RETRACTED ARTICLE: Soil nutrient bioavailability and nutrient content of pine trees (Pinus thunbergii) in areas impacted by acid deposition in Korea     

Jae E. Yang  Wi-Young Lee  Yong Sik Ok  Jeffrey Skousen 《Geochemistry International》2008,46(9):951-957

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Some stability properties of large-scale baroclinic flows with nonlinear zonal current profile     

Jae Min Hyun 《Journal of Oceanography》1977,33(2):55-60

The stability properties of a baroclinic zonal current with nonlinear velocity profile are investigated. The integral method is applied to the governing eigenvalue equation having the vertical velocity as the dependent variable. Expressed in terms of the Rossby number and the Richardson number, stability criteria, unstable regions in the complexc plane, and the upper bound of the unstable wave growth rate are found. Some differences in the results are noted between the present model and the quasi-geostrophic streamfunction model, particularly in connection with the effect of the velocity profile curvature termU _zz . It is conjectured in the present model that, depending on extreme behaviors ofU _zz , the propagation speed of unstable waves can be greater thanU _max or smaller thanU _min .  相似文献   

Formation and distribution of manganese nodule deposit in the northwestern margin of Clarion-Clipperton fracture zones,northeast equatorial Pacific     

K. S. Jeong  J. K. Kang  K. Y. Lee  H. S. Jung  S. B. Chi  S. J. Ahn 《Geo-Marine Letters》1996,16(2):123-131

In the northwestern margin of the Clarion and Clipperton fracture zones, manganese nodules are latitudinally variable in character, resulting from the progressive (re)generation of nodules since the Oligocene as the Pacific Plate migrates northwestward beneath the equatorial production zone. Complemented by the surface water productivity, bottom current activities have concentrated nodules in the Oligocene to Miocene siliceous clay. Resedimentation processes on nodules form three types of nodules with concentric structures and 10 Å-manganaterich bottoms, by periodically causing the diagenetic growth of nodules within the topmost sediment layer.  相似文献   

Wave reflection from partially perforated-wall caisson breakwater   总被引：2，自引：0，他引：2  

Kyung-Duck Suh  Jae Kil Park  Woo Sun Park   《Ocean Engineering》2006,33(2):264-280

In 1995, Suh and Park developed a numerical model that computes the reflection of regular waves from a fully perforated-wall caisson breakwater. This paper describes how to apply this model to a partially perforated-wall caisson and irregular waves. To examine the performance of the model, existing experimental data are used for regular waves, while a laboratory experiment is conducted in this study for irregular waves. The numerical model based on a linear wave theory tends to over-predict the reflection coefficient of regular waves as the wave nonlinearity increases, but such an over-prediction is not observed in the case of irregular waves. For both regular and irregular waves, the numerical model slightly over- and under-predicts the reflection coefficients at larger and smaller values, respectively, because the model neglects the evanescent waves near the breakwater.  相似文献   

Determination of palladium and platinum in seaweed     

Jae Sam Yang 《Journal of Oceanography》1989,45(6):369-374

Palladium and platinum concentrations were determined for twenty two species of seaweed from the California coast, U.S.A.. A new sensitive analytical technique using atomic absorption spectrometry was developed for palladium in seaweed. For the first time, palladium contents in seaweed were obtained. The contents of palladium and platinum varied from 0.09 to 0.61 ng g^–1 and 0.25 to 1.75 ng g^–1 in dried material, respectively.The average ratio of Pt/Pd found in seaweed was 3.5, while the ratio of Pt/Pd was 4.5 in seawater. Therefore, it is postulated that there is no discrimination for seaweed to accumulate palladium and platinum from the ambient seawater due to the chemical similarity of the metals.  相似文献   

Rb-Sr and K-Ar systems of biotite in surface environments regulated by weathering processes with implications for isotopic dating and hydrological cycles of Sr isotopes     

Gi Young Jeong  Chang-Sik Cheong 《Geochimica et cosmochimica acta》2006,70(18):4734-4749

Biotite is widely used for Rb-Sr and K-Ar isotopic dating and influences Sr isotope geochemistry of hydrological regimes. The isotopic system of biotite behaves diversely in response to surface weathering; i.e. the complete preservation of original Rb-Sr and K-Ar isotopic ages or dramatic reduction. In this study, we have explored the relation between the behavior of isotopic systems and complex weathering processes of biotites in the weathering profiles distributed on the Mesozoic granitoids in South Korea. In the lower parts of the profiles, biotite in the early stages of weathering was transformed into either oxidized biotite or hydrobiotite, with a mass release of ⁸⁷Sr and ⁴⁰Ar forced by the rapid oxidation of ferrous iron. During the transformation to oxidized biotite, ⁸⁷Sr and ⁴⁰Ar were preferentially released relative to Rb and K, respectively, via solid-state diffusion through the biotite lattice, resulting in a drastic reduction of original isotopic age. The reduction of Rb-Sr age was greater than that of K-Ar age because K was preferentially released over Rb whereas ⁸⁷Sr and ⁴⁰Ar were released proportionally to each other. However, during the transformation of biotite to hydrobiotite (i.e., to regularly interstratified biotite-vermiculite), ⁸⁷Sr, Rb, ⁴⁰Ar, and K were completely retained in the alternating biotite interlayer, and thus the original isotopic age can be preserved. In the upper parts of the profiles, where iron oxidation was almost completed, ⁸⁷Sr, Rb, ⁴⁰Ar, and K were gradually and proportionally released, with no further significant change in isotopic age during the gradual transformation of the early-formed oxidized biotite into hydrobiotite and vermiculite or during their final decomposition to kaolinite. The ratios and amounts of isotopes released from weathered biotites are dependent upon the degree of iron oxidation and the pathways of mineralogical transformation. Regional and local variations in isotopic systems affected by particular weathering processes should be considered when dating biotite or biotite-bearing rocks in weathering environments, modeling the transfer of Sr isotopes to hydrologic regimes, and tracking the provenance of sediments.  相似文献   

Probabilistic approach for active control of structures: experimental verification     

Jae‐Seung Hwang  Kyung‐Won Min  Sang‐Hyun Lee  Hongjin Kim 《地震工程与结构动力学》2005,34(3):207-225

In our previous study (Earthquake Engineering and Structural Dynamics 2003; 32 :2301), we have developed a probabilistic algorithm for active control of structures. In the probabilistic control algorithm, the control force is determined by the probability that the structural energy exceeds a specified target critical energy, and the direction of a control force is determined by the Lyapunov controller design method. In this paper, an experimental verification of the proposed probabilistic control algorithm is presented. A three‐story test structure equipped with an active mass driver (AMD) has been used. The effectiveness of the control algorithm has been examined by exciting the test structure using a sinusoidal signal, a scaled El Centro earthquake and a broadband Gaussian white noise; and, especially, experiments on control have been performed under different conditions to that of system identification in order to prove the stability and robustness of the proposed control algorithm. The experimental results indicate that the probabilistic control algorithm can achieve a significant response reduction under various types of ground excitations even when the modeling error exists. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

A study on simulation of flood inundation in a coastal urban area using a two-dimensional well-balanced finite volume model     

Woochang Jeong 《Natural Hazards》2015,77(1):337-354

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Will economic growth and fossil fuel scarcity help or hinder climate stabilization?     

Elmar Kriegler  Ioanna Mouratiadou  Gunnar Luderer  Nico Bauer  Robert J. Brecha  Katherine Calvin  Enrica De Cian  Jae Edmonds  Kejun Jiang  Massimo Tavoni  Ottmar Edenhofer 《Climatic change》2016,136(1):7-22

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Performance Assessment of Hard Rock TBM and Rock Boreability Using Punch Penetration Test     

Ho-Young Jeong  Jung-Woo Cho  Seokwon Jeon  Jamal Rostami 《Rock Mechanics and Rock Engineering》2016,49(4):1517-1532

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