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61.
Methodological Aspects of the Tolerable Windows Approach   总被引:1,自引:1,他引:1  
The tolerable windows approach (TWA) allows the climate policyformulation process to be safeguarded in the following way. First,guardrails are defined in order to exclude intolerable climatechange impacts, on the one hand, and unacceptable socioeconomicconsequences of climate change mitigation measures, on the other.Second, a scientific analysis is conducted to investigate thefeatures of those emission paths that are compatible with theguardrail constraints. The fundamental methodology of the TWA isbest described in terms of the theory of differentialinclusions. This emerging mathematical theory already providesnumerical methods applicable as long as the underlying integratedassessment models are of limited complexity. In order to identifyemissions corridors, we propose a novel calculation schemeapplicable also for large-scale integrated assessment models.  相似文献   
62.
Understanding Anisotropy Computations   总被引:2,自引:0,他引:2  
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63.
64.
Symmetric planar central configurations of five bodies: Euler plus two   总被引:2,自引:0,他引:2  
We study planar central configurations of the five-body problem where three of the bodies are collinear, forming an Euler central configuration of the three-body problem, and the two other bodies together with the collinear configuration are in the same plane. The problem considered here assumes certain symmetries. From the three bodies in the collinear configuration, the two bodies at the extremities have equal masses and the third one is at the middle point between the two. The fourth and fifth bodies are placed in a symmetric way: either with respect to the line containing the three bodies, or with respect to the middle body in the collinear configuration, or with respect to the perpendicular bisector of the segment containing the three bodies. The possible stacked five-body central configurations satisfying these types of symmetries are: a rhombus with four masses at the vertices and a fifth mass in the center, and a trapezoid with four masses at the vertices and a fifth mass at the midpoint of one of the parallel sides.  相似文献   
65.
The Villalbeto de la Peña meteorite that fell in 2004 in Spain was originally classified as a moderately shocked L6 ordinary chondrite. The recognition of fragments within the Villalbeto de la Peña meteorite clearly bears consequences for the previous classification of the rock. The oxygen isotope data clearly show that an exotic eye‐catching, black, and plagioclase‐(maskelynite)‐rich clast is not of L chondrite heritage. Villalbeto de la Peña is, consequently, reclassified as a polymict chondritic breccia. The oxygen isotope data of the clast are more closely related to data for the winonaite Tierra Blanca and the anomalous silicate‐bearing iron meteorite LEW 86211 than to the ordinary chondrite groups. The REE‐pattern of the bulk inclusion indicates genetic similarities to those of differentiated rocks and their minerals (e.g., lunar anorthosites, eucritic, and winonaitic plagioclases) and points to an igneous origin. The An‐content of the plagioclase within the inclusion is increasing from the fragment/host meteorite boundary (approximately An10) toward the interior of the clast (approximately An52). This is accompanied by a successive compositionally controlled transformation of plagioclase into maskelynite by shock. As found for plagioclase, compositions of individual spinels enclosed in plagioclase (maskelynite) also vary from the border toward the interior of the inclusion. In addition, huge variations in oxygen isotope composition were found correlating with distance into the object. The chemical and isotopical profiles observed in the fragment indicate postaccretionary metamorphism under the presence of a volatile phase.  相似文献   
66.
Anin situ measurement of the lunar neutron density from 20 to 400 g cm?2 depth below the lunar surface was made by the Apollo 17 Lunar Neutron Probe Experiment (LNPE) using particle tracks produced by the10B (n,α)7Li reaction. Both the absolute magnitude and the depth profile of the neutron density are in good agreement with theoretical calculations by Lingenfelter, Canfield, and Hampel. However, relatively small deviations between experiment and theory in the effect of Cd absorption on the neutron density and in the relative149Sm to157Gd capture rates reported previously (Russet al., 1972) imply that the true lunar157Gd capture rate is about one half of that calculated theoretically.  相似文献   
67.
68.
New evidence for high-pressure, eclogite facies metamorphism in the crystalline basement of the Tisza Megaunit (southern Hungary) is reported. The retrogressed mafic eclogite forms a small lens in the orthogneiss and it was found in the borehole near Jánoshalma. The carbonated eclogite contains the peak metamorphic assemblage omphacite + garnet + phengite + kyanite + clinozoizite + rutile + K-feldspar + quartz. Omphacite (Xjd0.40–0.41Xdio0.52–0.53Xhd0.05Xaug1.55–2.85) occurs in the matrix and as inclusions in garnet (Xpy0.37–0.38Xgrs0.21–0.22Xalm0.39–0.40Xsps0–0.01Xadr0–0.01) and kyanite. Thermobarometry based on net-transfer reactions between garnet, omphacite, kyanite and phengite yields PT conditions of 710 ± 10 °C and 2.6 ± 0.75 GPa. Retrogression during decompression is manifested by formation of symplectites; the most typical are diopside + plagioclase after omphacite, corundum + spinel + plagioclase after kyanite and biotite + plagioclase after phengite. Carbonatization along the veins of the retrogressed eclogite was probably coeval with formation of these symplectites. At places where carbonate is absent the rock was completely hydrated and retrogressed down to the greenschist facies with the development of actinolite. Similar eclogites together with abundant orthogneisses occur mainly in the eastern parts of the Tisza Megaunit, suggesting the existence of an ancient (possibly Variscan) subduction/accretionary complex.  相似文献   
69.
 Research into the patterns of natural underground water effluents has been conducted in a small catchment basin (Wierzbanówka) that is representative of the Carpathian foothills. The aim of this study was to understand the long-term dynamics of the effluents and their responses to natural and artificial factors in order to estimate groundwater resources. High variability of the effluent patterns in the Carpathian foothills is a result of precipitation fluctuations, low ground retention capacity, a low rate of absorption in the flysch rock formation areas, and of the Quaternary covers. In addition, the dominance of agricultural land use, low forest coverage, and poor hydrological management are the main causes of this variability. Any local increase in underground water resources would only be possible if forests were planted on some of the agricultural land and changes were made to water management. Received: 16 August 1999 · Accepted: 12 January 2000  相似文献   
70.
Karlický  Marian  Kotrč  Pavel  Kupryakov  Yurij A. 《Solar physics》2001,199(1):145-155
Large Doppler velocities with unique, almost regular elliptical features were observed in the H spectra of the May 15, 2000 eruptive prominence. These features were interpreted in the frame of axially symmetric models of the eruptive prominence. The rotational (7–60 km s–1), expansion (30–44 km s–1), axial (3–19 km s–1), and global (66–160 km s–1) prominence plasma velocities were derived. The plasma velocity patterns were compared with the observed helical structures of the H prominence. The velocities of selected H blobs in the image plane were determined. The axially symmetric detwisting process of the magnetic flux rope of the eruptive prominence was recognized.  相似文献   
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