a mental picture of the entire data. In this paper we present ClearView, a GPU-based, interactive framework for texture-based volume ray-casting that allows users which do not have the visualization skills for this mental exercise to quickly obtain a picture of the data in a very intuitive and user-friendly way. ClearView is designed to enable the user to focus on particular areas in the data while preserving context information without visual clutter. ClearView does not require additional feature volumes as it derives any features in the data from image information only. A simple point-and-click interface enables the user to interactively highlight structures in the data. ClearView provides an easy to use interface to complex volumetric data as it only uses transparency in combination with a few specific shaders to convey focus and context information. 相似文献
67.
68.
Rudolf Treleano Hans-Dieter Belitz Harald Jugel und Herbert Wieser 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1978,167(5):320-323
Zusammenfassung 1-Aminocycloalkan-l-carbonsäuren mit Ringgrößen von 4–11 (ohne 10) wurden synthetisiert und auf ihre Geschmackseigenschaften untersucht. Süßer Geschmack tritt vom 4-Ring bis zum 8-Ring auf, beim 6-Ring ist der Schwellenwert minimal (c
Ssü=1–3 mmol/l). Bitter sind die Verbindungen vom 5-Ring bis zum 9-Ring, das Minimum des Schwellenwertes liegt beim 8-Ring (c
sbi=2–5 mmol/l). Die größeren Ringe sind bis zu Konzentrationen von 20 mmol/l ohne Geschmack. Beim 6-Ring löscht eine 2-Methylgruppe jeden Geschmackseindruck, während die 3- und 4-Methylverbindungen süß und bitter sind. Die 4-Äthylverbindung ist bitter aber nicht süß, die 4-tert.-Butylverbindung ist ohne Geschmack. 1-Aminonorbornan-1-carbonsäure ist süß (c
Ssü 50 mmol/l) und bitter (c
sbi=5–7mmo1/1), wobei der Schwellenwert für bitter fast eine Zehnerpotenz kleiner ist. tert.-Leucin ist ohne Geschmack. Die Ergebnisse werden im Zusammenhang mit früheren Untersuchungen an offenkettigen Aminosäuren diskutiert und in Modelle über sterische Voraussetzungen für Geschmack eingeordnet.
Relationsships between structure and taste in amino acids with cyclic side chains
Summary 1-Aminocycloalkane-1-carboxylic acids with ring sizes of 4–11 (excluding 10) were synthesized and tested for their taste properties. The compounds with 4- to 8-membered rings are sweet, with threshold values going through a minimum for the 6-membered ring (c tsw = l-3 mM/l). The compounds with 5- to 9-membered rings are bitter. Here the threshold value reaches a minimum for the 8-membered ring (c tbi=2–5 mM/l). The larger rings are without taste up to concentrations of 20 mmol/l. With the 6-membered ring a 2-methyl group abolishes any taste impression, whereas the 3- and 4-methyl compounds are sweet and bitter. The 4-ethyl compound is bitter but not sweet, the 4-tert.-butyl compound has no taste. 1-Aminonorbornane-l-carboxylic acid is sweet (c tsw 50mM/l) and bitter (c tbi= 5–7 mM/l), withc tbi being significantly smaller thanc tsw. tert-Leucine is without taste. The results are discussed in relation to previous investigations into steric prerequisites for taste in the amino acid series.相似文献
69.
Future high-performance computing (HPC) architectures will consist of whole parallel computing systems integrated on chip-level and boards mounted with lots of computing chips and chip-external main memory. Photonic networks on board and photonic network on chips (NoCs) offer the potential to fulfill the high bandwidth requirements in such systems. In addition they need less power, offer better EMC capabilities and can reduce cabling effort compared to electronic networks. Due to their non-blocking property Clos networks are frequently used in HPC architectures. Therefore we investigated how a photonic on-board Clos network can be realized using Coarse Wavelength-Division-Multiplexing (CWDM) techniques with state-of-the art components based on fiber technology. In addition we present a new photonic Clos NoC architecture based on Wavelength Interchanging (WI) elements, optical waveguide structures, mode-locked laser sources, nanophotonic microrings and passive optical deflection elements to reduce the number of switches. We discuss the benefits and drawbacks for using different optical technologies for such an architecture. 相似文献
70.
Thin films of single-phase A15 Nb3Al were irradiated with protons and nitrogen ions. X-ray intensity analysis revealed a decrease of the Bragg-Williams long-range order parameterS and an increase of the average displacement amplitude of the atomsU
in the fluence region where a decrease of the superconducting transition temperatureT
c was observed. The functional dependence ofT
c onS andU
was found to depend on the ion species used for irradiation. After irradiation with 1016 N2+ / cm2 the A15 phase transformed into an A2 phase. Furnace annealing caused a retransformation into the A15 phase with improved superconducting properties. 相似文献