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71.
Gyulassy A Natarajan V Pascucci V Hamann B 《IEEE transactions on visualization and computer graphics》2007,13(6):1440-1447
The Morse-Smale complex is an efficient representation of the gradient behavior of a scalar function, and critical points paired by the complex identify topological features and their importance. We present an algorithm that constructs the Morse-Smale complex in a series of sweeps through the data, identifying various components of the complex in a consistent manner. All components of the complex, both geometric and topological, are computed, providing a complete decomposition of the domain. Efficiency is maintained by representing the geometry of the complex in terms of point sets. 相似文献
72.
Hoyer D Friedrich H Frank B Pompe B Baranowski R Zebrowski JJ Schmidt H 《Computer methods and programs in biomedicine》2006,81(3):246-255
Heart rate variability (HRV) represents the cardiovascular control mediated by the autonomic nervous system and other mechanisms. In the established task force HRV monitoring different cardiovascular control mechanisms can approximately be identified at typical frequencies of heart rate oscillations by power spectral analysis. HRV measures assessing complex and fractal behavior partly improved clinical risk stratification. However, their relationship to (patho-)physiology is not sufficiently explored. Objective of the present work is the introduction of complexity measures of different physiologically relevant time scales. This is achieved by a new concept of the autonomic information flow (AIF) analysis which was designed according to task force HRV. First applications show that different time scales of AIF improve the risk stratification of patients with multiple organ dysfunction syndrome and cardiac arrest patients in comparison to standard HRV. Each group's significant time scales correspond to their respective pathomechanisms. 相似文献
73.
Sudip Misra P. Venkata Krishna Akhil Bhiwal Amardeep Singh Chawla Bernd E. Wolfinger Changhoon Lee 《The Journal of supercomputing》2012,62(1):4-23
Reliable routing of packets in a Mobile Ad Hoc Network (MANET) has always been a major concern. The open medium and the susceptibility of the nodes of being fault-prone make the design of protocols for these networks a challenging task. The faults in these networks, which occur either due to the failure of nodes or due to reorganization, can eventuate to packet loss. Such losses degrade the performance of the routing protocols running on them. In this paper, we propose a routing algorithm, named as learning automata based fault-tolerant routing algorithm (LAFTRA), which is capable of routing in the presence of faulty nodes in MANETs using multipath routing. We have used the theory of Learning Automata (LA) for optimizing the selection of paths, reducing the overhead in the network, and for learning about the faulty nodes present in the network. The proposed algorithm can be juxtaposed to any existing routing protocol in a MANET. The results of simulation of our protocol using network simulator 2 (ns-2) shows the increase in packet delivery ratio and decrease in overhead compared to the existing protocols. The proposed protocol gains an edge over FTAR, E2FT by nearly 2% and by more than 10% when compared with AODV in terms of packet delivery ratio with nearly 30% faulty nodes in the network. The overhead generated by our protocol is lesser by 1% as compared to FTAR and by nearly 17% as compared to E2FT when there are nearly 30% faulty nodes. 相似文献
74.
Digital natives increasingly populate organizations?? management. These new-generation managers more naturally accept management support systems (MSS), but also have higher expectations about how they should accommodate their individual user preferences. As a result, managers question MSS that have been developed without configuration mechanisms to accommodate their working style, relevant MSS use cases, and different MSS access modes. The objective of this article is to reveal managers?? different MSS use situations and propose levers for tailoring (conceptual) MSS design to them. Use situations generalize classes of similar user-group preferences. We first apply findings from a literature review to cluster managers?? user-group preferences into 36 MSS use situations. Second, we propose that the selection of end-user devices can serve as a main lever for MSS configuration. Third, we complete the configuration with a MSS user-interface design. Finally, we demonstrate utility of our configuration model by presenting and evaluating a prototype. 相似文献
75.
Bernd Altmayer Klaus W. Eichhorn und Roland Plapp 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1982,175(3):172-174
Zusammenfassung Traubenmoste aus dem Weinanbaugebiet der Rheinpfalz wurden auf ihren Patulingehalt untersucht. Nach Extraktion und Reinigung wurde Patulin mit Hilfe der Hochleistungsflilssig- und Dünnschichtchromatographie bestimmt. Zur Extraktion des Patulins erwies sich die Verwendung von Extrelutsdulen als vorteilhaft. In 62% der untersuchten Proben (55) war kein Patulin nachweisbar, 22% enthielten weniger als 50 g, 16% mehr als 50 g Patulin pro Liter. Durch praxisübliche Mostschwefelung (100 mg Kaliumpyrosulîit/1) und Vergärung mit Hefen der GattungSaccharomyces konnte vorhandenes Patulin entfernt werden.
Analysis of patulin in grape juices and wine
Summary Grape juices from the wine-growing region of the palatinate Rheinpfalz were analysed for patulin. After extraction and purification patulin was determined by high performance liquid chromatography and thin layer chromatography. The use of Extrelut-columns for the extraction of patulin was found advantageous. 62% of the analysed samples (55) were free of patulin, 22% contained less than 50 g/l, 16% more than 50 g/l. By addition of sulfur dioxide to the must and fermentation withSaccharomyces sp. patulin could be removed from the samples.相似文献
76.
Andreas Heinrich Andreas L. Hrner Achim Wixforth Bernd Stritzker 《Thin solid films》2006,510(1-2):77-81
Surface Acoustic Waves on piezoelectric substrates can be used to investigate the dynamic conductivity of thin films in a non-contact and very sensitive way, especially at low conductivities. Here, we report on such surface acoustic wave studies to characterize thin manganite film like La0.67Ca0.33MnO3, exhibiting a Jan Teller effect with a strong electron phonon interaction and a metal insulator transition at high temperatures.
We report on the deposition of La0.67Ca0.33MnO3 on piezoelectric substrates (LiNbO3 in different crystal cuts, employing a pulsed laser deposition technique. The structural quality of the thin films are examined by X-Ray Diffraction, Scanning Electron Microscope and Energy Dispersive X-ray spectroscopy. For the electrical characterization, we employ the surface acoustic wave technique, accompanied by conventional direct current resistance measurements for comparison. 相似文献
77.
In deep X-ray lithography synchrotron radiation is applied to pattern several hundred micrometer thick resist layers. This
technique has been used to obtain micro structures with an aspect ratio up to 100 and dimensions in the micrometer range.
The structures are characterised by straight walls and a typical sidewall roughness of approximately 50 nm.
To be able to fabricate n-coherent structures with any lateral shape and to have the possibility to use these resist microstructures
in an additional electroforming process the resist is usually mounted on a ceramic or metallic substrate. Due to the different
thermal expansion coefficients of the resist material and the substrate a developing temperature of 37 °C produces cracks
in the resist structures depending on the microstructure design. These defects are not observed if the developing temperature
is reduced to 20 °C. Better structure quality is obtained using the GG-developer instead of MIBK/IPA, but the developing rate
is decreased. Measurements of the developing rate of PMMA in GG-developer at different temperatures show that the contrast
of the developer-resist system is increased at 20 °C compared to 37 °C.
Received: 25 August 1997/Accepted: 3 September 1997 相似文献
78.
Andrzej Dziech Przemysław Ślusarczyk Bernd Tibken 《Journal of Intelligent and Robotic Systems》2004,39(4):447-458
In this paper an image data compression scheme based on Periodic Haar Piecewise-Linear (PHL) transform and quantization tables is proposed. Effectiveness of the compression for different classes of images is evaluated. The comparison of the compression quality using PHL and DCT transforms is given. 相似文献
79.
Xue Yan Cui Benedicte Stavik Bernd Thiede Per Morten Sandset Sandip M. Kanse 《International journal of molecular sciences》2022,23(22)
Factor-VII-activating protease (FSAP) is involved in the regulation of hemostasis and inflammation. Extracellular histones play a role in inflammation and the conversion of latent pro-FSAP into active FSAP. FSAP has been shown to regulate endothelial permeability, but the mechanisms are not clear. Here, we have investigated the effects of FSAP on endothelial permeability in vitro. A mixture of histones from calf thymus stimulated permeability, and the wild-type (WT) serine protease domain (SPD) of FSAP blocked this effect. WT–SPD–FSAP did not influence permeability on its own, nor that stimulated by thrombin or vascular endothelial growth factor (VEGF)-A165. Histones induced a large-scale rearrangement of the junction proteins VE-cadherin and zona occludens-1 from a clear junctional distribution to a diffuse pattern. The presence of WT–SPD–FSAP inhibited these changes. Permeability changes by histones were blocked by both TLR-2 and TLR4 blocking antibodies. Histones upregulated the expression of TLR-2, but not TLR-4, in HUVEC cells, and WT–SPD–FSAP abolished the upregulation of TLR-2 expression. An inactive variant, Marburg I (MI)–SPD–FSAP, did not have any of these effects. The inhibition of histone-mediated permeability may be an important function of FSAP with relevance to sepsis, trauma, and stroke and the need to be investigated further in in vivo experiments. 相似文献
80.
Bernd Maienschein 《现代制造》2022,(2):42-43
<正>“Halle 2020”是Frankenthal市水泵和阀门生产厂KSB公司的一个扩建项目。这一项目不仅仅增加了KSB公司的生产面积,而且也扩展了KSB公司物流中心高架立体库的现代化和存储能力。Viastore公司收到了重建工厂的合同。 相似文献