• 제목/요약/키워드: logarithmic unit

검색결과 33건 처리시간 0.01초

곡류의 감마선 조사 검지를 위한 DEFT/APC 방법의 이용 (Detection of Gamma-Irradiated Grains by Using DEFT/APC Method)

  • 오경남;이숙영;양재승
    • 한국식품과학회지
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    • 제34권3호
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    • pp.380-384
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    • 2002
  • For the screening of gamma-irradiated grains, domestic rice, glutinous rice, barley, and wheat were irradiated with 0.1, 0.3, 0.5, 0.7, and 1.0 kGy and screened using the DEFT/APC (Direct Epifluorescent Filter Technique/Aerobic Plate Count) method. The log DEFT/APT units increased with the dose increment in all samples, whereas the log APC unit decreased gradually. For rice, barley, and wheat, unirradiated and irradiated samples with below 0.3 kGy had 2.0 or lower logarithmic units, whereas those with 0.5 kGy or higher had 2.0 or higher logarithmic units. For glutinous rice, the sample irradiated with 0.5 kGy showed 1.92 logarithmic unit and those with 0.7 kGy or higher had 2.0 or higher logarithmic units. These results suggest that if the grains show 2.0 or higher logarithmic units, they could be assumed to have been irradiated at a dose level of at least 0.5 kGy. In conclusion, grains could be easily screened through the DEFT/APC method.

WEIGHTED COMPOSITION OPERATORS FROM F(p, q, s) INTO LOGARITHMIC BLOCH SPACE

  • Ye, Shanli
    • 대한수학회지
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    • 제45권4호
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    • pp.977-991
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    • 2008
  • We characterize the boundedness and compactness of the weighted composition operator $uC_{\psi}$ from the general function space F(p, q, s) into the logarithmic Bloch space ${\beta}_L$ on the unit disk. Some necessary and sufficient conditions are given for which $uC_{\psi}$ is a bounded or a compact operator from F(p,q,s), $F_0$(p,q,s) into ${\beta}_L$, ${\beta}_L^0$ respectively.

ON THE $FEKETE-SZEG\"{O}$ PROBLEM FOR STRONGLY $\alpha$-LOGARITHMIC CLOSE-TO-CONVEX FUNCTIONS

  • Cho, Nak-Eun
    • East Asian mathematical journal
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    • 제21권2호
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    • pp.233-240
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    • 2005
  • Let $CS^{\alpha}(\beta)$ denote the class of normalized strongly $\alpha$-logarithmic close-to-convex functions of order $\beta$, defined in the open unit disk $\mathbb{U}$ by $$\|arg\{\(\frac{f(z)}{g(z)}\)^{1-\alpha}\(\frac{zf'(z)}{g(z)\)^{\alpha}\}\|\leq\frac{\pi}{2}\beta,\;(\alpha,\beta\geq0)$$ where $g{\in}S^*$ the class of normalized starlike functions. In this paper, we prove sharp $Fekete-Szeg\"{o}$ inequalities for functions $f{\in}CS^{\alpha}(\beta)$.

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Humid air 분위기로부터 대기 압력에 따른 Cr-Mo 저합금강의 고온 산화 거동 (High Temperature Oxidation Behavior of Cr-Mo Low Alloy Steel According to Atmospheric Pressures in Humid Air)

  • 권기훈;박현준;이영국;문경일
    • 열처리공학회지
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    • 제35권5호
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    • pp.246-254
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    • 2022
  • The high-temperature oxidation behavior of Cr-Mo steel AISI 4115 in air at different temperatures (600, 850, 950℃) for 120 min was studied by mass gain analysis, phase analysis (optical microscopy, electron probe micro-analysis, x-ray diffraction) and hardness measurement of each iron oxide-phase. The oxidation scales that formed on oxidation process consisted outer layer (Hematite), middle layer (Magnetite) and the inner layer (Chromite). In the case of 850 and 950℃, the oxidation mass gain per unit area of AISI 4115 steel increased according to the logarithmic rate as atmospheric pressure increased. Especially, It has been observed that with an increase in the atmospheric pressure at 600℃, the oxidation mass gain per unit area changed from a linear to logarithmic relationship.

라플라스 신호원에 대한 최소평균제곱오차 홑 양자기의 지지역에 관하여 (On the Support of Minimum Mean-Square Error Scalar Quantizers for a Laplacian Source)

  • 김성민;나상신
    • 한국통신학회논문지
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    • 제31권10C호
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    • pp.991-999
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    • 2006
  • 이 논문은 라플라스 밀도 함수에 대한 최적 흩 양자기의 지지역의 증가는 양자점의 개수와 대수적인 관계가 있음을 보여준다. 구체적으로, 분산이 1인 라플라스 밀도함수에 대해서 양자정의 개수 N이 증가할 때 최적 양자기의 경계값에 의해 결정되는 지지역과 $\frac 3{\sqrt{2}}1n\frac N 2$의 비율이 1로 수렴함을 보여준다. 또한 극한 상한값을 유도하여 최적 지지역의 로그적 증가가 그 값을 초과하지 않음을 보였다. 이 결과들로부터 이전부터 경험적으로 연구되어 온 최적 지지역의 로그 증가를 확인 할 수 있다.

THE ATOMIC DECOMPOSITION OF HARMONIC BERGMAN FUNCTIONS, DUALITIES AND TOEPLITZ OPERATORS

  • Lee, Young-Joo
    • 대한수학회보
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    • 제46권2호
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    • pp.263-279
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    • 2009
  • On the setting of the unit ball of ${\mathbb{R}}^n$, we consider a Banach space of harmonic functions motivated by the atomic decomposition in the sense of Coifman and Rochberg [5]. First we identify its dual (resp. predual) space with certain harmonic function space of (resp. vanishing) logarithmic growth. Then we describe these spaces in terms of boundedness and compactness of certain Toeplitz operators.

모바일 그래픽 응용을 위한 파이프라인 구조 특수 목적 연산회로의 하드웨어 설계 (Hardware Design of Pipelined Special Function Arithmetic Unit for Mobile Graphics Application)

  • 최병윤
    • 한국정보통신학회논문지
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    • 제17권8호
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    • pp.1891-1898
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    • 2013
  • 3차원 그래픽 API인 OpenGL과 Direct3D를 효율적으로 처리하기 위해 sine, cosine, 역수, 역제곱근, 지수 및 로그 연산을 처리하는 부동소수점 연산회로를 설계하였다. 고속 연산과 2 ulp 보다 작은 오차를 만족시키기 위해 2차 최대최소 근사 방식과 테이블 룩업 방식을 사용하였다. 설계된 회로는 65nm CMOS 표준 셀 조건에서 2.3-ns의 최대 지연시간을 갖고 있으며, 약 23,300 게이트로 구성된다. 최대 400 MFLOPS의 연산 성능과 높은 정밀도로, 설계한 연산회로는 3차원 모바일 그래픽 분야에 효율적으로 적용 가능하다.

천해용 Side Scan Sonar의 송수신 시스템 구현 및 운용에 관한 연구 (Development of a Side Scan Sonar System for Underwater Sun)

  • 오영석;이철원;강도욱;우종식
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2000년도 추계학술대회 논문집
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    • pp.222-227
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    • 2000
  • "Side scan sonar" using acoustic signal has been developed to survey cable laying, sunken bodie\ulcorner bottom and so on. It use the acoustic signals, which are emitted from two transducer arrays, to get gemetri\ulcorner target area. This system consists of transceiver board, towed body, and deck unit. The transceiver board, w\ulcorner watertight canister of the towed body, controls the transmitting and receiving of 400kHz acoustic signals from \ulcorner After receiving the scattered signals, it processes the filtering, AGF(Automatic Gain Control), TVG(Time Heterodyne. The deck unit is composed of the signal processing part, A/D converter, power supplier, and real\ulcorner And the towed body has been designed to satisfy the optimal hydrodynamic behavior during towing. The de\ulcorner theory of transceiving part and some results from field-experiments will be introduced here.

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New three-layer-type hysteretic damper system and its damping capacity

  • Kim, Hyeong Gook;Yoshitomi, Shinta;Tsuji, Masaaki;Takewaki, Izuru
    • Earthquakes and Structures
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    • 제3권6호
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    • pp.821-838
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    • 2012
  • This paper proposes a new three-layer pillar-type hysteretic damper system for residential houses. The proposed vibration control system has braces, upper and lower frames and a damper unit including hysteretic dampers. The proposed vibration control system supplements the weaknesses of the previously proposed post-tensioning vibration control system in the damping efficiency and cumbersomeness of introducing a post-tension. The structural variables employed in the damper design are the stiffness ratio ${\kappa}$, the ductility ratio ${\mu}_a$, and the ratio ${\beta}$ of the damper's shear force to the maximum resistance. The hysteretic dampers are designed so that they exhibit the targeted damping capacity at a specified response amplitude. Element tests of hysteretic dampers are carried out to examine the mechanical property and to compare its restoring-force characteristic with that of the analytical model. Analytical studies using an equivalent linearization method and time-history response analysis are performed to investigate the damping performance of the proposed vibration control system. Free vibration tests using a full-scale model are conducted in order to verify the damping capacity and reliability of the proposed vibration control system. In this paper, the damping capacity of the proposed system is estimated by the logarithmic decrement method for the response amplitudes. The accuracy of the analytical models is evaluated through the comparison of the test results with those of analytical studies.