• International Journal of Aeronautical and Space Sciences
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• v.15 no.1
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• pp.91-96
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• 2014

The aim of this work is to determine supersonic nozzle profiles that are used in propulsion, for launchers or embarked with satellites. This design has the role of firstly, providing important propulsion, i.e. with uniform and parallel flow at exit; and secondly, to find short length profiles, without modification of the flow in the nozzle. The first elaborate program is used to determine the profile of the divergent, by using the characteristics method for an axisymmetric flow. The second program is conceived by using the finite volume method, to determine and test the profile found connected to a convergent.

• Journal of Korean Ophthalmic Optics Society
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• v.9 no.1
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• pp.75-79
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• 2004

Some ocular complications were connected to the contamination by the contact lens related. Especially the most cause of ocular complications was a microorganism from several processing of infections. Therefore the patients stopped the contact lens wear immediately by the side effects of ocular pathology. We had analyzed the microorganism from the laboratory. It was identified as mixed growth of the Chryseamonas meningosepticum and Enterobacter sp.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.69
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• pp.179-199
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• 2016

There is legal relation between both parties after contract formation. The parties are liable for performing each duties but a party is not liable for a failure to perform the duties if party proves that the failure was due to the force majeure. The forec majeure has different concepts and legal principles such as change circumstance, hardship, frustration, impediment and so on. Therefore, it need to analyze a historical background and their presence in various domestic legal systems. Although the CISG describes Art. 79 impediment instead of using the force majeure, the impediment has several interpretative limitation. The CISG pursue to harmonize divergent legal concepts and principles from various national laws and legal systems but the harmonization of legal systems make the impediment more confused. The article goes on to analyzes about limitation of the impediment and reviews to examine the force majeure and hardship in PICC. Thus both parties of international contract insert hardship clause in order to prevent the problem of judgment in a court or a court of arbitration under impediment of CISG.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.32 no.6
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• pp.81-86
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• 2004

Between rolling airframe missile and swirling propulsion jet passing through convergent-divergent nozzle of the rocket motor, occur exchanges of angular momentum which result in the increase of roll speed of the missile. This phenomena in called jet roll damping. In the study jet roll damping was formulated from conservation equation of angular momentum. And the maximum value of the jet roll damping of KPSAM was estimated with assumed swirl velocity distribution at nozzle exit and compared with result of computation of axisymmetric compressible turbulent nozzle flow.

• Journal of Korean Neurosurgical Society
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• v.42 no.6
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• pp.495-498
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• 2007

Fractures of lumbo-sacral junction involving bilateral sacral wings are rare. Posterior lumbo-sacral fixation does not always provide with sufficient stability in such cases. Various augmentation techniques including divergent sacral ala screws, S2 pedicle screws and Galveston rods have been reported to improve lumbo-sacral stabilization. Galveston technique using iliac bones would be the best surgical approach especially in patients with bilateral comminuted sacral fractures. However, original Galveston surgery is technically demanding and bending rods into the appropriate alignment is time consuming. We present a patient with unstable lumbo-sacral junction fractures and comminuted U-shaped sacral fractures treated by lumbo-sacro-pelvic fixation using iliac screws and discuss about the advantages of the iliac screws over the rod system of Galveston technique.

• 한국연소학회:학술대회논문집
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• 2005.10a
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• pp.261-267
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• 2005

A comprehensive DES quality numerical analysis has been carried out for reacting flows in constant-area and divergent scramjet combustor configuration with and without a cavity. Transverse injection of hydrogen is considered over a broad range of injection pressure. The corresponding equivalence ratio of the overall fuel-air mixture ranges from 0.167 to 0.50. The work features detailed resolution of the flow and flame dynamics in the combustor, which was not typically available in most of the pervious studies. Much of the flow unsteadiness is related not only the cavity, but also to the intrinsic unsteadiness in the flowfield. The interactions between the unsteady flow and flame evolution may cause a large excursion of flow oscillation. The roles of the cavity, injection pressure, and heat release in determining the flow dynamics are examined systematically.

• Korean Journal of Plant Taxonomy
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• v.37 no.4
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• pp.351-361
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• 2007

In angiosperms, leaves typically develop as three-dimensional structure with dorsoventral, longitudinal, and lateral axes. We have shown that the control of two axes of leaves, longitudinal and lateral axis, can be genetically separable, and four classes of genes are responsible for the polar cell expansion and polar cell proliferation in Arabidopsis. In monocots, unifacial leaf, in which leaf surface consists only of abaxial identity, has been evolved in a number of divergent species. The unifacial leaves provide very unique opportunities for the developmental studies of the leaf axes formation in monocots, because their leaf polarities are highly disorganized. In addition, the mechanism of the parallel evolution of such drastic changes in leaf polarities is of interest from an evolutionary viewpoint. In this article, we describe our recent approaches to reveal the mechanism of unifacial leaf development and evolution, including recent advances in the leaf polarity specification in angiosperms.

• Journal of the Korean Chemical Society
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• v.39 no.10
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• pp.789-798
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• 1995

The silanedendrimer with 64 allylic end groups was prepared via a divergent growth approach. The reaction path of the repetitive alkenylation and hydrosilylation cycles was monitored by NMR spectroscopic analysis. Each of the two steps provided almost quantitative yields of pure dendrimers.

• Wind and Structures
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• v.8 no.2
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• pp.135-146
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• 2005

Divergent galloping-like motion of a dry inclined cable has been observed in a limited number of experimental studies, which, due to the uncertainties in its onset conditions, has induced serious concerns in the bridge stay cable design. A series of dynamic and static model wind tunnel tests have been carried out to confirm the existence of the phenomenon and clarify its excitation mechanism. The present paper focuses on exploring the spatial flow structure around an inclined cable. The pattern of resultant aerodynamic forces acting at different longitudinal locations of the model and the spatial correlation of the forces are examined. The results lead one step closer in revealing the physical nature of the phenomenon.

• Korean Journal of Child Studies
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• v.13 no.2
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• pp.241-249
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• 1992

본 연구는 그룹시간 동안의 한국 유치원 교사들의 질문양식과 유치원 아동들의 반응양식을 조사한 것이다. 본 연구를 위해서 12명의 유치원 교사와 중산층 가정에서 온 아동들이 12집단(남아 : 211명, 여아 : 176명) 참가했다. 비디오를 통해서 12명의 교사들의 질문양식과 각 집단의 아동들의 반응양식이 각각 3번씩 그룹시간의 처음 15분 동안 녹음되었다. 본 연구의 측정도구로서는 Aschner-Gallagher의 분류법이 사용되었고 통계분석방법은 Chi-square tests가 사용되었다. 또 교사들과 아동들의 연령 및 정보 등을 조사하기 위해서 교사들에게 질문지가 주어졌다. 본 연구의 결과는 교사들 사이에서 사용된 질문의 수준은 차이가 있었다는 것을 보여 주었다. (1) 교사들의 Congnitive Memory 질문을 가장 많이 사용했고 Evaluative 질문을 가장 적게 사용했다. (2) Congnitive Memory 질문을 가장 많이 사용한 교사들이 있는 반면에 Routine 질문을 가장 많이 사용한 교사들이 있었다. (3) Convergent 질문을 많이 사용한 교사들과 거의 사용하지 않은 교사들이 있었다. (4) Evaluative 질문 또는 Divergent 질문을 전혀 사용하지 않은 교사들이 있었다.