• 제목/요약/키워드: f-

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전자빔여기 XeF$(C\rightarrowA$ 엑시머 레이저의 출력특성에 대한 시뮬레이션 해석 (Simulation Anaysis on the Output Characteristics of XeF$(C\rightarrowA$ Excimer Laser Pumped by Electron-Beam)

  • 류한용;이주희
    • 한국광학회지
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    • 제6권3호
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    • pp.201-213
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    • 1995
  • 전자빔여기 XeF$(C\rightarrowA$ 엑시며 레이저의 상준위 B-와 C-상태에 대하여 충동혼합 운동과정을 포함하는 모델을 컴퓨터 시뮬레이션하여 이의 출력특성을 해석하였다 $XeF^*(B)$ 의 수밀도에 관련되는 $XeF^*(C)$의 형성에 대하여 레이저 에너지를 실험치와 비교하였다. 이 결과는 70ns[FWHM]의 전자빔(800kV, 21kA)을 사용한 대기압 매질에서 매우 좋은 일치$(28.5 mJ\pm5%)$를 보였고, $Xe/F_2/Ar=5.26/0.49/94.28%$의 최적화된 가스혼합비를 확인하였다. 또한 시뮬레이션으로 $XeF^*(C)$의 형성경로, $XeF^*(C)$의 완화경로, 청록색 파장대역의 흡수경로에 대한 $F_2$ 할로겐 도우너 및 Xe 압력의 함수관계를 조사하였다.

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The Idea and the Role of Field-Museums in Japan

  • Horie, Noriko;Tabata, Sadatoshi
    • 한국조경학회:학술대회논문집
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    • 한국조경학회 2007년도 Journal of Landscape Architecture in Asia Vol.3
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    • pp.202-207
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    • 2007
  • Recently, the number of 'field-museums(F.Ms.)' in Japan has increased. Although they are very diverse, the essential commonality is that each has a field arranged as a kind of museum. In this study, we examine the 'F.M.' mainly through documents in order to understand the concept of the F.M. and the direction of further studies. Before examining the cases of F.Ms., we explore the history of the F.M. and the role of museums in order to establish the background of the development of F.Ms. The term F.M. first appeared and evolved in 1990s. It is suggested that F.Ms. are positioned on the same lines as development of museums, and that the field of museums and the field of landscaping is beginning to overlap. Concerning the role of museums, we examined the definition of museums in terms of conventional museums and regional planning. Next, the documents of 36 cases of F.Ms. are checked regarding their types and roles. Consequently, we found that while most F.Ms. cases have both the role of conventional museums and the role of regional planning, it is difficult to say that the role has some connection with the type. It seems that F.Ms. emphasize 'education' rather than 'collection', 'pleasure' and 'research', compared with conventional museums. In addition, the role of regional planning is strongly expected. In many cases, the F.M. is expected to be a method of regional management, not merely a museum. In order to use F.Ms. for regional planning and landscaping effectively, it is desirable for F.Ms. to be defined from this viewpoint. For this purpose, it is necessary to determine the extent of F.Ms. The problem is which extent to choose, geographical unity or administrative border. Hence, further comparative research is needed clarify the association between the extent and the identity in order to establish a more effective size of F.Ms.

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The f0 distribution of Korean speakers in a spontaneous speech corpus

  • Yang, Byunggon
    • 말소리와 음성과학
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    • 제13권3호
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    • pp.31-37
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    • 2021
  • The fundamental frequency, or f0, is an important acoustic measure in the prosody of human speech. The current study examined the f0 distribution of a corpus of spontaneous speech in order to provide normative data for Korean speakers. The corpus consists of 40 speakers talking freely about their daily activities and their personal views. Praat scripts were created to collect f0 values, and a majority of obvious errors were corrected manually by watching and listening to the f0 contour on a narrow-band spectrogram. Statistical analyses of the f0 distribution were conducted using R. The results showed that the f0 values of all the Korean speakers were right-skewed, with a pointy distribution. The speakers produced spontaneous speech within a frequency range of 274 Hz (from 65 Hz to 339 Hz), excluding statistical outliers. The mode of the total f0 data was 102 Hz. The female f0 range, with a bimodal distribution, appeared wider than that of the male group. Regression analyses based on age and f0 values yielded negligible R-squared values. As the mode of an individual speaker could be predicted from the median, either the median or mode could serve as a good reference for the individual f0 range. Finally, an analysis of the continuous f0 points of intonational phrases revealed that the initial and final segments of the phrases yielded several f0 measurement errors. From these results, we conclude that an examination of a spontaneous speech corpus can provide linguists with useful measures to generalize acoustic properties of f0 variability in a language by an individual or groups. Further studies would be desirable of the use of statistical measures to secure reliable f0 values of individual speakers.

페어링 암호 연산을 위한 $F_{3^m}$에서의 효율적인 세제곱근 연산 방법 (Efficient Formulas for Cube roots in $F_{3^m}$ for Pairing Cryptography)

  • 조영인;장남수;김창한;박영호;홍석희
    • 정보보호학회논문지
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    • 제21권2호
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    • pp.3-11
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    • 2011
  • $F_{3^m}$에서의 Tate 페어링 또는 ${\eta}_T$ 페어링 알고리즘 계산을 위하여 효율적인 세제곱근 계산은 매우 중요하다. $x^{1/3}$의 다항식 표현 중 0이 아닌 계수들의 개수를 $x^{1/3}$의 헤밍웨이트라 할 때, 이 헤밍웨이트가 세제곱근 연산의 효율성을 결정하게 된다. O. Ahmadi 등은 $f(x)=x^m+ax^k+b$ (a, $b{\in}F_3$)가 $F_3[x]$의 삼항 기약다항식이라 할 때, $F_{3^m}=F_3[x]/(f)$을 생성하는 모든 삼항 기약다항식에 대하여 $x^{1/3}$의 헤밍웨이트를 계산하였다. 본 논문에서는 Shifted Polynomial Basis(SPB)가 기존의 결과보다 $x^{1/3}$의 헤밍웨이트를 낮출 수 있음을 보이며, 모듈로 감산 연산이 필요 없는 가장 적합한 SPB를 제공한다.

3차원 공간 스캔을 위한 ToF-Stereo 융합 센서 시스템 설계 (Design of ToF-Stereo Fusion Sensor System for 3D Spatial Scanning)

  • 이윤주;유선국
    • 스마트미디어저널
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    • 제12권9호
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    • pp.134-141
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    • 2023
  • 본 논문에서는 3차원 객체의 인식률을 높이고 객체 검출 품질이 보장되며, 환경에 강건한 3차원 공간 스캔용 ToF-Stereo 융합 센서 시스템을 제안한다. ToF-Stereo 센서 융합 시스템은 ToF 센서와 Stereo RGB 센서의 센싱 값을 융합하는 방식을 사용하며, 하나의 센서가 동작하지 않더라도 다른 하나의 센서를 이용하여 계속해서 객체를 검출해 나갈 수 있다. ToF 센서와 Stereo RGB 센서의 센싱 거리, 센싱 해상도, 빛 반사도 및 조도 등에 따른 품질이 달라지므로, 신뢰도 추정에 기반하여 센서의 기능을 조절할 수 있는 모듈을 두었다. ToF-Stereo 센서 융합 시스템은 ToF 센서와 Stereo RGB 센서의 센싱 값을 결합하고, 신뢰도를 추정한 후 신뢰도에 따라 센서의 기능을 조절하여 두 센싱 값을 융합하므로 3차원 공간 스캔의 품질을 향상할 수 있다.

COMPOSITION OF POLYNOMIALS OVER A FIELD

  • Choi, EunMi
    • 충청수학회지
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    • 제22권3호
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    • pp.497-506
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    • 2009
  • This work studies about the composition polynomial f(g(x)) that preserves certain properties of f(x) and g(x). We shall investigate necessary and sufficient conditions of f(x) and g(x) to be f(g(x)) is separable, solvable by radical or split completely. And we find relationship of Galois groups of f(g(x)), f(x) and of g(x).

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ON F-HARMONIC MAPS AND CONVEX FUNCTIONS

  • Kang, Tae-Ho
    • East Asian mathematical journal
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    • 제19권2호
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    • pp.165-171
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    • 2003
  • We show that any F-harmonic map from a compact manifold M to N is necessarily constant if N possesses a strictly-convex function, and prove 'Liouville type theorems' for F-harmonic maps. Finally, when the target manifold is the real line, we get a result for F-subharmonic functions.

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ON F-STRUCTURE MANIFOLD

  • Upadhyay, M.D.;Das, Lovejoy S.K.
    • Kyungpook Mathematical Journal
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    • 제18권2호
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    • pp.277-283
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    • 1978
  • The first part of this paper is devoted to the study of F-structure satisfying: $F^K+(-)^{K+1}F=0$ and $F^W+(-)^{W+1}F{\neq}0$, for 1$${\geq_-}3$$) has been considered. In the later part some structures involving Lie-derivatives. exterior and co-derivatives have been studied.

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On the Topological Stability in Dynamical Systems

  • Koo, Ki-Shik
    • 충청수학회지
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    • 제7권1호
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    • pp.199-209
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    • 1994
  • In this paper, we show that a persistent dynamical system is structurally stable with respect to $E_{\alpha}$(X) for every ${\alpha}$ > 0 if it is expansive. Also, we prove that a homeomorphism$ f:{\Omega}(f){\rightarrow}{\Omega}(f)$ has the semi-shadowing property then so does $f:\overline{C(f)}{\rightarrow}\overline{C(f)}$.

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