• Title/Summary/Keyword: 곡면 비교

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Assessment of Productivity and Vulnerability of Climate Impacts of Forage Corn (Kwangpyeongok) Due to Climate Change in Central Korea (국내 중부지역에 있어서 기후변화에 따른 사료용 옥수수의 생산성 및 기후영향취약성 평가)

  • Chung, Sang Uk;Sung, Si Heung;Zhang, Qi-Man;Jung, Jeong Sung;Oh, Mirae;Yun, Yeong Sik;Seong, Hye Jin;Moon, Sang Ho
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.39 no.2
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    • pp.105-113
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    • 2019
  • A two-year study was conducted from 2017 to 2018 by the establishment of a test field at Chungju-si and Cheongyang-gun. Plant height, number of leaves, insects and diseases, and fresh and dry matter yields for corn hybrid('Kwangpyeongok') were investigated. Daily average, maximum, and minimum temperature, monthly average temperature, daily precipitation, and sunshine duration during the growing season were investigated. We selected climate-critical factors to corn productivity and conducted an evaluation of vulnerability to climate change from 1999 to 2018 for both regions. In 2018, the dry matter yield of forage corn was 6,475 and 7,511 kg/ha in Chungju and Cheongyang, respectively, which was half of that in 2017. The high temperature and drought phenomenon in the 2018 summer caused the corn yield to be low. As well as temperature, precipitation is an important climatic factor in corn production. As a result of climate impact vulnerability assessment, the vulnerability has increased recently compared to the past. It is anticipated that if the high temperature phenomenon and drought caused by climate change continues, a damage in corn production will occur.

A Study on the Locations of Jagiso and Dogiso in Najumok Recorded in the 'Sejongsylrok Jiliji' (『세종실록(世宗實錄)』 「지리지(地理志)」 나주목(羅州牧)의 자기소(磁器所)·도기소(陶器所) 위치 연구)

  • Sung, Yun-gil
    • Korean Journal of Heritage: History & Science
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    • v.52 no.3
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    • pp.4-37
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    • 2019
  • Buncheong Ware, which was produced for approximately 200 years from the end of the Goryeo Dynasty to the beginning of the Joseon Dynasty, was used for royal house and state affairs during the early Joseon Dynasty. Records of Buncheong Ware can be found with Jagiso and Dogiso, considered the place of production, in the 'Sejongsylrok jiliji'. This is notable, unlike celadon and white porcelain. However, compared to Gyeongsangnam-do and Gyeongsangbuk-do, the study of Jagiso and Dogiso in Jeollanam-do and Jeollabuk-do has been unsatisfactory. In this paper, we examined the locations of Jagiso and Dogiso in the Jeollanam-do prefecture. This study is focused on Najumok, located in the western part of Jeollanam-do. The following research results were obtained: First, the locations of Jagiso and Dogiso in nine areas were examined. These nine areas comprised Najumok and its immediate provinces of Haejingun, Yeongamgun, Yeonggwanggun, Hampyeonghyeon, Muanhyeon, Gochanghyeon, Heungdeokhyeon and Jangseonghyeon. Previous research results exist for some of the regions; however, only Buncheong Ware was used to estimate Jagiso and Dogiso. In this paper, we tried to discover a more accurate position of Jagiso and Dogiso through a comparison of the place names recorded in the 'Sejongsylrok jiliji' and the place names recorded in the 'Hoguchoungsu'. Also, pottery-related area names and Buncheong Ware obtained from the field survey were reviewed. Table 2 shows the specific positions of Jagiso and Dogiso in the areas examined. Second, it would appear that pottery was produced not only in Jagiso but also in Dogiso. This is because much of Buncheong Ware was unearthed in Najumok, Yeongamgun, and Muanhyeon Dogiso. However, it was only excavated from the Buncheong Kiln Site in Yucheon Village, Sangweol-ri, Yeongam-gun; there could be limitations regarding to the rest of the areas because only a field survey was conducted, not an excavation. A recent excavation at Donggok Village in Cheongdo-ri, Gimje also confirmed a Buncheong Kiln Site. There were two Buncheong Ware ('公', '上') artifacts excavated from the site, believed to be Gongnapjagi. In addition, Cheongdo-ri, where the Buncheong Kiln Site is located, was found to be an area in Wurimgokmyeon, a former Wurimgok at a Dogiso in Jeonjubu. Consequently, it would seem that Dogiso also produced porcelain (Buncheong Ware). If more data can be obtained from the excavations at sites considered to be Dogiso, the results of Dogiso-related research will be strengthened. Third, in previous surveys, field surveys and excavation surveys were based on estimates using artifacts, but the name of the location of the Jagiso and Dogiso may be confirmed more accurately by tracking the changes in the names of the administrative areas. Therefore, although it is important to conduct research using the results of surveys or excavations, changes in the place names or places related to porcelain must not be overlooked.

A Study on the Quality Control of Transvaginal Ultrasound Transducer using ATS-539 Ultrasound Phantom (ATS-539 초음파 팬텀을 이용한 경질 초음파 검사용 탐촉자의 정도관리에 대한 연구)

  • Park, Ji Hye;Heo, Yeong Cheol;Kim, Yon min;Han, Dong Kyoon
    • Journal of the Korean Society of Radiology
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    • v.15 no.4
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    • pp.463-472
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    • 2021
  • Demand for examinations using transvaginal transducer with high frequencies is increasing to observe pelvic organs in gynecological ultrasound tests. However, the quality control of the replacement probe in clinical trials is not properly implemented and the evaluation criteria have not been established. Therefore, 58 transvaginal transducers and 20 convex transducers were applied to the ATS-539 ultrasound phantom for 20 ultrasound devices currently in clinical use to obtain their respective images and measure them quantitatively and qualitatively. For quantitative measurements, vertical measurement, horizontal measurement, and focal zone and qualitative measurements, dead zone, axial·lateral resolution, sensitivity, functional resolution, gray scale·dynamic range were performed. Quantitative statistical analysis showed significant differences between the two transducers in the lateral measurement and local area (p<0.05). qualitative comparative analysis showed differences in sensitivity and functional resolution. This occurs due to the difference in frequency between transducers and the transducer's injection geometry. Based on the above experiments, the tolerance for horizontal measurement is raised to 10% (±8 mm), the tolerance for sensitivity is observed up to 6 cm deep, which is 12 cm deep,which is the level of the third quartile (75%). The permissible range of functional resolution is up to 6 (12 cm), 6 (12 cm), 11 (11 cm), 9 (9 cm), 6 (6 cm) target, which is the level of the third quartile (75%). It is considered reasonable to adjust the depth of targets in gray scale·dynamic range to measure at a depth of 2 cm, which is 50% of the depth of 4 cm. As above, the criteria for evaluating the quality of transvaginal transducer for use in the past have been proposed and it is expected that this study will be used as a basic data for the production of phantom exclusively for transvaginal transducer in the future.