• Economic and Environmental Geology
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• v.19 no.2
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• pp.153-163
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• 1986

Paleomagnetic and geological studies of volcanic and sedimentary rocks of Jeju Island have been carried out to determine the position of virtual geomagnetic pole(VGP), and to estimate the geological sequence and their age. As a result of paleomagnetic studies, the reversal polarities are measured in the Sanbangsan trachyte and Hwasun formation, and the normal are the rest. In case of normal polarity, the mean values of declination and inclination are $2.3^{\circ}$ and $48.4^{\circ}$, respectively, and the average value of VGP is $85.4^{\circ}N$ and $79.9^{\circ}W$. The locations of VGP's are coincident with those obtained from world-wide Plio-Pleistocene rocks. The Hwasun formation and Seongsan formation which have been known to be sedimented in the similar time in the 2nd-stage of volcanic eruption, possess reversal and normal polarities, respectively. This fact brings about the result that two formations should be separated in a sense of geological sequence. Consequently, the geological sequence of the 2nd-stage of volcanic eruption is Pyoseonri basalt-Seoguipo hawaiite-Hwasun formation-Seongsan formation-Jungmun hawaiite-Sanbangsan trachyte. Referring to the paleomagnetic studies and the previous and present geological studies, Seoguipo formation corresponds to the Gauss normal epoch, the 2nd-stage of volcanic eruption to Matuyama reversed epoch, and the 3rd-, 4th-, and 5th-stages to Brunhes normal epoch. Therefore, the Seoguipo formation is mostly sedimented during late Pliocene and/or presumably extended to the early Pleistocene. The rocks of the 2nd- to 5th-stage are formed later than this.

• Economic and Environmental Geology
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• v.27 no.1
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• pp.49-63
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• 1994

Paleomagnetic study of Tertiary rocks in Pohang area has been carried out to determine the characteristic directon of natural remanent magnetization, the position of paleomagnetic pole, the stratigraphic correlation, and the tectonic movement. A total of 196 specimens was collected from 5 sites in the Pohang Basin, 19 sites in the Janggi Basin, and 10 sites in the Eoil Basin, respectively. The mean declination and inclination of 4 sites (3 sites in the Yonil Group and 1 site in the Yonil Basalt) are $-3.2^{\circ}$ and $54.3^{\circ}$, and yield the paleomagnetic pole position $86.9^{\circ}N$ and $7.7^{\circ}E$. These are the characteristic direction and pole position of Miocene Epoch by comparison with contemporary Eurasian and Chinese data. The characteristic direction and pole position of remaining 30 sites are $47.6^{\circ}$ and $57.5^{\circ}$, and $52.3^{\circ}N$ and $201.5^{\circ}E$, respectively. These show clockwise rotation of $50.8^{\circ}$ with respect to the Miocene ones resulted by a tectonic movement before the deposition of the Hakjeon Formation of the Yonil Group about 15~16 Ma in the study area. The mechanism of the clockwise rotation is considered to be the dextral movement of the Yangsan Fault presumably caused by the opening of the East Sea. The Yonil Basalt is reclassified into pre- and post-deposition of the Yonil Group, i.e. the former is early Miocene and the latter late Miocene.

• Economic and Environmental Geology
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• v.26 no.3
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• pp.395-401
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• 1993

Lower Ordovician rock samples were collected from 23 sites located at the Okcheon non-metamorphic zone, near Taeback and Yeongweol areas, southern part of the Korean Peninsula. A characteristic magnetic component was obtained from four sites. This stable direction ($Dm=-19.4^{\circ}$, $Im=24.1^{\circ}$) which is carried by hematite of very high temperature $679^{\circ}C$), successfully pass both of reversal test and paleopole reliability test, and is regarded as a primary direction. The remagnetized components can be divided into three on the basis of their characteristic directions and magnetic minerals. The first which is carried by hematite, magnetite and pyrrhotite, is widely found at the whole sites. It shows syn- or post-tectonic remagnetization according to strongly negative fold test and distribution between Mesozoic and present field directions. The second, in situ, is distinguishable from the present field direction. After bedding correction, it is identical to Late Triassic to Early Jurassic direction. Its magnetic carrier is considered to be a single component hematite, which may be acquired by pre-tectonic CRM in the Okcheon orogenic zone. The third, which is carried by magnetite and hematite, is characterized by stable reversed direction. These minerals may be acquired by the thermal or chemical process in unknown period. Paleopole position is $169.2^{\circ}E$ in longitude and $59.9^{\circ}S$ in latitude, which indicates that the study area was located at $12.6^{\circ}S$ in paleo-latitude and belonged to northern end of the Gondwana in Early Ordovician.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.33 no.2
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• pp.123-129
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• 2015

The Kalman filter has been widely used in the kinematic GPS positioning due to its flexibility and efficiency in computational points of view. At the same time, the relative positioning technique also provided the high precision positioning results by removing the systematic errors in the measurements significantly. However, the positioning quality may be degraded following to longer in baseline length. For this case, it is required that the remaining atmospheric effects, such as double-difference ionospheric delay and zenith wet delay, should be properly modeled by examining the characteristics of the stochastic processes. In general, atmospheric effects are estimated with the assumption of random walk, or the first-order Gauss-Markov stochastic process, which requires the precise modeling on the corresponding process noises. Therefore, we determined and provided the parameters for modelling the process noises for atmospheric effects. The auto-correlation functions are empirically determined at first, and then the parameters are extracted from the empirical auto-correlation function. In fact, the test results can be either applied directly, or used as guidance values for the modeling of process noises in the kinematic GPS positioning.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.173-175
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• 2002

지하수함양은 크게 강우 중에 침투되는 자연함양, 하천 또는 저수지에서 침투되는 지표수 함양, 인위적으로 물을 지하로 침투시키는 인공함양 등이 있는데, 본 연구에서는 강우에 의해 지하로 침투되는 자연함양율을 구하기 위하여 다음 두 가지 방법을 이용하여 지하수함양율을 산출하고자 하였다. 첫 번째 누적강수량과 지하수수위곡선을 이용하는 방법(문상기, 우남칠, 2001)은 강우기간 중 누적강수량을 고려하여 지하수위변화로부터 지하수함양율을 추정하고, 두 번째 무강우기간 동안의 지하수위감수곡선을 이용하는 방법(최병수, 안중기, 1998)은 토양특성, 증발산을 배재한 상태에서 무강우기간의 지하수위감쇠곡선으로부터 함양량을 추정한다. 즉 같은 지역에서 선행강우기간 중 지하수침투가 시작되는 강우량과 어떤 시점에서의 강우기간 중 지하수침투가 시작되는 강우량의 차이가 토양함수조건에 따라 다를 수 있으나 평균개념으로 볼 때 그 차이가 무시될 수 있다고 가정하여 토양특성을 배재하고, 지하수수위가 지표에서 1.0~l.5m이상 되면 지하수로부터의 증발산은 무시될 수 있다고 가정하고 있다. 연구지역은 충청북도 청원군 북일면과 북이면에 위치하며, 지하수위 장기관측은 암반관정과 충적관정을 두 지점에 설치하여 총 4개의 관측정에서 지하수위자동측정기 Orphimedes (기포식수위계, OTT Hydrometrie사 제작)로 1시간 간격으로 지하수위변화를 기록하였다(그림1, 그림2). 강우량은 현장에서 자기우량계(모델명 : HGR-200, SEBA Hydrometrie사 제작)를 설치하여 직접 측정하였고, 자료가 유실된 기간은 청주기상대 자료로 보완하였다. 그러나 본 연구지역은 면적이 32.35$\textrm{km}^2$이고 1998년까지 개발된 기설관정의 개수가 무려 1,547여공으로 단위면적당 관정수는 48여공/$\textrm{km}^2$로 다른 지역에 비해 관정이 밀집되어 있어 지하수연간사용량을 무시할 수 없다. 그림2에서 보는 바와 같이 주변관정들의 양수로 인하여 관측정에서의 지하수위변화가 영향을 받는 것을 알 수 있다. 그러므로 본 연구지역을 대상으로 추정한 함양율은 지하수이용에 따른 지하수위하강에 대한 보정을 할 필요가 있으며 지하수이용실태조사를 추가로 하여 그 이용량만큼을 지하수함양량에 더하여야 할것이다.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.03a
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• pp.80-80
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• 2011

최근 환경과 건강에 대한 관심이 증대되면서, 천연 섬유를 소재로 사용한 최종 제품 역시 고급화 및 고기능화되고 있는 추세이며 섬유항균가공분야에 있어서도 천연 추출물을 이용한 항균가공이 주목을 받고 있다. 현재 항균가공에 사용되고 있는 항균제는 일반적으로 합성항균제를 사용하고 있고 이는 거의 대부분 자극성 화합물로써 인체에 잠재적 유해요인이 될 수 있고 제조 및 가공과정에서 환경오염을 유발시키는 문제점도 발생되고 있다. 반면 천연추출물을 사용할 경우 합성물질에 비해 포름알데히드 검출 등의 인체 안정성의 불안이 적어 건강차원에서 그 인식이 점차 증대되고 있는 추세이다. 천연항균물질에는 chitosan이나 식물에서 추출된 천연항균물질 등이 있는데 특히 식물에서 추출된 천연항균물질은 피톤치드(phytoncide)라고 표현되고 있으며 이는 수목들이 해충이나 미생물 등으로부터 자기방어를 위해 공기 중으로 발산하는 방향성의 항생물질을 뜻하는 말이다. 본 연구에서는 식물 중에서 피톤치드 정유의 함량이 많다고 알려진 측백나무과의 편백나무 정유를 이용하였으며 편백나무 정유가 식물성 천연 오일형태이므로 가공 처리 시 물과 계면이 발생되기 때문에 HLB(Hydrophilic Lipophlic Balance) 조건에 따른 최적 유화조건을 선정하였으며 편백나무 정유를 이용한 면직물의 항균 기능 부여를 위한 시험으로 편백나무 정유 처리 농도에 따른 항균성을 평가해 보고자 하였다. 실험 결과 편백나무 정유는 HLB 15이상 계면활성제 사용 시 물에 용해성이 좋고 안정된 에멀젼 상태를 보였으며 제조된 편백나무 정유 가공액 5%이상 처리 시 Staphylococcus aureus과 Klebsiella pneumoniae의 99.9% 정균감소율을 나타내었다.

• Journal of Environmental Science International
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• v.24 no.1
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• pp.117-131
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• 2015

Purpose: In this study a pilates exercise program using self-efficacy sources was provided for women 65 years of age or older and the effects on physical fitness, body composition, depression, self-efficacy, and health-related quality of life were tested. Methods: A quasi-experimental study employing a nonequivalent control group, pre-post design was conducted. The subjects consisted of 30 older women in the experiment group and 30 in the comparison group. The intervention was conducted twice a week for a period of 12 weeks. During this period, the pilates exercise program using self-efficacy sources (health education, phone coaching, mentoring, checking homework, recreation) were provided in the experiment group and pilates exercise program were offered in the comparison group. Chi-square test, independent t-test, ANCOVA were used for data analysis. Results: Following completion of the program, upper muscle strength (F=4.131, p=.047), low muscle strength (F=5.558, p=.022), upper flexibility (F=5.252, p=.026), static balance (F=5.957, p=.018), dynamic body balance & agility(F=18.971, p<.001), endurance(F=10.058, p=.002), muscle mass (F=5.748, p=.020), depression (F=4.493, p=.038), Self-efficacy (F=33.853, p<.001), and Health-related quality of life(F=5.586, p=.022) were significantly better in the experimental group. Conclusion: Findings from this study indicate that the pilates exercise program using self-efficacy sources are effective in enhancing physical fitness, body composition, self-efficacy and health-related quality of life and in decreasing depression for female elders and could therefore be regarded as positive program for promotion of physical and mental health for older women.

• Journal of Korean Library and Information Science Society
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• v.45 no.3
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• pp.321-348
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• 2014

The purpose of this study is to examine in depth the personal experience of Pre-Service Librarian Teacher during Student Teaching Practice. This helps us understand the overall process and diverse environment of Student Teaching Practice. We conducted in depth interview with participants who had recently experienced. and data analysis was undertaken using the phenomenological method devised by Giorgi. The significance of Pre-service Teacher Librarian experiences during Student Teaching Practice can be summarized in five categories as follows: 'the formation of Pre-service Librarian teacher's awareness about library and librarian through growth process', 'concretization and Strategy Implementation about Career Planning', 'Self-growth Need through experience of student teaching practice', 'Understanding of Organizational Culture Perception of Communication', 'Face reality about library and librarian'. These constituents can be understood in the context of time sequence. The result of this study may contribute for improving the overall environment at Student Teaching Practice.

• Economic and Environmental Geology
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• v.31 no.4
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• pp.311-324
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• 1998

Paleomagnetic study is carried out to investigate the possibility of remagnetization by dikes in the Cretaceous Gyeongsang Basin. We selected a site for a contact test as a preliminary study, and collected 41 core samples (7 from andesitic dike, 17 from sedimentary rock on the left side of dike and 17 from sedimentary rock on the right side). Magnetite was responsible for the remagnetization based on microscopic observation and demagnetization analysis. Although the increasement of magnetic susceptibility appears on both sides about 100 cm from the dike, the increment of NRM intensity was obtained from the specimens on the left side only. This is interpreted that the size of magnetite newly formed is dominated by superparamagnetic grains in the right side, but by larger than single-domain grains in the left. Reversed polarity component remagnetized by intrusion of dike was also found only for core samples from 116 cm left side of dike but abscent from right side indicating the remagnetization by the dike depends on the geometric shape and width of the dike, which is supported by field observations. The content of epidote is well correlated with remagnetization, and indicates the hydrothermal alteration/metameorphism was activated by the intrusion. We concluded that the above evidences in this study further support thermally-activated chemical origin of the remagnetization with meager contribution of contact metamorphism, and that any significant evidence of regional-scaled remagnetization was not found in the study area.

• Economic and Environmental Geology
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• v.31 no.1
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• pp.31-43
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• 1998

A total of 469 granitic samples were collected from 44 sites in the Ulsan fault area, southeast Korea. According to the previous petrographic studies, the granitic rocks have been divided into four groups (Hornblende biotite granodiorite, Hornblende granite, Biotite granite and Alkali-feldspar granite). NRM intensities, values of low field magnetic susceptibility, and magnetic behaviors during stepwise demagnetization experiments suggest rather a three-fold classification: In this scheme, Hornblende granite and Biotite granite are grouped together, as they did not show any significant differences in magnetic characteristics. Based on the Ishihara (1979)'s criterion, Alkali-feldspar granite is classified as ilmenite-series granite, whereas others are classified as magnetite-series granite. In the eastern part of the study area including the Tertiary basin area, declinations of site-mean characteristic remanent magnetizations (ChRMs) show clockwise deflection of more than 30 from the reference direction of east Asia. Both along and in the adjacent region of the Ulsan fault-line, however, no deflection of remanent direction was observed. A boundary line between the deflected and undeflected site-mean ChRMs is defined in this study, which runs roughly parallel to the Ulsan fault-line at the distance of about 6km eastward from the fault-line. We suggest that this newly found boundary line, which we call Yonil tectonic line, released dextral simple shear stress acted in the southeastern part of the Korean peninsula during the opening stage of the East Sea in the Early Cenozoic.