• Title/Summary/Keyword: Confluence of Results

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Significance of Cerebral Venography in Surgery of Petroclival Meningiomas (추체사대 수막종의 수술과 관련하여 뇌 정맥조영상의 의미)

  • Hwang, Sung-Kyun;Gwak, Ho-Shin;Paek, Sun Ha;Oh, Chang-Wan;Lee, Sang Hyung;Kim, Dong Gyu;Kim, Hyun Jib;Jung, Hee-Won
    • Journal of Korean Neurosurgical Society
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    • v.30 no.10
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    • pp.1200-1209
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    • 2001
  • Objective : A thorough understanding of the related venous structure is mandatory for successful removal of the petroclival meningiomas. This study was planned to investigate the guideline for safe ligation and incision of transverse or sigmoid sinuses and the importance of drainage pattern of vein of $Labb{\acute{e}}$ in surgical removal of petroclival meningiomas. Patients and Methods : The authors reviewed the venogram of the consecutive 37 cases of petroclival meningiomas and retrospectively analyzed their surgical findings. The drainage pattern of confluence of Herophili was classified as Type A(confluent & equal on both sides), Type B(confluent & non-dominant on tumor side), Type C(confluent & dominant on tumor side) and Type D(unilateral drainage only) as these findings gave the information on safe ligation and resection of the sinus. Usefulness of intraoperative test clamping of sinus for safe ligation was also reviewed. The vein of $Labb{\acute{e}}$ was analyzed with respect to its draining point and its collaterals to other superficial veins. Results : Contraindications of the sinus ligation and resection according to the drainage pattern at the confluence of Herophili were Type C(n=10, 27%)and Type D(n=4, 11%). Patients with Type A(n=12, 32%)and Type B(n=11, 30%) were tolerable to sinus ligation ipsilateral to tumor, if the test clamping proved to be safe. Identification of no brain swelling, after intraoperative test clamping of the sinus for more than 30 minutes performed in 7 out of 11 cases, was a reliable indicator of safe sinus ligation. The drainage pattern of the vein of $Labb{\acute{e}}$, especially low-lying type, could predict the possibility of postoperative hemorrhage and infarction. Its drainage into tentorium or superior petrosal sinus, however, made the transtentorial approach impossible, leading to restricted operative field. Conclusion : For a successful removal of the petroclival meningiomas preoperative venogram should be examined carefully. The extent of exposure in a planned approach can be estimated by analyzing the variation of sinuses and the drainage pattern of vein of $Labb{\acute{e}}$.

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Exploration of Creativity Construction Components in Computer Science (정보과학 창의성의 구성 요소 탐색)

  • Yun, Seon-Hee;Kim, Yung-Sik
    • The Journal of Korean Association of Computer Education
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    • v.14 no.1
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    • pp.45-54
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    • 2011
  • Creativity is a fine ability among major values of human resource in knowledge-based society. The purpose of this study is to identify the components of the informatics creativity based on domain-specificity and confluence theory. To explore these components, a three-round, classical Delphi process was administered with an expert panel of 31 individuals. All members of the expert panel initially responded to open-ended questions, and the qualitative results were analyzed. The subsequent two rounds of the Delphi required quantitative responses in which the expert panel was asked to indicate the level of importance using a five point Likert scale associated with specific items. As a result of the Delphi survey, total of 32 items were selected as three core areas such as congnitive, affective and environmental components of informatics creativity.

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Measurement and Simulation Study of RSFQ OR gate

  • Nam, Doo-Woo;Jung, Ku-Rak;Hong, Hee-Song;Joonhee Kang
    • Progress in Superconductivity and Cryogenics
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    • v.5 no.1
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    • pp.44-47
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    • 2003
  • There are several simulation programs in studying superconductor RSFQ (Rapid Single flux Quantum) electronic devices, which include WRspice, WinS, PSCAN, and JSIM. Even though different research groups use different simulation programs, it is not well known about which program gives the simulation results closer to the measurement values. In this work, we used both WRspice and WinS to simulate RSFQ OR gate and to compare the results from the different simulations. This comparison would help in deciding which program is better in the RSFQ circuit design. In the confluence buffer, which is the one of the main components of the DR gate, the measured bias margins were ${\times}23.2%$, while the margins from the simulations were ${\pm}35.56%$ from WRspice and it 53.1% from WinS. However, with the actual fabricated circuit parameters WRspice gave ${\pm}27%$. In WinS the circuit did not operate. We concluded that WRspice is more reliable.

Analysis on Two Parallel Flows in Convergent Channel (축소 유로내의 두 평행 유동에 대한 해석)

  • Kwon, Jin-Kyung;Kim, Tae-Wook;Kim, Jin-Hyun;Kim, Jae-Yeol
    • Journal of the Korean Society of Propulsion Engineers
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    • v.10 no.4
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    • pp.11-18
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    • 2006
  • Compound flow by confluence of two parallel flows through a convergent channel and its choking phenomenon are calculated by one-dimensional isentropic model and completely mixing model. Optical observations and pressure measurements for subsonic/subsonic compound flows are carried out and compared with the results of one-dimensional calculations. As a result, it is found that inlet conditions of one flow influence the behavior of the other flow as well as the choking condition and present experimental data agree well with the results of one-dimensional calculations.

영산강 하상퇴적물의 중금속 함량

  • 조영길;김주용
    • Journal of Environmental Science International
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    • v.7 no.3
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    • pp.281-290
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    • 1998
  • Thirty-eight sediment samples collected from the Youngsan River channel were analysed for Fe, Mn, Co, Cr, Cu, Nl, Zn and Pb to recognize the extent of contamination. Results showed that a wide range of contents was apparent far every metal over the study area. These differences have been mainly related to the textural variability of sediments. Exceptions to this were fecund in the contents of Cu, Zn, Pb and possibly Mn. The contents of Cu, Zn, Pb and Mn were particularly higher in the sediments loom the confluence of tributaries. Downstream profile of metal/Al ratios indicates that pollutant inputs from the Kwangju tributary are mainly responsible for enrichment of these metals in bed sediments of the Young-san River.

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A Study on Epistemic Structure of the Architecture in Cyberspace. - A comparative analysis on Novak and Lynn based on Lacan's subject theory - (사이버공간의 인식적 구조에 관한 연구 - 라캉의 관점으로 본 노박과 린의 비교연구 -)

  • Lee Kyung-Hoon
    • Korean Institute of Interior Design Journal
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    • v.14 no.3 s.50
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    • pp.224-233
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    • 2005
  • Cyberspace is created through the confluence of global electronic communications networks and technology, and also meant to be a three-dimensional space of information. Its application in arts, however, requires broader views and knowledge and often results a confounded definition of it. The study is to define cyberspace and the architecture in it, with the methodology of the structural criticism, focusing the textuality without any impression or intuition to reach its valid epistemic definition. Two architects in cyberspace; Novak and Lynn, and their works have been discussed and analyzed reflecting Benedikt's theory of cyberspace which has coined its definition in architecture in early 90's. Lacan's subject theory, including the mirror stage, has played a key role to evaluate the identities and the differences of various views towards cyberspace. It also enables us to construe the on-going status and meaning of cyberspace and the architecture In it.

Effect of the Vibration Modes on the Radiation Sound for Plate (강판의 진동모드를 고려한 방사음 예측에 관한 연구)

  • Kim Chang-Nam;Byun Young-Su;Kim Jeong-Man;Kim Ue-Kan
    • Journal of Advanced Marine Engineering and Technology
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    • v.30 no.1
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    • pp.73-80
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    • 2006
  • In order to compute the radiated sound from a vibrating structure, the Rayleigh's integral equation has to be derived from the Helmholtz equation using Green's function. Generally, the surface velocity in the Rayleigh's integral equation uses the root mean square(rms) velocity. The calculation value is too large, because it's not considered cancelation. On the other hand. using the complex velocity, the sound pressure is calculated too small, because it considers that sound is perfectly canceled out. Therefore, this thesis proposes a correction factor(CF) which considers vibration modes and the method by which to calculate the radiating sound pressure. The theoretical results are compared with the experimental values, and the proposed method can be verified with confluence.

Study on Rainfall Characteristics for the Millimeter-wave Communication Systems-Comparisons of Rainfall rate data from Several observation methods.

  • Chung, H.S.;Song, B.H.;Lee, J.H.;Park, K.M.;Lee, K.A.
    • Proceedings of the KSRS Conference
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    • 1999.11a
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    • pp.132-134
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    • 1999
  • Rainfall characteristics for designing the optimum millimeter-wave communication systems from two rainfall data set was analyzed. Two rainfall data sets were compared; one-minute rainfall rate data, one-hour synoptic observation data. Each data set has different observation method, sampling frequency. We looked for tendency and quality confluence between two data sets. We showed several results using one-minute rainfall data by millimeter-wave attenuation model. A climatological one-minute rainfall rate data set over Korean Peninsula will be made after data quality control procedure

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Application of Dry/Wet Algorithm for 2-Dimensional Flow Analysis (2차원 흐름해석을 위한 마름/젖음 알고리듬의 적용)

  • Han, Kun-Yeun;Kim, Sang-Ho;Choi, Seung-Yong;Lee, Su-Chang
    • Proceedings of the Korea Water Resources Association Conference
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    • 2008.05a
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    • pp.629-633
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    • 2008
  • Frequently occurring flood and drought have increased the necessity of an effective water resources control and management of river flows. Therefore, the simulation of the flow distribution in natural rivers is very important to the solution of a wide variety of practical flow problems in water resources engineering. Usually in many flow problems, two-dimensional approach can provide good estimates of complex flow features in the flow around islands and obstructions, flow at confluence and flow in braided channel. The objective of this study is to examine validation of developed an accurate and robust two-dimensional finite element method with wet and dry simulation in complex natural rivers. Milyang river, and Kumho river and Keum river were performed for tests. The results were compared with those of existing model. The suggested model displayed reasonable flow distribution compared with existing model in dry area for application of natural river flow. As a result of this study, the developed general two-dimensional model provide a reliable results for flow distribution of wet and dry domain, it could be further developed to basis for extending to water quality and sediment transport analysis.

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Effects of TGF-$\beta$3 on Epithelial-mesenchymal transformation and Epidermal growth factor receptor expression in palatogenesis of chicken embryo (계태아 발생시 TGF-$\beta$3가 구개판 내측돌기상피의 상피간엽변환 및 상피성장인자수용체 발현에 미치는 영향)

  • Yang Byoung-Eun;Lee Jong-Ho
    • Korean Journal of Cleft Lip And Palate
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    • v.4 no.1
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    • pp.13-26
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    • 2001
  • Cleft lip and/or palate is the congenital orofacial malformation most commonly occurred in humans, The disease is multifactorial and is probably caused by genetic and/or environmental factors, So, there are many problems in research concerning etiology and in treatment of the disease, Even the most practiced and sophisticated methods of surgical repair are necessarily followed by scar contraction and fibrosis, which result in skeletal defects, dental abnormalities, cosmetic disfigurement, and speech impairment, As a result, Fetal surgery can be considered but practiced rarely when the deformity is not fatal to life, And treatment of cleft palate is performed in the form of medicine projection into uterus in animal experiments, Many studies show that growth factor and its receptor emerge from the developing palate; and the epidermal growth factor receptors have a important role in craniofacial development and in palatal fusion, The palatal morphogenesis of the avine is different from the mammal's; it takes the form of physiologic cleft palate, Recently, cleft palate fusion experiment was performed when the avine were in the period of palate formation through the exogenous TGF-β3 addition, and it showed that the exogenous TGF-β3 makes fusion of divided palate through certain process when cleft palate is occurred in palatal formation, In this study, I had the conformation of the fusion of cleft palate through the addition of TGF-β in case of chicken embryo, and observed the effect of TGF-β in EGF receptor distribution, And the following is the results of this study, 1. In case of the TGF-βl and β3 addition group, there was the decrease of EGFR(Epidermal Growth Factor Receptor) immunoreactivity in mesenchymal cells beneath the medial edge epithelium and also in epithelial mesenchymal interface which is between medial edge epithelium and nasal septum in 72 hours, 2, The immunoreactivity of the control group resembles that of normal chicken embryo palate in development, 3. In the view through fluorescence confocal microscopy, there was confluence in TGF-β3 addition group, This shows that the confluence induced by exogenous TGF-β3 is related to EGFR expression in palate of chicken embryo, which is a physiologic cleft palate model.

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