• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1997.04a
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• pp.77-87
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• 1997

The earthquake data(M$\geq$4.0) for post-1900 in the Korean Peninsula show temporal variation with active and quiet periods. The pattern is quite similar to northeastern China and Inner Zone of Southwest Japan. Yeongweol earthquake occurred in the seismic gap region of the Korean Peninsula. This is the first medium-size earthquake in inland region of the southern peninsula since 1978. The intensity based on the felt area estimation of about 400 places shows MMI III-Ⅷ in inland region. IIon Cheju Island and Ion Ulreung Island. The isoseismal of MMI Ⅶ shows an elongated circle in the direction of NE-SW and covers some parts of Jungdong-myon, Yeongweol-kun, Sindong-eup and Nam-myun, Jeongseon-kun. There occurred quite strong shaking, numerous cracks on the walls of buildings, falling and movement of slate and tiles on the roofs, falling of tiles from the wall and falling of materials from desks, rook falling from mountain and collapse of gravel lauers on the river side. The least square fitting of the intensity data of the Yeongweol earthquake by a popular intensity attenuation relation yields the following : I=Io＋1.82249 - 0.65295*InR - 0.00707*R

• Journal of the Korean earth science society
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• v.35 no.5
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• pp.354-361
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• 2014

Fault plane solutions in North Korea and the northern part of the Yellow Sea ($37.5^{\circ}N-40.5^{\circ}N$, $124.5^{\circ}E-128.5^{\circ}E$) was studied for the earthquakes that occurred from November, 2008 to May, 2013. The analysis was based on the data collected from seismic networks in Korea and China. Fault plane solutions were obtained from P and SH wave polarities and SH/P amplitude ratioes. Most earthquakes exhibited predominantly strike-slip fault characteristics with NNE-SSW or WNW-ESE nodal planes. The P-axes trends are mainly NE-SW or ENE-WSW direction in the northern part of the Yellow Sea and inland area of North Korea except some areas in the Hwanghae province. Fault plane solutions and main axis of stress field in the study region were similar to those observed in the southern part of the Korean Peninsula.

• Economic and Environmental Geology
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• v.46 no.5
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• pp.391-409
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• 2013

The Hongseong area of the southwestern Gyeonggi massif is considered to be part of suture zone that is tectonically correlated with the Qinling-Dabie-Sulu belt of China in terms of the preservation of collisional evidences during Triassic in age. The Wolhyeonri complex, preserved at the center of the Hongseong area, consists mainly of Neoproterozoic orthogneisses and Middle Paleozoic intermediate- to high-grade metamorphic schists, orthogneisses and mafic metavolcanics. The area includes various Middle to Late Triassic intrusives (e.g. dyke or stock). They are mainly monzonite and aplite with small intrusions of monzodiorit, syenite and diorite in composition. The SHRIMP U-Pb zircon ages yield 237 Ma to 222 Ma. The geochemistry of the studied Triassic intrusives show similar subuction- or arc-type signatures having Ta-Nb troughs, depletion of P and Ti, and enrichment of LILEs (large ion lithophile elements). In addition, the Triassic plutons in the Hongseong area, including those from this study, mostly possess high-K calc-alkaline to shoshonitic tectonic affinity. These results could be tectonically correlated to the post-collisional magmatic event following the Triassic collision between the North and South China blocks in China. Therefore, the Triassic plutons in the Hongseong area offer an important insight into the Triassic geodynamic history of the NE Asian region.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.7 no.3
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• pp.265-276
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• 1995

In this Paper, the Performance of the convolution method has been investigated as an effort to develop a simple system of predicting wind-driven surface current on a real time basis. In this approach wind stress is assumed to be spatially uniform and the effect of atmospheric pressure is neglected. The discrete convolution weights are determined in advance at each point using a linear three-dimensional Galerkin model with linear shape functions(Galerkin-FEM model). Four directions of wind stress(e.g. NE, SW, NW, SE) with unit magnitude are imposed in the model calculation for the construction of data base for convolution weights. Given the time history of wind stress, it is then possible to predict with-driven currents promptly using the convolution product of finite length. An unsteady wind stress of arbitrary form can be approximated by a series of wind pulses with magnitude of 6 hour averaged value. A total of 12 pulses are involved in the convolution product To examine the accuracy of the convolution method a series of numerical experiments has been carried out in the idealized basin representing the scale of the Yellow Sea and the East China Sea. The wind stress imposed varies sinusoidally in time. It was found that the predicted surface currents and elevation fields were in good agreement with the results computed by the direct integration of the Galerkin model. A model with grid 1/8$^{\circ}$ in latitude, l/6$^{\circ}$ in longitude was established which covers the entire region of the Yellow Sea and the East China Sea. The numerical prediction in terms of the convolution product has been carried out with particular attention on the formation of upwind flow in the middle of the Yellow Sea by northerly wind.

• Economic and Environmental Geology
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• v.30 no.6
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• pp.613-624
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• 1997

A study of anisotropy of magnetic susceptibility (AMS) was conducted on the Ordovician-Eocene strata in the Taebaek area. The study area is a northeastern part of the Okchon belt, sometimes called as Paegunsan Synclinal Area. A total of 600 independently oriented samples were collected from 60 sites covering the whole area. With a few exception of late Cretaceous-Eocene volcanic rocks, all the sampled strata are nonmetamorphosed sedimentary rocks, mainly sandstones. Among the 60 sites, 5 sites showed flow lineation lying on the bedding plane, 11 sites showed load foliation parallel to the bedding plane, and 21 sites showed tectonic foliation unrelated to the bedding plane. The tectonic foliations are defined by $k_1-k_2$ ($k_{max}-k_{int}$) anisotropy plane, and are considered as a result of tectonic forces acted perpendicularly to the foliation plane in the geologic past. Regardless of sample-site locations, tectonic force directions defined by $k_3$ ($k_{min}$) axis perpendicular to the tectonic foliation are consistent among the strata of the same geologic age. In the course of geologic time, however, the tectonic force directions showed a clockwise rotation: approximately E-W in the Ordovician sites, NW-SE in the Permian sites, N-S in the Triassic sites, and lastly NE-SW in the late Cretaceous-Eocene sites. The pre-Permian directions showed better clustering in the in-situ (geographic) coordinates, while the younger directions become better clustered after the bedding-tilt correction. It is interpreted that the major tectonic structures of the Taebaek area were controlled by the above-mentioned tectonic forces: The Paegunsan Syncline and the Hambaeksan Fault must have been generated by the NW-SE force of late Permian-early Triassic time. It was then reactivated in the reverse (dextral) sense by the N-S force of Triassic time. The Osipchon Fault in the eastern part of the study area was either generated or reactivated by the NE-SW force of late Cretaceous-Eocene time. The Permo-Triassic NW-SE force should be an expression of the Songnim Disturbance in the Korean peninsula, which is in turn related with the SCB/NCB collision in China.

• Journal of Korean Society of Forest Science
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• v.105 no.2
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• pp.208-215
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• 2016

Vaccinium oldhamii Miq. is a Korean native tree, which is deciduous and shrub tree with broad leaf. Fruits were used primarily for edible or medicinal purposes for bladder infection in Korea and China. However, there is a lack of information on the degree of variation of phytochemical contents and antioxidant activity of these native clonal. We investigated morphological characteristics, phytochemical contents (polyphenol, flavonoid, anthocyanin) and antioxidant activity for the fruits of 24 individual variation from 4 different regions in Korea. The results in terms of horticultural traits and biochemical characteristics showed significant differences among populations and among individuals within population. The total phenolic contents ranged from 4.40 to 10.58 mg GAE/g and the total flavonoid contents ranged from 2.02 to 8.09 mg NE/g. The total anthocyanin contents ranged from 232.5 to 684.3 mg CGE/100g. Reducing power fruits ranged from 0.15 to 1.43 and DPPH free radical scavenging activity ranged from 49.1 to 97.5% at 400 ppm. Results revealed that the region of origin greatly influenced the phytochemical contents and antioxidant activity of V. oldhamii, which might help for the selection and validation of the most productive cultivars in the food and pharmaceutical industries.

• Molecules and Cells
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• v.41 no.3
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• pp.244-255
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• 2018

Low-grade pro-inflammatory state and leptin resistance are important underlying mechanisms that contribute to obesity-associated hypertension. We tested the hypothesis that Astragaloside IV (As IV), known to counteract obesity and hypertension, could prevent obesity-associated hypertension by inhibiting pro-inflammatory reaction and leptin resistance. High-fat diet (HFD) induced obese rats were randomly assigned to three groups: the HFD control group (HF con group), As IV group, and the As IV + ${\alpha}$-bungaratoxin (${\alpha}-BGT$) group (As IV+${\alpha}-BGT$ group). As IV ($20mg{\cdot}Kg^{-1}{\cdot}d^{-1}$) was administrated to rats for 6 weeks via daily oral gavage. Body weight and blood pressure were continuously measured, and NE levels in the plasma and renal cortex was evaluated to reflect the sympathetic activity. The expressions of leptin receptor (LepRb) mRNA, phosphorylated signal transducer and activator of transcription-3 (p-STAT3), phosphorylated phosphatidylinositol 3-kinase (p-PI3K), suppressor of cytokine signaling 3 (SOCS3) mRNA, and protein-tyrosine phosphatase 1B (PTP1B) mRNA, pro-opiomelanocortin (POMC) mRNA and neuropeptide Y (NPY) mRNA were measured by Western blot or qRT-PCR to evaluate the hypothalamic leptin sensitivity. Additionally, we measured the protein or mRNA levels of ${\alpha}7nAChR$, inhibitor of nuclear factor ${\kappa}B$ kinase subunit ${\beta}/nuclear$ factor ${\kappa}B$ ($IKK{\beta}/NF-KB$) and pro-inflammatory cytokines ($IL-1{\beta}$ and $TNF-{\alpha}$) in hypothalamus and adipose tissue to reflect the anti-inflammatory effects of As IV through upregulating expression of ${\alpha}7nAChR$. We found that As IV prevented body weight gain and adipose accumulation, and also improved metabolic disorders in HFD rats. Furthermore, As IV decreased BP and HR, as well as NE levels in blood and renal tissue. In the hypothalamus, As IV alleviated leptin resistance as evidenced by the increased p-STAT3, LepRb mRNA and POMC mRNA, and decreased p-PI3K, SOCS3 mRNA, and PTP1B mRNA. The effects of As IV on leptin sensitivity were related in part to the up-regulated ${\alpha}7nAchR$ and suppressed $IKK{\beta}/NF-KB$ signaling and pro-inflammatory cytokines in the hypothalamus and adipose tissue, since co-administration of ${\alpha}7nAChR$ selective antagonist ${\alpha}-BGT$ could weaken the improved effect of As IV on central leptin resistance. Our study suggested that As IV could efficiently prevent obesityassociated hypertension through inhibiting inflammatory reaction and improving leptin resistance; furthermore, these effects of As IV was partly related to the increased ${\alpha}7nAchR$ expression.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.9
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• pp.1282-1287
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• 2011

The objective of this study was to assess the effect of xylanase on net energy for production, performance, nutrient digestion and gut microflora of broilers fed corn/soy-based diet. Eighty-four day-old male broiler chicks were allocated to two groups receiving two treatments, respectively. Each treatment had six replicate cages with seven broilers per cage. The diets were based on corn and soybean. The treatments were: i) basal diet reduced in apparent metabolizable energy (-0.63 MJ/kg compared to commercial diet specifications); ii) basal diet supplemented xylanase at 4,000 u/kg feed. The experiment used the auto-control, open circuit respiration calorimetry apparatus to examine the heat production and net energy for production. The results revealed that xylanase supplementation did not affect growth performance and diet AME value, but increased $NE_p$ value by 18.2% (p<0.05) and decreased daily heat production per $kg^{0.75}$ by 31.7% (p<0.05). There was no effect (p>0.05) of xylanase supplementation on the ileal digestibility of N and hemicelluloses, but the ileum digestibility of energy was increased by 2% by xylanase supplementation (p<0.05). Xylanase supplementation increased (p<0.05) the count of lactobacillus and bifidobacterial in the caecum.

• Journal of the Korean association of regional geographers
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• v.18 no.4
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• pp.351-363
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• 2012

Although the Korean peninsula has been considered as a largely aseismic region compared with the surrounding high seismic areas such as North China and Japan, there are more than thirty Quaternary faults reported so far, which are mostly centered in the southeastern peninsula. Structural studies of active faults exposed in Yangnam-myeon of Gyeongju, SE Korea are largely interpreted to post date the late Quaternary, suggesting that the NE-trending reverse faults may result from the active stress regime in the peninsula. The prevailing present-day E-W $S_{Hmax}$ orientations in the peninsula are consistent with the nature of plate forcing stemming from the convergence between the Indo-Australian and Eurasian plates. It is clear that the Quaternary faults have been reactivated, although resolving more elaborate time intervals responsible for a future rupture remains a significant challenge. This study contributes to better assess many of potential seismic hazards in the study area, in particular, in terms of seismic stability for foundation of nuclear power plant.

• Korean Journal of Oriental Medicine
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• v.9 no.1
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• pp.1-33
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• 2003

From the study on Doo-Jong Kims view of history about the early Korea$(Korea\;herewith\;stands\;for\;Korea\;dynasty\;A.D.918{\sim}1392)s$ Medicine, I came to a conclusion as follows. 1. Doo-Jong Kim is stressing on the fact that Early Koreas Medicine inherited from Shilla dynasty and seemingly expressing the pride of national medical science. But actually he distorted the Koreas independent growth with flunkeyism and insisted that Koreas medicine only took over Shilla dynastys which based on Chinese Tang dynastys medical science. As a result, Koreas medicine was blurred and evaluated as nothing but Tangs medicine. But, the reasons of Doo-Jong Kims viewpoints were not based on the fact, but on his speculation. 2. About the medical system, Doo-Jong Kim viewed that Korea copied Chinese Soo & Tangs medical system, But the fact is that Korea only borrowed a part of Chinese medical systems name, for examples, Tae-I-Gam, Sang-Yak-Kook, Sang-Sik-Kook, etc., and its actual functions were different and grew in Koreas own way, As a result, the titles or roles in the system were very different from those of Chinas. Especially, Korea saw much development in Science of Acupuncture and Moxibustion that there was a specialist on Acupuncture, called I-Chim-Sa, and even had much influences on Chinese Acupuncture and Moxibustions growth, exporting Hwang-Je-Ne-Kyong to Chinese Song dynasty. 3. About the education system of medicine, Doo-Jong Kim viewed that Koreas medicine was only a copy of Shilla dynastys which was based on Chinese Tang dynastys, taking the medical examination curriculum as an example. The fact is that Tangs medical curriculum was three, Bon-Cho, Kab-Ul, Maek-Kyong, Shilla had seven, Bon-Cho-Kyong, Kab-Ul-Kyong, So-Moon-Kyong, Chim-Kyong, Maek-Kyong, Myong-Dang-Kyong, Nan-Kyong, and Korea had ten, So-Moon-Kyong, Kab-Ul-Kyong, Bon-Cho-Kyong, Myong-Dang-Kyong, Maek-Kyong, Dae-Kyong-Chim-Kyong, Nan-Kyong, Ku-Kyong, Ryu-Yon-Ja-Bang, So-Kyong-Chang-Jeo-Ron. Simply considering this, it is so clear that Koreas medical curriculum was much more upgraded one than that of China. 4. About the examination system for civil service, Doo-Jong Kim expressed that Shilla dynasty did not have such system, and only expounded knowledge of Shilla medicine, In case of China, Tang danasty Hyang-Kong was only a qualification test for civil service, which the result was completely dependent on applicants social status, Song danasty examination system was composed of three steps of Hyang-Si, Sung-Si, Jeon-Si (See Note1), but it stuck to formality by having Jeon-Si of anti-fraudulence use. On the other hand, examination system for civil service in Korea dynasty started in 958 by an advice of Ssang-Ki, Chin-Si in 977 and K대-Ja-Si (See Note 1), a kind of Hyang-Si, in 1024., Three steps of examination system made employment for civil service strictly fair, Moreover, it was possible for offsprings of concubine to be an applicant. These easily explain that the examination system of Korea dynasty was more upgraded one than that of China, Tang ＆ Song dynasty. Hyang-Si : Exam in local area Sung-Si : Exam in province for those who passed Hyang-Si Jeon-Si : Exam held with Koea Kings supervision for those who passed Hyang-Si Keo-Ja-Si : Selective exam in local area like Hyang-Si. From the reasons above, it is clear that Doo-Jong Kim was much biased by flunkeyism through Japanese colonialisam and expressed his view on Korea Medical History based on such theory of heteronomy and stasis. Moreover, without rigid historical evidence on records, he distored the fact by translating incorrectly on his purpose. Therefore, Doo-Jong Kims Korean Medical History must be reevaluated through rigid historical research and his mistranslation should be corrected.