• Title/Summary/Keyword: 검은모래

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화학의 세계-해변의 검은 모래ㆍ초록 모래

  • Jin, Jeong-Il
    • The Science & Technology
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    • v.31 no.2 s.345
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    • pp.11-11
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    • 1998
  • 프랑스 남부 해변가엔 하얀 모래, 그리고 하와이 해변가엔 검은 모래와 초록 모래가 지구촌의 피서객을 유혹하고 있다. 이처럼 신비스런 모래들은 어떻게 태어났는가. 하얀 모래는 태고 때부터 이어온 석회질 껍질로 된 해양생물의 유산물이며 검은 모래나 초록 모래는 화산에서 나온 용암이 오랜 세월의 풍화작용을 통해 생성된 것이다.

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국내시장정보

  • Korea Far Infrared Association
    • Journal of Korea Far Infrared Association
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    • s.17
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    • pp.36-43
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    • 2003
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Analysis of the clinker formed in circulating fluidized bed boiler (유동층 보일러에 생성된 크링커에 대한 분석)

  • Kim, Kyeong-Sook;Park, Hyun-Joo;Lee, Tae-Won;Jeong, Nyeon-Ho
    • Analytical Science and Technology
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    • v.13 no.1
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    • pp.5-11
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    • 2000
  • During the commissioning period in Tonghae thermal power plant which is the largest circulating fluidized bed boiler in the nation, a considerable amount of clinker was formed at FBAC and seal pot. Various attempts, for example, concentration analysis, surface phenomena, thermal characterization, and crystal structure of ash, bed sand, limestone, clinker, and mixture of each gradients have been studied to identify the causes of clinker formed in circulating fluidized bed boiler. As the results, the characterization of black particles in which separated from the clinker is more similar to that of bed sand, on the other hand, white particles are more similar to ash. In addition, the sintering temperature of sand is over $1,200^{\circ}C$ and this temperature was decreased as limestone is added to bed material. The cause of clinker was proved that ash was sticked to molten or sintered sand or limestone in the area of high temperature in the circulating system.

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First Record of the Lizardfishes, Synodus fuscus (Synodontidae, Aulopiformes) from Korea (한국산 꽃동멸속 어류 1 미기록종, Synodus fuscus Tanaka)

  • Choi, Youn
    • Korean Journal of Ichthyology
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    • v.24 no.4
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    • pp.311-313
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    • 2012
  • A single specimen of Synodus fuscus belonging to the genus Synodus in family Synodontidae was firstly collected from the coastal waters of Jeju Island, Korea. We newly add this species to the Korean fish fauna and propose its new Korean name, "Mo-rae-kkot-dong-myeol". This species was characterized by having no conspicuous pigmented area on operculum. The dorsal fin base is shorter than 1/2 of the head length. The morphological measurements and counts of Synodus fuscus were described in detail and a key to species of the genus Synodus from Korea provided in this study.

Distribution of Flood Sediment Deposits using the Seafloor Image by Side Scan Sonar near the Northern Coast of Gungchon-ri, East Sea (Side scan sonar 해저면 음향영상을 이용한 동해 궁촌리 북부 연안의 홍수퇴적물 분포)

  • Lee, Cheol-Ku;Jung, Seom-Kyu;Kim, Seong-Ryul
    • Journal of the Korean earth science society
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    • v.34 no.1
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    • pp.41-50
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    • 2013
  • To analyze the distribution pattern of flood sediment deposits near the mouth of Chucheoncheon (river), side scan sonar images and seafloor sediment properties were investigated in the offshore area within about 50 m deep in water. Based on the analysis result of the sonar images, the seafloor of the study area is divided into three areas of basement, sandy-mud, and dispersed flood sediment. The colors of sonar images in each area are represented by dark black, light grey, and greyish black, respectively. The sediment composition in the grey black area shows 33.73% of gravel, 62.88% of sand, 3.37% of silt, and 0.02% of clay. On the other hand, the composition of the light grey area is 10.31% of sand, 56.42% of silt, and 33.27% of clay. Especially the sediment of the grey black area contains the considerable amount of burned plant fragments in black color, which could distinctly be differentiated from those in the offshore. The distribution pattern of the flood sediment deposits suggests that the land-originated detrital sediments seem to be transported from the Chucheon river into offshore along the shore rather than transversely. In conclusion, the longshore current of the study area is probably dominant to affect the spatial distribution of bottom features.

Study on the Biophysical and Ecological Characteristics of the Streams - A Case of the Sand Streams in Kyonggi-Do District- (하천의 물리적 생태적 특성 연구 - 경기지방 모래하천의 사례 -)

  • Kim Hyea-Ju
    • Korean Journal of Environment and Ecology
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    • v.19 no.3
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    • pp.215-230
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    • 2005
  • To analyze physical and ecological characteristics of sand streams, Cheongmi, Yanghwa and Bokha streams on the similar environment were Lnvestigated and estimated. According to the estimation results of physical structures, ecological properties of the Cheogmi and Yanghwa streams were classified as 'fair to good', and the Bokha stream was classified as 'fair'; commonly, the representing streams were comparatively active on meandering and accumulation; on the other hand, erosion was less active. As a result of the study for flora on this 3 streams, $Phaiaris\;arundinacfa\rightarrowPhragmites\;japonica\rightarrowPhragmites\;communis\rightarrowSalix\;koreensis\rightarrowFraxinus\;rhynchophylla\rightarrowRobinia\;pseudo-acacia-Acer$ ginnala communities were developed in order of being closest to the water shore. In case of benthic macroinvertebrates, Ephemera striga ta Eaton and Cajopteryx atrata Selys, usually inhabited in the uncontaminated water, were investigated as common species. Besides, Limnodrilus gotoi Hatai and Family Chironomidae sp. 1 were the common dominant benthic macroinvertebrates.

Soil Deformation Tracking in Model Chamber by Targetless Close-Range Photogrammetry (무타겟 사진측량 기반 모형 토조 내 지반 변위 측정)

  • Lee, Chang No;Oh, Jae Hong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.37 no.6
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    • pp.555-562
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    • 2019
  • This paper presents soil deformation measurement in model chamber based on photogrammetry. We created an aluminum framed acrylic model chamber with soil inside and applied photogrammetry to measure soil deformation caused by loading tests. The soil consists of 40% black and 60% regular sand to create image contrast in soil images. In preprocessing, the self camera calibration was carried out for IOPs (Interior Orientation Parameters), followed by the space resection to estimate EOPs (Exterior Orientation Parameters) using control points located along the aluminum frame. Image matching was applied to measure the soil displacement. We tested different matching window sizes and the effect of image smoothing. Experimental results showed that 65x65 pixels of window size produced better soil deformation map and the image smoothing was useful to suppress the matching outliers. In conclusion, photogrammetry was able to efficiently generated soil deformation map.

First Record of Bothus pantherinus (Bothidae, Pleuronectiformes) from Korea (한국산 둥글넙치과(Bothidae) 어류, Bothus pantherinus의 첫기록)

  • Si-Yeong Jeong;Jin-Koo Kim
    • Korean Journal of Ichthyology
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    • v.35 no.1
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    • pp.44-49
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    • 2023
  • A single specimen of the genus Bothus (family Bothidae) was collected for the first time at the intertidal zone of Moseulpo Port, Daejeong-eup, Seogwipo-si, Jejudo Island, on 14 August 2022. The specimen was identified as Bothus pantherinus in having following morphological traits: dark spots and ring-shaped patterns near eyes and the pectoral fins, one distinct spot in the center of the lateral line, 75 lateral line scales, and seven hourglass shaped supracranial pterygiophores. As a result of analyzing 603 bp of mitochondrial DNA COI sequences, our specimen was perfectly matched to those of B. pantherinus registered in NCBI. It has been known that the species is widely distributed throughout the Indo-Pacific Ocean from Red Sea to Hawaiian (32 degrees north to 32 degrees south), but this study revealed that its distribution expanded to the waters of Jejudo Island (33 degrees north), Korea. We propose its new Korean name "Beot-kkoch-mu-nui-dung-geul-neob-chi".

Promotion Directions of Spa Industry Using Local Resources in Jeju Island, Korea (제주도 향토자원을 활용한 스파산업 육성방향)

  • Yoon, Hye Yung
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.8 no.1
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    • pp.69-78
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    • 2013
  • Settled lifestyle as important to health and healing to medical tourism and wellness tourism in the 21st century has emerged as the best promising service industry. Jeju Island has a variety of local resources, and the directions was considered to spa industry promotion application it. Jeju Island has a variety of local resources which can be used for spa industry promotion. Jeju Island's beautiful natural environment, mineral resources, water resources, biological resources, agricultural products, traditional folk remedies available in Jeju's spa treatments. Using the local resources of Jeju, 'Jeju specialized spa treatments' can develop of 12 kinds of spa treatments. Namely, thalssotherapy, stone therapy, black sand poultice, hot-floored therapy using volcanic soil, thalassotherapy, drinking therapy, hydrotherapy, herbal/medicinal plants poultice, forest therapy, Spa cuisine, facial beauty, diet therapy. 12 kinds of Jeju specialized spa treatments development and service to the local resources of basic research on the physical and chemical characteristics, product development, clinical trials, efficacy studies should precede. In addition, customized spa services programs should be developed considering the propensity of customers, customer needs, and a spa type. And standardized program of spa services and need a manual painter. Medical tourism and wellness tourism in conjunction with efforts to be considered in order to increase the competitiveness of the spa industry in Jeju.

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Experimental and Numerical Study on the Effect of the Rain Infiltration with the Increase of Surface Temperature (지표면 온도상승이 빗물의 토양침투에 미치는 영향에 대한 실험 및 수치 해석적 연구)

  • Shin, Nara;Shin, Mi Soo;Jang, Dong Soon
    • Journal of Korean Society of Environmental Engineers
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    • v.35 no.6
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    • pp.422-429
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    • 2013
  • It is generally known that the increase of the Earth surface temperature due to the global warming together with the land desertification by rapid urban development has caused severe climate and weather change. In desert or desertification land, it is observed that there are always severe flooding phenomena, even if desert sand has the high porosity, which could be believed as the favorable condition of rain water infiltration into ground water. The high runoff feature causes possibly another heavy rain by quick evaporation with the depletion of underground water due to the lack of infiltration. The basic physics of desert flooding is reasonably assumed due to the thermal buoyancy of the higher temperature of the soil temperature than that of the rain drop. Considering the importance of this topic associated with water resource management and climate disaster prevention, no systematic investigation has, however, been reported in literature. In this study, therefore, a laboratory scale experiment together with the effort of numerical calculation have been performed to evaluate quantitatively the basic hypothesis of run-off mechanism caused by the increase of soil temperature. To this end, first, of all, a series of experiment has been made repeatedly with the change of soil temperature with well-sorted coarse sand having porosity of 35% and particle diameter, 2.0 mm. In specific, in case 1, the ground surface temperature was kept at $15^{\circ}C$, while in case 2 that was high enough at $70^{\circ}C$. The temperature of $70^{\circ}C$ was tested as this try since the informal measured surface temperature of black sand in California's Coachella Valley up to at 191 deg. $^{\circ}F$ ($88^{\circ}C$). Based on the experimental study, it is observed that the amount of runoff at $70^{\circ}C$ was higher more than 5% compared to that at $15^{\circ}C$. Further, the relative amount of infiltration by the decrease of the surface temperature from 70 to $15^{\circ}C$ is about more than 30%. The result of numerical calculation performed was well agreed with the experimental data, that is, the increase of runoff in calculation as 4.6%. Doing this successfully, a basic but important research could be made in the near future for the more complex and advanced topic for this topic.