• Journal of Radiation Protection and Research
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• v.30 no.3
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• pp.113-119
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• 2005

The computed tomogrpahy(CT) provides a high quality in images of human body but contributes to the relatively high patient dose. The frequency of CT examination is increasing and, therefore, the concerns about the patient dose are also increasing. In this study the experimental determination of patient dose was performed by using a physical anthropomorphic phantom and thermoluminescent dosimeter(TLD). The measurements were done for the both axial and spiral scan mode. As a result the effective doses for each scan mode were 17.78mSv and 10.01 mSv respectively and the fact that the degree of the reduction in the patient dose depends on the pitch scan parameter was confirmed. The measurement methods suggested in this study can be applied for the reassessment of the patient dose when the technique in CT equipment is developed or the protocol for CT scanning is changed.

• The Journal of Engineering Geology
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• v.26 no.2
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• pp.277-290
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• 2016

Deep geological cross-sectional data is generally not common nor easy to construct, because it is expensive and requires a great deal of time. As a result, geological interpretations at depth are limited. Many scientists attempt to construct geological cross-sections at depth using geological surface data and geophysical data. In this paper, we suggest a method for constructing cross-sections from limited geological surface data in a target area. The reason for this study is to construct and interpret geological cros-sections at depth to evaluate heat flow anomaly along the Yangsan fault. The Yangsan Fault passes through the south-eastern part of the Korean Peninsula. The cross-section is constructed from Sangbukmyeon to Unchonmyeon passing perpendicularly through the Yangsan Fault System trending NW-SE direction. The geological cross-section is constructed using the following data: (1) Lithologic distributions and main structural elements. (2) Extensity of sedimentary rock and igneous rock, from field mapping. (3) Fault dimension calculated based on geometry of exposed surface rupture, and (4) Seismic and core logging data. The Yangsan Fault System is composed of the Jain fault, Milyang fault, Moryang fault, Yangsan fault, Dongnae fault, and Ingwang fault which strike NNE-SSW. According to field observation, the western section of the Yangsan fault bounded by igneous rocks and in the eastern section sedimentary rocks are dominant. Using surface fault length we infer that the Yangsan Fault System has developed to a depth of kilometers beneath the surface. According to seismic data, sedimentary rocks that are adjacent to the Yangsan fault are thin and getting thicker towards the east of the section. In this study we also suggest a new method to recognize faults using core loggings. This analysis could be used to estimate fault locations at different scales.

• Journal of the Korean Electrochemical Society
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• v.16 no.4
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• pp.217-224
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• 2013

In this paper, we have investigated the characteristics of cyclic voltammetry of a self-assembled mono-layer(SAM) electrode which was modified by 3-Mercaptopropionic acid (3-MPA) on gold nanoparticle(AuNP)-deposited electrode. Also, the transport phenomena of electrons and ions around the electrode have been analyzed. The governing equation and its boundary conditions by adopting the semi-infinite diffusion model were formulated for the mass-transfer dominant system. In order to obtain the numerical solutions of cyclic voltammetry(CV) on SAM electrodes, MATLAB program was implemented by applying the explicit finite difference method. Resulting CV program for the SAM-modified electrode was verified in good agreements with the experimental CV results for the 3-MPA on AuNP electrode.

• Journal of the Korean Society of Radiology
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• v.82 no.4
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• pp.936-942
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• 2021

Langerhans cell histiocytosis (LCH) is a rare condition that usually occurs in children and commonly affects the skeletal system. It is extremely rare in adults, especially in the clavicles. In this report, we describe a pathologically confirmed case of LCH in the clavicle of a 50-year-old male. We report various radiological findings, such as plain radiography, CT, MR, and PET-CT, along with a review of the literature.

• Korean Journal of Heritage: History & Science
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• v.49 no.4
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• pp.4-21
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• 2016

Until now, most studies regarding stone pagodas of the Honam region have been about stone pagodas with Baekje style because it was the territory of Baekje. However, after reviewing the designated cultural properties, I found that among the 94 stone pagodas in the Honam region there are 15 stone pagodas with Baekje style built in the Goryeo Dynasty and 34 stone pagodas with Silla style. So far, most research efforts have been concentrating on stone pagodas with Baekje style. Through a review of stone pagodas with Silla style, I sought to reveal new aspects of the pagodas in the Honam region. After reviewing the placement of pagodas, I found stone pagodas with Silla style were built mostly in South Jeolla Province during the Unified Silla period. However, in the Goryeo Dynasty stone pagodas with Silla style were erected throughout the Honam region. This shows enhanced Buddhist control over the Honam region than in the previous period. It can be verified especially in Gimje, Jeongeup, Sunchang, Damyang, Yeongam, and Gangjin, where stone pagodas with Baekje style and stone pagodas with Silla style coexist. The types of stone pagodas with Silla style in the Honam region can be divided into two. There are 21 pagodas with two-story foundation, and 12 with single foundation. They seem to have inherited characteristics of the two-story foundation of Silla pagodas. Two pagodas with single foundation were made of a single rock or natural rock for lower foundation. Regarding the body of the pagoda, there are 21 three-story pagodas and 12 five-story pagodas. 25 pagodas have first floors made of a single rock. These are likely to be in the tradition of Silla pagodas. However, the lower part of the roof stones vary as there are three, four, or five-tiered ones. Overall, 12 out of 16 pagodas with middle column in foundation, and 15 out of 21 three-story pagodas are located in South Jeolla Province. This proves that stone pagodas in the South Jeolla Province well maintained the tradition of Silla and became popular.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2001.04a
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• pp.66-73
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• 2001

Yangsan fault in the southeastern part of Korean peninsula has been locally reactivated along a prexisted fault during the late Pleistocene time. Geomorphological evidence of the reactivation is revealed at the northern segment(Yugye-ri, Tosung-ri areas) of the Yangsan fault. The reactivation is distinctively characterized by fault gouge and fracture zone with high frequency in the Yugye-ri area. Obique slip separation of the area is about three meters of the middle terrace. The cumulative vertical displacement is recognized after the formation of the middle terrace. Age of the reactivated faulting is constrained to during the formation of dissected valley deposits. Average vertical slip based on paleo-event is inferred to about 0.5-0.7 meter in this area.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1998.10a
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• pp.235-240
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• 1998

Quaternary fault movement of the Ulsan fault system was interpreted by aenal photograph, field survey and trench excavation. The geomorphological evidences associated with active fault are clearly shown at Cheonbuk-myeon area, northern part of Ulsan fault system. In the trench wall one reverse fault(N 50$^{\circ}$E, 70$^{\circ}$E) is identified between basement rock (Miocene mudstone) and gravel deposits Another thrust fault (NS) extends up to the red and light brown soil layers. Middle terrace surface shows cumulative vertical displacements of about 3 to 7 m. The horizontai displacement of the red soil by faulting event is about 1.8 to 2.4m. The age of the fault activity is younger than that of the soil layer, which is roughly estimated to be late Quaternary (about 100Ka)

• Economic and Environmental Geology
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• v.52 no.5
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• pp.323-336
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• 2019

The Mesozoic activity on the Korean Peninsula is mainly represented by the Triassic post-collisional, Jurassic orogenic, and Cretaceous post-orogenic igneous activities. The diversity of mineralization by each geological period came from various geothermal systems derived from the geochemical characteristics of magma with different emplacement depth. The Cretaceous metallic mineralization has been carried out over a wide range of time periods from ca. 115 to 45 Ma (main stage; ca. 100 to 60 Ma) related to post-orogenic igneous activity, and spatial distribution patterns of most metal deposits are concentrated along small granitic stocks. The late Cretaceous metal deposits in the Gyeonggi and Yeongnam massifs are generally distributed along the boundary among the Gongju-Eumseong fault system and the Yeongdong-Gwangju fault system and the Gyeongsang Basin, most of them are in the form of a distal epithermal~mesothermal Au-Ag vein or a transitional mesothermal Zn-Pb-Cu vein. On the other hand, diverse metal commodities in the Taebaeg Basin, the Okcheon metamorphic belt and the Gyeongsang Basin are produced from various deposit types such as skarn, carbonate-replacement, vein, porphyry, breccia pipe, and Carlin type. In the late Cretaceous metallic mineralization, various mineral deposits and commodities were induced not only by the pathway of the hydrothermal solution, but also by the diversity of precipitation environment in the proximity difference of the granitic rocks. The diversity of these types of Cretaceous deposits is fundamentally dependent on the geochemical characteristics such as degree of differentiation and oxidation state of related igneous rocks, and ore-forming fluids generally exhibit the evolutionary characteristics of intermediate- to low-sulfur hydrothermal fluids.

• The Journal of the Petrological Society of Korea
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• v.27 no.3
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• pp.109-120
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• 2018

The distributional characteristics of fault segments in Cretaceous and Tertiary rocks from southeastern Gyeongsang Basin were derived. The 267 sets of fault segments showing linear type were extracted from the curved fault lines delineated on the regional geological map. First, the directional angle(${\theta}$)-length(L) chart for the whole fault segments was made. From the related chart, the general d istribution pattern of fault segments was derived. The distribution curve in the chart was divided into four sections according to its overall shape. NNE, NNW and WNW directions, corresponding to the peaks of the above sections, indicate those of the Yangsan, Ulsan and Gaeum fault systems. The fault segment population show near symmetrical distribution with respect to $N19^{\circ}E$ direction corresponding to the maximum peak. Second, the directional angle-frequency(N), mean length(Lm), total length(Lt) and density(${\rho}$) chart was made. From the related chart, whole domain of the above chart was divided into 19 domains in terms of the phases of the distribution curve. The directions corresponding to the peaks of the above domains suggest the directions of representative stresses acted on rock body. Third, the length-cumulative frequency graphs for the 18 sub-populations were made. From the related chart, the value of exponent(${\lambda}$) increase in the clockwise direction($N10{\sim}20^{\circ}E{\rightarrow}N50{\sim}60^{\circ}E$) and counterclockwise direction ($N10{\sim}20^{\circ}W{\rightarrow}N50{\sim}60^{\circ}W$). On the other hand, the width of distribution of lengths and mean length decrease. The chart for the above sub-populations having mutually different evolution characteristics, reveals a cross section of evolutionary process. Fourth, the general distribution chart for the 18 graphs was made. From the related chart, the above graphs were classified into five groups(A~E) according to the distribution area. The lengths of fault segments increase in order of group E ($N80{\sim}90^{\circ}E{\cdot}N70{\sim}80^{\circ}E{\cdot}N80{\sim}90^{\circ}W{\cdot}N50{\sim}60^{\circ}W{\cdot}N30{\sim}40^{\circ}W{\cdot}N40{\sim}50^{\circ}W$) < D ($N70{\sim}80^{\circ}W{\cdot}N60{\sim}70^{\circ}W{\cdot}N60{\sim}70^{\circ}E{\cdot}N50{\sim}60^{\circ}E{\cdot}N40{\sim}50^{\circ}E{\cdot}N0{\sim}10^{\circ}W$) < C ($N20{\sim}30^{\circ}W{\cdot}N10{\sim}20^{\circ}W$) < B ($N0{\sim}10^{\circ}E{\cdot}N30{\sim}40^{\circ}E$) < A ($N20{\sim}30^{\circ}E{\cdot}N10{\sim}20^{\circ}E$). Especially the forms of graph gradually transition from a uniform distribution to an exponential one. Lastly, the values of the six parameters for fault-segment length were divided into five groups. Among the six parameters, mean length and length of the longest fault segment decrease in the order of group III ($N10^{\circ}W{\sim}N20^{\circ}E$) > IV ($N20{\sim}60^{\circ}E$) > II ($N10{\sim}60^{\circ}W$) > I ($N60{\sim}90^{\circ}W$) > V ($N60{\sim}90^{\circ}E$). Frequency, longest length, total length, mean length and density of fault segments, belonging to group V, show the lowest values. The above order of arrangement among five groups suggests the interrelationship with the relative formation ages of fault segments.

• 전기의세계
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• v.38 no.8
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• pp.19-25
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• 1989

현재 전세계적으로 퍼져있는 NMR-CT 시스템의 수를 살펴보면 약 370여기가 설치.운영되고 있으며 앞으로 계속 늘어날 전망이다. 국내에서는 1988 한국과학기술원과 금성통신에 의해 자체 개발된 2.0 Tesla 강자장 시스템이 최초로 서울대학병원에 설치 가동된 이래 여러병원에서 시스템들이 설치중에 있다. 첨단의로 진단장치로서의 핵자기 공명 영상법은 그 영상을 통하여 기존의 진단 장치보다 우월함을 증명하고 있으며 초음파 검사나 동위원소 검사 및 X선 전산화 단층 촬영술들을 장점을 두루 지니면서 그 영상법의 다양성 때문에 앞으로의 연구 및 발전에 대한 전망은 아주 밝다고 할 수 있다. 따라서 앞으로의 종합 영상 의료 진단 장치는 이 NMR-CT가 중심이 되어 발전할 것이라고 단언해도 무리한 생각은 아닐 것이다.