• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2022.06a
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• pp.253-256
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• 2022

실사 영상 기반의 메타버스 환경을 구축하기 위한 다수의 카메라를 통한 영상 취득 및 부호화, 전송 기술이 활발히 연구되고 있고, 이를 위해 영상 압축 표준화 단체인 moving picture experts group (MPEG) 에서는 MPEG immersive video (MIV) 표준을 개발하였다. 하지만, 현재 널리 사용되는 가상 현실 영상을 스트리밍 가능한 장비의 연산 능력으로는 MIV 기반 몰입형 영상을 스트리밍 시 복호기 동기화 문제가 발생할 수 있다. 따라서 본 논문은 저사양 및 고사양 장비에서 적응적으로 복호기 개수를 조절 가능한 geometry packing 기법을 MIV 의 참조 소프트웨어인 test model for immersive video (TMIV)에서 구현한다. 제안하는 패킹 기법은 지오메트리 영상을 패킹하여 텍스쳐 영상과 같은 높이를 가지도록 한 후 각각 단일 서브픽쳐 (subpicture) 로 부호화한다. 이후 부호화된 서브픽쳐들에 적응적으로 비트스트림 병합이 적용되어 장비의 복호기 사양에 대응한다.

• Journal of Sericultural and Entomological Science
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• v.14 no.1
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• pp.1-7
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• 1972

Recently, young mulberry trees grown in the reclaimed hill land are frequently attacted by the die-bark and the buds of the trees developed poorly. In order to learn the cause of the injury mentioned above available boron content in the soils and the bark of young shoots have been analyzed. The results are as follow; Available boron content in the soil of the damaged mulberry fold was 0.3-0.20 ppm, against 0.39-49 ppm in that of healthy mulberry field, and boron in the bark of the damaged trees was 10.63-12.99 ppm, and 18.42-21.02 ppm in that of the healthy trees. The organic matter content and available boron content in soils showed a highly significant possitive correlation. The moisture content in percent in the soil of the damaged mulberry held was 11.16 and 14.22 in that of healthy mulberry field.

• Research in Plant Disease
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• v.6 no.1
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• pp.23-26
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• 2000

Effects of infection time of the clubroot pathogen, Plasmodiophora brassicae, on yield loss of Spring-sown Chinese cabbage plants were examined in field experiments. Yield loss of Chinese cabbage plants increased as the infection time becomes early. Plants infected at 20 days after transplanting or earlier were completely killed before harvest, and those infected at 30 days after transplanting were healthy in appearance but their head weights were reduced to 59% with poor commodity value. The plants infected 40 days after transplanting were not affected in yield. Development of root hairs in diseased plants was greatly reduced as the infection progressed, and root length was reduced to 1/2 to 1/3 of that of healthy plants. root galls were first developed 20 days after inoculation and rapidly enlarged to reach the peak in size 20 days from initial development, and decayed thereafter. Development and decay of root galls tended to be faster at later season as air temperature became high, regardless of the infection time. Diseased plants started to wilt approximately 10 days after root gall development. Root galls began to decay 10 days after initial plant wilting, and then were completely rotten within following 10 days. Based on the results, root gall development stages on spring-sown Chinese cabbage plants could be grouped into 20 days of root gall enlargement period, and 10 days of root gall decay period, followed by survival period in soil.

• The Korean Journal of Ecology
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• v.26 no.4
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• pp.181-188
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• 2003

Frequencies of each size class, annual change of tuber state and above ground/belowground rate in sect. Pes-gallinaceua group of Corydalis (Fumariaceae) were studied to clarify spring ephemeral´s growth characteristics from 1999 to 2000 in Namhansansung area. Shoot grew from the tuber corresponding with soil thawing in the early growth season, and the deeper tuber was located in soil, the later shoot germinated. Shoot appeared in middle March and died early in May, and the period of total growth season was 45 days. Frequencies were 40% (in total dry weight) or 53% (in tuber´ dry weight) in the smallest size class, and 93% (in total dry weight) or 96% (in tuber´ dry weight) below medium size, therefore, almost all of plants were small. Specific gravity of tuber (SGT) gradually decreased from late growth season to the time that leaf unfolded in next year. At this time, the value of SGT was 0.14. Thereafter, SGT increased to 0.42 at withering time of aboveground part. During growth season, the SGT of flowering plants was lower than that of non-flowering plants. And SGT difference between flowering plants and non-flowering plants was significant at 1% level. In the late growth season, SGT decreased along the increase of tuber volume. The tuber volume roughly increased along the leaf area but there was no a conspicuous trend. Shoot/tuber rate had nothing to do with tuber volume. SGT decreased and leaf area increased along the tuber dry weight, and tendencies of increase or decrease were conspicuous. Therefore, the smaller the plants were, the larger organic matter accumulated in tuber during a growth season. Shoot/tuber rates were various along each plant.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.1
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• pp.76-80
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• 1983

In order to investigate the effect of boron and phosphorus for reduction of cold injury of rice, this experiment was undertaken by pot trial. Two levels of phosphorus and 6 levels of boron were applied once at the three stages such as tillering, panicle formation and meiosis stage. Cold water was irrigated to maintain cool temperature ranging 15 to $18^{\circ}C$ from panicle formation stage. It was shown a tendency that three to seven days of early heading were resulted by the 3, 5 and 10kg of boron application per 10 are. The ripening ratio and physiological root activity was rather slightly increased in the above boron levels.

• KOREAN POULTRY JOURNAL
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• v.36 no.7 s.417
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• pp.112-115
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• 2004

최근 국내 양계산업을 둘러싸고 있는 여러 여건들을 볼 때 가슴조이는 긴장의 연속이라고 말할 수 있다. 작년 12월 전 세계를 놀라게 한 조류독감(AI)은 우리 닭고기 시장을 얼어붙게 하였으며, 또한 국제 옥수수 수송비 상승과 함께 국내 사료 가격은 불과 6개월 사이에 3차례에 걸쳐 $30\%$ 가까이 올랐고 국제유가도 가파른 상승세를 지속하고 있다. 이러한 고유가, 고사료가 시대를 맞은 우리 양계산업의 경쟁력은 상대적으로 약화됨과 동시에 닭고기 수입량의 증가와 계란 소비의 둔화, 그리고 불안정한 가격체계 등 여러 어려운 문제점들이 현안으로 떠오르고 있다. 이와같이 국제화 시대에 가격 경쟁력을 약화시키는 주요인으로는 병아리 품질 저하와 낙후된 계사시설을 들 수 있으며, 이중 병아리의 품질저하는 우리나라 종계장과 부화장이 영세한데다 병아리의 수급 물량이 쉽게 급변하는데 기인하고 있으며 계사 시설의 낙후는 아직도 생산농가의 사육규모가 영세한데 따른 것으로 볼 수 있다.

• Korean Journal Plant Pathology
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• v.12 no.4
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• pp.459-462
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• 1996

예년과는 달리 6월 중순부터 7월 중순까지 낮은 기온과 잦은 강우로 인한 음습한 날씨가 지속되었던 전남지방의 온실멜론에서 노균병이 격발하였다. 올해 전남지역에서 심하게 발생한 노균병의 병징은 다각형의 모무늬 외에도 불규칙한 대형의 부정형 무늬를 형성하였으며, 이러한 급성형 병징들은 주로 개화기 무렵 아랫잎에서부터 나타나기 시작하여 병이 진전됨에 따라 윗쪽으로 진전되었고 병반이 뭉쳐져 잎을 급속하게 고사시켰다. 표본 조사한 12개 농가의 시설 하우스에서 재배되고 있는 온실멜론의 노균병 이병엽율은 1%에서 100%까지 다양하였으며 수확을 전혀 못한 농가도 있었다. 각 농가에서는 노균병의 방제를 위하여 발병초기부터 농가당 최소 3회에서 최고 8회까지 살균제를 살포하는 방제 노력을 기울였으나 정확한 노균병 진단의 실패와 적정 약제 선정의 실패로 혼선을 빚어 방제효과는 높지 않았으며, 농약의 남용과 오용이 병방제에서 심각한 문제점으로 드러났다.

• Proceedings of the Korean Information Science Society Conference
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• 2006.10a
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• pp.103-107
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• 2006

최근 정보화 시대에 발맞추어 나가기 위해서는 학습자의 문제해결력을 함양하기 위한 능력을 기를 수 있는 교육이 이루어져야 한다. 학습과정에서 학습자 스스로 지식을 조작하고 문제를 해결할 수 있는 학습자중심의 자기 주도적(self-directed) 학습이 강조되고 있다. 이러한 학습을 위하여 웹 기반에서의 문제은행 시스템을 이용하여 자기 주도적 학습과 수준별 학습 평가가 가능하도록 시스템을 설계 및 구현하였다. 본 연구에서 제안하는 시스템은 학습자가 스스로 필요한 문제를 출제하여 학습할 수 있으며, 문제출제 형식은 문제은행방식을 이용한 동적 출제방식을 사용하였다. 학습자가 학습 결과를 즉각적으로 확인하여 직접 피드백 할 수 있으며, 다시 풀어보기를 원하는 문제는 오답노트 기능을 통하여 복습할 수 있도록 하였다. 또한 모의고사를 통한 결과분석에 따라 개인별 심화 및 보충학습을 통해 완전학습 목표에 도달할 수 있도록 하였다. 평가 시 한 과목의 편중을 막기 위하여 비율을 설정해놓았으며, 학습통계에서 평균과 자신의 성적을 비교함으로써 철저하게 자신의 위치를 파악할 수 있도록 하였다.

• Journal of Broadcast Engineering
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• v.27 no.6
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• pp.861-871
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• 2022

The moving picture experts group (MPEG) developed the MPEG immersive video (MIV) standard for efficient compression of multiple immersive videos representing natural contents and computer graphics. The MIV compresses multiple immersive videos and generates multiple output videos which are defined as atlases. However, there is a synchronization issue of multiple decoders in a legacy device when decoding multiple encoded atlases. This paper proposes and implements the geometry packing method for adaptive control of decoder instances for low-end and high-end devices. The proposed method on the recent version of the MIV reference software worked correctly.

• Clinical and Experimental Pediatrics
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• v.51 no.2
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• pp.170-180
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• 2008

Purpose : Some antibiotics were known to exert neuroprotective effects in the animal model of hypoxic-ischemic (H-I) brain injury, but the mechanism is still unclear. A recent study reported that geneticin (G418), an aminoglycoside antibiotic, increased survival of human breast cancer cells by suppressing apoptosis. We investigated the neuroprotective effects of systemically administrated geneticin via anti-apoptosis following the H-I brain injury Methods : Seven-day-old Sprague-Dawley rat pups were subjected to unilateral (left) common carotid artery occlusion followed by 2.5 hours of hypoxic exposure and the cortical cell culture of rat brain was done under a hypoxic incubator. Apoptosis was measured in the injured hemispheres 7 days after H-I insult and in the injured cells from hypoxic chamber using morphologic analysis by Terminal dUTP Nick-end Labeling(TUNEL) assay and immunohistochemistry for caspase-3, and cytologic analysis by western blot and real time PCR for bax, bcl-2, and caspase-3. Results : The gross appearance and hematoxylin and eosin stain revealed increased brain volume in the geneticin-treated animal model of perinatal H-I brain injury. The TUNEL assay revealed decreased apoptotic cells after administration of geneticin in the cell culture model of anoxia. Immunohistochemistry showed decreased caspase-3 expression in geneticin-treated cortical cell culture. Western blot and real-time PCR showed decreased caspase-3 expression and decreased ratio of Bax/Bcl-2 expression in geneticin-treated animal model. Conclusion : Geneticin appears to exert a neuroprotective effect against perinatal H-I brain injury at least via anti-apoptosis. However, more experiments are needed in order to demonstrate the usefulness of geneticin as a preventive and rescue treatment for H-I brain injuries of neonatal brain.