검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 68

        61.
        2002.12 KCI 등재 서비스 종료(열람 제한)
        We calculated dose rate using radiative transfer equations to consider radiative processes distinctly. The dose rate at Pohang(36°02'N, 129°23'E) was calculated using measured ozone and meteorological data and two-stream approximations(quadrature, Eddington, delta Eddington, PIFM(practical improved flux method), discrete ordinate, delta discrete ordinate) are used in solving equation. The purpose of this study is to determine the most compatible radiative transfer approximation for simulating the radiative and photochemical processes of atmosphere through comparision between calculated and measured values. Dose rate of the biologically effective irradiance in the region 0.28-0.32μm showed the highest value when quadrature and Eddington was used and lower value on condition that delta scaling was applied. Correlation coefficient between dose rate at surface using radiation transfer equation and measured UV-B at Pohang was 0.78, 0.79 and 0.81 when detla Eddington, PIFM and delta discrete ordinate were used. Also, in case of above approximations were used, MBE(Mean Bias Error) was within -0.3MED/30min and RMBE(Relative Mean Bias Error) was below 10% between 1200 LST and 1400 LST. Approximations which are compatible in estimating radiative process are detla Eddington, PIFM and delta discrete ordinate. Especially, in case that radiative process is considered more detail, delta discrete ordinate increased the number of stream is proper.
        64.
        2000.03 KCI 등재 서비스 종료(열람 제한)
        Choe, Hyon Sook. 2000. Focus-sensitive Question and Copy Theory. Studies in Modern Grammar 19, 27-48. In this paper, adopting a version of Chomsky`s (1971) conception of focus/presupposition (cf. also Dryer 1996), I suggest that yes-no question and wh-question refer to the information of focus and that the extraction of yes-no and wh-question operators (that are lexically inserted on a focus) is involved in yes-no and wh-questions. I also suggest that the concept of focus is both LF- and PF-related and that extraction in yes-no question and wh-question refers to PF-related focus information while yes-no and wh-question operators are lexically inserted on an LF-related focus (a focus category, here) so that only focus categories (which are not presupposed) can be questioned. Based on the above suggestion, I reinterpret the copy theory introduced in Chomsky (1993) by suggesting a notion of selective deletion under an hypothesis that the information on LF- and PF-related focus is syntactically available in terms of formal feature. The hypothesis makes it possible to suggest a copy theory that employs selective deletion but not QR, which is conceptually and theoretically better than a copy theory discussed in Chomsky (1993) and assumed in Chomsky (1995, 1998, 1999).
        65.
        1999.12 KCI 등재 서비스 종료(열람 제한)
        Effects of surface conditions (temperature and roughness) of test specimens, when measuring emissive power of far-infrared ray, have been investigated using FT-IR spectrometer. Element metal zinc (Zn) was selected in this study as representative specimen of materials consisting of simple element. The zinc specimens were heated to four temperatures, i.e., 333K, 353K, .373K, and also their surface was finished with SiC abrasive papers of 100, 220, 360, 400, 600, 800, and 1000 mesh in size. The results shows that the emissive power (W/㎡) of the far-infrared ray increases with temperature for a given roughness and its relationship may be expressed by the following equations: Yη=1.0=0.142.T-0.937 for η=1.0, and Yη=10=0.016.T-1.286 for η=10. The emissive power is also known to increase with surface roughness for a given temperature. Their relationship can be represented by the following equations: YT=313K=0.234.ln(η)+3.53, at 313K, YT=353K=0.234.ln(η)+4.02 at 353K and YT=393K=0.243.ln(η)+4.62 at 393K.
        1 2 3 4