• The Transactions of the Korea Information Processing Society
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• v.2 no.3
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• pp.390-396
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• 1995

One of the advantages of computer graphics is that it enables to view an object on different viewpoints and different angles. Therefore, a computer graphics system should be able to rotate an arbitrary object by an arbitrary angle about an arbitrary axis. This is usually done by rotating vertices that represent an object and connecting them. Hence an image may have many vertices, it is important to be able to rotate each of them quickly. Therefore, this paper is interested in a rotation matrix computation method that consists of the smallest number of computational steps. This pater proposes an algorithm that computes rotation matrix to rotate a 3 dimensional image about an arbitrary axis quickly.

• Journal of the Chungcheong Mathematical Society
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• v.25 no.1
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• pp.65-72
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• 2012

Let T > 0 be given. Let $(C[0,T],m_{\varphi})$ be the analogue of Wiener measure space, associated with the Borel proba-bility measure ${\varphi}$ on ${\mathbb{R}}$, let $(L_{2}[0,T],\tilde{\omega})$ be the centered Gaussian measure space with the correlation operator $(-\frac{d^{2}}{dx^{2}})^{-1}$ and ${\el}_2,\;\tilde{m}$ be the abstract Wiener measure space. Let U be the space of all sequence $<c_{n}>$ in ${\el}_{2}$ such that the limit $lim_{{m}{\rightarrow}\infty}\;\frac{1}{m+1}\;\sum{^{m}}{_{n=0}}\;\sum_{k=0}^{n}\;c_{k}\;cos\;\frac{k{\pi}t}{T}$ converges uniformly on [0,T] and give a set function m such that for any Borel subset G of $\el_2$, $m(\mathcal{U}\cap\;P_{0}^{-1}\;o\;P_{0}(G))\;=\tilde{m}(P_{0}^{-1}\;o\;P_{0}(G))$. The goal of this note is to study the relationship among the measures $m_{\varphi},\;\tilde{\omega},\;\tilde{m}$ and $m$.

• Steel and Composite Structures
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• v.2 no.2
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• pp.147-160
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• 2002

This paper summarises results of the research performed at the Department of Steel Structures and Structural Mechanics from the "Politehnica" University of Timisoara, Romania, in order to evaluate the performance of beam-to-column extended end plate connections for steel and composite joints. It comprises laboratory tests on steel and composite joints, and numerical modelling of joints, based on tests. Tested joints are double-sided, with structural elements realised of welded steel sections. The columns are of cruciform cross-section, while the beams are of I section. Both monotonic and cyclic loading, symmetrically and antisymmetrically, has been applied. On the basis of tested joints, a refined computer model has been calibrated using a special connection element of the computer code DRAIN 2DX. In this way, a static/dynamic structural analysis of framed structures with real characteristics of the beam to column joints is possible.

• Journal of Pharmaceutical Investigation
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• v.18 no.4
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• pp.209-215
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• 1988

The three-dimensional structures of piroxicam crystallized from two different solvents, toluene and toluene/hexane mixture respectively, are proved identical: $C_{15}H_{13}N_3O_4S,\;M\;=\;331.35$, monoclinic, a = 7.128(1), b = 15.146(2), c = 13.956(2) ${\AA},\;{\beta}=\;97.33(1)^{\circ},\;V\;=\;1494.37{\AA}^{3},\;Dx\;=\;1.472\;g/cm^{3},\;Z\;=\;4,\;space\;group\;P2_{1}/c,\;Mo\;K{\alpha}(\lambda=\;0.71073\;{\AA})$, F(000) = 688, T = 295 K, R = 0.0611 for 1993 unique observed reflections. The thiazine ring exhibits a half chair conformation. An amide group is involved in an intramolecular hydrogen bond to the hydroxy group, O(17)-H(17)${\cdots}O(15){\AA}$. The molecule is planar within 2 ${\AA}$ with the interplanar angle $127.9(4)^{\circ}$ between pyridine and benzene rings. A molecular chain parallel to [011] is formed by two intermolecular hydrogen bonds N(16)-H(6)${\cdots}O(11)$ and C(6)-H(6)${\cdots}O(11)$, and the molecular chains are held together by van der Waals forces.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.150-153
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• 2004

본 논문에서는 780 nm 고출력 레이저 다이오드의 신뢰성을 향상시키기 위하여 DLTS(deep level transient spectroscopy)을 이용하여 MOCVD(metalorganic chemical vapor deposition) 성장 조건 변화에 따른 $Al_{0.48}Ga_{0.52}As$와 $Al_{0.1}Ga_{0.9}As$ 물질에서의 깊은준위(deep level)의 거동을 조사하였다. DLTS 측정결과, MOCVD로 성장된 막에서만 나타나는 결함(defect)으로 추정되는 trap A(0.3 eV), DX center로 알려진 trap B, 갈륨(Ga) vacancy와 산소(O2) 원자의 복합체(complex)에 의한 결함인 trap D(0.6 eV) 및 EL2 라고 불리우는 trap E(0.9 eV)의 네 가지 깊은준위들이 관측되었고, 성장 조건의 변화에 따라 깊은 준위들의 농도가 감소하는 것을 관측함으로써 최적 성장 조건을 찾을 수 있었다.

• Journal of the Korean Statistical Society
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• v.32 no.3
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• pp.311-311
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• 2003

This paper contains the following errors. 1. "$I_{\{x>D\}}{\lambda}dt_{p0}(t)s(x)$" should be added to the right hand side of (2.3). 2. "$I_{\{x>D\}}{\lambda}_{p0}(t)s(x)$" should be added to the right hand side of (2.6). 3. "$I_{\{x>D\}}{\lambda}_{p0}s(x)$" should be added to the right hand side of (2.9). 4. In Theorem 2.3 and its proof, "${\lambda}{\int}_{0}^{D}f(y)s(x-y)dy$" appears three times (including one in (2.20)). To each of these, "${\lambda}_{po}s(x)$" should be added. 5. In Remark 2.5, "${\lambda}dt_{p0}/s(x)dx" should be added to "${\int}_{0}^{D}{\lambda}dt\;s(x-y)dxf(y)dy$". As a result of these corrections, a simpler proof of Theorem 2.3 becomes available. Substituting (2.18), (2.21), (2.22) into the left hand side of (2.20) and comparing the result with (2.10), we have the right hand side of (2.20).

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.7 no.3
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• pp.198-204
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• 2007

In mobile robotics, ultrasonic sensors became standard devices for collision avoiding. Moreover, their applicability for map building and navigation has exploited in recent years. In this paper, as the preliminary step for developing a multi-purpose autonomous carrier mobile robot to transport trolleys or heavy goods and serve as robotic nursing assistant in hospital wards. The aim of this paper is to present the use of multi-sensor data fusion such as ultrasonic sensor, IR sensor for mobile robot to navigate, and presents an experimental mobile robot designed to operate autonomously within both indoor and outdoor environments. The global map building based on multi-sensor data fusion is applied for recognition an obstacle free path from a starting position to a known goal region, and simultaneously build a map of straight line segment geometric primitives based on the application of the Hough transform from the actual and noisy sonar data. We will give an explanation for the robot system architecture designed and implemented in this study and a short review of existing techniques, Hough transform, since there exist several recent thorough books and review paper on this paper. Experimental results with a real Pioneer DX2 mobile robot will demonstrate the effectiveness of the discussed methods.

• Proceedings of the Korea Information Processing Society Conference
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• 2012.04a
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• pp.730-733
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• 2012

소프트웨어는 대부분 바이너리 형태로 배포되기 때문에 역공학 분석이 쉽지 않다. 그러나 안드로이드는 자바를 기반으로 한다. 즉, 자바 언어로 프로그래밍하고 생성된 클래스 파일을 dx라는 도구를 사용하여 안드로이드용 달빅(Dalvik) 코드로 변환한다. 따라서 안드로이드 역시 자바의 취약점을 가지고 있고, 자바용으로 개발된 역공학 도구에 의해서 쉽게 분석될 수 있다. 한편으로 자바 프로그램의 저작권을 보호하고 핵심 알고리즘이 노출되지 않도록 다양한 난독화 도구들이 개발되었다. 그 중에서 안드로이드 SDK에 포함되어 함께 배포되고 있기 때문에 널리 사용되고 있는 프로가드(Proguard)에 대해서 대표적인 기능 및 사용법, 프로가드로 난독화된 코드가 원본과 비교하여 어떻게 변경되었는지 평가한다. 그리고 프로가드가 가지고 있는 한계를 알아보고, 이것을 극복할 수 있는 방법을 모색한다.

• Journal of the Korean Mathematical Society
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• v.58 no.5
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• pp.1181-1209
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• 2021

In the present paper, we are concerned with the existence of ground state sign-changing solutions for the following Schrödinger-Poisson-Kirchhoff system $$\;\{\begin{array}{lll}-(1+b{\normalsize\displaystyle\smashmargin{2}{\int\nolimits_{{\mathbb{R}}^3}}}{\mid}{\nabla}u{\mid}^2dx){\Delta}u+V(x)u+k(x){\phi}u={\lambda}f(x)u+{\mid}u{\mid}^4u,&&\text{in }{\mathbb{R}}^3,\\-{\Delta}{\phi}=k(x)u^2,&&\text{in }{\mathbb{R}}^3,\end{array}$$ where b > 0, V (x), k(x) and f(x) are positive continuous smooth functions; 0 < λ < λ₁ and λ₁ is the first eigenvalue of the problem -∆u + V(x)u = λf(x)u in H. With the help of the constraint variational method, we obtain that the Schrödinger-Poisson-Kirchhoff type system possesses at least one ground state sign-changing solution for all b > 0 and 0 < λ < λ₁. Moreover, we prove that its energy is strictly larger than twice that of the ground state solutions of Nehari type.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.32 no.3
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• pp.196-200
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• 2019

In this study, photoluminescence (PL) analysis was performed to evaluate the optical properties of commercial ZnO substrates. Particular attention was paid to the bound exciton (BX) luminescence, which is usually the strongest emission intensity of commercial substrates. At 15 K, PL analysis revealed that the BX peak due to donor-type impurities (donor-bound-exciton; DX) dominated, while two-electron satellite (TES) emission, donor-accepter pair (DAP) emission, and LO-phonon replica emission were also observed. The impurity concentration of the ZnO substrate was determined to be $10^{15}$ to $10^{16}/cm^3$ by examination of the temperature variation of DAP, while the half width and intensity change of the luminescence revealed that the temperature change of BX can be interpreted almost the same as the analysis of free-exciton emission.