Effects of a Building＇s Density on Flow in Urban Areas     

Jae-Jin KIM Do-Yong KIM 《大气科学进展》2009,(1)

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材料复合桩的现场承载性能试验研究     

李宝建  李光范  胡伟  赵菲  金燦起 《岩土力学》2015,36(Z2):629-632

基于水平荷载作用下桩基的弯矩沿深度呈由上向下骤减的规律,将桩的上部设计为抗弯性能良好的钢管桩而下部为抗弯性能较弱的PHC桩,并选择适当的部位通过焊接等方式连接两种桩型。在现场进行锤击试验、水平承载力试验和连接部位抗弯性能试验,将复合桩的压应力、拉应力和水平承载力与材料允许值对比比较。结果表明,所选择的材料复合型桩充分发挥了材料性能,尤其在水平承载力方面表现突出,且不同材料桩型连接部位性能良好。试验结果为桩基的改进提供了新思路和试验依据。  相似文献   

Spatio-temporal variability in sea surface wind stress near and off the east coast of Korea   总被引：1，自引：1，他引：0  

NAM SungHyun  KIM Young Ho  PARK Kyung-Ae  KIM Kuh 《海洋学报(英文版)》2005,24(1):107-114

Sea surface wind stress variabilities near and off the east coast of Korea, are examined using 7 kinds of wind datasets from measurements at 2 coastal (land) stations and 2 ocean buoys,satellite scatterometer (QuikSCAT), and global reanalyzed products (ECMWF,NOGAPS,and NCEP/NCAR). Temporal variabilities are analyzed at 3 frequency bands; synoptic (2-20 d), intra-seasonal (20-90 d),and seasonal (>90 d).Synoptic and intra-seasonal  相似文献   

High-frequency acoustic backscattering characteristics for acoustic detection of the red tide species Akashiwo sanguinea and Alexandrium affine     

KIM Hansoo  KANG Donhyug  JUNG Seung Won  KIM Mira 《中国海洋湖沼学报》2019,(4)

Harmful algal blooms(HABs),caused by the overgrowth of certain phytoplankton species,have negative effects on marine environments and coastal fisheries.In addition to cell-counting methods using phytoplankton nets,a hydroacoustic technique based on acoustic backscattering has been proposed for the detection of phytoplankton blooms.However,little is known of the acoustic properties of HAB species.In this study,as essential data to support this technique,we measured the acoustic properties of two HAB species,Akashiwo sanguinea and Alexandrium affine,which occur in the South Sea off the coast of Korea.Due to the small size of the target,we used ultrasound for the measurements.Experiments were conducted under laboratory and field conditions.In the laboratory experiment,the acoustic signal received from each species was directly proportional to the cell abundance.We derived a relationship between the cell abundance and acoustic signal received for each species.The measured signals were compared to predictions of a fluid sphere scattering model.When A.sanguinea blooms appeared at an abundance greater than 3 500 cells/mL,the acoustic signals varied with cell abundance,showing a good correlation.These results confirm that acoustic measurements can be used to detect HAB species.  相似文献   

Correlation assessment and monitoring of the potential pollutants in the surface sediments of Pyeongchang River, Korea   总被引：1，自引：0，他引：1  

Md.Imran KABIR  Hosik LEE  Geonha KIM  Taesung JUN 《国际泥沙研究》2011,26(2):152-162

The study provides a baseline for the assessment of the organic and inorganic pollution specially, heavy metal contamination in the surface sediments of Pyeongchang River,South Korea.The assessment of the study areas was done with respect to metal pollution load,ecological risk and geoaccumulated risk.Based upon the used indices,a priority index(P_index) was used to rank the utmost contaminated sites.Though the concentrations of mercury in all sediments were below the guideline, the significant enriched contamination was observed by all applied indices.As expected,the values of pollution load index（PLI）,ecological risk index（RI） and geoaccumulation risk index(I_geo) demonstrated lower heavy metal contamination in upstream areas compared to the downstream. Admittedly,sediments were unpolluted to slightly-polluted according to PLI while high to extremely high ecological risks were observed in several sediment samples.Furthermore,all the samples were uncontaminated as per I_geo.After simplification of I_geo,the P_index,showed the utmost contaminated sediments with a value of 2.537.Notably,protective measures should be taken to the highly contaminated areas which are prioritized by P_index Admittedly,the maximum concentrations of total organic carbon,total nitrogen,inorganic nitrogen,total phosphorous,inorganic phosphorous,calcium, magnesium,sodium and potassium were significantly observed as 7.8×10⁴,3,185,36,1,032,3.7, 1,5163,2,881,669 and 4,076mg/kg accordingly.  相似文献   

Energy Consumption and Greenhouse Gas Emission of Korean Offshore Fisheries     

LEE Jihoon  KIM Taeho  ELLINGSEN Harald  HOGNES Erik Skontorp  HWANG Bokyu 《中国海洋大学学报(英文版)》2018,(3)

This paper presents the energy and greenhouse gas(GHG) emission assessments of Korean offshore fisheries. The consumption of energy by fisheries is a significant concern because of its attendant environmental effect, as well as the cost of the fuel consumed in fishing industry. With the global attention of reducing GHG emission and increasing energy efficiency of fuel, the seafood industry needs to further understand its energy use and reduce its GHG emission. In the present study, the amount of energy consumed and the GHG emission of Korean offshore fisheries in a period from 2009 to 2013 were examined. Offshore fisheries accounted for 24% of Korean production in 2013 and 60% of fuel consumption related GHG emission. Whereas the total GHG emission intensity of this sector improved slightly between 2009 and 2012; as such emission decreased by approximately 1.9%, which increased again in 2013. The average amount of total GHG emission in this five years period was 1.78 × 10~6 tons of carbon dioxide equivalent/year(tCO_2eq. y~(-1)). Active fishing gear was found to consume 20% more fuel than passive gear. However, the production from passive gear was 28%, lower than 72% from active gear. The reason for this is that less abundant stationary resources are harvested using passive gear. Furthermore, the consumption of fuel was significantly influenced by the fishing method. Implementation and development of new fishing technologies and methods are important for improving energy efficiency and reducing the climate impact on fisheries. To realize these purposes, the fishery management system needs to be established by centralizing on energy efficiency and climate effect.  相似文献   

Precambrian crustal evolution in Rangrim Massif , Korean Peninsula   总被引：2，自引：0，他引：2  

LYANG To Jun  LIU Yongjiang  YANG Jong Hyok  KIM Hon  HAN Ryong Yon  KIM Jong Nam 《世界地质(英文版)》2009,12(2):57-63

Petrological, chronological and geotectonic geological analysis of Precambrian metamorphic rock in Korean Peninsula shows that the remnants ( > 314 Ga) of continental nuclei crust were formed in the Paleo-archean in the Rangrim Massif. In the massif, the main formation ages of continental crust range from 3.2 Ga to 2.5 Ga, its important growing period was 2.8 - 2.5 Ga. The subsequent expansion period of the Rangrim Massif was 2.4 - 2.2 Ga. The division events occurred in 1.85 Ga and in the Late Paleoproterozoic－Early Mesoproterozoic, respectively. Since then the massif was relatively stable. However, the last division of the Rangrim Massif occurred at 793 Ma.  相似文献   

Late Middle Pleistocene glaciation in East Anglia, England   总被引：1，自引：0，他引：1  

PHILIP L. GIBBARD  ANTTI H. PASANEN  RICHARD G. WEST  JUHA PEKKA LUNKKA  STEVE BOREHAM  KIM M. COHEN  CHRISTOPHER ROLFE 《Boreas: An International Journal of Quaternary Research》2009,38(3):504-528

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Variability of the Dokdo Abyssal Current observed in the Ulleung Interplain Gap of the East/Japan Sea     

KIM Yun-Bae  CHANG Kyung-Il  PARK Jae-Hun  PARK Jong Jin 《海洋学报(英文版)》2013,32(1):12-23

Subinertial fluctuation of a strong northward deep current, which is referred to the Dokdo Abyssal Current (DAC) by Chang et al. (2009), is investigated from current records for about 16.5 and 8.0 months in the Ulleung Interplain Gap of the East/Japan Sea. The current below 300 m is bottom-intensified and has nearly depth-independent flow. Near bottom, the spectral peaks of the current were found near 10, 20, and 60 d. The DAC variability near 10 d and 20 d is reasonably consistent with the linear theory of topographic Rossby waves (TRWs) in the following aspects: (1) The motion is columnar and bottom-intensified; (2) the theoretical cutoff frequency is similar to the observation; (3) The observation-based angles of the wavenumber vector are in good agreement with the theoretical ones. The wavelengths of the TRWs with periods of near 10 d and 20 d near Dokdo are significantly shorter than those with similar timescales in the open oceans (100-250 km). It is primarily due to the weak stratification below 300 m in the East Sea. The deep current fluctuations with periods of near 10 d and 20 d were accompanied by warm events in the upper layer resulting from eddying processes and/or meandering of the Tsushima Warm Current.  相似文献   

The temporal and spatial variability of the Yellow Sea Cold Water Mass in the southeastern Yellow Sea, 2009-2011   总被引：1，自引：1，他引：0  

OH Kyung-Hee  LEE Seok  SONG Kyu-Min  LIE Heung-Jae  KIM Young-Taeg 《海洋学报(英文版)》2013,32(9):1-10

The Yellow Sea Cold Water Mass(YSCWM) is one of the important water mass in the Yellow Sea(YS).It is distributed in the lower layer in the Yellow Sea central trough with the temperature less than 10 C and the salinity lower than 33.0.To understand the variability of the YSCWM,the hydrographic data obtained in April and August during 2009–2011 are analyzed in the southeastern Yellow Sea.In August 2011,relatively warm and saline water compared with that in 2009 and 2010 was detected in the lower layer in the Yellow Sea central area.Although the typhoon passed before the cruise,the salinity in the Yellow Sea central trough is much higher than the previous season.It means that the saline event cannot be explained by the typhoon but only by the intrusion of saline water during the previous winter.In April 2011,actually,warm and saline water(T >10 C,S >34) was observed in the deepest water depth of the southeastern area of the Yellow Sea.The wind data show that the northerly wind in 2011 winter is stronger than in 2009 and 2010 winter season.The strong northerly wind can trigger the intrusion of warm and saline Yellow Sea Warm Current.Therefore,it is proposed that the strong northerly wind in winter season leads to the intrusion of the Yellow Sea Warm Current into the Yellow Sea central trough and influenced a variability of the YSCWM in summer.  相似文献