• The Journal of the Petrological Society of Korea
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• v.21 no.2
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• pp.151-171
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• 2012

The Permo-Triassic Songrim orogeny in the Korean peninsula was a major tectonic event involving complicated continental collisions at the eastern margin of Eurasia. Based on the previous studies on the metamorphic and deformations features of the Songrim orogeny, this paper presents metamorphic and structural characteristics and timing of the Songrim orogeny in the Taebaeksan basin, and discuss about correlation of the tectono-metamorphic evolution of the Taebaeksan basin with the Okcheon basin and the Imjingang belt with a combined analysis of bulk crustal shortening direction, metamorphic P-T and T-t (time) paths. The metapelites in the Pyeongan Supergroup in the northeastern margin of the Taebaeksan basin have experienced lower-temperature/medium-pressure (LT/MP) regional metamorphism followed by high-temperature contact metamorphism due to the Jurassic granite intrusion. The earlier LT/MP regional metamorphism produced two loops of clockwise P-T-d (deformation) paths combined with four deformation events ($D_1-D_4$). The first loop concomitant with $D_1$ and $D_2$ occurred at $400-500^{\circ}C$, 1.5-3.0 kbar, and related with growth of syn-$D_1$ chloritoid and andalusite, post-$D_1$ margarite, Ca-rich syn-$D_2$ or post-$D_2$ plagioclase. The second loop accompanying $D_3$ and $D_4$ occurred at $520-580^{\circ}C$, 2.0-6.0 kbar, and associated with the growth of syn-$D_3$ garnet and staurolite, and syn-$D_4$ and/or post-$D_4$ andalusite porphyroblasts. Furthermore the syn-$D_1$ chloritoid and andalusite porphyroblasts grew during E-W bulk crustal shortening, whereas the syn-$D_3$ garnet and staurolite, and the syn-$D_4$ and/or post-$D_4$ andalusite porphyroblasts have grown under N-S bulk crustal shortening. The similarity in the characteristics and timing of the metamorphism and bulk crustal shortening directions between the Okcheon and Imjingang belts suggest that the peak metamorphic conditions tend to increase toward the western part (Imjingang belt and southwestern part of the Gyeonggi Massif) from the eastern part (Taebaeksan basin). The E-W bulk crustal shortening influenced the eastern part of the Okcheon belt, whereas the N-S bulk crustal shortening resulted in strong deformation in the Imjingang and Okcheon belts. Consequently, the Permo-Triassic Songrim orogeny in the Korean peninsula is probably not only related to collision of the North and South China blocks, but also to the amalgamation of terrane fragments at the eastern Eurasia margin (e.g., collision of the Sino-Korean continent and the Hida-Oki terrane).

• The Journal of the Petrological Society of Korea
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• v.25 no.3
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• pp.211-230
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• 2016

Detailed mapping along the Keumwang fault reveals a complex history of multiple brittle reactivations following late Jurassic and early Cretaceous ductile shearing. The fault core consists of a 10~50 m thick fault gouge layer bounded by a 30~100 m thick damaged zone. The Pre-cambrian gneiss and Jurassic granite underwent at least six distinct stages of fault movements based on deformation environment, time and mechanism. Each stage characterized by fault kinematics and dynamics at different deformation environment. Stage 1 generated mylonite series along the Keumwang shear zone by sinistral ductile shearing during late Jurassic and early Cretaceous. Stage 2 was a mostly brittle event generating cataclasite series superimposed on the mylonite series of the Keumwang shear zone. The roundness of pophyroclastes and the amount of matrix increase from host rocks to ultracataclasite indicating stronger cataclastic flow toward the fault core. At stage 3, fault gouge layer superimposed on the cataclasite generated during stage 2 and the sedimentary basins (Umsung and Pungam) formed along the fault by sinistral strike-slip movement. Fragments of older cataclasite suspended in the fault gouge suggest extensive reworking of fault rocks at brittle deformation environments. At stage 4, systematic en-echelon folds, joints and faults were formed in the sedimentary basins by sinistral strike-slip reactivation of the Keumwang fault. Most of the shearing is accommodated by slip along foliations and on discrete shear surfaces, while shear deformation tends to be relatively uniformly distributed within the fault damage zone developed in the mudrocks in the sedimentary basins. Fine-grained andesitic rocks intruded during stage 4. Stage 5 dextral strike-slip activity produced shear planes and bands in the andesitic rocks. ESR(Electron Spin Resonance) dates of fault gouge show temporal clustering within active period and migrating along the strike of the Keumwang fault during the stage 6 at the Quaternary period.

• Journal of the Korean Society for Nondestructive Testing
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• v.25 no.5
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• pp.343-349
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• 2005

In this research, the fiber Bragg grating sensors with long gauge for displacement measurement in the long distance is developed and tested. The sensors show an accuracy and a capability for displacement measurement oin long distance. Monitoring using static logger of system of FBG sensor with strained optical fiber shows the capability of measurement in the harsh environment such as strong wind. Measurement of long distance displacement by optical fiber sensor if use $250{\mu}m$ optical fiber and impose some strong pre-tension shows possibility in monitoring of nuclear containment structure.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.8
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• pp.3745-3751
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• 2011

In this study flexural strength of damaged concrete beams reinforced by CFS is analysed. Nonlinear section analysis is used to include stress status of tension bars and compressive concrete under loads acting on the original member at the time of strengthening. Calculated flexural strength is compared with Sin-Hong formula which is frequently used in CFS reinforcement design. Nonlinear analysis with variation of the number of strengthening CFS, the ratio of tensile reinforcement, the ratio of section dimension shows that the flexural strength of CFS reinforced beams much depends on reinforcing stage. From the result of this analysis, the flexural strength of CFS reinforced concrete beam is reduced according to the magnitude of pre-loaded service loads.

• Journal of the Earthquake Engineering Society of Korea
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• v.2 no.2
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• pp.45-55
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• 1998

Although a number of methods have been proposed to predict the liquefaction potential, few methods have been developed by using the characteristic of material's microstructure. In this research, fundamental procedure is proposed for the assessment of liquefaction potential in saturated soils based on the Disturbed Sate Concept(DSC) model which can provide a unified constitutive model for the characterization of entire stress-strain behavior under cyclic loading. From this concept, the value of disturbance at threshold state (Critical Disturbance, $D_C$) in the deforming microstructure provides the basis for initial liquefaction. This method is verified with respect to data from Cyclic Truly Triaxial test for saturated Ottawa sand. Also, the relationship between liquefaction and initial confinig stress is defined using definition of $D_C$. It is believed that the new procedure for identifying liquefaction based on the DSC model can capture the behavior of liquefation, and as a result, it is shown to be on improvement over the available empirical procedures.

• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.2
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• pp.179-188
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• 2011

Steel structures have been allowed to have fatigue damage tolerance in fact. If it would be assessed whether fatigue crack is growing or not and How fast fatigue crack is propagating, we should make a rational decision on methods and a period of reinforcement in the maintenance. In this study, fatigue crack growth tests on two kinds of through-thickness cracked steel plates and a out-of-plane gusset welded joint were conducted to evaluate fatigue crack growth rate using the COD(Crack Opening Displacement), and COD measurement using strain gauges was examined to offer a practical method. As a result, we proposed a reasonable assessing method for fatigue crack growth rate using the COD and it was experimentally proved practical to estimate the COD through measuring strains.

• The Journal of the Korea Contents Association
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• v.12 no.2
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• pp.163-172
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• 2012

The hero is in the TV drama's long. TV drama Heroes historical blip on the public's desire to delegate to the body and its functions as an intensive, which have a specific period drama that soars like a hero's welcome and it is the communication between the viewer a sense of contemporary popular devices that can be separated. This study today, the various cultural areas which are becoming popular in Japan's historical hero 'Yoshitune' a heroic drama, the hero's narrative research stories In the analysis occupies an important place in the Joseph Campbell's 17 steps of heroic narrative, based on analysis achetype and adaptation. Campbell, 11 of the 17 stage dramas to apply different levels, and the omission of two steps, and shows a variation of the four stages, in order to relaunch the popular culture as the content selection and a constant strain was able to find out that you need.

• The Journal of the Petrological Society of Korea
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• v.19 no.2
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• pp.157-165
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• 2010

The age unknown Ogcheon metasedimentary rocks and the Jurassic Ogcheon granite (Jocgr) intruding it are distributed in the Ogcheon area, which is located in the central part of the Ogcheon Belt, Korea, This paper newly examines the timing of Honam shearing on the basis of the microstructural researches on time-relationship between the crenulation of Ogcheon metasedimentary rocks and the contact metamorphism by the intrusion of Jocgr. The D2 crenulation phase, which is defined by the microfolding of the S1 foliation in the metasedimentary rocks, is divided into two sub-phases. The one is a sub-phase of Early crenulation (D2a) which is included within old andalusite porphyroblasts, and the other is that of Late crenulation (D2b) which warps around the old andalusite. But they show the same dextral shear sense, the axial planes parallel to each other, and a single crenulation at outcrop scale. The contact metamorphism of andalusite-sillimanite type by the Jocgr occurred during the inter-phases of D2a and D2b, and crystallized the old andalusite masking the D2a crenulation and fibrous sillimanites replacing the D2a crenulation-forming muscovites. New andalusite porphyroblasts synkinematically grew in pressure shadows around the old andalusite or in its outermost mantles during the early stage of the D2b. The D2b occurred still continuously after the growth of the andalusite ceased (= later stage of the D2b). It indicates that the D2b occurred continuously during the period when the Ogcheon granite was still hot and cool. From this study, the crenulation history of Ogcheon metasedimentary rocks and the timing of Honam shearing would be newly established and reviewed as follows. (1) Early Honam shearing; formative period of Early crenulation, (2) main magmatic period of Jurassic granitoids; growth of the old andalusite and fibrous sillimanite by the intrusion of Jocgr, (3) main cooling period of Jurassic granitoids; formative period of Late crenulation related to Late Honam shearing, growth of the new andalusite in the early stage of D2b. Thus, this study proposes that the Honam shear movement would occur two times at least before and after the intertectonic phase which corresponds to the main magmatic period of Jurassic granitoids.

• The Journal of the Petrological Society of Korea
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• v.25 no.4
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• pp.389-400
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• 2016

The study area, which is located in the southeastern part of the Jirisan province of the Yeongnam massif, Korea, consists mainly of the Precambrian Sancheong anorthosite complex and the Jirisan metamorphic rock complex, the Mesozoic granitoids which intruded them. Several fracture sets with various geometric indicators, which determine their relative timing and shear sense, are well observed in the Sancheong anorthosite complex. The aim of this study is to determine the development sequence of extension fractures, the movement sense and development sequence of shear fractures in the Sancheong anorthosite complex on the basis of detailed analysis of their geometric indicators. This study suggests fracture system of the Sancheong anorthosite complex was formed at least through five different fracturing events, named as Dn to Post-Dn+3 phases. (1) Dn phase: extension fracturing event of NNW trend. The fracture set experienced the reactivations of dextral ${\rightarrow}$ sinistral shearing with the change of stress field afterward. (2) Dn+1 phase: extension fracturing event of (N)NE trend. The fracture set experienced the reactivations of sinistral ${\rightarrow}$ sinistral ${\rightarrow}$ dextral. (3) Dn+2 phase: extension fracturing event of NW trend. The fracture set experienced the activated of dextral shearing. (4) Dn+3 phase: extension fracturing event of N-S trend. (5) Post-Dn+3 phase: extension fracturing event of (E)NE trend. Dn deformation formed during the early Songnim orogeny. Dn+1 deformation formed during the late Songnim orogeny. Dn+2 deformation formed during the Daebo orogeny. Dn+3 deformation formed during the Bulguksa orogeny.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.83-83
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• 2019

아피오스(Apios americana Medikus)는 콩과에 속하는 덩굴성 식물로 원산지는 북미대륙 중동부로 알려져 있으며 지하부의 뿌리가 변형된 괴근 부위를 식용으로 하고 있다. 아피오스의 괴근은 건물당 단백질 함량이 16.5%로 감자에 비해 3배 가량 높고 지방산 함량은 4.2~4.6% 범위로 Linoleic acid가 주를 이루고 있다. 또한 감자에 비해 칼슘 함량이 10배 가량 높고 철분함량은 2배 가량 높아 기능성 건강식품으로 유망시되고 있다. 아피오스는 일교차가 큰 준고랭지역에서도 재배가능성이 높지만 최근의 기후변화에 따라 파종기의 저온피해 등으로 안정적인 입모율의 확보가 문제시 되고 있다. 준고랭지 지역에서 아피오스의 파종시기별 출현양상 및 수량성을 구명하기 위해 표고 500m의 허브산채시험장 포장에서 2018년 4월 25일, 5월 9일, 5월 16일, 5월 28일 4회 걸쳐 흑색비닐을 피복한 1줄 재배양식으로 아피오스 괴근을 파종하였다. 파종 후 30일, 50일간의 누적 출현율은 5월 18일 파종이 파종 30일 후 52.5%를 보였으며 같은 기간 동안의 유효적산온도는 $276.9^{\circ}C$ 범위였고, 5월 30일 파종에서 파종 후 30일간의 누적 출현율은 80.4%롤 보였으며 유효적산 온도는 $329.2^{\circ}C$를 나타냈다. 파종시기별 유효적산온도와 누적 출현율 간의 관계를 나타내는 관계식은 $y=0.1155{\times}1.0415$의 지수함수로 표현할 수 있었으며, 준고랭지(남원시 운봉읍)에서 2007~2017년까지의 10년간 평균기온을 기준으로 관계식을 적용한 결과 평년 기준 5월 18일 파종하는 경우 50일간 유효적산온도는 $390.5^{\circ}C$를 보였고 출현율은 55.6%가 기대되었으며 6월 11일에는 $601.5^{\circ}C$의 적산온도로 85.3%의 출현이 예상되었다. 파종시기별 총 괴근수는 5월 30일 파종에서 17.5개/주로 유의하게 적었으며 상품 괴근중 및 상품률도 유의하게 적은 경향이었고, 출현율을 고려한 단위면적당 상품 괴근수량은 5월 18일 파종에서 602.5㎏/10a로 가장 높았고 4월 25일 파종에서 348.6㎏/10a로 가장 낮아 준고랭지 아피오스 재배에서 적정 파종시기는 5월 중순으로 판단되었다.