• Journal of the Korean Mathematical Society
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• v.45 no.4
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• pp.1007-1025
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• 2008

We will describe a way to construct Ford domains of cusped hyperbolic 3-manifolds on maximal cusp diagrams and compute fundamental groups using face pairing maps as generators and Cannon-Floyd-Parry's edge cycles as relations. We also describe explicitly a cutting and pasting alteration to reduce the number of faces on the bottom region of Ford domains. We expect that our analysis of Ford domains will be useful on other future research.

• Fire Science and Engineering
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• v.10 no.4
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• pp.37-42
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• 1996

The "Intelligent Fire detecting and Extinguishing System" is an up-to-date fire protection system for modern high-rise buildings, international airports, enormous industrial facilities, dome stadiums such as specific areas in which the application of our local fire protection regulation could not be satisfied. The state-of-the art initiating devices communicated with sophisticated network control panels enable peoples to get reliable and powerful suppressions using water or gas, providing absolute protection. The Intelligent Water Cannon System, the Low Pressure $CO_2$ System and the MXL Networking Fire Alarm System introduced in this paper accomplish the dynamic protection for the special hazards.

• Bulletin of the Korean Mathematical Society
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• v.47 no.6
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• pp.1297-1310
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• 2010

We construct a family of 3-balls using cones which represent closed orientable 3-manifolds and study twisted face-pairing construction due to Cannon, Floyd and Parry to understand the structure of such manifolds. Moreover, we prove that those manifolds are hyperbolic.

• 한국전산유체공학회:학술대회논문집
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• 2010.05a
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• pp.581-583
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• 2010

The report summarizes research activities in the Multiscale Energy System Laboratory at Sogang University during September 2009 and February 2010. They are mostly about molecular dynamics simulation of osmotic flows at nanoscale.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2003.07b
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• pp.21-35
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• 2003

현대인이 섭취하고 있는 식품 중에서 계란의 콜레스테롤처럼 많은 연구자의 관심을 끌었던 성분도 많지 않을 것이다 콜레스테롤 섭취와 심장혈관계 질환과의 연관성에 대한 우려는 계란이 영양적으로 매우 우수한 식품임에도 불구하고 그 소비에 막대한 지장을 주고 있다. 전문가들이 하루에 섭취하는 콜레스테롤 양을 300 mg 이하로 권장하기 때문에 약 200~250 mg 의 콜레스테롤이 들어있는 계란의 섭취가 제한되고 있는 것이다 (Brown. 1990. Cannon. 1990). (중략)

• Journal for History of Mathematics
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• v.16 no.2
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• pp.23-34
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• 2003

In this paper, we consider relationship between the mathematics and the fine arts. The former is one of the advanced sciences, the latter is one of the arts. But there is correlation between the mathematics and the arts. Here, we concern with the ancient greek mathematics, Euclidean geometry and the ancient greek arts. The ancient greek arts is classified with Geometric Style, Archaic Style, Classical Style and Hellenistic Style. The Geometric Style, Classical Style and Hellenistic Style are very effected by Euclidean geometry. Because the greek artists as keep the geometric proportion as the Euclidean's 5th postulates. The artist's cannon in just golden ratio 1:(1＋$\sqrt{5}$)/2.

• Journal for History of Mathematics
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• v.16 no.4
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• pp.59-68
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• 2003

Mathematics and arts are reflection of the spirit of the ages, since they have human inner parallel vision. Therefore, in ancient Greek ages, the artists' cannon was actually geometric ratio, golden section. However, in middle ages, the Euclidean Geometry was disappeared according to the Monastic Mathematics, then the art was divided two categories, one was holy Christian arts and the other was secular arts. In this research, we take notice of Renaissance Painting and Perspective Geometry, since Perspective Geometry was influenced by Renaissance notorious painter, Massccio, Leonardo and Raphael, etc. They drew and painted works by mathematical principles, at last, reformed the paradigm of arts. If we can say Euclidean Geometry is tactile geometry, the Perspective Geometry can be called by visual geometry.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2001.04a
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• pp.489-494
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• 2001

This paper deals with a dynamic modeling of artillery system loaded by gun charge explosion during firing condition. Geometric and elastic gun data are used to modify a projectile interaction model. The maximum impact force on gun barrel was 15,000 N and the gun barrel moved about 1.3 m. A cannon bal] was presented to travel in the flexible gun, the traveling distance was about 23,000 m, and the angular velocity was about 10rad/sec. The artillery dynamic system using the multi-body dynamics enables us to obtain the data for the fatigue analysis.

• Bulletin of the Korean Chemical Society
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• v.6 no.2
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• pp.115-118
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• 1985

The oxidation of hydrazobenzene by oxygen in methanol solution is catalysed by Co(3MeOsalen) which is a synthetic oxygen carrier. The products are trans-azobenzene and water. The rate of the reaction has been studied spectrophotometrically and the rate law established. A mechanism involving a ternary complex of catalyst, hydrazobenzene and oxygen has been proposed.

• Journal of The Korean Astronomical Society
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• v.28 no.2
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• pp.153-167
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• 1995

More than 22,300 stars in NGC 6752 were measured over the region of 5' < r < 23' in B and V AAT plates. The most of these are main sequence(MS) stars and about 130 blue horizontal branch(BHB) stars were detected. The C-M diagram of all measured stars shows gaps appearing at $V{\approx}15.^{m}2$ and $16.^{m}2$ along the red giant branch(RGB) and their appearance shown by Lee & Cannon(1980) is found to be independent of measured region. The bimodal distribution of BHB stars is confirmed again and a wide gap shown by Lee & Cannon(1980) at $V{\approx}16^m$ is clearly seen for stars in the outer part (8' < r < 13') in the cluster. It is noted, however, that this gap is occupied by about a dozen of BHB staIs located in the inner region (5' < r < 8'). The number ratio of bright BHB star (V < $15^m$) to faint BHB stars (V > $15^m$) decreases with increasing radial distance from the cluster center. Three faintest BHB stars were found, and two stars ($V{\approx}18.^{m}5$) of there are located in the inner region of $r{\approx}6'$ and the other faintest one ($V{\approx}19.^{m}3$) located in the outer part of $r{\approx}13'$. Also a bluest star of (B - V) $\approx$ -0.5 at $V{\approx}17.^{m}2$ is found but it is located at the outer part of $r{\approx}13'$ in NE region. Therefore, the membership of the faintest BHB star and bluest star is suspected. The luminosity function(LF) and mass function(MF) for NGC 6752 were derived for MS stars. The LF for stars of $M_v\;<\;6^m$ in the outer part of r > 8' shows a consistency with that derived by Penny & Dickens(1986).