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A modified normalized input-output minimization (Mod-NIOM) method for seismic wave propagation modeling

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Earthquake Engineering and Engineering Vibration 2010年第4期9卷 481-491页

作者： Santa Man Shrestha Hideji Kawakami Eric Augustus Tingatinga Hidenori Mogi Department of Civil and Environmental Engineering Saitama University geosphere research institute Saitama University institute of Civil Engineering University of the Philippines Diliman

A new method for wave propagation modeling is introduced in this paper. By using the constraint optimization （Lagrange multiplier） method, the sum of weighted squared Fourier amplitudes is minimized when subjected to a constraint. The sum of the maximum amplitudes obtained from all output models is normalized to unity and is taken as a constraint. In this method, all the actual time histories are considered as outputs and dealt with equally. Independently of the combinations of time histories （or the first time history selected） during the analysis, the method captures the relationship of actual time histories by showing clear peaks. This paper describes the formulation of the models and illustrates the advantage of this method over the normalized input-output minimization （NIOM） method. The Mod-NIOM is then used to analyze the time histories of the Hyogoken-nanbu earthquake recorded at the Port Island vertical array site in Kobe, which suffered from liquefaction caused by the strong motions during the main shock. This method showed good correlations between the observed time histories at the site even though the surface time history was greatly modified by the liquefaction.

关键词： wave propagation constraint optimization S-wave velocity liquefaction amplification vertical array Hyogoken-nanbu earthquake

Geochemical Stratigraphy and Microvertebrate Assemblage Sequences across the Silurian/Devonian Transition in South China

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Acta Geologica Sinica(English Edition) 2011年第2期85卷 340-353页

作者： ZHAO Wenjin WANG Nianzhong ZHU Min Ulrich MANN Ulrich HERTEN Andreas LǖKE Key Laboratory of Evolutionary Systematics of Vertebrates Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China institute of Chemistry and Dynamics of the geosphere ICG-4 Research Center Juelich GmbH D-52425 Juelich Germany

Carbon isotope （δ13Corg） analyses of non-marine clastic rocks and neritic carbonates and black shales spanning the Silurian/Devonian transition are compared from two richly fossiliferous sequences in Qujing of East Yunnan and Zoige of Sichuan, South China. The two sections, Xishancun and Putonggou sections in South China, reveal positive δ13Corg shifts happening in the Upper Pridoli and Lower Devonian and reaching peak values as heavy as -25.2‰ （Xishancun） and -19.9‰（Putonggou） in the lowermost Lochkovian following the first occurrence of the thelodont Parathelodus and the conodont Icriodus woschmidti woschmidti （only in Putonggou Section and together with Protathyris-Lanceomyonia brachiopod fauna）. These results replicate a globally known positive shift in δ13Corg from the uppermost Silurian to the lowermost Devonian. The δ13Corg variations across the Silurian/Devonian Boundary （SDB） at the two sections in South China exhibit a shift in carbon isotopic composition similar to the detailed SDB curves from the borehole Klonk-1 drilled at top of the Klonk Global Standard Stratotype-Section and Point （GSSP） in the Prague Basin, Czech Republic. In addition, four microvertebrate assemblages, including the Liaojiaoshan, Xishancun, Yanglugou and Xiaputonggou assemblages, are recognized from the Silurian/Devonian transition exposed in the Xishancun and Putonggou sections, respectively. The results from both carbon isotope stratigraphy and microvertebrate assemblage sequences suggest that the SDB in South China is located at the base of the Xishancun Formation （between sample QX-20 and sample QX-21） in the Xishancun Section and the lower part of the Xiaputonggou Formation （between sample ZP-09 and sample ZP-10） in the Putonggou Section. The isotopic trend for organic carbon together with the changes of microvertebrate remains across the SDB can offer an approach to a potential correlation of the SDB from different sedimentary facies, which help to correlate the marine with no

关键词： Carbon isotope stratigraphy microvertebrate assemblages Silurian-Devonian Boundary marine and non- marine stratigraphic correlation South China

Holocene climate change in the Central Tibetan Plateau inferred by lacustrine sediment geochemical records

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Science China Earth Sciences 2007年第10期50卷 1548-1555页

作者： Andreas LüCKE Bernd WüNNEMANN institute of Chemistry and Dynamics of the geosphere V: Sedimentary Systems Research Centre Jülich D-52425 Jülich Ger- many Interdisciplinary Centre Ecosystem Dynamics in Central Asia Freie Universitaet Berlin 12249 Berlin Germany

Multi-proxies of lacustrine sediments, such as total carbon (TC), total organic carbon (TOC), total inorganic carbon (TIC), total nitrogen (TN), total sulfur (TS), hydrogen index (HI), oxygen index (OI) and stable carbon isotopic composition of organic matter (δ^(13)C_(org)), were analyzed using a 7.3 m core from Zige Tangco. The source of the organic matter in the sediment was mainly from autochthonous phyto-plankton, therefore the significances of proxies can be interpreted as that high TOC, TOC/TS, HI and δ^(13)C_(org) values, low TC, TIC values corresponded to warm and wet climatic condition, and vice versa. The process of climatic development in the Zige Tangco region was hence recovered. During the early and Mid-Holocene, the climate was warm and wet and intensive cold events occurred during the periods of 8600 to 8400 cal a BP and 7400 to 7000 cal a BP. In the second half of Holocene, the climate became cold and dry gradually. The palaeoclimatic process during Holocene in Zige Tangco region matched well with that in Co Ngoin region which is ca 40 km to the south-east. Therefore this palaeoclimatic process represents the Holocene climatic feature in the Central Tibetan Plateau which has the same pattern in the Northern Tibetan Plateau, but the time and duration of some climatic events might be different. We can conclude that in Holocene solar insolation controlled the climatic pattern on the central Tibetan Plateau.

关键词： lacustrine sediment hydrogen index (HI) stable carbon isotopic composition (δ^(13)C_(org)) palaeoclimate Central Tibetan Plateau

Adopting the margin of stability for space–time landslide prediction–A data-driven approach for generating spatial dynamic thresholds

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Geoscience Frontiers 2024年第5期15卷 75-92页

作者： Stefan Steger Mateo Moreno Alice Crespi Stefano Luigi Gariano Maria Teresa Brunetti Massimo Melillo Silvia Peruccacci Francesco Marra Lotte de Vugt Thomas Zieher Martin Rutzinger Volkmar Mair Massimiliano Pittore geosphere Austria ViennaAustria Center for Climate Change and Transformation Eurac ResearchBolzanoItaly Faculty of Geo-information Science and Earth Observation(ITC) University of TwenteEnschedethe Netherlands research institute for Geo-Hydrological Protection National Research Council(CNR-IRPI)PerugiaItaly Department of Geosciences University of PaduaPaduaItaly institute of Atmospheric Sciences and Climate National Research Council(CNR-ISAC)BolognaItaly Department of Geography University of InnsbruckInnsbruckAustria Department of Natural Hazards Austrian Research Centre for Forests(BFW)InnsbruckAustria Office for Geology and Building Materials Testing Autonomous Province of Bolzano-South TyrolCardanoItaly

Shallow landslide initiation typically results from an interplay of dynamic triggering and preparatory conditions along with static predisposition *** data-driven methods for assessing landslide susceptibility or for establishing rainfall-triggering thresholds are prevalent,integrating spatiotemporal information for dynamic large-area landslide prediction remains a *** main aim of this research is to generate a dynamic spatial landslide initiation model that operates at a daily scale and explicitly counteracts potential errors in the available landslide *** previous studies focusing on space–time landslide modelling,it places a strong emphasis on reducing the propagation of landslide data errors into the modelling results,while ensuring interpretable *** introduces also other noteworthy innovations,such as visualizing the final predictions as dynamic spatial thresholds linked to true positive rates and false alarm rates and by using animations for highlighting its application potential for hindcasting and *** initial step involves the creation of a spatio-temporally representative sample of landslide presence and absence observations for the study area of South Tyrol,Italy(7400 km2)within well-investigated *** setup entails integrating landslide controls that operate on various temporal scales through a binomial Generalized Additive Mixed *** relationships are then interpreted based on variable importance and partial effect plots,while predictive performance is evaluated through various crossvalidation *** and user-defined probability cutpoints are used to establish quantitative thresholds that reflect both,the true positive rate(correctly predicted landslides)and the false positive rate(precipitation periods misclassified as landslide-inducing conditions).The resulting dynamic maps directly visualize landslide threshold *** model demonstrates high predictive performanc

关键词： Early warning Space-time model Rainfall thresholds Landslide susceptibility,Generalized Additive Mixed Model Forecasting

New urban map of Eurasia using MODIS and multi-source geospatial data

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Geo-Spatial Information Science 2017年第1期20卷 29-38页

作者： Bayan Alsaaideh Ryutaro Tateishi Dong Xuan Phong Nguyen Thanh Hoan Ahmad Al-Hanbali Bai Xiulian Center for Environmental Remote Sensing(CEReS) Chiba UniversityChibaJapan COPRONA Inc.International Consulting Company Vung TauVietnam institute of Geography Vietnamese Academy of Science and Technology(VAST)HanoiVietnam geosphere environmental technology corp. tokyoJapan

Urban areas are of paramount significance to both the individuals and communities at local and regional ***,the rapid growth of urban areas exerts effects on climate,biodiversity,hydrology,and natural ecosystems ***,regular and up-to-date information related to urban extent is necessary to monitor the impacts of urban areas at local,regional,and potentially global *** study presents a new urban map of Eurasia at 500 m resolution using multi-source geospatial data,including Moderate Resolution Imaging Spectroradiometer(MODIS)data of 2013,population density of 2012,the Defense Meteorological Satellite Program’s Operational Linescan System(DMSP-OLS)nighttime lights of 2012,and constructed Impervious Surface Area(ISA)data of *** Eurasian urban map was created using the threshold method for these data,combined with references of fine resolution Landsat and Google Earth *** resultant map was compared with nine global urban maps and was validated using random sampling *** of the accuracy assessment showed high overall accuracy of the new urban map of 94%.This urban map is one product of the 20 land cover classes of the next version of Global Land Cover by National Mapping Organizations.

关键词： Urban area mapping population density MODIS data integration accuracy assessment eurasia

Seismicity,structure and tectonics in the Arctic region

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Geoscience Frontiers 2015年第5期6卷 665-677页

作者： Masaki Kanao Vladimir D.Suvorov Shigeru Toda Seiji Tsuboi National institute of Polar research.research Organization of Information and Systems Trofimuk institute of Petroleum Geology and Geophysics of Siberian Branch Russian Academy of Sciences Department of Earth Sciences Faculty of EducationAichi University of Education institute for research on Earth Evolution Japan Agency for Marine-Earth Science and Technology

The "Arctic" region,where the North Pole occupies the center of the Arctic Ocean,has been affecting the environmental variation of the Earth from geological time to the ***,the seismic activities in the area are not adequately ***,by conducting long term monitoring of seismic phenomenon as sustainable parameters,our understanding of both the tectonic evolution of the Earth and the dynamic interaction between the cryosphere and geosphere in surface layers of the Earth will *** this paper,the association of the seismicity and structure of the Arctic region,particularly focused on Eurasian continent and surrounding oceans,and its relationship with regional evolution during the Earth’s history is *** target areas cover representative tectonic provinces in the Eurasian Arctic,such as the wide area of Siberia,Baikal Rift *** East Russia,Arctic Ocean together with Greenland and Northern *** on discussion including characteristics of seismicity,heterogeneous structure of the crust and upper mantle,tectonic history and recent dynamic features of the Earth’s surface in the Arctic are summarized.

关键词： Arctic region Seismicity Tectonics Earth’s structu

Doped GaSe crystals for laser frequency conversion

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Light(Science & Applications) 2015年第1期4卷 47-58页

作者： Jin Guo Ji-Jiang Xie Dian-Jun Li Gui-Long Yang Fei Chen Chun-Rui Wang Lai-Ming Zhang Yury M Andreev Konstantin A Kokh Gregory V Lanskii Valery A Svetlichnyi State Key Laboratory of Laser Interaction with Matter Changchun Institute of OpticsFine Mechanics and PhysicsCASChangchun 130033China Innovation Laboratory of Electro-Optical Countermeasures Technology Changchun Institute of OpticsFine Mechanics and PhysicsCASChangchun 130033China Laboratory of geosphereBiosphere Interactions Institute of Monitoring of Climatic and Ecological SystemsSB RASTomsk 634055Russia Laboratory of Advanced Materials and Technologies Siberian Physical-Technical Institute of Tomsk State UniversityTomsk 634050Russia Crystal Growth Laboratory Institute of Geology and MineralogySB RASNovosibirsk 630090Russia Novosibirsk State University Novosibirsk 630090Russia

In this review,we introduce the current state of the art of the growth technology of pure,lightly doped,and heavily doped(solid solution)nonlinear gallium selenide(GaSe)crystals that are able to generate broadband emission from the near infrared(IR)(0.8 mm)through the mid-and far-IR(terahertz(THz))ranges and further into the millimeter wave(5.64 mm)*** the first time,we show that appropriate doping is an efficient method controlling a range of the physical properties of GaSe crystals that are responsible for frequency conversion efficiency and exploitation *** appropriate doping,uniform crystals grown by a modified technology with heat field rotation possess up to 3 times lower absorption coefficient in the main transparency window and THz ***,doping provides the following benefits:raises by up to 5 times the optical damage threshold;almost eliminates two-photon absorption;allows for dispersion control in the THz range independent of the mid-IR dispersion;and enables crystal processing in arbitrary directions due to the strengthened ***,doped GaSe demonstrated better usefulness for processing compared with GaSe grown by the conventional technology and up to 15 times higher frequency conversion efficiency.

关键词： frequency conversion GaSe solid solution crystal THz

Paleoclimate Modelling at the institute of Atmospheric Physics, Chinese Academy of Sciences

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Advances in Atmospheric Sciences 2006年第6期23卷 1040-1049页

作者：姜大膀张仲石 Nansen-Zhu International research Centre Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029

Paleoclimate modelling is one of the core topics in the Past Global Changes project under the International geosphere-Biosphere Programme and has received much attention worldwide in recent decades. Here we summarize the research on the Paleoclimate modeling, including the Holocene, Last Glacial Maximum, and pre-Quaternary climate intervals or events performed at the institute of Atmospheric Physics under the Chinese Academy of Sciences （IAP/CAS） for over one decade. As an attempt to review these academic activities, we emphasize that vegetation and ocean feedbacks can amplify East Asian climate response to the Earth＇s orbital parameters and atmospheric CO2 concentration at the mid-Holocene. At the Last Glacial Maximum, additional cooling in interior China is caused by the feedback effects of East Asian vegetation and the ice sheet over the Tibetan Plateau, and the regional climate model RegCM2 generally reduces data-model discrepancies in East Asia. The simulated mid-Pliocene climate is characterized by warmer and drier conditions as well as significantly weakened summer and winter monsoon systems in interior China. On a tectonic timescale, both the Tibetan Plateau uplift and the Paratethys Sea retreat play important roles in the formation of East Asian monsoon-dominant environmental pattern during the Cenozoic.

关键词： Paleoclimate modelling mid-Holocene Last Glacial Maximum mid-Pliocene Cenozoic

Composition of substituents on pyrrole ring of high-carbon-number geoporphyrins and its dealkylation

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Chinese Science Bulletin 1999年第3期44卷 267-269页

作者： ZHANG Chunming and LIN Renzi Geochemistry research Center, Jianghan Petroleum institute, Jingzhou 434102, China Department of Geoscience, University of Petroleum , Beijing 100083, China Geochemistry research Center Jianghan Petroleum Institute Jingzhou China Department of Geoscience University of Petroleum Beijing China

Geoporphyrins, isolated from source rock, were analyzed on electron ionization mass spectrometry （EIMS） and Tandem mass spectrometry （MS/MS）. The spectrum of ElMS shows that the geoporphyrins are mainly composed of two types: DPEP and eito. Most of the porphyrin carbon numbers are greater than C32. The daughter spectra of the molecular ions (C34-36DPEPs) display the loss of methyl and ethyl groups, which indicate there are ethyl and propyl groups in the mother ions. The average condensed structural formulae, derived from the data of the spectra on MS/MS, have clearly shown the composition of the substituents on the porphyrin pyrrole ring, and the regular changes of the substituents reveal the characteristics of the dealkylation of the porphyrins in the geosphere.

关键词： Tandem mass spectrometry geoporphyrins condensed structural formula dealkylation.