The alignment between the distribution of satellites and the orientation of their central galaxy   总被引：1，自引：0，他引：1  

Xiaohu Yang  Frank C. van den Bosch  H. J. Mo  Shude Mao  Xi Kang  Simone M. Weinmann  Yicheng Guo  Y. P. Jing 《Monthly notices of the Royal Astronomical Society》2006,369(3):1293-1302

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The impact of cooling and feedback on disc galaxies     

Frank C. van den Bosch 《Monthly notices of the Royal Astronomical Society》2002,332(2):456-472

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Populating dark matter haloes with galaxies: comparing the 2dFGRS with mock galaxy redshift surveys     

Xiaohu Yang  H. J. Mo  Y. P. Jing  Frank C. van den Bosch  YaoQuan Chu 《Monthly notices of the Royal Astronomical Society》2004,350(4):1153-1173

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Fuzzy Logic Determination of Lithologies from Well Log Data: Application to the KTB Project Data set (Germany)     

David Bosch  Juanjo Ledo  Pilar Queralt 《Surveys in Geophysics》2013,34(4):413-439

Fuzzy logic has been used for lithology prediction with remarkable success. Several techniques such as fuzzy clustering or linguistic reasoning have proven to be useful for lithofacies determination. In this paper, a fuzzy inference methodology has been implemented as a MATLAB routine and applied for the first time to well log data from the German Continental Deep Drilling Program (KTB). The training of the fuzzy inference system is based on the analysis of the multi-class Matthews correlation coefficient computed for the classification matrix. For this particular data set, we have found that the best suited membership function type is the piecewise linear interpolation of the normalized histograms; that the best combination operator for obtaining the final lithology degrees of membership is the fuzzy gamma operator; and that all the available properties are relevant in the classification process. Results show that this fuzzy logic-based method is suited for rapidly and reasonably suggesting a lithology column from well log data, neatly identifying the main units and in some cases refining the classification, which can lead to a better interpretation. We have tested the trained system with synthetic data generated from property value distributions of the training data set to find that the differences in data distributions between both wells are significant enough to misdirect the inference process. However, a cross-validation analysis has revealed that, even with differences between data distributions and missing lithologies in the training data set, this fuzzy logic inference system is able to output a coherent classification.  相似文献   

How basin model results enable the study of multi-layer aquifer response to pumping: the Paris Basin, France     

Camille Contoux  Sophie Violette  Raffaella Vivona  Patrick Goblet  Delphine Patriarche 《Hydrogeology Journal》2013,21(3):545-557

The Albian aquifer of the Paris Basin (France) has been exploited since 1841 and shows drastic drawdown. A three-dimensional (3D) groundwater flow model is used to study the hydrodynamic response of the multi-layered aquifers to pumping activity in the Albian, at basin scale over 167 years. This 3D flow model uses geometry and hydrodynamic parameter distributions that are inherited from a genetic approach through basin modelling, the basin model creating a geometric pattern of hydrodynamic properties constrained by geological history. The paper aims to promote the use of the basin model approach (long time scale, 248 Ma) for the study of deep-aquifer response to anthropogenic perturbation (short time scale, 167 years) in situations for which hydrodynamic data are scarce but geological data are numerous. The results show that parameter distribution is insufficient to reproduce the Albian aquifer behaviour, notably highlighting a different meaning of the specific storage coefficient between basin modelling and groundwater-flow modelling. Dividing the storage coefficient by 100 and including available transmissivity data significantly improved the model/data comparison. The potential impact on a deep aquitard is then discussed. This study sheds light on the advantages and limitations of the basin model approach for groundwater-flow modelling in 3D.  相似文献   

Recharge estimation of a small karstic aquifer in a semiarid Mediterranean region (southeastern Spain) using a hydrological model   总被引：1，自引：0，他引：1  

I. Touhami  J. M. Andreu  E. Chirino  J. R. Sánchez  H. Moutahir  A. Pulido‐Bosch  P. Martínez‐Santos  J. Bellot 《水文研究》2013,27(2):165-174

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Triaxial orbit based galaxy models with an application to the (apparent) decoupled core galaxy NGC 4365     

R. C. E. van den Bosch  G. van de Ven †  E. K. Verolme  M. Cappellari  P. T. de Zeeuw 《Monthly notices of the Royal Astronomical Society》2008,385(2):647-666

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The importance of satellite quenching for the build-up of the red sequence of present-day galaxies     

Frank C. van den Bosch  Daniel Aquino  Xiaohu Yang  H. J. Mo  Anna Pasquali  Daniel H. McIntosh  Simone M. Weinmann  Xi Kang 《Monthly notices of the Royal Astronomical Society》2008,387(1):79-91

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Unraveling the patterns of late Holocene debris-flow activity on a cone in the Swiss Alps: Chronology, environment and implications for the future     

Markus Stoffel  Delphine Conus  Michael A. Grichting  Igor Livre  Gilles Maître 《Global and Planetary Change》2008,60(3-4):222-234

Debris-flow activity on the forested cone of the Ritigraben torrent (Valais, Swiss Alps) was assessed from growth disturbances in century-old trees, providing an unusually complete record of past events and deposition of material. The study of 2246 tree-ring sequences sampled from 1102 Larix decidua Mill., Picea abies (L.) Karst. and Pinus cembra ssp. sibirica trees allowed reconstruction of 123 events since AD 1566. Geomorphic mapping permitted identification of 769 features related to past debris-flow activity on the intermediate cone. The features inventoried in the study area covering 32 ha included 291 lobes, 465 levées and 13 well-developed debris-flow channels. Based on tree-ring records of disturbed trees growing in or next to the deposits, almost 86% of the lobes identified on the present-day surface could be dated. A majority of the dated material was deposited over the last century. Signs of pre-20th century events are often recognizable in the tree-ring record of survivor trees, but the material that caused the growth anomaly in trees has been completely overridden or eroded by more recent debris-flow activity.Tree-ring records suggest that cool summers with frequent snowfalls at higher elevations regularly prevented the release of debris flows between the 1570s and 1860s; the warming trend combined with greater precipitation totals in summer and autumn between 1864 and 1895 provided conditions that were increasingly favorable for releasing events from the source zone. Enhanced debris-flow activity continued well into the 20th century and reconstructions show a clustering of events in the period 1916–1935 when warm–wet conditions prevailed during summer in the Swiss Alps. In contrast, very low activity is observed for the last 10-yr period (1996–2005) with only one debris-flow event recorded on August 27, 2002. Since sediment availability is not a limiting factor, this temporal absence of debris-flow activity is due to an absence of triggering events, which not only shifted from June and July to August and September over the 20th century, but also seemed to be initiated primarily by persistent precipitation rather than summer thunderstorms. From the reconstructions, based on RCM simulations, there are indications that debris-flow frequencies might continue to decrease in the future, as precipitation events are projected to occur less frequently in summer but become more common in spring or autumn.  相似文献   

Reconstruction of Tsunami Inland Propagation on December 26, 2004 in Banda Aceh, Indonesia, through Field Investigations     

Franck Lavigne  Raphaël Paris  Delphine Grancher  Patrick Wassmer  Daniel Brunstein  Franck Vautier  Frédéric Leone  François Flohic  Benjamin De Coster  Taufik Gunawan  Christopher Gomez  Anggri Setiawan  Rino Cahyadi  Fachrizal 《Pure and Applied Geophysics》2009,166(1-2):259-281

This paper presents the results from an extensive field data collection effort following the December 26, 2004 earthquake and tsunami in Banda Aceh, Sumatra. The data were collected under the auspices of TSUNARISQUE, a joint French-Indonesian program dedicated to tsunami research and hazard mitigation, which has been active since before the 2004 event. In total, data from three months of field investigations are presented, which detail important aspects of the tsunami inundation dynamics in Banda Aceh. These include measurements of runup, tsunami wave heights, flow depths, flow directions, event chronology and building damage patterns. The result is a series of detailed inundation maps of the northern and western coasts of Sumatra including Banda Aceh and Lhok Nga. Among the more important findings, we obtained consistent accounts that approximately ten separate waves affected the region after the earthquake; this indicates a high-frequency component of the tsunami wave energy in the extreme near-field. The largest tsunami wave heights were on the order of 35 m with a maximum runup height of 51 m. This value is the highest runup value measured in human history for a seismically generated tsunami. In addition, our field investigations show a significant discontinuity in the tsunami wave heights and flow depths along a line approximately 3 km inland, which the authors interpret to be the location of the collapse of the main tsunami bore caused by sudden energy dissipation. The propagating bore looked like a breaking wave from the landward side although it has distinct characteristics. Patterns of building damage are related to the location of the propagating bore with overall less damage to buildings beyond the line where the bore collapsed. This data set was built to be of use to the tsunami community for the purposes of calibrating and improving existing tsunami inundation models, especially in the analysis of extreme near-field events.  相似文献