• Convergence Security Journal
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• v.2 no.1
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• pp.35-47
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• 2002

In this paper, we will provide an overview of the motion picture watermarking techniques. We will see previously proposed algorithms such as compressed domain watermarking, non-compressed domain watermarking and algorithms for realtime applications etc. We will see test results for signature embedding in motion picture. By spread spectrum method, we embed a signature in each frames. The quality of watermarked motion picture is measured by PSNR(peak signal to noise ratio) about several strengths of watermark. In watermark detection the sign of the correlation sum is the estimated embedded signature bits. We will see different mean PSNR with visual shape of the detected signature.

• The KSFM Journal of Fluid Machinery
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• v.18 no.1
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• pp.44-50
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• 2015

Labyrinth seals are commonly used in various kinds of turbomachinery to reduce leakage flow. In the present 3D CFD analysis of see-through-type labyrinth air seal, the methodology of determining leakage and rotordynamic coefficients is suggested with the relative coordinate system for steady-state simulation. The leakage flow and rotordynamic forces predicted by using different solvers and turbulent models of FLUENT are compared with the results of the existing bulk-flow analysis code LABYSEAL.FOR and experiment. The present CFD result of direct stiffness(K) shows only improvement in prediction. The results of leakage and rotordynamic coefficients as well as computing time are sensitive against the used solver and turbulent model.

• Transactions on Electrical and Electronic Materials
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• v.17 no.1
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• pp.7-12
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• 2016

This paper proposes a metal contact RF MEMS switch which utilizes a see-saw mechanism to acquire a switching action. The switch was built on a quartz substrate and involves vertical deflection of the beam under an applied actuation voltage of 5.46 volts over a signal line. The see-saw mechanism relieves much of the operation voltage required to actuate the switch. The switch has a stiff beam eliminating any stray mechanical forces. The switch has an excellent isolation of −90.9 dB (compared to − 58 dB in conventional designs ), the insertion of −0.2 dB, and a wide bandwidth of 88 GHz (compared to 40 GHz in conventional design ) making the switch suitable for wide band applications.

• Proceedings of the Korea Contents Association Conference
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• 2018.05a
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• pp.391-392
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• 2018

대학교 캠퍼스를 방문하는 최초 방문자 대부분은 넓은 부지와 많은 건물들에 의해 혼란을 겪는 경우가 많다. 건물 명칭이 표기되어 있지만 목표건물의 위치를 쉽게 파악하기는 어렵다. 목표 건물의 위치를 파악 하였더라도 건물 내부에 대한 정보를 찾기는 더욱 힘들다. 4차 산업 혁명 시대의 급속한 발전으로 다양한 신기술이 등장하는 과정에서 증강현실(Augmented Reality) 기술이 대두되고 있다. 본 논문에서는 증강현실 기술을 이용하여 조선대학교의 건물 이름과 그 건물에 대한 정보를 제공하는 안내시스템 "See-Chosun" 어플리케이션을 제안하기로 한다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.4
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• pp.321-326
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• 2002

Near infrared spectroscopy (NIR), is recently applied to analysis of food, and it gives non-destructive and highly reproducible results. The objectives of this study were to assay protein, lipid and starch content in Alaska pollack surimi and to investigate application in seafood. NIR spectra showed the absorbance signal at 1,510 nm, 2,050 nm, 2,170 nm and 2,180 nm for protein, and signal were increased with protein content. Standard error of equation (SEE) was 0,296 and standard error of prediction (SEP) was 0.327. In analysis of lipid in Alaska pollack surimi by NIR, near infrared spectra of lyophilized Alaska pollack surimi were scanned and the signals of absorbance from C-H functional groups in lipid were identified at 1,730 nm, 1,740 nm and 2,300 nm and these signals were risen as Increasing lipid contents of Alaska pollack surimi as samely protein. SEE and SEP were 0.319, 0,353, respectively. In starch analysis using NIR the signals of starch distinctly changed at wavelength of 1,450 nm and 1,950 nm. Collected values of SEE and SEP were 0.304 and 0.318, respectively and the range of errors was $0.0186\~0.6470$ in starch contents.

• Journal of The Korean Astronomical Society
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• v.18 no.1
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• pp.1-13
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• 1985

We present the data of photoelectric photometric observations of BW Vul carried out for four nights during the period of $1982{\sim}1984$. The light curves with asymmetric shape show a stillstand on the ascending branch at phase of ${\phi}{\approx}0.85$ just before the maximum light, and also the ampitude and shape of light curves are changed from night to night. Using all the published data, a new ephemeris of maximum time is derived, in which the period of light variation is $P=0^d.20102977$ and its increasing rate is 2.2 see/century.

• Journal of the Korean Mathematical Society
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• v.32 no.4
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• pp.713-724
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• 1995

In 1954 Frame, Robinson and Thrall [5] gave the hook formula for the number of standard Young tableaux of a given shape. Since then many proofs for the hook formula have been given using various methods. See [9] forprobabilistic method and see [6] or [12] for combinatorial ones. Regev [10] has given asymptotic values for these numbers and Gouyou-Beauchamps [8] gave exact formulas for the number of standard Young tableaux having n cells and at most k rows in the cases k = 4 and k = 5.

• Bulletin of the Korean Mathematical Society
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• v.34 no.2
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• pp.211-223
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• 1997

Lehmann [13] introduced the concept of positive(negative) dependence together with some other dependence concepts. Since then, a great numerous multivariate inequalities have been obtained. For a references of available results, see Karlin and Rinott [12], Ebrahimi and Ghosh [8] and Sampson [14]. Whereas a number of dependence notions exist for multivariate processes (see Friday [10]), recently, Ebrahimi [7] introduced some new dependence concepts of the hitting times of stochastic processes.

• Bulletin of the Korean Mathematical Society
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• v.34 no.2
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• pp.185-191
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• 1997

The notions of implicative semigroup and ordered filter were introduced by M. W. Chan and K. pp. Shum [3]. The first is a generalization of implicative semilattice (see W. C. Nemitz [6] and T. S. Blyth [2]) and has a close relation with the implication in mathematical logic and set theoretic difference (see G. Birkhoff [1] and H. B. Curry [4]). For the general development of implicative semilattice theory the ordered filters play an important role, which is shown by W. C. Nemitz [6].

• Bulletin of the Korean Mathematical Society
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• v.25 no.2
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• pp.243-246
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• 1988

Let M(z)=exp (-1+z/1-z) be the unit singular inner function. See [1] or [2] for the basic facts about inner functions. We define the iterations of M9z) as (Fig.) Since the composition M$_{2}$(z)=M.M(z) is known (see [5] for example) to be singular inner function it has the "cannonical" representation (Fig.) where .mu. is a finite, positive singular Borel measure on the unit circle T. In section 2, we have explicit cannonical representation of M$_{2}$(z) by determining the singular measure .mu. In section 3 we show that (Fig.) These facts might have been known but could not be found in the literature.iterature.