• Journal of the Korea Institute of Military Science and Technology
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• v.12 no.4
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• pp.415-423
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• 2009

To investigate low frequency acoustic transmissions in the Sub-Polar Front(SPF) of the East Sea, numerical experiments are conducted with Range dependent Acoustic Model(RAM) using Circulation Research of the East Asian Marginal Seas(CREAMS) data and Autonomous Profiling Explorer(APEX)) data. Significant seasonal variations of sea water properties are existed across the Sub-Polar Front(SPF) region from the north and the south. The model results show that Transmission Loss(TL) decrease(about 20dB) with ideal front in the warm region whereas TL increase(about 25dB) with ideal front in the cold region. Regardless of season(both in summer and winter), when the sound source is located in the cold region of the SPF, the model results show weak TL, compared to the case of the source in the warm region(Maximum difference of TL reaches 28dB). This difference between the cases when the source is located in the cold region and the warm region, is accounted for from the different vertical profiles of sound speed in both regions.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.747-752
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• 2003

Many clinical studies have suggested that the blood flow in ideal geometry is involved in the development of atherosclerosis. This study simulated blood flow in the abdominal artery with real geometry to investigate MWSS(mean wall shear stress), AWSS(amplitude of wall shear stress) and OSI(oscillator shear index). The calculation grid for the real geometry was constructed by extracting the surface of arterial wall from CT(Computed Tomography) or MRI(Magnetic Resonance Imaging) sheets called as DICOM (Digital Imaging and Communications in Medicines). The calculated MWSS, AWSS and OSI are much different from those of ideal geometry calculation. The MWSS increased while the AWSS decreased. Many shear forces are related to shapes of gradient. This paper will give clinical datum where the MWSS, AWSS and OSI are strong or weak. The hemodynamic analysis based on real geometry can provide surgeons with more reliable information about the effect of blood flow.

• Bulletin of the Korean Mathematical Society
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• v.59 no.2
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• pp.345-350
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• 2022

In this work, we confirm a weak version of a conjecture proposed by Hong Wang. The ideal of the work comes from the tree packing conjecture made by Gyárfás and Lehel. Bollobás confirms the tree packing conjecture for many small tree, who showed that one can pack T₁, T₂, …, $T_{n/\sqrt{2}}$ into Kn and that a better bound would follow from a famous conjecture of Erdős. In a similar direction, Hobbs, Bourgeois and Kasiraj made the following conjecture: Any sequence of trees T₁, T₂, …, T_n, with T_i having order i, can be packed into K_n-1,[n/2]. Further Hobbs, Bourgeois and Kasiraj [3] proved that any two trees can be packed into a complete bipartite graph K_n-1,[n/2]. Motivated by the result, Hong Wang propose the conjecture: For each k-partite tree T(𝕏) of order n, there is a restrained packing of two copies of T(𝕏) into a complete k-partite graph B_n+m(𝕐), where $m={\lfloor}{\frac{k}{2}}{\rfloor}$. Hong Wong [4] confirmed this conjecture for k = 2. In this paper, we prove a weak version of this conjecture.

• Journal of the Korean Society of Fashion and Beauty
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• v.5 no.1 s.12
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• pp.78-86
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• 2007

One of the latest social trends is to reappear old things under the banner of the revival. It is easily found in the fashion industry because Fashion is not divided into the past, the present and the future thing but coexisting through all ages. The purpose of this study was to pursue the healthy and characteristic beauty of the modem people by understanding the beauty culture of the ancient. The Middle ages were mainly classified into Byzantine, Romanesque and Gothic by historical and cultural factors. In the Byzantine age, the clothing with rich silhouette was worn by the influence of the abstemious religion and it didn't express a specific proportion of human body. The people covered their hair with turbans and veils for the period. The Romanesque era was affected by the religious idealism and the Greek-Roman culture. The ideal proportion of human body could be 8 heads high and the clothes expressing natural silhouette of human body came out. Depending on the feel of the flowing texture, long-braided hair was typical in that time, and also wearing kinds of head dress as personal ornaments was characteristic in the age. In the period of Gothic, the long and weak human body was emphasized. The ideal proportion of human body could be figured with 8.5 heads high and it was expressed with the form of artificial and vertical silhouette such like tight-fitting upper garments, gathered skirts and long hats.

• Journal of the Korean Mathematical Society
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• v.50 no.3
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• pp.557-578
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• 2013

For an ideal $\mathcal{I}$ of a preadditive category $\mathcal{A}$, we study when the canonical functor $\mathcal{C}:\mathcal{A}{\rightarrow}\mathcal{A}/\mathcal{I}$ is local. We prove that there exists a largest full subcategory $\mathcal{C}$ of $\mathcal{A}$, for which the canonical functor $\mathcal{C}:\mathcal{C}{\rightarrow}\mathcal{C}/\mathcal{I}$ is local. Under this condition, the functor $\mathcal{C}$, turns out to be a weak equivalence between $\mathcal{C}$, and $\mathcal{C}/\mathcal{I}$. If $\mathcal{A}$ is additive (with splitting idempotents), then $\mathcal{C}$ is additive (with splitting idempotents). The category $\mathcal{C}$ is ample in several cases, such as the case when $\mathcal{A}$=Mod-R and $\mathcal{I}$ is the ideal ${\Delta}$ of all morphisms with essential kernel. In this case, the category $\mathcal{C}$ contains, for instance, the full subcategory $\mathcal{F}$ of Mod-R whose objects are all the continuous modules. The advantage in passing from the category $\mathcal{F}$ to the category $\mathcal{F}/\mathcal{I}$ lies in the fact that, although the two categories $\mathcal{F}$ and $\mathcal{F}/\mathcal{I}$ are weakly equivalent, every endomorphism has a kernel and a cokernel in $\mathcal{F}/{\Delta}$, which is not true in $\mathcal{F}$. In the final section, we extend our theory from the case of one ideal$\mathcal{I}$ to the case of $n$ ideals $\mathcal{I}_$, ${\ldots}$, $\mathca{l}_n$.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.36 no.6
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• pp.239-246
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• 2014

Many kinds of membrane have been used for the guided bone regeneration (GBR) technique. However, most membranes do not fulfill all requirements for the ideal membrane for the GBR technique. Among them, collagen membrane has been most widely used. However, its high price and weak tensile strength in wet condition are limitations for wide clinical application. Synthetic polymers have also been used for the GBR technique. Recently, silk based membrane has been considered as a membrane for the GBR technique. Despite many promising preclinical data for use of a silk membrane, clinical data regarding the silk membrane has been limited. However, silk based material has been used clinically as vessel-tie material and an electrospun silk membrane was applied successfully to patients. No adverse effect related to the silk suture has been reported. Considering that silk membrane can be provided to patients at a cheap price, its clinical application should be encouraged.

• The Journal of the Korean dental association
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• v.10 no.12
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• pp.809-812
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• 1972

This present paper is concerned with four unit fixed bridge construction by one piece casting technique in the case of missing of upper left second premolar and first molar. The authors had good clinical results with following advantages. 1. The complete bridge can be delivered to the patient for two appointments. 2. The laboratory procedures for solder joint are not necessary. 3. A one piece casting can be properly shaped without weak joints. 4. The casting can be heat-treated to insure an ideal molecular structure. 5. Porcelain veneers can be applied without weakening or melting solder joints.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 2001.11a
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• pp.117-120
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• 2001

본 논문에서는 약한 키를 가지는 대화식 영지식 증명을 이용한 인증 프로토콜의 안전성을 강화하는 방법을 제시한다. 일반적으로 대화식 영지식 증명을 이용한 인증 프로토콜은 충분히 길고 랜덤한 비밀키를 가정하고 그 비밀키에 대한 영지식 증명을 수행하게 된다. 하지만 때에 따라서 충분히 길지 않거나 랜덤하지 않은 비밀키가 선택될 수 있다. 즉, 좋지 않은 난수 발생기를 써야 하는 경우, 또는 패스워드처럼 의도적으로 약한 키를 사용하는 경우가 생기며, 대화식 영지식 증명은 이에 적합하지 않다고 알려져 있다. 본 논문에서는 비밀 동전 던지기(Secret Coin Tossing)라는 개념을 제시해서, 일반적인 영지식 증명을 이용한 인증 프로토콜을 약한 키를 가지는 영지식 증명 기반 인증 프로토콜로 쉽게 변환할 수 있는 프레임웍을 제안한다. 또한, 이 프레임웍을 이용해서 설계된 인증 프로토콜이 ideal cipher model에서 안전함을 보인다.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1997.10a
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• pp.194-197
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• 1997

The texture of a 0.25mm dia high-carbon(0.73%) steel wire made by drawing the patented and brass coated 1.4mm wire through 22 dies with a die-angle of 12$^{\circ}$has been measured. The ideal fiber texture was obtained in the center layer, while the circular texture and the near fiber texture having {111}<110> and weak {112}<110> components were obtained in the intermediate and surface layers, respectively. The circular texture was approximated by {110}<110> plus {110}<114>. The texture could be predicted by the Taylor-Bishop-Hill theory coupled with FEM for deformation.

• Kyungpook Mathematical Journal
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• v.51 no.1
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• pp.1-10
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• 2011

Let (R, T) be a normal pair of commutative rings (i.e., R ${\subseteq}$ T is a unita extension of commutative rings, not necessarily integral domains, such that S is integrally closed in T for each ring S such that R ${\subseteq}$ S ${\subseteq}$ T) such that the total quotient ring of R is a von Neumann regular ring. Let P be one of the following ring-theoretic properties: going-down ring, extensionally going-down (EGD) ring, locally divided ring. Then R has P if and only if T has P. An example shows that the "if" part of the assertion fails if P is taken to be the "divided domain" property.