해안선을 따라 이동하는 켈빈파의 회전수조 모형 실험

蘇鮮變,金明煥,許相旭,李惠眞,梁潤實 공주대학교 기초과학연구소 2000 自然科學硏究 Vol.9 No.-

켈빈파란 회전계의 북반구에서 육지를 오른쪽에 두고 해안선을 따라 이동하는 파이다. 이 켈빈파를 가시화하기 위해 밀도차를 갖는 두 층의 유체를 만들고 경계면에 생기는 내부캘빈파를 가시화하여 변화를 관찰하였다. 지금까지는 해안가에서 나타나는 밀물과 썰물을 단순히 달의 인력으로 인한 조석으로만 생각했었는데, 본 실험을 통하여 그것이 지구자전의 영향을 받아 회전하는 조석파임을 알게되었다. Kenvin wave moves along the shoreline from the Northern hemisphere of rotating system in right of the land. Yeu observe s veriety for the visibity of it, we make two layers to have divergence of density, then it is visible the interior of Kelvin wave in a boundary plane. You thought simply the ebb and flow of the tide that they was the tidal movement to be due to the gravitation of the moon on the shore. But we know that Kelvin wave is rotating tide wave affected by revolution of the earth.

Polymerization of dual cured composites by different thickness

Kim, Yun Ju,Jin, Myoung Uk,Kim, Sung Kyo,Kwon, Tae-Yub,Kim, Young Kyung 大韓齒科保存學會 2008 Restorative Dentistry & Endodontics Vol.33 No.3

본 연구는 이중 중합형 복합레진에서 재료의 두께, 충전방법 및 중합방법에 따른 중합도를 미세경도 시험을 이용하여 측정하고자 하였다. 이중 중합형 복합레진으로는 MultiCore Flow (Ivovlar Vivadent AG, Schaan, Liechtenstein)와 Bis-Core (Bisco Inc., Schaumburg IL, USA)를 사용하였다. 시편의 제작은 각각 두께가 2 (단일충전), 4 (단일충전), 6 (단일충전과 적층충전), 8 (단일충전과 적층충전) ㎜의 Teflon mold에 재료를 주입한 다음 할로겐 광중합기 (Optilux 501, Kerr, Danbury, USA)를 사용하여 광중합하거나 암실에서 30분 동안 기다린 후(자가 중합) Teflon mold에서 제거하였다. 제거한 시편은 37℃ 증류수에 24시간 동안 보관한 후 각 시편의 윗면과 아랫면을 2000번 연마제와 PoGo system (Dentsply, Konstanz, Germany)을 이용하여 마무리하였다. Digital microhardness tester (FM-7, Future-Tech Corp., Tokyo, Japan)를 이용하여 경도값(Knoop hardness number)을 측정하였으며 윗면의 경도값/아랫면의 경도값을 이용하여 경도비를 계산하였다. 계측치는 one-way ANOVA로 통계 분석 후 사후검정은 Scheffe 다중비교법을 이용하였다. 이중 중합형 복합레진의 중합도에 대한 두께의 영향을 보면 재료에 따라 다른 결과를 보였다. 2, 4, 6 ㎜ 군에서는 MulriCore Flow와 Bis-Core 모두 두께에 의한 영향을 받지 않았지만 8 ㎜ 군에서는 MultiCore Flow의 아랫면에서 다른 두께의 군보다 낮은 경도값을 보였다. 충전방법에 따른 중합도의 차이를 보면, 재료의 두께나 재료에 따라 다른 결과를 보였다. 6 ㎜ 군에서는 단일충전군과 적층충전군 사이에 차이를 보이지 않았으나, 8 ㎜ 군에서는 Bis-Core에서는 차이가 없는 반면 MultiCore Flow에서 는 단일충전한 군이 적층충전한 군보다 낮은 경도비를 보였다. 중합방법에 따른 중합도의 차이를 보면, 재료에 따라 다른 결과를 보였다. Bis-Core의 경우에는 윗면과 아랫면 모두에서 이중 중합 시킨 군이 자가 중합 시킨 군보다 높은 경도값을 보였다. 그러나 MultiCore Flow의 경우, 윗면에서는 이중중합 시킨 군이 더 높은 경도간을 보였지만 아랫면에서는 더 낮은 값을 보였다. 따라서 본 연구의 결과에 따르면 코어용 이중 중합형 복합레진을 깊은 와동에 충전할 경우 적층충전이 추천되며, 또한 광중합을 해 줌으로써 더 좋은 물리적 성질을 기대할 수 있을 것으로 사료된다. The purpose of this study was to evaluate the effect of thickness, filling methods and curing methods on the polymerization of dual cured core materials by means of microhardness test. Two dual cured core materials, MultiCore Flow (Ivoclar Vivadent AG, Schaan, Liechtenstein) and Bis-Core (Bisco Inc., Schaumburg, IL, USA) were used in this study. 2 ㎜ (bulky filled), 4 ㎜ (bulky filled), 6 ㎜ (bulky and incrementally filled) and 8 ㎜ (bulky and incrementally filled)-thickness specimens were prepared with light cure or self cure mode. After storage at 37℃ for 24 hours, the Knoop hardness values (KHN) of top and bottom surfaces were measured and the microhardness ratio oftop and bottom surfaces was calculated. The data were analyzed using one-way ANOVA and Scheffe multiple comparison test, with α = 0.05. The effect of thickness on the polymerization of dual cured composites showed material specific results. In 2, 4 and 6 ㎜ groups, the KHN of two materials were not affected by thickness. However, in 8 ㎜ group of MultiCore Flow, the KHN of the bottom surface was lower than those of other groups (p < 0.05). The effect of filling methods on the polymerization of dual cured composites was different by their thickness or materials. In 6 ㎜ thickness, there was no significant difference between bulk and incremental filling groups. In 8 ㎜ thickness, Bis-Core showed no significant difference between groups. However, in MultiCore Flow, the microhardness ratio of bulk filling group was lower than that of incremental filling group (p < 0.05). The effect of curing methods on the polymerization of dual cured composites showed material specific results. In Bis-Core, the KHN of dual cured group were higher than those of self cured group at both surfaces (p < 0.05). However, in MultiCore Flow, the results were not similar at both surfaces. At the top surface, dual cured group showed higher KHN than that of self cured group (p < 0.05). However, in the bottom surface, dual cured group showed lower value than that of self cured group (p < 0.05).

A case of tacrolimus-induced encephalopathy after kidney transplantation

Kim, Myoung-Uk,Kim, Sae-Yoon,Son, Su-Min,Park, Yong-Hoon The Korean Pediatric Society 2011 Clinical and Experimental Pediatrics (CEP) Vol.54 No.1

We present a case of tacrolimus-induced encephalopathy after successful kidney transplantation. An 11-year-old girl presented with sudden onset of neurologic symptoms, hypertension, and psychiatric symptoms, with normal kidney function, after kidney transplantation. The symptoms improved after cessation of tacrolimus. Magnetic resonance imaging (MRI) showed acute infarction of the middle cerebral artery (MCA) territory in the right frontal lobe. Three days later, she had normal mental function and maintained normal blood pressure with left hemiparesis. Follow-up MRI was performed on D19, showing new infarct lesions at both cerebral hemispheres. Ten days later, MRI showed further improvement, but brain single photon emission computed tomography (SPECT) showed mild reduction of uptake in both the anterior cingulate gyrus and the left thalamus. One month after onset of symptoms, angiography showed complete resolution of stenosis. However, presenting as a mild fine motor disability of both hands and mild dysarthria, what had been atrophy at both centrum semiovale at 4 months now showed progression to encephalomalacia. There are two points of interest in this case. First, encephalopathy occurred after administration of tacrolimus and improved after discontinuation of the drug. Second, the development of right-side hemiplegia could not be explained by conventional MRI; but through diffusion tensor imaging (DTI) and diffusion tensor tractography (DTT) of white matter tract, visualization was possible.

Proximity of the mandibular molar root apex from the buccal bone surface: a cone-beam computed tomographic study

Kim, Dokyung,Ha, Jung-Hong,Jin, Myoung-Uk,Kim, Young-Kyung,Kim, Sung Kyo The Korean Academy of Conservative Dentistry 2016 Restorative Dentistry & Endodontics Vol.41 No.3

Objectives: The purpose of this study was to evaluate the proximity of the mandibular molar apex to the buccal bone surface in order to provide anatomic information for apical surgery. Materials and Methods: Cone-beam computed tomography (CBCT) images of 127 mandibular first molars and 153 mandibular second molars were analyzed from 160 patients' records. The distance was measured from the buccal bone surface to the root apex and the apical 3.0 mm on the cross-sectional view of CBCT. Results: The second molar apex and apical 3 mm were located significantly deeper relative to the buccal bone surface compared with the first molar (p < 0.01). For the mandibular second molars, the distance from the buccal bone surface to the root apex was significantly shorter in patients over 70 years of age (p < 0.05). Furthermore, this distance was significantly shorter when the first molar was missing compared to nonmissing cases (p < 0.05). For the mandibular first molars, the distance to the distal root apex of one distal-rooted tooth was significantly greater than the distance to the disto-buccal root apex (p < 0.01). In mandibular second molar, the distance to the apex of C-shaped roots was significantly greater than the distance to the mesial root apex of non-C-shaped roots (p < 0.01). Conclusions: For apical surgery in mandibular molars, the distance from the buccal bone surface to the apex and apical 3 mm is significantly affected by the location, patient age, an adjacent missing anterior tooth, and root configuration.

Thermal Properties and Isothermal Crystallization Kinetics of Surface-Modified Multi-walled Carbon Nanotubes Reinforced Poly(phenylene sulfide) Composites

Myoung-Uk KIM,Jung-Min LEE,Hyun-Gyoo ROH,Hyeon-Jeong KANG,Soo-Hee PARK,Da-Hyun KIM,Ju-Hee BYEON,Se-Jun OH,Jong-Su LEE,Jong-Shin PARK 한국고분자학회 2016 한국고분자학회 학술대회 연구논문 초록집 Vol.41 No.2

All-optical image switching in a double-λ system.

Kim, Bongjune,Oh, Cha-Hwan,Sohn, Byoung-uk,Ko, Do-Kyeong,Kim, Hyung Tak,Jung, Changsoo,Oh, Myoung-Kyu,Yu, Nan Ei,Kim, Bok Hyeon,Kang, Hoonsoo Optical Society of America 2013 Optics express Vol.21 No.12

<P>The coherent control of optical images has garnered attention because all information embedded in optical images is expected to be controlled in a parallel way. One of the most important control processes is switch for information delivery. We experimentally demonstrated phase-controlled optical image switching in a double-λ system where the transmission of the image through a medium was switched. Two independent laser sources were adopted for a double-λ system such that images inscribed in two weak probe light beams were incoherent with each other. Arbitrary phase was added to the optical images to show that switching could be accomplished just with the relative phase difference between the probe pixels.</P>

Genome‐scale analysis of <i>Mannheimia succiniciproducens</i> metabolism

Kim, Tae Yong,Kim, Hyun Uk,Park, Jong Myoung,Song, Hyohak,Kim, Jin Sik,Lee, Sang Yup Wiley Subscription Services, Inc., A Wiley Company 2007 Biotechnology and bioengineering Vol.97 No.4

<P><B>Abstract</B></P><P><I>Mannheimia succiniciproducens</I> MBEL55E isolated from bovine rumen is a capnophilic gram‐negative bacterium that efficiently produces succinic acid, an industrially important four carbon dicarboxylic acid. In order to design a metabolically engineered strain which is capable of producing succinic acid with high yield and productivity, it is essential to optimize the whole metabolism at the systems level. Consequently, in silico modeling and simulation of the genome‐scale metabolic network was employed for genome‐scale analysis and efficient design of metabolic engineering experiments. The genome‐scale metabolic network of <I>M. succiniciproducens</I> consisting of 686 reactions and 519 metabolites was constructed based on reannotation and validation experiments. With the reconstructed model, the network structure and key metabolic characteristics allowing highly efficient production of succinic acid were deciphered; these include strong PEP carboxylation, branched TCA cycle, relative weak pyruvate formation, the lack of glyoxylate shunt, and non‐PTS for glucose uptake. Constraints‐based flux analyses were then carried out under various environmental and genetic conditions to validate the genome‐scale metabolic model and to decipher the altered metabolic characteristics. Predictions based on constraints‐based flux analysis were mostly in excellent agreement with the experimental data. In silico knockout studies allowed prediction of new metabolic engineering strategies for the enhanced production of succinic acid. This genome‐scale in silico model can serve as a platform for the systematic prediction of physiological responses of <I>M. succiniciproducens</I> to various environmental and genetic perturbations and consequently for designing rational strategies for strain improvement. Biotechnol. Bioeng. 2007;97: 657–671. © 2007 Wiley Periodicals, Inc.</P>

타 시스템과 연계를 통한 용지보상 업무 자동화 방안 연구

서명배(Myoung-Bae Seo),김진욱(Jin-Uk Kim),김병곤(Byoung-Gon kim),김성진(Seong-Jin Kim) (사)한국CDE학회 2008 한국 CAD/CAM 학회 학술발표회 논문집 Vol.2008 No.1

혼합형 안전주입탱크의 압력평형 예측을 위한 열손실 평가

김명준(Myoung Jun Kim),류성욱(Sung Uk Ryu),김재민(Jae Min Kim),박현식(Hyun-Sik Park),이성재(Sung-Jae Yi) 한국에너지학회 2017 에너지공학 Vol.26 No.3

피동고압충수용 혼합형 안전주입탱크 내부 열전달 분석

김명준(Myoung Jun Kim),김재민(Jaemin Kim),류성욱(Sung Uk Ryu),박현식(Hyun-Sik Park),이성재(Sung-Jae Lee) 대한기계학회 2016 대한기계학회 춘추학술대회 Vol.2016 No.12

When the reactor coolant system is in high pressure condition such as station black out (SBO) accidents, the cooling water must be supplied smoothly by gravity force without active components. In accordance with these requirements, the Hybrid Safety Injection Tank (Hybrid SIT) system is suggested by the Korea Atomic Energy Research Institute (KAERI) for the passive emergency core cooling system (PECCS). The Hybrid SIT and pressurizer is connected to the pressure balancing line (PBL) to cope with high pressure accident scenarios. In order to consider the thermal-hydraulic phenomena of the Hybrid SIT, the heat transfer characteristics inside the Hybrid SIT should be evaluated. In this study, a heat transfer method using experimental data has been proposed for the quantification of heat and condensation ratio. From the analytical investigations, it is found that the wall heat transfer is the most dominant mechanism for the present Hybrid SIT.