• Journal of Korean Neurosurgical Society
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• 제63권3호
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• pp.327-337
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• 2020

Junctional neurulation represents the most recent adjunct to the well-known sequential embryological processes of primary and secondary neurulation. While its exact molecular processes, occurring at the end of primary and the beginning of secondary neurulation, are still being actively investigated, its pathological counterpart -junctional neural tube defect (JNTD)- had been described in 2017 based on three patients whose well-formed secondary neural tube, the conus, is widely separated from its corresponding primary neural tube and functionally disconnected from corticospinal control from above. Several other cases conforming to this bizarre neural tube arrangement have since appeared in the literature, reinforcing the validity of this entity. The cardinal clinical, neuroimaging, and electrophysiological features of JNTD, and the hypothesis of its embryogenetic mechanism, form part of this review.

• 한국대기환경학회지
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• 제19권5호
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• pp.541-549
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• 2003

A basic experimental study was conducted in order to find the optimum combustion control technology to decrease the thermal NO$_{x}$, by applying the catalytic combustion method with natural gas. NO$_{x}$ emission increased with increasing space velocity due to temperature rising in the furnace. In order to overcome the low resistance to high temperature, secondary air was supplied to the CST combustor. The following secondary fuel formed combustible mixture in part, which resulted in steep increase of the exiting temperature of the 2nd catalyst bed. It led to the more generator of NO$_{x}$, 30∼60% of the 1 st catalyst bed. It might be due to the potential increase of thermal NO$_{x}$.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집B
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• pp.467-472
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• 2000

Most of the past experimental or analytical studies were performed for the curved bend with a square cross-section. Velocity profiles and Reynolds stresses of the turbulence flow in the 270 degree bend with circular cross-section were measured by a hot-wire anemometer. The mean velocity of primary flowing direction effected by the downstream of bend in the entry region of the bend. The flow in the inner part of the bend slowed the distribution velocity relatively large and unsymmetric phenomenon. In the strong secondary flow occurred when the flow passed in the region of 45 degree to 90 degree. The secondary flow appeared very large value in the neighbor region of inner wall.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제18권3호
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• pp.209-221
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• 2014

In the last few decades there has been much interest in how mathematics can be effectively taught and learnt. The Third Wave is a unique ongoing international collaborative mathematics education research project, which aims to explore the relevant values of effective school mathematics teaching from both the teacher and student perspectives. As part of this project, this study investigates the related findings from students on the Chinese mainland. Multiple data were collected through classroom observations, focus group interviews, and written, open-ended questions. Twenty-four students from junior and senior secondary schools were invited to write down their views on an effective lesson, a good mathematics teacher, and how to do well in mathematics learning. Results showed that among the eight values determined in the study, the values of involvement, explanation, and examples were embraced by students across all grades. Students preferred teacher-led mathematics teaching. Junior secondary students placed more value on teachers' personalities, whereas senior students placed more value on teachers' teaching manners.

• 대한한의학원전학회지
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• 제23권5호
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• pp.55-66
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• 2010

The medicinal part of Treasured Mirror of Eastern Medicine("東醫寶鑑" "湯液編") is based on Classified Emergency Materia Medica("證類本草"), Compendium of Prescriptions from the Countryside("鄕藥集成方"). But it distinguished materia medica of countryside(鄕藥) from materia medica of China(唐藥) and properly selected the sentences of them by actual medical circumstances in Korean peninsula. Especially upon assortment of medical herbs, the medicinal part of Treasured Mirror of Eastern Medicine added the part of Water, Earth, Metal, and divided the part of Fish & Bug, Jade & Stone into Fish, Bug, Jade, Stone part. Moreover, it abolished the three grade classification adopted in Classified Emergency Materia Medica, Compendium of Prescriptions from the Countryside and attempted a new approach on itemization; 'representative herb' and 'secondary herb'. Hence, medicinal part of Treasured Mirror of Eastern Medicine should be evaluated as the 'settling in of Chinese medicine with autonomous interpretation, other than 'the fusion of prescriptions from countryside and Chinese medicine.

• Journal of the Korean Wood Science and Technology
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• 제48권4호
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• pp.569-576
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• 2020

This study investigated the characteristics of microfibril angle(MFA) in order to see if there was any difference in pine tree lumber quality among the three mountain areas surrounding the Taebaek Mountains in Korea - Yeongdong (Goseong-gun), Yeongseo (Hongcheon-gun) and Yeongnam (Bonghwa-gun). Pine trees of each mountain area were divided into earlywood and latewood in relation to heartwood part (1959 ~ 1961, 3 annual rings) and sapwood part (2002 ~ 2004, 3annual rings), and measured at tangential section. The microfibril angle showed significant differences between mountain areas. In general, Goseong Mountain was found to have 37.35°, followed by Hongcheon Mountain 32.42° and Bonghwa Mountain 25.75°, in order. The sapwood part had larger angle than heartwood part; and earlywood, than latewood. Variation within a single annual ring tended to be smaller from earlywood toward latewood.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1999년도 봄 학술발표회 논문집
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• pp.373-380
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• 1999

Consolidation settlements of soft clay are often large and potentially damaging to the structures. Currently, large-scale construction projects for airport and harbor etc. are in progress in Korea and many of these structures will be constructed on thick and soft clay layers. For this kind of ground condition, evaluation of consolidation settlement is required at every design and construction stages, and the magnitude of secondary compression appears to be larger than expected. Generally, the magnitude of secondary compression is evaluated by laboratory and in-situ consolidation tests or by empirical $C_{a/}$ $C_{c}$, relationship. The use of empirical value $C_{a/}$ $C_{c}$ may be economical, fast and powerful tool in estimating secondary consolidation settlement. However, the databases of the $C_{a/}$ $C_{c}$, for typical soft clays in Korea are insufficient. The purpose of this study is to investigate the relationship of $C_{a/}$ $C_{c}$ on marine clay near the southern sea in Korea. A series of incremental loading consolidation tests with measurement of pore water pressure were performed. It was found that the $C_{a/}$ $C_{c}$ of undisturbed marine clay is 0.0397. This value is similar to that proposed by Mesri and Castro(1987) on inorganic clay and silt. and silt. and silt.

• 한국항공우주학회지
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• 제37권4호
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• pp.336-343
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• 2009

터빈 익렬 내의 2차유동손실은 터빈 익렬에서 발생하는 전체 공기역학적 손실의 30~50% 차지한다. 따라서 터빈 효율 향상에 있어 개선해야 될 중요한 부분으로 인식되고 있다. 또한, 과거부터 2차유동에 의한 손실을 줄이기 위한 많은 연구들이 수행되어졌다. 본 논문에서는 2차유동손실을 일으키는 요인 중의 하나인 말굽와류의 강도를 감쇄시키기 위해 일반적인 날개 앞전에 판을 설치하였으며, 판의 설치 높이 및 길이 등의 형상변수에 따라 발생된 말굽와류의 특성에 대해 연구하였다. 연구를 위해 $FLUENT^{TM}$를 이용하였다. 그리고 기준 모델의 경우보다 전압력 손실 계수가 약 4.0% 향상되었다.

• 대한기계학회논문집B
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• 제22권1호
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• pp.12-24
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• 1998

The paper presents the mechanism of secondary flows and the associated total pressure losses occurring in turbine cascades with turning angle of about 127 and 77 degree. Velocity and pressure measurements are taken in seven traverse planes through the cascade passage using a prism type five hole probe. Oil-film flow visualization is also conducted on blade and endwall surfaces. The characteristics of the limiting streamlines show that the three dimensional separation is an important flow feature of endwall and blade surfaces. The larger turning results in much stronger contribution of the secondary flows to the loss developing mechanism. A large part of the endwall loss region at downstream pressure side is found to be very thin when compared to that of the cascade inlet and suction side endwall. Evolution of overall loss starts quite early within the cascade and the rate of the loss growth is much larger in the blade of large turning angle than in the blade of small turning angle.

• 한국산림과학회지
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• 제30권1호
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• pp.42-49
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• 1976

참싸리 부위별 과산화동위효소형의 변이를 알고저 전기영동법에 의하여 효소형을 조사한 바, 동일 개체에서 동시에 채취한 동일부위의 과산화동위효소형의 변이는 없었으며 공동출현 "밴드"는 부위별로 차이가 있어 잎, 인피, 세근에서는 7번"밴드"자방에서는 35번"밴드"가 나타났으며 부위별 개체별 과산화동위효소형의 변이가 있었고 성숙된 잎을 제외하고는 개체간 과산화동위효소형의 색정농도에 차이가 있었다.