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International Journal of Digital Earth 2020年第12期13卷 1672-1694页

作者： Petr Klápště Michal Fogl Vojtěch Barták Kateřina Gdulová rudolf urban Vítězslav Moudrý Department of Applied Geoinformatics and Spatial Planning Faculty of Environmental SciencesCzech University of Life Sciences PragueKamýcká129Praha-Suchdol16500Czech Republic Department of Special Geodesy Faculty of Civil EngineeringCzech Technical University in PraguePragueCzech Republic

Most ground filtering algorithms are primarily designed for airborne LiDAR point cloud processing and their successful use in identifying ground points from photogrammetric point clouds remains *** compared six ground filtering algorithms implemented in Metashape,ArcGIS,CloudCompare,LAStools,and *** used UAV photogrammetry-based(acquired under leaf-off conditions)and airborne LiDAR(leaf-on)point clouds of the same area to:(i)compare accuracy of generated DTMs;(ii)evaluate the effect of vegetation density and terrain slope on filtering accuracy;and(iii)assess which algorithm parameters have the greatest effect on the filtering *** results show that the performance of filtering algorithms was affected by the point cloud type,terrain slope and vegetation *** results were generally better for LiDAR(RMSE 0.13–0.19 m)than for photogrammetric(RMSE 0.19–0.23 m)point *** behavior in varying vegetation and terrain conditions was consistent for LiDAR point ***,when applied on photogrammetric point clouds,the algorithms’behavior was inconsistent,especially in areas of steep slope(except for the Progressive Triangulated Irregular Network in LAStools).Parameters related to the selection of the initial minimum elevation ground points were the most influential in all algorithms and point clouds.

关键词： DTM filtering LiDAR point cloud spoil heap UAV

On Problems with Downscaling in Internal Flows

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Journal of Thermal Science 2005年第4期14卷 305-307页

作者： rudolf DVO■K Institute of Thermomechanics Academy of Sciences of the Czech RepublicDolejskova 5Prague 18200 Czech Republic

Problems that may accompany downscaling in internal flows are discussed. Non-dimensional similarity parameters （like Re, M, etc.） depend on parameters that scale down fully （e.g., length）, or that are specified by design （velocities, cascade geometry）, or that are scale invariant （like thermophysical and transport properties of fluids）.This fact has to be taken into acount in the similarity considerations. With decreasing Reynolds number the surface forces become of growing importance, however, if not going down directly to microflows the main problems are connected with the three-dimensional flow structure affecting the skin friction, and with the fact that some of the flow phenomena （e.g. vortical structures） cannot fully develop.

关键词： relatively narrow channels secondary flows skin friction microturbines.

Secondary Flow Effects in Relatively Narrow Channels

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Journal of Thermal Science 2003年第3期12卷 209-213,238页

作者： rudolf Dvo■ák Institute of Thermomechanics Academy of Sciences of the Czech Republic 182 00 Prague The Czech Republic

Secondary flow effects were discussed in numerous papers at the past ISAIF Symposia, mainly in connection with turbine or compressor cascades. This paper will complement these papers by looking at the problem from the channel (or blade passages) geometry point of view. If we describe as secondary flows any flows in planes perpendicular to the main flow direction, then there are at least three kinds of secondary flows in a typical turbine rotor cascade:-secondary flows of the 1st kind, generated by centrifugal forces in closed curved channels,-secondary flows of the 2nd kind, generated by interacting boundary layers, mainly in corners (this will include even the horseshoe vortices),-secondary flows due to mass inflow through the tip clearance.Quite often all the secondary flow vortices merge downstream into a passage vortex with a non-negligible contribution to the channel (cascade) losses, and it is worth investigating the individual contributions to these losses to take them into account in the design procedure.

关键词： channel flows secondary flows flow separation.

Stability Analysis of Equilibrium Manifolds for a Two-Predators One-Prey Model

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Tsinghua Science and Technology 2006年第6期11卷 739-744页

作者：张鑫唐云 rudolf Scherer Department of Mathematical Sciences Tsinghua University Institute of Practical Mathematics University of KarlsruheD-76128 KarlsruheGermany

The objective of this paper is to analyze the stability of equilibrium manifolds for a ratio-dependent two-predators one-prey model. Some model results are presented first with the bifurcation without parameters method, and then the method was used to study bifurcation along the equilibrium manifold for the model The model does not lose stability even when some equilibria are locally unstable because the equilibrium manifold is stable when treated as a whole. The ecological implications of the results are discussed.

关键词： bifurcation equilibrium manifold predator-prey model stability

How a membrane agent buys goods in a membrane store

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Progress in Natural Science:Materials International 2007年第4期17卷 442-448页

作者： rudolf Freund Marion Oswald Thomas Schirk Institute of Computer Languages Vienna University of Technology Favoritenstr. 9 WienAustria

In this paper we consider a specific model of membrane systems, i. e. membrane systems with attributes. In these systems, the information is placed at the membranes in form of attributes, no objects are considered inside the membranes except for other membranes. The membrane system with attributes evolves according to rules that compute new values for the attributes from the attributes assigned to the membranes involved in the rule. The model of membrane systems with attributes allows us to specify business transactions in a precise way and to simulate different models for such transactions with a suitable tool for membrane systems with attributes.

关键词： model membrane systems with attributes.

Sustained neuronal viability by paracrine factors: new opportunities for endothelial progenitor cell secretome

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Neural Regeneration Research 2021年第7期16卷 1429-1430页

作者： Stefano Di Santo Hans rudolf Widmer Department of Neurosurgery Neurocenter and Regenerative Neuroscience ClusterUniversity Hospital BernSwitzerland University of BernInselspitalSwitzerland

Despite the big progresses in the field of regenerative medicine, the loss of neurons remains essentially an unresolved *** the different approaches under investigation, there are great expectations on stem and progen... 详细信息

关键词： progenitor strategies. spite

Noninvasive diagnosis of hepatic fibrosis in chronic hepatitis C

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World Journal of Gastroenterology 2007年第32期13卷 4287-4294页

作者： rudolf E Stauber Carolin Lackner Department of Internal Medicine Medical University of GrazGrazAustria Institute of Pathology Medical University of GrazGrazAustria

Assessment of hepatic fibrosis is important for determining prognosis,guiding management decisions,and monitoring disease. Histological evaluation of liver biopsy specimens is currently considered the reference test for staging hepatic fibrosis. Since liver biopsy carries a small but significant risk,noninvasive tests to assess hepatic fibrosis are desirable. This editorial gives an overview on noninvasive methods currently available to determine hepatic fibrosis and their diagnostic accuracy for predicting significant fibrosis and cirrhosis in chronic hepatitis C. Based on available data,the performance of simple tests derived from routine laboratory parameters appears to be similar to that of more complex and expensive fibrosis panels. Transient elastography seems more accurate than blood tests for diagnosing cirrhosis.

关键词： Noninvasive fibrosis tests Significant fibrosis Cirrhosis Biomarkers Transient elastography

Pneumatic Measurements Downstream of a Radial Turbine Nozzle Cascade

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Journal of Thermal Science 2010年第1期19卷 42-46页

作者： Martin LUXA rudolf DVORAK David SIMURDA Jan VIMMR Department of Fluid Dynamics Institute of Thermomechanicsv.v.i.Academy of Science of the Czech RepublicPragueCzech Republic Department of Mechanics University of West Bohemia in PilsenPlzeňCzech Republic

This paper deals mainly with pneumatic measurements on a radial turbine nozzle cascade. The fill radial cascade guarantees the exit flow field periodicity downstream of it. A special traversing mechanism with a five - hole conical probe moving along a circular path behind the cascade was used for flow field investigation in this type of cascade with very low aspect ratio. The analyses of results of 2D and 3D pneumatic measurements including loss coefficient values are presented.

关键词： radial turbine cascade aspect ratio pneumatic measurement loss coefficient

IgE-Mast cell mediated allergy: a sensor of food quality

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Signal Transduction and Targeted Therapy 2024年第1期9卷 8-9页

作者： Christopher C.Udoye rudolf A.Manz Institute for Systemic Inflammation Research University of LübeckLübeckGermany

In two recent studies published in Nature,Florsheim et *** Plum et *** that allergic-specific reactions induced by immunoglobulin(Ig)E mediated mast cell activation is crucial for the timely induction of antigen-avoidance behaviour.1,2 These studies prove the concept that allergic sensitization triggers the formation of avoidance behaviour and define the underlying molecular mechanism.

关键词： allergic mechanism

Thermochemical Treatment——Technologies for Recovery and Utilisation of Materials

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过程工程学报 2006年第2期6卷 231-236页

作者： Gerd Kley rudolf Brenneis Burkart Adamczyk Franz-Georg Simon Division Waste Treatment and Remedial Eng. Federal Inst. Materials Research and Testing BAM Berlin 12200 Germany

The arc furnace technology is an ideally suited process for the treatment of hazardous and problematic waste. The operation conditions of the furnace can be adapted for optimal transformation of the waste material input into raw materials and usable products. The process can significantly reduce the impact of contaminated wastes and industrial residues, and enable material conversion and separation. Thus, the products of the process have various applications. The capability of the process is illustrated with three examples, the treatment of bottom ash and filter ash from waste incineration plants, of stainless steel slags and of chromium-containing residues from the refractory industry.

关键词：热化学处理原料分离耐火材料不锈钢