• Title/Summary/Keyword: 수적

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Predictions of Heat and Mass Transfer Rates to a Spray Droplet Experiencing Condensation (응축을 수반하는 분무수적으로의 열 및 질량전달률 예측)

  • 이상균;조종철;신원기;조진호;서정일
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.15 no.5
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    • pp.1763-1773
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    • 1991
  • 본 연구에서는 포화수증기와 공기의 혼합기내에서 분무수적으로의 열 및 질량 전달률을 계산하기 위하여 수적의 부분혼합모형과 비혼합모형에 대하여 수적내 과도온 도분포의 해석해를 적용성이 보장되면서도 계산상의 어려움이 수반되지 않는 형태로 구하기 위하여 수적내부의 열전도해석에 있어서 적분법을 적용하였다. 적분법으로 얻어지는 과도온도분포의 해는 유한차의 다항식으로 표시되어 비혼합모형인 경우 각시 간 구간의 경계에서의 온도분포가 연속성을 유지하면서 물성치들의 온도에 대한 종속 성이 쉽게 고려되고 계산도 용이한 형태이다. 본 보에서 제시하는 해석결과의 적용 성을 조사하기 위하여 완전혼합모형을 포함하는 세가지 수적모형들에 대한 계산결과들 로부터 얻어진 시간변화에 따른 수적의 무차원 체적평균온도변동을 유효한 실험결과들 과 비교, 검토하였으며, 부분혼합모형에 대하여 혼합기의 압력, 수적의 초기온도, 혼 합기 속에 포함되어 있는 수증기의 체적분율, 수적의 초기크기, 수적의 초기속도 및 분사각도가 주위혼합기로부터 수적으로 전달되는 열 및 질량전달에 미치는 영향을 조] 사하고 도출된 대표적인 검토 결과를 제시하였다.

21세기를 대비한 우리의 지상무기체계-자주포

  • An, Chung-Ho
    • Defense and Technology
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    • no.9 s.235
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    • pp.74-85
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    • 1998
  • 야포분야는 수적으로 북한군이 아측에 비하여 2.3배의 우위를 점하고 있다. 수적인 열세를 만회하기 위하여 화력의 발사속도를 증대시켜 포 1문의 능력을 극대화해야 한다. 현재의 자주포에 사거리 연장, 발사속도 증대, 반응성을 향상시킨다면 자주포 1문이 같은 운용 병력으로 대략 2문의 효율을 갖게 될 것이다.

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Two Visualization Techniques Using Smoke-wire and Micro Water-droplets and Their Applications to Vortex Flows (연기선과 미세 수적을 이용한 두 가지 가시화 기법과 와류에의 적용)

  • Sohn, Myong Hwan
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.44 no.12
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    • pp.1017-1026
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    • 2016
  • The present paper describes the two off-surface visualization techniques and their application examples to vortex flows. One of the two visualization techniques is the classical smoke-wire technique, and the other is the visualization technique using the micro water-droplets generated by the home-style ultrasonic humidifier. The smoke-wire technique has the limit of air flow speed (about 5 m/sec for 0.07 mm-diameter wire) and the pollution problem, but it produces very fine and clear streak line sheet. It is applied to visualize the wing-tip vortices of a 3-dimensional wing. The micro water-droplet technique has the larger limit of air flow speed (above 10 m/sec) and is free from pollution and toxic problems compared to the smoke-wire technique. It is successfully applied to visualize the complex vortex system of a double-delta wing with an apex strake.

Effects of Sucker Control Practices on Growth and Cured-leaves of Local Tobacco Variety Hyangcho (곁순 억제방법이 재래연초 향초의 생육 및 건조엽에 미치는 영향)

  • 이철환;김용옥;이병철;조수헌
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.35 no.1
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    • pp.53-57
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    • 1990
  • Among the 6 treatment of not topped and suckered, topped and not suckered, hand suckered, maleic hydrazide treated, fatty alcohol treated to normal Hyangcho, and male sterile line, yield and Quality by price was lower at not topped and suckered, topped and not suckered or male sterile line plot. The content of petroleum ether extracts and ash was lower in hand suckered, maleic hydrazide and fatty alcohol plot, but the trends of reducing sugar, nicotine, and pH were in reverse. Reducing sugar was higher, nicotine and pH was lower in maleic hydrazide plot than in hand suckered or fatty alcohol plot. Filling value and combustibility was lower in maleic hydrazide plot than in hand suckered.

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Polymorphisms of 5, 10-Methylentetrahydrofolate Reductase (MTHFR C677T) and Methionine Synthase Reductase (MTRR A66G) as Maternal Risk Factors for Fetal Aneuploidy (태아의 염색체의 수적 이상을 유발하는 모계 위험인자로서 5, 10-Methylentetrahydrofolate Reductase (MTHFR C677T)와 Methionine Synthase Reductase (MTRR A66G) 유전자의 다형성 연구)

  • Kim, Do-Jin;Kim, Shin-Young;Park, So-Yeon;Kim, Jin-Woo;Kim, Moon-Young;Han, Joung-Yeol;Yang, Jae-Hyug;Ahn, Hyun-Kyong;Choi, Jun-Seek;Chung, Jin-Hoon;Ryu, Hyun-Mee
    • Journal of Genetic Medicine
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    • v.5 no.2
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    • pp.119-124
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    • 2008
  • Purpose: Aneuploidy is the cause of diseases such as Down syndrome or Edward syndrome and, more generally, is a major cause of mental retardation and fetal loss. The purpose of this study was to evaluate the association between MTHFR (C677T) or MTRR (A66G) polymorphisms and fetal aneuploidy. Materials and Methods: Data was collected from 37 women who had a fetus with aneuploidy (cases) and 78 women who had previously delivered at least two healthy children without aneuploidy and did not have a history of miscarriage or abnormal pregnancy (controls). The MTHFR (C677T) or MTRR (A66G) polymorphisms were analyzed by PCR-restriction fragment length polymorphism assay. Results: The frequencies of the MTHFR 677 CC, CT, and TT genotypes were 30.7%, 48.7%, and 20.6% in the control group and 37.8%, 48.6%, and 13.5% in the case group, respectively. There were no significant differences in genotype frequencies between the two groups. For the MTRR A66G polymorphism, the frequencies of the AA, AG and GG genotypes were 50%, 46.1%, and 3.9% in the control group and 13.5%, 81.1%, and 5.4% in case group, respectively. The frequency of the MTRR AG mutant was significantly increased in the case group, with an odds ratio of 6.5 (95% CI: 2.3-18.6, P<0.05). Conclusion: The results of this study suggest that mother carriers with the MTRR G allele have an increased risk of fetal aneuploidy, while the MTHFR T allele is not associated with increased risk of fetal aneuploidy. The MTRR A66G polymorphism may be a risk factor for producing a child with chromosomal aneuploidy.

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Generation of High-Resolution Chest X-rays using Multi-scale Conditional Generative Adversarial Network with Attention (주목 메커니즘 기반의 멀티 스케일 조건부 적대적 생성 신경망을 활용한 고해상도 흉부 X선 영상 생성 기법)

  • Ann, Kyeongjin;Jang, Yeonggul;Ha, Seongmin;Jeon, Byunghwan;Hong, Youngtaek;Shim, Hackjoon;Chang, Hyuk-Jae
    • Journal of Broadcast Engineering
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    • v.25 no.1
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    • pp.1-12
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    • 2020
  • In the medical field, numerical imbalance of data due to differences in disease prevalence is a common problem. It reduces the performance of a artificial intelligence network, leading to difficulties in learning a network with good performance. Recently, generative adversarial network (GAN) technology has been introduced as a way to address this problem, and its ability has been demonstrated by successful applications in various fields. However, it is still difficult to achieve good results in solving problems with performance degraded by numerical imbalances because the image resolution of the previous studies is not yet good enough and the structure in the image is modeled locally. In this paper, we propose a multi-scale conditional generative adversarial network based on attention mechanism, which can produce high resolution images to solve the numerical imbalance problem of chest X-ray image data. The network was able to produce images for various diseases by controlling condition variables with only one network. It's efficient and effective in that the network don't need to be learned independently for all disease classes and solves the problem of long distance dependency in image generation with self-attention mechanism.

최고의 전기설비 기술력으로 승부

  • 에너지절약전문기업협회
    • The Magazine for Energy Service Companies
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    • s.15
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    • pp.26-29
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    • 2002
  • ESCO 시장에서 수적으로 큰 비중을 차지하는 전기설비 분야에서 전문가라 자부하는 이들이 있다. 우수한 기술력을 바탕으로 견고한 기반을 구축해 온 이들이 적극적인 시장진출에 필요한 엔진을 장착했다. 전기설비 전문업체로 출발하여 1999년 ESCO 업체로 등록한 이후 꾸준한 성장세를 기록해 온 동남아전설㈜이 조명에 치중해 왔던 지금까지의 사업추진방식에서 벗어나 고효율보일러와 폐열회수장치 등으로 분야를 확장하고 있어 그 결과가 주목되고 있다.

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저작권에이전시 대부분이 개점휴업

  • Choe, Tae-Won
    • The Korean Publising Journal, Monthly
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    • s.80
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    • pp.8-9
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    • 1991
  • 1987년 새 저작권법이 발효됨에 따라 정식으로 선을 보이기 시작한 국내 저작권에이전시들이 활동이 아직까지 유명무실한 것으로 드러났다. 수적으로는 매년 성장세를 보이고 있으면서도, 구체적인 실적에 있어서는 두세개 에이전시를 빼고 나면 아예 개점휴업 상태에 놓여 있어, 앞으로 더욱 늘어날 해외 저작물 이용에 능동적으로 대처하기 어려우리라는 우려를 낳고 있다.

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Analysis and Solution of Small Libraries in Jeon-buk Province (전북지역 작은도서관의 현 단계와 기능 확대에 관한 연구)

  • Kim, Hong-Ryul
    • Journal of Korean Library and Information Science Society
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    • v.41 no.1
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    • pp.77-98
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    • 2010
  • Recently, small libraries have greatly increased by the support and interest of the central, or local government. Since 2004, 47 small libraries were established in Jeon-buk province. These libraries are equipping a new facility and collection with their support. Nevertheless, they still have many problems in operating process. This is causing degradation of the quality level of information service for local residents, further, this becomes the obstacle which solves a information divide and improves the cultural welfare. The purpose of this study is to analyze the status of small libraries in Jeon-buk province, and then, to propose solutions to problems.

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