朝鲜中生代构造   总被引：1，自引：0，他引：1  

金贞焕 《地球学报》1994,15(Z1):32-44

朝鲜中生代构造作用以多旋回的克拉通内变形为特，其中包括：a)韧性或脆必剪切走滑作用；b)挤压期的褶皱、冲断和走滑压扭作用；c）引张期的正断层或多米诺断裂系统和张扭走滑作用形成的盆地。它们发生于3个构造事件期间：Sougnim、Daebo和Bulgugsa造山期。晚二叠世一早三叠世的 Songuim 造山可分为两个阶段。当Songnim造山作用减弱时，后构造花岗岩石发生侵位，在张性构造环境下形成 Daedong盆地。晚三叠世-早侏罗世 Daedong 群沉积之后，Daebo造山随之发生，形成NE走向的褶皱和  相似文献   

First report of the small bird track Koreanaornis from the Cretaceous of North America: implications for avian ichnotaxonomy and paleoecology     

Owen A. Anfinson  Martin G. Lockley  Sam Hyang Kim  Kyung Soo Kim  Jeong Yul Kim 《Cretaceous Research》2009,30(4):885-894

Although body fossils of shorebirds and shorebird-like species are extremely rare from the Cretaceous, rapid increase in the discovery of bird footprint sites provides valuable alternate evidence to help fill gaps in the story of the early evolution of shorebird-like species. Newly discovered bird tracks from the Albian-Cenomanian Dakota Formation in northeastern Utah represent the first report of the ichnogenus Koreanaornis from North America and only the second report of bird tracks from this formation. These tracks are not attributable to Aquatilavipes as previously claimed. Three well-preserved trackways are described and provisionally referred to Koreanaornis cf. hamanensis (Kim). However, a review of the ichnotaxonomy of shorebird ichnites reveals that this ichnotaxon also closely resembles the Miocene ichnospecies Avipeda sirin (Vyalov). This latter comparison points to the need for a thorough evaluation of the similarity between Mesozoic and Cenozoic avian ichnotaxa, which may be over-split in some cases and under-differentiated in others.The new material helps distinguish ichnogenus Koreanaornis from the larger bird track Aquatilavipes, which is more abundant and widespread in North America. In some cases Aquatilavipes has been incorrectly used as a catch-all ichnogenus both in North America and Asia. The Dakota Formation stratigraphy at the tracksite indicates that the track makers lived in a marginal marine paleoenvironment. However, despite the widespread distribution of such facies, often replete with dinosaur tracks, the bird track record of the Dakota Formation, and the Cretaceous of the western USA remains relatively sparse in comparison with other areas such as east Asia.  相似文献   

Provincialism and Nd-isotopic Composition of the Late Cambrian Conodonts from the Joseon Supergroup, Korea: Implications for Paleogeography     

Yong Lee  Heon Jeong 《Gondwana Research》1999,2(4):583-585

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YSDP102钻孔有孔虫动物群与南黄海东南部古水文重建   总被引：8，自引：0，他引：8  

李铁刚  李绍全  苍树溪  刘健  Jeong Hae Chang 《海洋与湖沼》2000,31(6):588-595

所研究的YSDP1 0 2钻孔岩心 (33°49.496′N ,1 2 5°45.0 0 9′E)是由韩国能源研究所和中国国土资源部海洋地质研究所于 1 995年 8月联合取自南黄海东南部水深 62m的巨厚泥质沉积区内 ,岩心长 60 65m。通过对岩心沉积物中浮游和底栖有孔虫动物群的分析 ,结合相应的AMS1 4 C测年数据 ,对黄海暖流及与其相伴生的南黄海东南部冷水体的形成及演化进行了初步的探讨。结果表明 ,黄海暖流及与其相伴生的南黄海东南部冷水体形成于距今约640 0日历年前。形成伊始 ,冷水体处于明显的强势状态 ,而暖流的强度却相对较弱 ,这一过程约持续了 2 2 0 0年左右 ,是南黄海东南部巨厚泥质沉积区的主要堆积期。直到距今 42 0 0日历年前后 ,黄海暖流的影响强度开始加强 ,冷水体相对减弱 ,直至达到现代的水文状态。  相似文献   

Timeline analysis and wavelet multiscale analysis of the AKARI All-Sky Survey at 90 μm     

Lingyu Wang  Michael Rowan-Robinson  Issei Yamamura  Hiroshi Shibai  Rich Savage  Seb Oliver  Matthew Thomson  Nurur Rahman  Dave Clements  Elysandra Figueredo  Tomotsugu Goto  Sunao Hasegawa  Woong-Seob Jeong  Shuji Matsuura  Thomas G. Müller  Takao Nakagawa  Chris P. Pearson  Stephen Serjeant  Mai Shirahata  Glenn J. White 《Monthly notices of the Royal Astronomical Society》2008,387(2):601-615

We present a careful analysis of the point-source detection limit of the AKARI All-Sky Survey in the WIDE-S 90-μm band near the North Ecliptic Pole (NEP). Timeline analysis is used to detect IRAS ( Infrared Astronomy Satellite ) sources and then a conversion factor is derived to transform the peak timeline signal to the interpolated 90-μm flux of a source. Combined with a robust noise measurement, the point-source flux detection limit at signal-to-noise ratio  (S/N) > 5  for a single detector row is  1.1 ± 0.1 Jy  which corresponds to a point-source detection limit of the survey of ∼0.4 Jy.
Wavelet transform offers a multiscale representation of the Time Series Data ( tsd ). We calculate the continuous wavelet transform of the tsd and then search for significant wavelet coefficients considered as potential source detections. To discriminate real sources from spurious or moving objects, only sources with confirmation are selected. In our multiscale analysis, IRAS sources selected above 4σ can be identified as the only real sources at the Point Source Scales. We also investigate the correlation between the non- IRAS sources detected in timeline analysis and cirrus emission using wavelet transform and contour plots of wavelet power spectrum. It is shown that the non- IRAS sources are most likely to be caused by excessive noise over a large range of spatial scales rather than real extended structures such as cirrus clouds.  相似文献   

Effective periods and seismic performance of steel moment resisting frames designed for risk categories I and IV according to IBC2009          下载免费PDF全文

Seong‐Hoon Jeong  Oh‐Sung Kwon  Kwang‐Ho Lee 《地震工程与结构动力学》2015,44(9):1427-1447

In current seismic design, structures that are essential for post‐disaster recovery, and hazardous facilities are classified as risk category IV and are designed with higher importance factors and stringent drift limits. These structures are expected to perform better in an earthquake event because a larger base shear and more stringent drift limit are used. Although this provision has been in the seismic design code over the last three decades, few studies have investigated the performance of essential structures. The aim of this study is to quantify the impact of higher importance factors and stringent drift limits on the seismic performance of steel moment resisting frames. A total of 16 steel structures are designed for Los Angeles and Seattle. Different risk categories are used for the design. The effects of the risk categories on the structural periods, and thus on the seismic force demand, are investigated. A suite of inelastic time history analyses are carried out to understand the probability of exceeding a specified limit state when the structures are subjected to different levels of earthquake events. The results show that the periods of the structures in risk category IV decrease by a factor of 0.5 to 0.8, and the strengths increase by a factor of 1.5 to 3.2. Seismic fragility analysis shows that the structures in risk category IV generally satisfy the probabilistic performance objectives. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

Full Waveform Inversion Using Student’s t Distribution: a Numerical Study for Elastic Waveform Inversion and Simultaneous-Source Method   总被引：1，自引：0，他引：1  

Woodon Jeong  Minji Kang  Shinwoong Kim  Dong-Joo Min  Won-Ki Kim 《Pure and Applied Geophysics》2015,172(6):1491-1509

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Three‐dimensional modelling of controlled‐source electromagnetic surveys using an edge finite‐element method with a direct solver     

Jeong‐Sul Son  Tae Jong Lee  Hee Joon Kim  Changsoo Shin 《Geophysical Prospecting》2014,62(6):1468-1483

A fully three‐dimensional finite‐element algorithm has been developed for simulating controlled‐source electromagnetic surveys. To exploit the advantages of geometric flexibility, frequency‐domain Maxwell's equations of the secondary electric field were discretised using edge‐based finite elements while the primary field was calculated analytically for a horizontally layered‐earth model. The resulting system of equations for the secondary field was solved using a parallel version of direct solvers. The accuracy of the algorithm was successfully verified by comparisons with integral‐equations and iterative solutions, and the applicability to models containing large conductivity contrasts was verified against published data. The advantages of geometry‐conforming meshes have been demonstrated by comparing different mesh systems to simulate an inclined sheet model. A comparison of the performance between direct and iterative solvers demonstrated the superior efficiency of direct solvers, particularly for multisource problems.  相似文献   

MgO‐Based Binder for Treating Contaminated Sediments: Characteristics of Metal Stabilization and Mineral Carbonation          下载免费PDF全文

Kyung‐Yup Hwang  Jeong‐Yun Seo  Hoang Q. H. Phan  Jun‐Young Ahn  Inseong Hwang 《洁净——土壤、空气、水》2014,42(3):355-363

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Design of a low-cost attitude determination GPS/INS integrated navigation system   总被引：3，自引：2，他引：3  

Dong-Hwan Hwang  Sang Heon Oh  Sang Jeong Lee  Chansik Park  Chris Rizos 《GPS Solutions》2005,9(4):294-311

Due to their complementary features of GPS and INS, the GPS/INS integrated navigation system is increasingly being used for a variety of commercial and military applications. An attitude determination GPS (ADGPS) receiver, with multiple antennas, can be more effectively integrated with a low-cost IMU since the receiver gives not only position and velocity data but also attitude data. This paper proposes a low-cost attitude determination GPS/INS integrated navigation system. The proposed navigation system comprises an ADGPS receiver, a navigation computer unit (NCU), and a low-cost commercial MEMS IMU. The navigation software includes a fault detection and isolation (FDI) algorithm for integrity. In order to evaluate the performance of the proposed navigation system, two flight tests have been performed using a small aircraft. The first flight test confirmed the fundamental operation of the proposed navigation system and the effectiveness of the FDI algorithm. The second flight test evaluated the performance of the proposed navigation system and demonstrated the benefit of GPS attitude information in a high dynamic environment. The flight test results show that the proposed ADGPS/INS integrated navigation unit gives reliable navigation performance even when anomalous GPS data is provided and gives better navigation performance than a conventional GPS/INS unit.  相似文献