• Title/Summary/Keyword: northeastern China

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Ground support performance in deep underground mine with large anisotropic deformation using calibrated numerical simulation (case of mine-H)

  • Hu, Bo;Sharifzadeh, Mostafa;Feng, Xia-Ting;Talebi, Roo;Lou, Jin-Fu
    • Geomechanics and Engineering
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    • v.21 no.6
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    • pp.551-564
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    • 2020
  • High-stress and complex geological conditions impose great challenges to maintain excavation stability during deep underground mining. In this research, large anisotropic deformation and its management by support system at a deep underground mine in Western Australia were simulated through three-dimensional finite-difference model. The ubiquitous-joint model was used and calibrated in FLAC3D to reproduce the deformation and failure characteristics of the excavation based on the field monitoring results. After modeling verification, the roles of mining depth also the intercept angle between excavation axis and foliation orientation on the deformation and damage were studied. Based on the results, quantitative relationships between key factors and damage classifications were presented, which can be used as an engineering tool. Subsequently, the performance of support system installation sequences was simulated and compared at four different scenarios. The results show that, first surface support and then reinforcement installation can obtain a better controlling effect. Finally, the influence of bolt spacing and ring spacing were also discussed. The outcomes obtained in this research may play a meaningful reference for facing the challenges in thin-bedded or foliated ground conditions.

The Concepts of the Landscape : An Interpretation of related Chinese Characters (경'과 관련 술어의 개념에 관한 고찰 : 관련된 한자어의 해석을 중 심으로)

  • 황기원
    • Journal of the Korean Institute of Landscape Architecture
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    • v.22 no.4
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    • pp.23-36
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    • 1995
  • This study aims at scrutinizing the etymological meanings and literal usages of the term Gyung perse so as to clarify the traditional concepts formualted in the northeastern Asian countries. Related classical dictionaries and literatures in Korea and China were consulted intensively. Strictly speaking, the compound word gyung-gwan(景觀) composed of gyung(景:seen objects) and gwan(觀:seeing) in terms of word formation is not the synonym of the English term Landscpe. The Chinese character Gyung(景) composed of the character il(日:the Sun) and the character gyung(京:royal palace or capital city) originally indicated a brilliant and beautiful view of the capital city seen in a clear and bright daylight. Thereafter this ideographic letter had been used to indicate an unusual view which is aesthetically and can be used as a typical landscape schema or a model. Due to intrinsic nature of this kind of view, the meanings of gyung had been extended connotativelly as well as denotativelly: the meaning worthy of note in terms of landscape studies ar l) visible object which places some physical and psychological distance from the observer; 2)the scene or the backdrop of a theater, 3)a defined vista. With these in mind, meanings and usages of related terms as Kwung(光:light or bright), Pung(風:wind or fresh). Chi(致:fine), Mul(物:object or world), Gae (槪:general), Seung(勝:outstanding or surpassing), Saek(色:color or colorful), which had produced diversified and delicate connotations through compounding with the etymon Gyung, were reviewed.

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Assessment of Vegetation Recovery after Forest Fire

  • Yu, Xinfang;Zhuang, Dafang;Hou, Xiyong
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.328-330
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    • 2003
  • The land cover of burned area has changed dramatically since Daxinganling forest fire in Northeastern China during May 6 ? June 4, 1987. This research focused on determining the burn severity and assessment of forest recovery. Burned severity was classified into three levels from June 1987 Landsat TM data acquired just after the fire. A regression model was established between the forest canopy closure from 1999 forest stand map and the NDVI values from June 2000 Landsat ETM+ data. The map of canopy closure was got according to the regression model. And vegetation cover was classified into four types according to forest closure density. The change matrix was built using the classified map of burn severity and vegetation recovery. Then the change conversions of every forest type were analyzed. Results from this research indicate: forest recovery status is well in most of burned scars; and vegetation change detection can be accomplished using postclassification comparison method.

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Taxonomic identity of the plant name Sanggisaeng (식물명 상기생(桑寄生)의 분류학적 실체)

  • SHIN, Hyunchur;JUNG, Jongduk
    • Korean Journal of Plant Taxonomy
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    • v.48 no.4
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    • pp.357-362
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    • 2018
  • References in the modern Korean literature in this area to the Korean medicinal plant name written in Chinese script and expressed as Sanggisaeng have been extremely confusing. This name has been considered as six species, specifically Loranthus parasiticus, Loranthus tanakae, Taxillus yadoriki, Taxillus chinensis, Korthalsella japonica, and Viscum album var. coloratum. Recently, it was suggested that sanggisaeng is not distributed in Korea; however, the plant name Sanggisaeng recorded in old Korean literature sources, such as in the Hyang-yak-chae-chwi-wol-lyeong, Hyang-yak-jib-seong-bang, and Dong-ui-bo-gam sources, among others, was identified using the name V. album var. coloratum, whereas in China, Sanggisaeng was referred to as T. sutchuenensis. The Hangeul name of Sanggisaeng had been Ppongnamugyeousali, but now the name Gyeousali is widely used.

Summarize Water-soluble Ions of $PM_{2.5}$ in Northeastern Asia

  • Z. He;Seong Y. Ryu;Kim, Jeong E.;K. O. Ogunjobi;Kim, Young J.
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2003.11a
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    • pp.400-401
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    • 2003
  • Atmospheric fine aerosol particles play an important role in controlling a number of atmospheric processes, such as the deposition of different compounds, the optical properties etc. (Molnar et al., 1999). In this report, water-soluble species of PM$_{2.5}$ obtained from simultaneous measurements at four Asia sites (Beijng (39.56$^{\circ}$N, 116.17$^{\circ}$E), China; Gwangju (35.10$^{\circ}$N, 126.53$^{\circ}$E), South Korea; Kyoto (35.01$^{\circ}$N, 135.44$^{\circ}$E), Japan; and Ulan-Bator (47.55$^{\circ}$N, 106.52$^{\circ}$E), Mongolia) during the periods of 14-22 August, 30 October-06 November 2000, 14-21 January 2001, 23 July-02 August and 05-16 November 2002, within the framework of an APN (The Asia-Pacific Network for Global Change Research) project are reported. Ion components in 23 July-02 August 2002 were not obtained because of the technical problem of equipments.s.

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Genetic variation of the endangered species Halenia coreana (Gentianaceae)

  • YUN, Narae;OH, Sang-Hun
    • Korean Journal of Plant Taxonomy
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    • v.52 no.1
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    • pp.45-53
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    • 2022
  • Halenia coreana is an endangered, endemic species that is distributed in only a few locations in Korea, such as Mts. Hwaaksan and Daeamsan. It has been recently segregated from H. corniculata, broadly distributed in cold temperate regions that include northern Japan, the Russian Far East, northeastern China, Mongolia, and eastern Europe, where population sizes are usually large. To examine the genetic diversity of H. coreana and evaluate the level of genetic differentiation of the species compared with that of H. corniculata, we surveyed 183 candidate simple sequence repeats (SSR) motif markers for H. coreana and H. corniculata from sequence data of amplified fragments of a specific length in the genome. A total of 17 genomic-SSR markers were selected to examine the levels of genetic diversity and differentiation using 17 samples of H. coreana and 60 samples of three populations of H. corniculata. The results here suggest that the genetic diversity of H. coreana is very low with a high frequency of inbreeding within its population. We found that H. coreana is genetically differentiated from H. corniculata, supporting the recognition of the geographically isolated H. coreana as a distinct species.

Genetic Structure of the Jellyfish Rhopilema esculentum (Scyphozoa: Rhizostomatidae) in Korean Coastal Waters

  • Soo-Jung Chang;Jang-Seu Ki;Won-Duk Yoon;Ga-Eun Jun
    • Animal Systematics, Evolution and Diversity
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    • v.39 no.4
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    • pp.264-271
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    • 2023
  • The edible jellyfish Rhopilema esculentum occurs in waters throughout northeastern Asia, including in Korea, China, and Japan. In Korean waters, R. esculentum has appeared in two regions (Gangwha and Muan). Based on the appearance of young medusae and coastal distribution records, these two regions may be key R. esculentum breeding sites. In the present study, we investigate and compare the genetic structure of R. esculentum in the two regions using mitochondrial sequences (16S ribosomal RNA and cytochrome c oxidase subunit I). The genetic diversity of the R. esculentum population at Ganghwa exceeded that of the population at Muan. Despite considerable geographic separation (400 km) between the two regions(Gangwha and Muan), our haplotype network suggests that the Gangwha and Muan populations of R. esculentum are related. The simple and monotonous genetic structure of the Muan population shows that R. esculentum emergence is relatively recent. In contrast, the Gangwha population shows evolution. Moreover, jellyfish of the Gangwha population are genetically diverse and remain constant despite environmental fluctuations in the Han River. The Gangwha area is considered to be the old origin of R. esculentum in Korea.

A case of chronic licorice intoxication-induced apparent mineralocorticoid excess syndrome (만성 감초 중독으로 유발된 미네랄코르티코이드 과잉증후군 1예)

  • Young Jae Lim;Ji Eun Kim
    • Journal of The Korean Society of Clinical Toxicology
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    • v.21 no.2
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    • pp.151-155
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    • 2023
  • Licorice is a perennial herb belonging to the legume family that mainly grows in northeastern China, Mongolia, Siberia, and other regions. It is used in traditional medicine in the form of dried roots in the East and the West. The main active component of licorice, glycyrrhizin, is known to produce mineralocorticoid effects when consumed chronically, which can lead to apparent mineralocorticoid excess syndrome. Herein, we present the case of a 72-year-old woman who was admitted to the emergency room with severe generalized weakness and difficulty keeping her neck upright, which had developed after daily consumption of licorice-infused water for the past 2 months. Blood tests revealed metabolic alkalosis and severe hypokalemia, and an electrocardiogram showed ventricular bigeminy. The patient was treated with daily potassium and spironolactone supplements, leading to a significant improvement in muscle strength after a week. One week later, the patient was discharged, showing rare ventricular premature contractions on electrocardiography, but with no specific complaints. Chronic licorice ingestion leading to hypokalemia and muscle weakness can be life-threatening, necessitating the discontinuation of the causative agent, close monitoring, and cautious supplementation of potassium and spironolactone as treatment.

Analysis of Abnormal High Temperature Phenomena in Cixi-si of China using Landsat Satellite Images (Landsat 위성영상을 이용한 중국 츠시시의 이상 고온 현상 분석)

  • Park, Joon-Kyu;Lee, Jong-Sin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.8
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    • pp.34-40
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    • 2017
  • In recent years, global warming has caused abnormal weather phenomena. Unusually cold climates have occurred all around the world, including cold waves in the Northeastern United States, Beijing, China, Southern India, and Pakistan, as well as floods in Chile, Kazakhstan, and Vietnam. China has been experiencing a nationwide heat wave annually since the year 2013, especially in the southern region. In this study, we used Landsat 8 OLI TIRS sensor images from four periods to analyze the characteristics of abnormal high temperature phenomena in Cixi-si, China. Land cover classification was performed using 10 bands of satellite imagery, and the surface temperature was extracted using the 10th thermal band. The results of the land cover classification of the fourth period show the changes of the time series quantitatively. The results of the surface temperature calculation provided both the average overall temperature and the average temperature of individual items. The temperature was found to be highest for buildings, followed by grassland, forest, agricultural land, water systems, and tidal flats in the same period.

Clay minerals and geochemistry of continental shelf sediment around Jeju Island in the northern East China Sea (제주도 주변해역 대륙붕 퇴적물의 지화학적 조성과 점토광물 연구)

  • Youn, Jeung-Su
    • The Korean Journal of Quaternary Research
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    • v.23 no.1
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    • pp.25-37
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    • 2009
  • Geochemical composition and clay minerals of surface and core sediments around off the Jeju Island were analyzed for identification of sediment origins. The clay mineral distribution is mainly controlled by the sediment source and the dominant circulation pattern. Smectite is highly concentrated (>8%) in the northwest near the South Yellow Sea and in the outer-shelf mud patch. It seems to be due to the high supply of smectite transported from China where fine-grained sediments are discharged from modern and ancient Huanghe River. The relatively high abundance of kaolinite are found in northeastern nearshore area and the southwest near Changjiang estuary. It seems to be supplied from Changjiang River and the southwestern Korea rivers. The sediment accumulation rates measured by $^{210}Pb$ geochronrom mowere 0.20 to 0.54cm/mr or 0.15 to $0.42g/cm^2{\cdot}mr^{-1}$ AOJI, with decreasing rates from the west part to the east part, resulting in the supply of fine-grained suspended sediments from the Changjiang and Huanghe Rivers system. The discrimination diagrams clearly show that the sediments around Jeju Island in the northern East China Sea are ultimately sourced from Chinese rivers, especially from the Huanghe River, whereas the sediment in the northeast part might come from Korean rivers and the Jeju Island.

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