On the determination of heliographic positions and rotation velocities of sunspots     

Horst Balthasar  Hubertus Wöhl 《Solar physics》1983,84(1-2):71-75

The north-south asymmetry in the intensity of the 530.3 nm emission coronal line is examined in the time period 1958 to 1980 using data at all latitudes. The results show that overall the northern hemisphere of the Sun is more active in this line. The general pattern has changed after the beginning of the 21st cycle with the southern polar region being more active after the last solar minimum (1975). These anisotropies may be related to phase differences between the activity of northern and southern hemispheres. North-south asymmetries may have implications in the structure and evolution of the heliosphere, its current sheet and even in the cosmic ray propagation.  相似文献   

Evidence for a nitrogen flux directly derived from the European subcontinental mantle in the Western Eger Rift, Central Europe   总被引：1，自引：0，他引：1  

Karin Bräuer  Horst Kämpf  Gerhard Strauch 《Geochimica et cosmochimica acta》2004,68(23):4935-4947

In the Czech-German border region of the Vogtland and NW Bohemia (western Eger rift, Central Europe), chemical and isotopic compositions (C, N, He, Ar) of free gas from a thermal water escape (fluorite mine, Schönbrunn), two mineral springs (“Eisenquelle,” Bad Brambach; “Sprudel III,” Bad Elster) and a mofette (Bublak) located along an ∼40-km long traverse are reported. The gases of Bublak and Bad Brambach are CO₂-rich (>99 vol.%) and have δ¹³C values of −1.95 and −4.29‰, respectively. With distance from the center of CO₂ degassing (Bublak) the δ¹³C values decrease, most likely due to physico-chemical fractionation of CO₂ between gaseous and aqueous phases rather than to admixture of organic/biogenic CO₂. The δ¹⁵N values range between −3.2 and −0.6‰, compared to an upper mantle value of −4.0 ± 1.0‰. The four locations are characterized by ³He/⁴He ratios decreasing from 5.9 R_a in the center (Bublak) to 0.8 R_a in the periphery (Schönbrunn) and give evidence for mixing of He from a deep-seated magmatic source with a crustal source. The location with the highest ³He/⁴He ratio (5.9 R_a) is accompanied by the highest ⁴⁰Ar/³⁶Ar (550). We argue that the nitrogen of the Bublak mofette gas is a mixture of predominantly atmospheric and mantle-derived components, whereas at the other three locations crustal nitrogen may also be present. The Bublak δ¹⁵N value of ≈−4.5 ± 1.0‰ represents the first free gas δ¹⁵N reference from the European subcontinental mantle (ESCM) and indicates that, in contrast to the ³He/⁴He ratios, the δ¹⁵N values are equal for ESCM and MORB, respectively.  相似文献   

Dynamic finite element analysis of three-dimensional soil models with a transmitting element     

Horst Werkle 《地震工程与结构动力学》1986,14(1):41-60

A method for the dynamic finite element analysis of a non-axisymmetric soil model with an axisymmetric boundary is presented. In the non-axisymmetric soil domain an arbitrary discretization with three-dimensional isoparametric solid elements is used. At the boundary a transmitting element is arranged. It is based on the semi-analytical element of Waas and Kausel. The transformation of the stiffness matrix of the Waas/Kausel element with cyclic symmetric displacements to general displacement fields is presented. For earthquake excitation the forces acting on the discretized domain are given. The method is illustrated by the dynamic analysis of an embedded box-type building. The distribution and magnitude of significant section forces are discussed.  相似文献   

On the determination of heliographic positions and rotation velocities of sunspots     

Horst Balthasar  Günter Lustig  Hubertus Wöhl 《Solar physics》1984,91(1):55-59

In an earlier paper of this series it was shown how the Wilson depression influences the determination of sunspot rotation velocities. Using this finding and the fact that stable recurrent sunspots show a very constant rotation velocity it is possible to determine the effect of wrong solar image radii on the determination of sunspot rotation velocities and correct them.Mitteilungen aus dem Kiepenheuer-Institut Nr. 238.  相似文献   

Semantic enrichment of octree structured point clouds for multi‐story 3D pathfinding          下载免费PDF全文

Florian W. Fichtner  Abdoulaye A. Diakité  Sisi Zlatanova  Robert Voûte 《Transactions in GIS》2018,22(1):233-248

3D indoor navigation in multi‐story buildings and under changing environments is still difficult to perform. 3D models of buildings are commonly not available or outdated. 3D point clouds turned out to be a very practical way to capture 3D interior spaces and provide a notion of an empty space. Therefore, pathfinding in point clouds is rapidly emerging. However, processing of raw point clouds can be very expensive, as these are semantically poor and unstructured data. In this article we present an innovative octree‐based approach for processing of 3D indoor point clouds for the purpose of multi‐story pathfinding. We semantically identify the construction elements, which are of importance for the indoor navigation of humans (i.e., floors, walls, stairs, and obstacles), and use these to delineate the available navigable space. To illustrate the usability of this approach, we applied it to real‐world data sets and computed paths considering user constraints. The structuring of the point cloud into an octree approximation improves the point cloud processing and provides a structure for the empty space of the point cloud. It is also helpful to compute paths sufficiently accurate in their consideration of the spatial complexity. The entire process is automatic and able to deal with a large number of multi‐story indoor environments.  相似文献   

Improved water resource management for a highly complex environment using three-dimensional groundwater modelling     

Christian?MoeckEmail author  Annette?Affolter  Dirk?Radny  Horst?Dressmann  Adrian?Auckenthaler  Peter?Huggenberger  Mario?Schirmer 《Hydrogeology Journal》2018,26(1):133-146

A three-dimensional groundwater model was used to improve water resource management for a study area in north-west Switzerland, where drinking-water production is close to former landfills and industrial areas. To avoid drinking-water contamination, artificial groundwater recharge with surface water is used to create a hydraulic barrier between the contaminated sites and drinking-water extraction wells. The model was used for simulating existing and proposed water management strategies as a tool to ensure the utmost security for drinking water. A systematic evaluation of the flow direction between existing observation points using a developed three-point estimation method for a large number of scenarios was carried out. It is demonstrated that systematically applying the developed methodology helps to identify vulnerable locations which are sensitive to changing boundary conditions such as those arising from changes to artificial groundwater recharge rates. At these locations, additional investigations and protection are required. The presented integrated approach, using the groundwater flow direction between observation points, can be easily transferred to a variety of hydrological settings to systematically evaluate groundwater modelling scenarios.  相似文献   

Tourmaline Reference Materials for the In Situ Analysis of Oxygen and Lithium Isotope Ratio Compositions     

Michael Wiedenbeck  Robert B. Trumbull  Martin Rosner  Adrian Boyce  John H. Fournelle  Ian A. Franchi  Ralf Halama  Chris Harris  Jack H. Lacey  Horst Marschall  Anette Meixner  Andreas Pack  Philip A.E. Pogge von Strandmann  Michael J. Spicuzza  John W. Valley  Franziska D.H. Wilke 《Geostandards and Geoanalytical Research》2021,45(1):97-119

Three tourmaline reference materials sourced from the Harvard Mineralogical and Geological Museum (schorl 112566, dravite 108796 and elbaite 98144), which are already widely used for the calibration of in situ boron isotope measurements, are characterised here for their oxygen and lithium isotope compositions. Homogeneity tests by secondary ion mass spectrometry (SIMS) showed that at sub‐nanogram test portion masses, their ¹⁸O/¹⁶O and ⁷Li/⁶Li isotope ratios are constant within ± 0.27‰ and ± 2.2‰ (1s), respectively. The lithium mass fractions of the three materials vary over three orders of magnitude. SIMS homogeneity tests showed variations in ⁷Li/²⁸Si between 8% and 14% (1s), which provides a measure of the heterogeneity of the Li contents in these three materials. Here, we provide recommended values for δ¹⁸O, Δ’¹⁷O and δ⁷Li for the three Harvard tourmaline reference materials based on results from bulk mineral analyses from multiple, independent laboratories using laser‐ and stepwise fluorination gas mass spectrometry (for O), and solution multi‐collector inductively coupled plasma‐mass spectroscopy (for Li). These bulk data also allow us to assess the degree of inter‐laboratory bias that might be present in such data sets. This work also re‐evaluates the major element chemical composition of the materials by electron probe microanalysis and investigates these presence of a chemical matrix effect on SIMS instrumental mass fractionation with regard to δ¹⁸O determinations, which was found to be < 1.6‰ between these three materials. The final table presented here provides a summary of the isotope ratio values that we have determined for these three materials. Depending on their starting mass, either 128 or 512 splits have been produced of each material, assuring their availability for many years into the future.  相似文献   

Ichthyofauna in the upper Rhine River close to the city of Karlsruhe as determined by the analysis of fish impingement by cooling-water intakes of a power plant     

Frankie Thielen  Uwe Weibel  Jürgen Hirt  Marcel Münderle  Michael Marten  Horst Taraschewski  Bernd Sures 《Limnologica》2008,38(1):76-85

The fish fauna in the northern part of the upper river Rhine close to the city of Karlsruhe (Germany) was analyzed by collecting fish from the cooling-water intake of a power plant (impingement method) between 1989 and 2001. With this method a total of 36 fish species were recorded. The results were compared between the years as well as with other studies on the fish fauna in this area. Particularly with regard to the physical structure of the river bed and banks, the pre-technical situation of the river Rhine has not been restored. However, the number of fish species has been augmented since the 1970s mainly due to improvements in the water quality and almost all autochthonous fish species are present again. Altogether only three introduced fish species (Sander lucioperca L., Lepomis gibbosus L., and Carassius auratus gibelio were found in this study. Among the long-distance migrating species three freshwater spawners (Lampetra fluviatilis, Petromyzon marinus and Salmo trutta trutta) were detected in addition to the catadromous eel. The eudominant fish species varied between years, i.e. the European eel, Anguilla anguilla, was the eudominant species 1989, whereas this species occurred in much lower numbers during the subsequent sampling campaigns. This clearly indicates that the high dominance of eels is mainly caused by stocking activities in the upper Rhine. In the following years roach, Rutilus rutilus was the eudominant fish species. Overall a positive development of the fish fauna in the upper Rhine over the last 15 years could be observed in terms of fish populations as well as in terms of species richness.  相似文献   

Advancing Contaminant Mass Flux Analysis to Focus Remediation: The Three‐Compartment Model          下载免费PDF全文

John Horst  Scott Potter  Matthew Schnobrich  Nicklaus Welty  Ankit Gupta  Joseph Quinnan 《Ground Water Monitoring & Remediation》2017,37(4):15-22

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Groundwater Remediation in Low-Permeability Settings: The Evolving Spectrum of Proven and Potential     

John Horst  Craig Divine  Matthew Schnobrich  Ryan Oesterreich  Jonah Munholland 《Ground Water Monitoring & Remediation》2019,39(1):11-19

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