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Manjang Cave of Twinrock Composition obtained by Fundamen Parameter Method in X-Ray Fluorescence Spectrometry (Fundamental Parameter 법에 의한 만장굴 용암 석주의 형광X선분석)

  • SAWA, ISAO
    • Journal of the Speleological Society of Korea
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    • v.21 no.22
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    • pp.17-56
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    • 1990
  • Cheju Island, which was formed by volcanic activity, is an oval in its shape with the major axis of 80km and the minor axis of 40km. The island holds in its heart Mt. Hanla rising 1,950m above the sea. Petrological study of this volcanic island has been made actively by Sang-Man Lee, Chong-Kwan won and Moon-Won Lee. The chronological measurements of the island by Chong-Kwan Won and Moon-Won Lee showed that it is composed of Sanbangsan trachytes and Backlokdam trachytes(25,000 year ago). These reports are based on the chemical analysis and the rediometric chronological measurements on the ground. However, there has been no reports about the inside of caves. We made an (composition) analysis of the inside of Manjang Cave by the fundamental parameter method in X-ray fluorescence spectrometry. The fundamental parameter method in X-ray fluorescence spectrometry is nondestructive analysis, and it enables us to make the values processed by a computer. The results obtained by this methods are as follows : SiO2(49%), Al2O3(17%), Fe2O3(13%), CaO(8.1%), MgO(5.5%), Na2O(3.6%), TiO2(2.1%), K2O(0.86%), P2O5(0.28%), and MnO(0.20%), respectively. The data obtained by the fundamental parameter method in X-ray fluorescence was compared with the data provided by Chong-Kwan and Moon-Won Lee. Our measurement was made by K-Ar-method in cooperation with T.ITAYA. The samples are of 30,000~420,000 year ago. The composition of the values of our underground analysis with the existing values obtained by the analyses on the ground produced new data about Cheju volcanic island.d.

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Chemical Composition Characteristics of Precipitation at Two Sites in Jeju Island

  • Kang, Chang-Hee;Kim, Won-Hyung;Lee, Won
    • Bulletin of the Korean Chemical Society
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    • v.24 no.3
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    • pp.363-368
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    • 2003
  • The major ionic components of precipitation collected at the 1100 Site of Mt. Halla and Jeju city have been determined. The reliability of the analytical data was verified by the comparison of ion balances, electric conductivities and acid fractions; all of their correlation coefficients were above 0.94. Ionic strengths lower than 104 M were found in 53% of the 1100 Site samples and 28% of the Jeju city samples. Compared with other inland areas, the wet deposition of Na+,ClandMg2+ was relatively larger, but that of NH+4,nssSO24(non-sea salt sulfate) and NO3 was lower. Especially the wet deposition increase of Ca2+ in the spring season supports the possibility of the Asian Dust effect. The acidification of precipitation was caused mostly by SO24andNO3 in the Jeju area, and the organic acids have contributed only about 7% to the acidity. The neutralization factors by NH₃were 0.47 and 0.48, and that of CaCO₃was 0.31 and 0.25 at the 1100 Site and Jeju city, respectively. Investigation into major influencing sources on precipitation components by factor analysis showed that the precipitation at the 1100 Site had been influenced mostly by an anthropogenic source, followed by soil and seawater sources. The precipitation at Jeju city was mainly influenced by oceanic sources, followed by anthropogenic and soil sources.

Landscape Design for the Culture.Welfare.Administration Complex of Youngin-City (용인시 문화복지행정타운 조경설계)

  • 김도경;김진국
    • Journal of the Korean Institute of Landscape Architecture
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    • v.30 no.3
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    • pp.46-56
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    • 2002
  • This landscape design proposal was presented to a design competition for the Culture.Welfare.Administration Complex of Yongin-City which was held by Yongin-City in December, 2001. The site is located at 68-19 Yukbuck-dong, Yongin-City, Kyunggi-do and has an area of 236,449m2. The judging criteria for landscape design set by the Yongin-City could be articulated as follows: an environment friendly design respecting the surrounding environment, a locale as a community center of Yongin-City, a resting place for the welfare of employees and visitors, and finally a place with diverse landscape elements reflecting the individual identity of each facility. This proposal chose the main design concept of this project as‘Nature meets City'. A grove of pine trees fragments the multi building complex, so that‘nature'was brought into the‘city'. A double ground system was introduced to respect the existing topography and to enhance the efficency of the land. This design proposal consists of four segments. Each segment has its own design theme. Outdoor space of this multi-purpose complex was designed with themes of nature, culture, welfare and administration. Space composition with grid and natural looking curvilinear lines was a design motive for this complex. The nature oriented planting design was introduced to respect the existing groves of Mt. Suksung. Specific species were chosen to follow its own spatial character in each space. An environmental sculpture called‘Dream Soaring'was placed in the middle of‘Citizen Plaza'. Its light and feather-looking shape symbolizes the vision of Youngin-City. At night people can watch the diverse color changes on its mirror-like surface.

Use of Portable Global Positioning System (GPS) Devices in Exposure Analysis for Time-location Measurement

  • Lee, Ki-Young;Kim, Joung-Yoon;Putti, Kiran;Bennett, Deborah H.;Cassady, Diana;Hertz-Picciotto, Irva
    • Journal of Environmental Health Sciences
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    • v.35 no.6
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    • pp.461-467
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    • 2009
  • Exposure analysis is a critical component of determining the health impact of pollutants. Global positioning systems (GPS) could be useful in developing time-location information for use in exposure analysis. This study compares four low cost GPS receivers with data logging capability (Garmin 60, Garmin Forerunner 201, GeoStats GeoLogger and Skytrx minitracker MT4100) in terms of accuracy, precision, and ease of use. The accuracy of the devices was determined at two known National Geodetic Survey points. The coordinates logged by the devices were compared when the devices were carried while walking and driving. The Garmin 60 showed better accuracy and precision than the GeoLogger when they were placed at the geodetic points. The Forerunner and Skytrx did not record when they were kept stationary. When the subject wore the devices while walking, the location of the devices differed by about 8 m on average between any two device combinations involving the four devices. The distance between the coordinates logged by the devices decreased when the devices were carried with their antennas facing the sky. All the devices showed similar routes when they were used in a car. All the devices except the Forerunner had satisfactory signal reception when they were worn and when they were carried in the car. The GeoLogger is less comfortable for the subject because of specific wearing requirements. This evaluation found that the Garmin 60 and the Skytrx may be useful in personal exposure analysis studies to record time-location data.

A Study on the Structure of Forest Community of Picea jezoensis Stands at Cheonwangbong Area, Jirisan(Mt.) (지리산국립공원 천왕봉지역 가문비나무림의 산림군집구조)

  • An, Hyun-Cheul;Kim, Gab-Tae;Choo, Gab-Cheul;Um, Tae-Won;Park, Sam-Bong;Park, Eun-Hee
    • Journal of Korean Society of Forest Science
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    • v.99 no.4
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    • pp.590-596
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    • 2010
  • To investigate and to compare the structure of Picea jezoensis forests at Chunwangbong area in the Jirisan National Park, 33 plots(400) were set up by a random sampling method. Dead individuals of Picea jezoensis trees were 15.6%, these were observed mainly in the upper-layer trees. A few seedlings of Picea jezoensis were found in this investigation area. This result indicates that Picea jezoensis might be gradually decreased in the future. Picea jezoensis stands were classified into two major groups by cluster analysis. There were strong positive correlations between Syringa reticulata and Acer pseudosieboldianum, Tripterygium regelii, Quercus serrata; Betula ermani and Lonicera maackii; Euonymus macropterus and Acer ukurunduense; Acer pseudosieboldianum and Tripterygium regelii, and relatively weak negative correlations were showed between Picea jezoensis and Abies koreana; Betula ermani and Acer ukurunduense; Acer pseudosieboldianum and Tripterygium regelii. Species diversity index(H') of investigated groups ranged from 1.0000 to 1.3010.

A Study on the Estimation of User′s Psychological Carrying Capacity in Mt. Chi-ak National Park Campsite (치악산국립공원 야영장의 이용자의 심리적 수용능력 추정에 관한 연구)

  • 권영선;이경재;송근준
    • Journal of the Korean Institute of Landscape Architecture
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    • v.16 no.1
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    • pp.1-12
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    • 1988
  • ^x This study was executed to measure the user's psychological carrying capacity in the National Park Campsite in the district of Temple Ku- Ryong as a model of analysis, which is made socio - psychological approach. The results are as follows ; 1. Since this Place hart a beautiful scenery and some cultural assets prosperties and lies near the metroplitan area, 67.5% of the user come from the district, such as Seoul, Inchon, Kyong - Ki Do, and the purpose of camping is to appease their stress and to promote friendly relationship one another. 2. Since most of the campers(86%) didn't recognize the injury of the natural environment, the enlightment movement and the public information for the protection of natural environment are urgent. And they thought that the good campsite is located near the stream(43.6%) or a quiet place(33.4%). 3. As the space per a man increase, the degree of their satisfactions showed the tendency to increase. The user's satisfaction were analyzed by three statistic methods, correlation, multiple regression and factor analysis. Affecting factors to the user's psychology by the varimax varimax rotated factor analysis were classified physical arts ecological satisfaction. 4. The carrying capacity of the campsite by the degree of psychological satisfaction of the user was measured. The result was that the proper space for one user campsite was 35m2 5. The 58% of the informants said that they root disturbed by the overcrowding in the campsite. But most of the users thought that it was not good to control the number of the users. And the 67.3% of the respondents answered that the best method was that we control the number of the users by order of arrival if we have to control it.

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The Electrical Properties of Thickness Vibration Mode Multilayer Piezoelectric Transformer using Low Temperature Sintering (Pb,Ca,Sr)Ti(Mn,Sb)O3 Ceramics (저온소결 (Pb,Ca,Sr)Ti(Mn,Sb)O3 세라믹스를 이용한 두께진동모드 적층 압전 변압기의 전기적 특성)

  • Kim, Do-Hyung;Yoo, Ju-Hyun;Jeong, Yeong-Ho
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.06a
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    • pp.306-306
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    • 2007
  • 최근, LED 구동 인버터, DC-DC 컨버터, AC-DC 컨버터 및 형광등 ballaster 등의 고전압전원장치등에 압전변압기를 적용하고자 하는 연구가 활발히 진행되고 있다. 순수한 PbTiO3는 큐리온도(490C)가 높고, 기계적강도가 크며, 비유전율(약 200 정도)이 작다. 또한, 두께방향 진동의 전기기계 결합계수 (Kt)가 윤곽진동의 전기기계 결합계수(Kp)보다 크므로 두께방향의 진동모드를 이용한 벌크파 진동자의 경우 윤곽진동방향으로 불요신호(spurious signal)가 적고, 작은 grain size(1μm정도)로 미세가공이 가능하여 고주파 재료로 이용되고 있다. 압전변압기의 출력 전력을 향상시키기 위해서는 적층으로 제작하여야 하는데 적층 압전변압기 제작시 층간의 내부 전극이 도포된 상태에서 소결하여야 한다. 이때 소걸 온도가 높으면 Pd 함랑이 높은 전극을 사용하여야 하는데 Pd 전극의 가격이 비싸 소자의 경제성이 떨어지게 된다. 따라서 순수한 Ag 전극을 내부전극으로 사용하기 위해서는 900C 이하에서 소결이 가능하여야 한다. 따라서 본 연구에서는 (Pb,Ca,Sr)Ti(Mn,Sb)O3 조성을 이용하여 900C 이하의 저온소결이 가능한 두께방향진동모드 적층 압전변암기를 제작하여 그에 대한 전기적 특성을 조사하였다.

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Biological Activities of Cosmetic Material from Ten Kinds of Flower Ethanol Extracts (화장품 소재로서의 꽃 10 종 에탄올추출물 생리활성 특성연구)

  • Lee, Tae Bum;So, Yang Kang;Kim, Se Yul;Hwang, Ji Young
    • Korean Journal of Medicinal Crop Science
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    • v.28 no.4
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    • pp.260-275
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    • 2020
  • Background: We investigated the antioxidant, anti-wrinkles, whitening, and moisturizing properties and amounts of phenolic compounds of ethanol extracts from flowers of 10 resource plants from Namwon and Mt. Jiri., Korea. Methods and Results: We measured antioxidant efficacy based on the total polyphenol, and total flavonoid content, and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. We evaluated the inhibitory effect on melanin synthesis and tyrosinase activity for the whitening effect. Furthermore, we analyzed the elastase and matrix metalloproteinase-1 (MMP-1) inhibition activity for anti-wrinkle capacity. To evaluate the moisturizing effect, we examined hyaluronan synthase (HAS) mRNA expression. In addition, the 19 phenolic compounds were detected using high performace liquid chromatography (HPLC). Among the 10 flowers, the antioxidant effect was high in the order of Rosa multiflora, Nelumbo nucifera, and Elsholtzia splendens. Whitening effect was high in the order of N. nucifera, R. multiflora, and Dendranthema zawadskii. As for the anti-wrinkle property, N. nucifera was the most effective followed by R. multiflora. Taraxacum coreanum was the best for moisturizing effect, followed by D. zawadskii, and E. splendens. Seven phenolic compounds were detected in the extracts of the 10 flowers. Conclusions: Overall, the extracts of five flowers extracts showed strong potential as antioxidant, whitening, anti-wrinkle, and moisturizing functional cosmetic agents.

Geomorphic Development of Tucson and Chiricahua in Arizona, U.S.A (미국 아리조나 투산과 치리카와 지역의 지형발달)

  • PARK, Heui Doo
    • Journal of The Geomorphological Association of Korea
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    • v.15 no.2
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    • pp.1-9
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    • 2008
  • This studied area is divided into the mountains and the valleys. The former is nearly consisted of the badland, the latter is consisted of alluvial plains in the valley, fluvial terrace at the side of the river, alluvial fans between mountains and river terrace. There are many tors, mushroom rocks, sugarloaves, weathering pits, castle coppies, columnar rocks, pinnacles, balanced rocks carved on tuff by means of erosion in the Chiricahua Nat'l Monument. Willcox Playa is alkalic crust where was lake in pleistocene epoch at the time wetter than present. Alkalic crust was made of Ca, Na, K etc. There are sand dunes around here where was lake side in the past. We found many kinds of fossils at the 2,000ft thick horizons of valley alluvium. Pediment and alluvium bordered at the base of Mt. Dragoon wavily. Exfoliation and spalling and sheeting resulted in boulders around here. Tucson is alluvial plain filled in thick 7,0000ft valley. Volcano, fault, erosion, alluvium were and are processing in this area.

A Study on the Holocene Environments of the Jemin Plain in Gongju, Chungnam Province (충남 공주 제민평야의 홀로세 환경연구)

  • PARK, Ji Hoon;LEE, Ae-Jin
    • Journal of The Geomorphological Association of Korea
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    • v.24 no.2
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    • pp.65-78
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    • 2017
  • In this study, stable carbon isotopic analysis (22 specimens) and magnetic susceptibility analysis (23 specimens) were conducted out on the specimens collected from two points (trench DT1, DT2) in the floodplain of Jemincheon(hereinafter the Jemin plain) to reconstruct the Holocene Environments (Period I, Period II, Period III) of the Jemin plain in Gongju, Chungnam. The results were as follows: In Period I (approximately 7,480~4,940 yrs B.P.) and especially around 7,480~7,320 yrs B.P., it was cool-dry and there were two minor climate fluctuations. This period received a continuous flow of sediments, rather than massive amounts of sediments due to abrupt flooding, and therefore, there was almost no soilization process. Period II(approximately 4,940~2,600 yrs B.P.) was also relatively cool-dry. However, in Period II b, unlike I, the minor climate fluctuations were less pronounced. In this period, flooding and desiccation repeated, inducing soilization processes especially around 3,160 yrs B.P. In Stage III (~360 yrs B.P.), it was warm and humid compared to II b. However, in III a, there was no inflow of sediments due to irregular flooding, and in fact, soilization process was more manifested than during II b due to the impact of the desiccation environment. However, there were some mass movements from Bonghwang Mt. (a.s.l. 147m) caused by heavy rains and typhoon during III b (approximately 360 yrs B.P.), thus moving a large amount of debris (i.e. gravel), which resulted in sedimentation.