• 대한수학회보
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• 제60권4호
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• pp.863-872
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• 2023

Let n ⩾ 2 be an integer, we denote the smallest integer b such that gcd {(ⁿ_k) : b < k < n - b} > 1 as b(n). For any prime p, we denote the highest exponent α such that p^α | n as v_p(n). In this paper, we partially answer a question asked by Hong in 2016. For a composite number n and a prime number p with p | n, let n = a_mp^m + r, 0 ⩽ r < p^m, 0 < a_m < p. Then we have $$v_p\(\text{gcd}\{\(n\\k\)\;:\;b(n)1\}\)=\{\array{1,&&a_m=1\text{ and }r=b(n),\\0,&&\text{otherwise.}}$$

• 호남수학학술지
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• 제45권1호
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• pp.123-129
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• 2023

In this paper, we introduce the reverse of the operator Davis-Choi-Jensen's inequality. Our results are employed to establish a new bound for the Furuta inequality. More precisely, we prove that, if $A,\;B{\in}{\mathcal{B}}({\mathcal{H}})$ are self-adjoint operators with the spectra contained in the interval [m, M] with m < M and A ≤ B, then for any $r{\geq}{\frac{1}{t}}>1,\,t{\in}(0,\,1)$ $A^r{\leq}({\frac{M1_{\mathcal{H}}-A}{M-m}}m^{rt}+{\frac{A-m1_{\mathcal{H}}}{M-m}}M^{rt}){^{\frac{1}{t}}}{\leq}K(m,\;M,\;r)B^r,$ where K (m, M, r) is the generalized Kantorovich constant.

• 분석과학
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• 제16권6호
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• pp.443-449
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• 2003

붕산수에 대한 열중성자 (thermal neutron) 조사실험을 하나로를 이용하여 다음과 같은 세가지 조건에서 수행하였다: (A) $^{10}B$ 농도 = $203.0{\mu}g/mL$, 조사시간 = 1 시간; (B) $^{10}B$ 농도 = $381.4{\mu}g/mL$, 조사시간 = 1 시간; (C) $^{10}B$ 농도 = $381.4{\mu}g/mL$, 조사시간 = 0.5 시간. 열중성자 조사 시 발생하는 핵반응 [$^{10}B(n{\cdot}{\alpha})^7Li$]으로부터 생성된 $^7Li$의 양은 불꽃 없는 원자흡수분광분석법 (flameless atomic absorption spectroscopy)으로 측정하였다. (A), (B), (C) 실험에서 측정된 $^7Li$의 농도는 각각 0.18 (이론치 = 0.23), 0.31 (이론치 = 0.44), 0.16 (이론치 = 0.22) ${\mu}g/mL$로 이 값들은 각각 이론치의 78.3, 70.5, 71.6%에 해당한다 중성자 조사 후 붕산수의 pH는 조사 전의 값에 비하여 상당히 낮은 값을 보였다. 이는 물의 방사분해물의 영향으로 붕산수가 해리도가 큰 polyborate 형태로 전이되기 때문으로 판단된다.

• 천문학회지
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• 제14권1호
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• pp.1-11
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• 1981

Photoelectric drift scans of nearby galaxies, M106, M31 and M33 have been made at diurnal rate with the 61cm Cassegrain Reflector at Sobacksan Observing Station. Luminosity profiles of M106 and M31 show the asymmetries between east and west sides of the galaxies and the near side of each galaxy exhibits a larger B-V color than the far side. B-V color distribution in the central part of MI06 shows somewhat unusual feature of a blue center with red surrounding regions, and this is an opposite trend to the ordinary color distribution of most of external galaxies. B-V color of M31 is nearly constant in the central part of the galaxy while U-B color decreases as the distance from the center increases.

• 수산해양기술연구
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• 제25권1호
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• pp.12-17
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• 1989

고등어 낚시어장에서 150Hz~200Hz의 순음과 단속순음을 수중스피커로 수중에 방성하였을 때 고등어 어군의 반응과 어선의 보조기관의 수중소음을 측정\ulcorner분석한 결과를 요약하면 다음과 같다. 1. 보조기관만을 운전하였을 때 수중소음의 중심주파수와 음압레벨은 수심 20m에서 각각 500Hz, 146.8dB이었다. 2. 주파수 150Hz와 200Hz의 순음의 음압레벨은 수심 30m, 70m, 120m에서 각각 141.0dB와 146.6dB, 120.0dB와 126.6dB, 114.3dB와 120.5dB이였다. 3. 수중음을 방성해서 5분 전후에 고등어 어군이 유집반응을 보였다. 4. 주파수 150Hz와 200Hz의 순음보다는 단속순음이 좋은 유집반응을 나타냈다

• 천문학회보
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• 제37권2호
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• pp.155.2-155.2
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• 2012

CTIO 4m 및 CTIO 1m 망원경으로 Westerlund 2의 UBVI 관측을 수행하여, CTIO 4m SDSS $u$ filter의 적색광누출 현상을 발견하였고 그 영향을 분석하였다. 적색광누출 현상은 filter의 투과함수가 설계와는 달리 장파장 영역에서 투과 존재하는 현상으로, CTIO 4m SDSS $u$ filter의 경우 B-V>1.4, V-I>2.0에서 그 영향이 나타나기 시작한다. SDSS $u$ filter의 적색광누출 현상은 별의 고유색지수와 상관없이 관측된 색지수가 클수록 영향이 크며, $B-V{\leq}1.8$, $V-I{\leq}2.8$의 범위에서는 보정이 가능하다. CTIO 1m B filter에서는 성간소광을 받지 않은 별과 성간소광을 많이 받은 별의 표준계변환 결과, $B_{CTIO1m}=B_{Standard}-0.055{\times}E(V-V)$에 해당하는 차이를 보였다. 이러한 차이는 CTIO 1m B filter의 투과함수의 단파장 쪽 날개부분이 표준 Johnson B filter에 비하여 단파장 쪽으로 많이 치우쳐있기 때문으로 보인다. 특히 Ballmer jump에 해당하는 파장인 370 nm에서 filter의 최대투과율에 비하여 32.2%에 달하는 투과율을 보이는데, 이는 Bessell B filter의 3.1%에 비하여 매우 큰 값이다. CTIO 1m 망원경의 Y4KCam CCD에서는 포화된 화소에 의한 crosstalk 뿐 아니라 포화되지 않은 화소에 의한 crosstalk 현상도 보였다. 짧은 노출을 준 영상에서는 5000 ADU 이상에서는 육안에 의한 crosstalk 확인이 가능하며, 포화되지 않은 밝은 별에 의한 crosstalk을 확인하지 않고 측광할 경우 백색왜성으로 오인할 가능성이 있으므로 측광 과정에서 좌표를 통하여 확인할 필요가 있다.

• Kyungpook Mathematical Journal
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• 제53권1호
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• pp.37-47
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• 2013

Let M and X be right R-modules. We introduce several modules relative to the class of B(M, X) and we investigate relation among these modules. In this note, we show if M is X-${\oplus}$-supplemented such that $M=M_1{\oplus}M_2$ implies $M_1$ and $M_2$ are relatively B-projective, then M is an X-H-supplemented module.

• 수산해양기술연구
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• 제31권1호
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• pp.29-44
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• 1995

A model experiment on the pair midwater trawl net applicable to 800 PS class Korean pair bottom trawlers was carried out in the special-prepared experimental thank. the tank was prepared as a reverse trapezoid shape in its vertical section by digging out flat soil. The dimension of the tank showed the 9.6 W$\times$43.0 L(m) of the upper fringe and the 4.8 W$\times$38.0 L(m) of the bottom with 3.0m in depth. The depth of water was maintained 2.7m during experiment. The model net was prepared based on the Tauti's similarity law of fishing gear in 1/30 scale considering the dimension of the experimental tank. Mouth performance of the model net during towing were determined by the photographs taken in front of the net mouth with the combinations of towing velocity, warp length and distance between paired boats. The results obtained can be summarized as follows: 1. Vertical opening of the model nets A and B was varied in the range of 0.18~0.88 m and 0.21~0.78 m (which can be converted into 5.4~26.4m and 6.3~23.4 m in the full-scale net) respectively, and was varied predominantly by towing speed. Vertical opening (H which is appendixed m for the model net. f for the full-scale net. A and B for the types of the model net) can be expressed as the function of towing velocity$V_t$as in the model net $V_t$ : m/ sec)$H_{mA}$=1.67$e^{-1.65V_t}$ $H_{mB}$=1.15$e^{-1.13V_t}$, in the full-scale net ($V_t$ : k't) $H_{fA}$=50.27$e^-0.37V_t$ $H_{fB}$=34.46$e^{-0.26Vt}$. 2. Horizontal opening of the model nets An and b was varied in the range of 1.03~1.54m and 1.04~1.55 m (which can be converted into 30.9~46.2 m and 31.2~46.5m in the full-scale net) respectively, and was varied predominantly by distance between paired boats. Horizontal opening (W, appendixes are as same as the former) an be expressed as the function of distance between paired boats $D_b$as in the model net $W_{mA}$=0.69+0.09$D_b$ $W{mB}$=0.73+0.09$D_b$, in the full-scale net $W_{fA}$=20.81+0.09$D_b$ $W_{fB}$=22.11+0.09$D_b$ 3. Net opening area of the model net A and B was varied in the range of 0.28~1.04 $m^2$ and 0.33~0.94$m^2$(which can be converted into 252~936$m^2$ and 297~846$m^2$ in the full-scale net) respectively, and was varied predominantly by towing velocity. Net opening area ($S$, appendixes are as same as the former) van be expressed as the function of towing velocity$V_t$ as in the model net $v_t$ : m/sec) $S_{Ma}$=2.01$e^{-1.54V_T}$ $S_{mA}$=1.40$e^{-1.65V_t}$, in the full-scale net ($V_t$ : k't) $S_{fA}$=1.807$e^-0.35V_t$ $S_{fA}$=1.265$e^{-0.24V_t}$. 4. Filtering volume of the model nets A and B was varied in the range of 0.32~0.55 $m^3$ and 0.37~0.55$m^3$(which can be converted into 8.640~14.850 $m^3$ and 9.990~14.850$m3$in the full~scale net) respectively, and was predominantly varied by towing speed. filtering volume of the model net-A showed the maximum at the towing speed 0.69 m/sec(3 k't in the full-scale net), compared with that of the model net B showed at 0.92 m/sec(4 k't in the full-scale net).

• 한국전자파학회논문지
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• 제11권6호
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• pp.893-899
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• 2000

본 논문에서는 0.65 $\mu$m CMOS 공정을 이용한 900MHz 대역의 저잡음 증폭기를 설계하였다. 입력 매칭은 전력소모가 가정 적고 NF도 가장 작은 인덕터 종단 정합회로를 사용하였다. 온칩 상에 바이어스 안정화를 포한시켰으며, 전원은 3V를 공급하였을 때 전력 소모는 39mW이다. 설계된 저잡음 증폭기의 특성능 900MHz 대역에서 13.2dB의 이득과 4.8dB의 Noise Figure가 측정이 되었다. 입력 반사손실으 -26dB, 츨력반사 손실은 -17dB을 얻었으며, 입력 1-dB 억압 -12dBm을 얻었다.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2015년도 추계학술대회 및 정기총회
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• pp.23-23
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• 2015

Rice blast disease caused by M. oryzae is the most devastating fungal disease in rice. During the infection process, M. oryzae secretes a large number of glycosyl hydrolase (GH) proteins into the apoplast to digest host cell wall and assist fungal ingress into host tissues. In this study, we identified a novel M. oryze arabinofuranosidase B (MoAbfB) which is secreted during fungal infection. Live-cell imaging exhibited that fluorescent labeled MoAbfB was highly accumulated in fungal invasive structures such as appressorium, tips of penetration peg, biotrophic interfacial complex (BIC), as well as invasive hyphal tip. Deletion of MoAbfB mutants extended biotrophic phase followed by enhanced disease severity, whereas, over-expression of OsMoAbfB mutant induced rapid defense responses and enhanced rice resistance to M. oryzae infection. Furthermore, exogenous treatment of MoAbfB protein showed inhibition of fungal infection via priming of defense gene expression. We later found that the extract of MoAbfB degraded rice cell wall fragments could also induce host defense activation, suggesting that not MoAbfB itself but oligosaccharides (OGs) derived from MoAbfB dissolved rice cell wall elicited rice innate immunity.