• The Korean Journal of Mycology
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• v.26 no.2 s.85
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• pp.211-229
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• 1998

To study the species diversity of the genus Boletellus in Korea, 56 specimens were collected from 1982 to 1996 at 20 locations including Odaesan. Collected specimens were observed and seven species among them were identified and described by observing macroscopic and microscopic characters, two of which were confirmed new to Korea: Boletellus chrysenteroides (Snell) Snell. Boletellus fallax Corner. Seven species were described here: Boletellus chrysenteroides (Snell) Snell, B. elatus Nagasawa, B. emodensis (Berk.) Singer, B. fallax Corner, B. obscurecoccineus $(V{\"{o}}hn)$ Singer, B. russellii (Frost) Gilbert, B. shichianus (Teng & Ling) Teng.

• Proceedings of the Korean Society of Computer Information Conference
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• 2024.01a
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• pp.403-406
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• 2024

본 논문에서는 비눗방울에 나타나는 반사와 굴절 효과를 상용 게임엔진인 유니티 쉐이더(Unity shader)를 사용하여 구현하고 다양한 배경에서 합성할 수 있는 효율적인 프레임워크를 제안한다. 본 논문에서 제안하는 방법은 계산량이 큰 유체 시뮬레이션을 이용하지 않고, 스넬(Snell)의 법칙을 이용하여 박막 내부의 굴절 벡터를 계산하고, 막 표면의 표현을 위해 다양한 텍스처(Texture)를 적용하였으며, vertex의 조정을 통해 비눗방울 자체의 움직임을 나타낼 수 있다. 결과적으로 실시간으로 높은 품질의 비눗방울을 표현할 수 있기 때문에 게임뿐만 아니라 가상현실 및 다양한 실시간 애플리케이션에 활용될 수 있다.

• Journal of applied mathematics & informatics
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• v.9 no.2
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• pp.745-751
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• 2002

In this paper, we Shall find the unique rational price associated with the exchange option. Also, we find the decomposition of Snell envelope and value function of the American exchange option.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.19 no.2
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• pp.170-178
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• 2007

Most of parabolic approximation models employ a relatively limited open boundary condition in which there is no depth variation in the longshore direction outside of the computation domain so that Snell's law may be presumed to hold. Existing Kirby's condition belongs to this category and in the paper both modified Kirby's method and Dirichlet boundary condition are presented in detail and numerical results of three methods were shown. Judging from computation to wave propagations over a circular shoal in a constant depth, the method based on present Dirichlet boundary condition with fictitious numerical adjusting regions in both sides of the computation domain gives the least distorted amplitude ratio distribution.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2005.11a
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• pp.422-425
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• 2005

In an transversely isotropic composite laminates, the velocities, the particle directions and the amplitudes of reflected and transmitted waves were obtained using the equation of motion, the constitutive equation, and the displacement equation expressed by wave number and frequency Eigenvalue problem involving a velocity was solved by Snell's law. Finally, the results were confirmed by T300 Carbon fiber/5208 Epoxy materials. This approach could be applied to the detection of flaws in a transversely isotropic composite laminates by the water immersion C-scan procedure.

• Journal of the Korean Society of Propulsion Engineers
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• v.10 no.2
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• pp.62-69
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• 2006

In transversely isotropic composite laminates, the velocities, the particle directions and the amplitudes of reflected and transmitted waves were obtained using the equation of motion, the constitutive equation, and the displacement equation expressed by wave number and frequency. Eigenvalue problem involving a velocity was solved by Snell's law. Finally, the results were confirmed by 7300 Carbon fiber/5208 Epoxy materials. This approach could be applied to the detection of flaws in transversely isotropic composite laminates by the water immersion C-scan procedure.

• Journal of applied mathematics & informatics
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• v.28 no.5_6
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• pp.1305-1314
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• 2010

In this paper, we deal with a class of one-dimensional reflected backward stochastic differential equations driven by a Brownian motion and the martingales of Teugels associated with an independent L$\acute{e}$vy process having a stochastic Lipschitz coefficient. We derive the existence and uniqueness of solutions for these equations via Snell envelope and the fixed point theorem.

• Journal for History of Mathematics
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• v.19 no.1
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• pp.65-78
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• 2006

The law of refraction, which is called Snell's law in physics, has a significant meaning in mathematics history. After Snell empirically discovered the refraction law $\frac{v_1}{sin{\theta}_1}=\frac{v_2}{sin{\theta}_2$ through countless observations, many mathematicians endeavored to deduce it from the least time principle, and the need to surmount these difficulties was one of the driving forces behind the early development of calculus by Leibniz. Fermat solved it far advance of others by inventing a method that eventually led to the differential calculus. Historically, mathematics has developed in close connection with physics. Physics needs mathematics as an auxiliary discipline, but physics can also belong to the lived-through reality from which mathematics is provided with subject matters and suggestions. The refraction law is a suggestive example of interrelations between mathematical and physical theories. Freudenthal said that a purpose of mathematics education is to learn how to apply mathematics as well as to learn ready-made mathematics. I think that the refraction law could be a relevant content for this purpose. It is pedagogically sound to start in high school with a quasi-empirical approach to refraction. In college, mathematics and physics majors can study diverse mathematical proof including Fermat's original method in the context of discussing the phenomenon of refraction of light. This would be a ideal environment for such pursuit.

• Computers and Concrete
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• v.12 no.3
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• pp.351-375
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• 2013

Post-punching resistance of a flat slab can help redistribute the gravity loads and resist progressive collapse of a structure following initial damage. One important difficulty with accounting for the post-punching strength of a slab is the discontinuity that develops following punching shear. A numerical simulation technique is proposed here to model and evaluate post-punching resistance of flat slabs. It is demonstrated that the simulation results of punching shear and post-punching response of the model of a slab on a single column are in good agreement with corresponding experimental data. It is also shown that progressive collapse due to a column removal (explosion) can lead to punching failure over an adjacent column. Such failure can propagate throughout the structure leading to the progressive collapse of the structure. Through post-punching modeling of the slab and accounting for the associated discontinuity, it is also demonstrated that the presence of an adequate amount of integrity reinforcement can provide an alternative load path and help resist progressive collapse.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.11a
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• pp.113-115
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• 2006

Consulting Stout & Snell's paper[1], design approaches for the pressurization system for a launch vehicle are introduced. We have outlined the typical system requirements and a dynamic model of the pressurization system. A brief summary on the control loop design for multiple on-off valve control systems has been also presented.