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51.
Accurately mapped locations within multi-unit properties are useful for several organizations in today's society. Published work on geocoding methods either require detailed location reference data or does not apply to multi-unit buildings. In this research, a generalizable method is realized to map apartment addresses to their explicit locations without access to indoor location reference data based on publicly available address- and geospatial-building information. The performance of this approach is measured by conducting a comparative study between a linear interpolation baseline and gradient-boosted decision trees model. The proposed method can successfully geocode addresses across different building shapes and sizes. Furthermore, the model significantly outperforms the baseline in terms of positional accuracy proving the feasibility of approximating apartment locations by their address- and geospatial-building information. 相似文献
52.
The compositional variation of accessory monazite in ore bearing micaschists from the Schellgaden mining district, Tauern Window, Eastern Alps, was studied by means of the electron microprobe. In ore-rich domains monazite yields unusually high sulfur contents (up to 2.5?wt.% SO3), which enter the monazite structure together with Ca and Sr as ??anhydrite-celestine?? component replacing P and REEs. The exchange reaction is S6++ (Ca, Sr)2+ = REE3++ P5+. Sulfur-rich monazite is intergrown with anglesite, pyromorphite or galena and shows oscillatory zoning indicating growth from S-bearing fluids. This type of S-enriched monazite yields very high common lead contents (up to 0.5?wt.% PbO) and unrealistic high apparent Th-U-total Pb single dates (> 1?Ga). However, S-enriched monazite grains provide a flat trendline in the Th* vs. Pb isochron diagram similar to the trendline defined through low-S, and low-Pb monazite crystals (0.1?C1?wt.% SO3, < 0.05?wt.% PbO), which were observed in ore-poor parts of micaschists. Results from this study imply an Alpine rather than a pre-Alpine formation age for monazite and a strong S-rich fluid activity during the Alpine orogeny. Apart from this geological aspect, the current study also shows that the detection of sulfur in monazite may serve as a warning for a possible presence of common Pb. 相似文献
53.
Vanja Bi?evac Erwin Krenn Dra?en Balen Fritz Finger Kadosa Balogh 《Mineralogy and Petrology》2011,102(1-4):163-180
Granitic pebbles occurring in the Permotriassic metasedimentary sequence of eastern Papuk, Slavonian Mountains, Croatia, were recognized to represent a coherent group of felsic, muscovite-albite metagranites. Fabrics, modal compositions and geochemical data imply that the rocks are derivatives of S-type granites formed through a combination of igneous and subsequent metasomatic processes. A Variscan formation age is demonstrated by K-Ar dating on coarse muscovite (range of 329?C317?Ma) as well as by electron microprobe based Th-U-Pb monazite dating (338?±?15?Ma). Additionally to the Variscan metasomatic processes of albitization and greisenisation, which led to an almost complete replacement of K-feldspar and biotite by albite and coarse muscovite, pebbles were affected by a younger phase of alteration resulting in the formation of a fine-grained sericitic matrix. The fine sericite yields K-Ar ages of 91?C83?Ma. A substantial reheating of the rocks during the Cretaceous is also indicated by the growth of new monazite dated at 106?±?10?Ma. Yttrium-contents of the Cretaceous monazite from the granite pebbles (0.3?C0.9?wt% Y2O3) are compatible with metamorphic temperatures of ~350?C400°C. These data confirm recent concepts according to which large parts of the Slavonian Mountains received a pervasive Cretaceous low-T regional metamorphic overprint. Furthermore, the pebbles provide useful information on the nature of the eroded Variscan crust of the Tisia Terrain, which has obviously contained considerable amounts of evolved high-level S-type granites modified through albitization and greisenization. 相似文献
54.
Erwin Sedlmayr 《Astrophysics and Space Science》1997,251(1-2):103-114
55.
YANG Yibo FANG Xiaomin LI Minghui APPEL Erwin ZHANG Weilin LIU Xiaoming 《《地质学报》英文版》2014,88(Z1):168-169
正Uranium(U)provides especially useful information for reconstructing paleoredox conditions due to its unique geochemical properties and behavior in supergene environments.The proxy potential under suboxic-oxic 相似文献
56.
Microcrystals (1–15 μm) of unusual monazite (La) with 41–47 mol% cheralite [ThCa(PO4)2] component and a strong negative Ce anomaly are described from a metadiorite from the SW Slavonian Mountains, Psunj, Croatia. The dioritic host rock still shows a relictic igneous fabric on macroscopic scale. However, metamorphic reaction textures can be recognized in thin section. These include partial recrystallization of igneous plagioclase to albite coupled with the formation of epidote. Furthermore, partial replacement of igneous hornblende by a fine-grained orthoamphibole-chamosite-epidote paragenesis can be observed and replacement of ilmenite by titanite. The compositions of the metamorphic minerals indicate upper greenschist facies conditions (460–500 °C according to two-feldspar geothermometry) under a high oxygen fugacity. Microstructures show that the monazite crystals belong to the metamorphic paragenesis and formed at the expense of magmatic allanite. Their negative Ce anomalies reflect the oxidizing conditions of metamorphism. Application of the xenotime in monazite solvus geothermometer provides unrealistically high temperatures of ~500–660 °C which disagree with the greenschist facies metamorphic paragenesis. We interpret that the presence of cheralite has a profound effect on the nature of the monazite-xenotime solvus curve and hence the existing calibrations of this geothermometer may be generally unsuitable for cheralite-rich monazite. An important geological result is that the Th-U-total Pb ages of the monazite grains are uniformingly Upper Cretaceous. Our data thus suggest that the imprint of the Alpine orogeny on the Slavonian Mountains was stronger than presumed until now. 相似文献
57.
Tingping Ouyang Erwin Appel Guodong Jia Ningsheng Huang Zhaoyu Zhu 《Environmental Earth Sciences》2013,68(6):1609-1617
Magnetic parameters have been widely used as a rapid, cost-effective, and non-destructive method. To assess whether their magnetic properties reflect the development history in the Pearl River Delta, three sediment cores collected from South China coastal waters were selected for magnetic research. The results indicate that the predominant ferrimagnetic mineral is magnetite, with an additional smaller amount of surprisingly high-coercive greigite. Fine-grained superparamagnetic and single-domain particles of magnetite and the relative contribution of greigite are increased when the total concentration of ferrimagnetic minerals is higher. Three well-known stages of the Chinese history, i.e., iron smelting, cultural revolution, and the latest phase of opening and reforming were identified in the vertical variation of magnetic concentration parameters. Although the record of the three cores is not completely consistent, the results point out that magnetic concentration parameters can reflect the development and pollution history in surrounding coastal areas. 相似文献
58.
Jörg M. Colberg Frazer Pearce Caroline Foster Erwin Platen Riccardo Brunino Mark Neyrinck Spyros Basilakos Anthony Fairall Hume Feldman Stefan Gottlöber Oliver Hahn Fiona Hoyle Volker Müller Lorne Nelson Manolis Plionis Cristiano Porciani Sergei Shandarin Michael S. Vogeley Rien van de Weygaert 《Monthly notices of the Royal Astronomical Society》2008,387(2):933-944
Despite a history that dates back at least a quarter of a century, studies of voids in the large-scale structure of the Universe are bedevilled by a major problem: there exist a large number of quite different void-finding algorithms, a fact that has so far got in the way of groups comparing their results without worrying about whether such a comparison in fact makes sense. Because of the recent increased interest in voids, both in very large galaxy surveys and in detailed simulations of cosmic structure formation, this situation is very unfortunate. We here present the first systematic comparison study of 13 different void finders constructed using particles, haloes, and semi-analytical model galaxies extracted from a subvolume of the Millennium simulation. This study includes many groups that have studied voids over the past decade. We show their results and discuss their differences and agreements. As it turns out, the basic results of the various methods agree very well with each other in that they all locate a major void near the centre of our volume. Voids have very underdense centres, reaching below 10 per cent of the mean cosmic density. In addition, those void finders that allow for void galaxies show that those galaxies follow similar trends. For example, the overdensity of void galaxies brighter than m B =−20 is found to be smaller than about −0.8 by all our void finding algorithms. 相似文献
59.
Erwin Platen Rien van de Weygaert Bernard J. T. Jones 《Monthly notices of the Royal Astronomical Society》2008,387(1):128-136
We investigate the shapes and mutual alignment of voids in the large-scale matter distribution of a Λ cold dark matter (ΛCDM) cosmology simulation. The voids are identified using the novel watershed void finder (WVF) technique. The identified voids are quite non-spherical and slightly prolate, with axis ratios in the order of c : b : a ≈ 0.5 : 0.7 : 1 . Their orientations are strongly correlated with significant alignments spanning scales >30 h −1 Mpc .
We also find an intimate link between the cosmic tidal field and the void orientations. Over a very wide range of scales we find a coherent and strong alignment of the voids with the tidal field computed from the smoothed density distribution. This orientation–tide alignment remains significant on scales exceeding twice the typical void size, which shows that the long-range external field is responsible for the alignment of the voids. This confirms the view that the large-scale tidal force field is the main agent for the large-scale spatial organization of the cosmic web. 相似文献
We also find an intimate link between the cosmic tidal field and the void orientations. Over a very wide range of scales we find a coherent and strong alignment of the voids with the tidal field computed from the smoothed density distribution. This orientation–tide alignment remains significant on scales exceeding twice the typical void size, which shows that the long-range external field is responsible for the alignment of the voids. This confirms the view that the large-scale tidal force field is the main agent for the large-scale spatial organization of the cosmic web. 相似文献
60.
粉煤灰经工厂废气排放进入大气,对人类健康和生态系统都造成了无法弥补的破坏.本文选取具有高空间分辨率优势的树叶作为收集粉煤灰的载体,对临汾市大气中可吸入颗粒物进行磁学参数和重金属含量监测.结果表明,磁化率最大值出现在工厂污染源附近,磁化率空间分布呈现随污染源距离增加而降低的趋势.工业区收集到的磁性颗粒以低矫顽力、粗粒度的磁铁矿为主.夏季磁性矿物来源单一,主要为人为影响.冬季大气中悬浮的磁性颗粒有部分来自于西北风/北风的自然尘降.同一采样点磁化率随时间变化特征表明,树叶的磁学性质可以灵敏和有效地反映较短时期内大气污染的现状.统计分析表明磁化率和重金属元素(铁,铬,镍,铜,铅,钴)之间存在显著相关性.污染负荷指数用于评估研究区域内重金属各元素综合污染的程度.结果显示,在废弃的旧工业区附近无大气污染指示,但在运营中的工厂集中的地区,大气均受到严重污染.污染负荷指数与表征磁性矿物含量的磁化率呈相关性(r2=0.66),因此树叶的磁性参数可以作为大气重金属污染的替代指标. 相似文献