• Title/Summary/Keyword: red data

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Prediction of Red Tide Occurrence by using Oceanic and Atmospheric Data by Satellite (인공위성을 통한 해양·기상자료를 이용한 적조발생예보)

  • Oh, Seung-Yeol;Park, Jae-Moon;Yoon, Hong-Joo
    • The Journal of the Korea institute of electronic communication sciences
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    • v.10 no.2
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    • pp.311-318
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    • 2015
  • Red tide occurs every year in the coastal seas of the South Korea, This phenomena has become a national issue of environmental and economic damage. In this study, we analyzed a suitable conditions to occur the red tide by using oceanic and atmospheric data during 10 years, These factors were applied to predict the red tide occurrence from 2012 to 2014. As a result, in 2012 and 2013, it is able to alarm the red tide occurrence before 6~11 days. However, in compared to the normal year and 2014, the prediction of red tide occurrence were less accurate because of more precipitation, short sunshine duration, low temperature waters. Therefore, it is necessary to further investigate the impact of sunshine duration(Solar radiation) on red tide occurrence, it is more necessary to consider the comprehensive analysis using additional oceanic and atmospheric factors.

Analysis of Red Tide Movement in the South Sea of Gyeongnam Province Using the GOCI Images of COMS (천리안 위성영상을 이용한 경상남도 남해안해역 적조이동 패턴 분석)

  • Kim, Dong Kyoo;Kim, Mi Song;Yoo, Hwan Hee
    • Journal of Korean Society for Geospatial Information Science
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    • v.23 no.1
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    • pp.65-71
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    • 2015
  • Red Tide phenomenon which happens in the southern coast of Korea gives massive damage to the fishermen who run fish farms and thereby a lot of efforts to prevent damage are made from various angles. In particular, red tide monitoring with satellite imagery can make it possible to obtain the occurrence data of red tide throughout the whole areas of the sea, which helps provide important information for establishing the preventive plans of disasters. In this regard, this study selected the South Sea of Gyeongnam Province with a view to suggesting the monitoring results with regard to the spread and reduction of the Red Tide in the middle of the day by using the GOCI Images of COMS. With this intention, it selected the region in the South Sea of Gyeongnam Province. The study results of analysis on the GOCI image data for the years of 2013(Aug. 12) and 2014 (Sep. 11) are as follows: the pattern of the Red Tide in the region of the South Sea occurred in the southern sea area of Geoje-do in the morning. It gradually spread and showed a gradual decline after reaching the top at 1 PM. In addition, in terms of the tide movement in the middle of the day, Red Tide began in the southern sea area and moved to the west, and moved to the east again at noon. It is judged that additional study on many factors such as the characteristics of the future Red-tide organisms, tidal currents, amount of sunshine, and water temperature is needed, but it is estimated that Red Tide movement monitoring with GOCI images would provide very crucial information for predicting the spread and movement of the Red Tide to protect and manage the Red Tide disasters.

Detection of Red Tide Patches using AVHRR and Landsat TM data (AVHRR과 Landsat TM 자료를 이용한 적조 패취 관측)

  • Jeong, Jong-Chul
    • Journal of Environmental Impact Assessment
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    • v.10 no.1
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    • pp.1-8
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    • 2001
  • Detection of red tides by satellite remote sensing can be done either by detecting enhanced level of chlorophyll pigment or by detecting changes in the spectral composition of pixels. Using chlorophyll concentration, however, is not effective currently due to the facts: 1) Chlorophyll-a is a universal pigment of phytoplankton, and 2) no accurate algorithm for chlorophyll in case 2 water is available yet. Here, red band algorithm, classification and PCA (Principal Component Analysis) techniques were applied for detecting patches of Cochlodinium polykrikoides red tides which occurred in Korean waters in 1995. This dinoflagellate species appears dark red due to the characteristic pigments absorbing lights in the blue and green wavelength most effectively. In the satellite image, the brightness of red tide pixels in all the three visible bands were low making the detection difficult. Red band algorithm is not good for detecting the red tide because of reflectance of suspended sediments. For supervised classification, selecting training area was difficult, while unsupervised classification was not effective in delineating the patches from surrounding pixels. On the other hand, PCA gave a good qualitative discrimination on the distribution compared with actual observation.

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Analysis of Red Pepper Calyx Cutting Using a Rotational Cutter (회전날을 이용한 홍고추의 꼭지 절단 경향 분석)

  • 이승규;송대빈;정의권
    • Journal of Biosystems Engineering
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    • v.28 no.3
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    • pp.209-216
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    • 2003
  • Red pepper calyx cutting devices using a impacting force by a rotational cutter were devised and tested to obtain the fundamental data for development of a calyx removal unit. Fresh red peppers with 80∼87%(w.b.) of initial moisture contents were used as experimental materials. Square and wire type of rotational cutters were used to cut the red pepper calyx and the fresh red peppers were fed into the device both manually and automatically. Three rotational speeds of 250, 500, 700rpm were selected for a square, and 1000, 1500, 1800rpm for a wire type cutter respectively. Four types of red pepper fixing unit were used in manual feeding. The cutting rate of the square type cutter was over 50% regardless the shape and specification of the cutter. For the wire type cutter, the copper wire and nylon chord could not be applied to cut the red pepper calyx because of the low cutting rate. But for the fine wire, the cutting rate was higher and the cutting mechanism was more steady than copper wire and nylon chord. The cutting rate of automatic feeding and wire type cutting unit was about 70% for all levels of the rotational speed. The cutting rate was highly related to the impacting point of red pepper in carrier box. To increase the cutting rate using the rotational cutter, a proper device and mechanism was required to keep the impacting point consistently.

Fluoride Removal from Aqueous Solutions using Industrial Waste Red Mud (산업폐기물인 적니를 이용한 불소 제거)

  • Um, Byung-Hwan;Jo, Sung-Wook;Kang, Ku;Park, Seong-Jik
    • Journal of The Korean Society of Agricultural Engineers
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    • v.55 no.3
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    • pp.35-40
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    • 2013
  • The present study was conducted to investigate the adsorption potential of red mud for fluoride removal. Different operation parameters such as the effect of contact time, initial concentration, pH, competing anions, seawater, adsorbent dose amount, and adsorbent mixture were studied. Nearly 3 hr was required to reach sorption equilibrium. Equilibrium sorption data were described well by Langmuir model and the maximum adsorption capacity of red mud was 5.28 mg/g. The fluoride adsorption at pH 3 was higher than in the pH range 5-9. The presence of anions such as sulfate, nitrate, phosphate, and bicarbonate had no significant effect on fluoride adsorption onto red mud. The fluoride removal by red mud was greater in seawater than deionized water, resulting from the presence of calcium and magnesium ion in seawater. The use of red mud alone was more effective for the removal of fluoride than mixing red mud with other industrial waste such as oyster shells, lime stone, and steel slag. This study showed that red mud has a potential application in the remediation of fluoride contaminated soil and groundwater.

A Study on the Color of Natural Solvent for the Red Color Reproduction of Safflower

  • Lee, Mi Young;Wi, Koang Chul
    • Journal of Conservation Science
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    • v.37 no.1
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    • pp.13-24
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    • 2021
  • Safflower, a natural dye representing red, is the dye that materials and dyeing method are recorded in the literature, including materials and dyeing. Although the safflower is the same, the ash used as a mordant is recorded differently in each literature, which greatly affects the aesthetic perspective in realizing the traditional safflower red. Therefore, the optimal conditions for realizing the traditional safflower red were sought. The experiment was conducted by pH investigation, dyeing and color analysis by dyeing solution water, concentration, and temperature by ash, and the unique color of red was confirmed. As a result of the test, the pH point of time when the uniq ue color was expressed was 11.53 as goosefoot ash (natural bedrock water), which was 1:100 for concentration and 70℃ for temperature, which was easier to extract red pigment than other ash, indicating that it is suitable for safflower dyeing. The analysis of the ash showed that K and Si play an important role in dyeing, especially Si, which is an element that inhibits carthamon. The color of red was similar to that of KS Standard vivid purplish red in the ash of the goosefoot, and the other ash was deep purplish pink. In the light of findings, it was possible to quantify the dyeing method through traditional materials and find the standard color of red color, and it is judged to be a basic data for studying the unique color of natural materials.

Detection of Red Tides by IRS/OCM Imagery

  • Kang, Y.Q.;Suh, Y.S.
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.697-699
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    • 2003
  • We present a simple algorithm for detection of red patches by remote sensing in coastal waters of Korea. The red tide patches can by identified by the relative intensity of red band signal with respect to the blue-green background signal, provided the radiometric signals only in the sea area are properly stretched. We tested our algorithm by Ocean COlor Monitor(OCM) data of Indian Satellite IRS-P4, which has been received from 2001 by National Fisheries Research and Development Institute of Korea. A comparison of our results with observation shows that the locations of red tides derived from remote sending imagery by our algorithm are in accordance with observations.

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A Study of Band Characteristic of Color Aerial Photos for Image Matching (영상 정합을 위한 컬러 항공사진의 밴드 특성에 관한 연구)

  • Kim, Jin-Kwang;Lee, Ho-Nam;Hwang, Chul-Sue
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2007.04a
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    • pp.187-190
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    • 2007
  • This study is for analyzing best band in image matching using correlation coefficient of left and right images of stereo image pair, lot red, green, blue band images separated from color aerial photo and gray image converted from the same color aerial photo image. The image matching is applied to construct Digital Elevation Model(DEM) or terrain data. The correlation coefficients and variation by change of pixel patch size are computed from pixel patches of which sizes are $11{\times}11{\sim}101{\times}101$. Consequently, the correlation coefficient in red band image is highest. The lowest is in blue band. Therefore, to construct terrain data using image matching, the red band image is preferable. As the size of pixel patch is growing, the correlation coefficient is increasing. But increasing rate declines from $51{\times}51$ image patch size and above. It is proved that the smaller pixel patch size than $51{\times}51$ is applied to construct terrain data using image matching.

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A Hierarchical Binary-search Tree for the High-Capacity and Asymmetric Performance of NVM (비대칭적 성능의 고용량 비휘발성 메모리를 위한 계층적 구조의 이진 탐색 트리)

  • Jeong, Minseong;Lee, Mijeong;Lee, Eunji
    • IEMEK Journal of Embedded Systems and Applications
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    • v.14 no.2
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    • pp.79-86
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    • 2019
  • For decades, in-memory data structures have been designed for DRAM-based main memory that provides symmetric read/write performances and has no limited write endurance. However, such data structures provide sub-optimal performance for NVM as it has different characteristics to DRAM. With this motivation, we rethink a conventional red-black tree in terms of its efficacy under NVM settings. The original red-black tree constantly rebalances sub-trees so as to export fast access time over dataset, but it inevitably increases the write traffic, adversely affecting the performance for NVM with a long write latency and limited endurance. To resolve this problem, we present a variant of the red-black tree called a hierarchical balanced binary search tree. The proposed structure maintains multiple keys in a single node so as to amortize the rebalancing cost. The performance study reveals that the proposed hierarchical binary search tree effectively reduces the write traffic by effectively reaping the high capacity of NVM.

A Survey of Globular Cluster Systems of Massive Compact Elliptical Galaxies in the Local Universe

  • Kang, Jisu;Lee, Myung Gyoon
    • The Bulletin of The Korean Astronomical Society
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    • v.45 no.1
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    • pp.32.2-32.2
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    • 2020
  • Massive Compact Elliptical Galaxies (MCEGs) found in the local universe are as massive as normal galaxies but extremely compact (M∗ > 1011 Msun, Reff < 1.5 kpc). They are considered to be the relics of red nugget galaxies found at high redshift. They are not likely to have undergone many mergers, keeping their original mass and size. Moreover, it is expected that they host a dominant population of red (metal-rich) globular clusters rather than blue (metal-poor) ones. Indeed, Beasley et al. (2018) found that the color distribution of the cluster system of NGC 1277 is unimodal, showing only a red population. However, NGC 1277 is the only case whose cluster system was studied among MCEGs. In this study, we investigate globular cluster systems of 14 nearby MCEGs with a homogeneous data set of HST/WFC3 F814W/F160W archive images. We detect tens to hundreds of globular clusters in each galaxy and examine their color distributions. Surprisingly, the fractions of red globular clusters are similar to those of normal galaxies, and are much lower than that of NGC 1277. We additionally obtain Gemini/GMOS-N g'r'i' images of PGC 70520, one of the 14 nearby MCEGs, to detect more globular clusters from deeper and wider images. We will discuss the results from the Gemini data combined with the results from the HST data in relation with the formation of MCEGs.

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