• 한국광학회지
• /
• 제7권2호
• /
• pp.162-166
• /
• 1996

전왜재질 0.9 PMN/0.1PT에 각각 조성비율이 1%, 2%, 3%의 La이 첨가된 3종류의 재질을 광섬유에 부착하여 광섬유 전왜변환기를 제작하였다. 실험결과 La 3% 첨가된 재질의 전왜계수가 3.38kHz에서 3.87*$10^{-16}$(m/V)$^{2}$로 가장 크다는 것을 알 수 있었으며 La을 첨가함으로 해서 이력이 줄어듬을 알 수 있었다. La 3%인 재질로 구현된 광섬유 전계센서의 최소감지전계는 2.08(V/m).root.Hz였으며 가변영역 40dB 이상에 걸쳐서 선형성이 우수하였다.

• 대한원격탐사학회지
• /
• 제16권2호
• /
• pp.109-116
• /
• 2000

This study was carried out to assess the use of RADARSAT data which is C-band with HH polarization for the rice growth monitoring in Korea. Nine time-series data were taken by shallow incidence angle (standard beam mode 5 or 6) during rice growing season. And then, backscattering coefficients ($\sigma$$^{\circ}$) were extracted by calibration process for comparing with rice growth parameters such as plant height, leaf area index(LAI), and fresh and dry biomass. Field experimental data concerned with rice growth were collected 8 times for the ground truth at the study area, Tangjin, Chungnam, Korea. At the beginning of rice growth, backscattering coefficients were ranged from -l6~-l3dB when rice fields were not covered with rice canopy and flooded. At the maximum vegetative stage of rice, backscattering coefficients of the rice field were the highest ranging from -4.4dB~-3.1dB. The temporal variation of backscattering coefficient($\sigma$$^{\circ}$) in rice field was significant in this study. Backscattering coefficient ($\sigma$$^{\circ}$) of rice field was a little bit lower again after heading stage than before. This results show RADARSAT data is promising for rice monitoring.

• Bulletin of the Korean Chemical Society
• /
• 제26권12호
• /
• pp.1941-1945
• /
• 2005

To raises the possibility of designing effective inhibitors, 3D-QSAR for the inhibition of calcineurin-NFAT signaling by new N-(4-oxo-1(4H)-naphthalenylidene benzenesulfonamide derivatives as inhibitors of intracellular protein-protein interactions were studied using CoMFA and CoMSIA methodology. The three templates, N-(4-oxo-1(4H)-naphthalenylidene)benzenesulfonamide (A), benzenesulfonamide (B) and 4-oxo-1(4H)-naphthalenylidene (C) were selected to improve the statistic of the present 3D-QSAR models. The best models with combination of standard field in CoMFA, and steric field and electrostatic field in CoMSIA derived from the template, B and C, because most of the compounds tend not to be aligned in template A. From the based on the CoMFA and CoMSIA contour maps, the $R_1$ and $R_2$ groups on 4-oxo-1(4H) naphthalenylidene ring are steric favor. The ortho position on the benzenesulfonyl ring is steric disfavor and the meta position is steric favor. In addition, the oxygene atom of carbonyl group will have better inhibition activities as it has a negative charge favor. From these findings, we can conclude that the analyses of the contour maps provided insight into possible modification of molecules for effective inhibitiors.

• Journal of Microbiology and Biotechnology
• /
• 제19권5호
• /
• pp.520-524
• /
• 2009

Two isolates, Bacillus sp. BS87 and RK1, selected from soil in strawberry fields in Korea, showed high levels of antagonism towards Fusarium oxysporum f. sp. fragariae in vitro. The isolates were identified as B. velezensis based on the homology of their gyrA sequences to reference strains. BS87 and RK1 were evaluated for control of Fusarium wilt in strawberries in pot trials and field trials conducted in Nonsan, Korea. In the pot trials, the optimum applied concentration of BS87 and RK1 for pre-plant root-dip application to control Fusarium wilt was $10^5$ and $10^6$ colony-forming units (CFU)/ml, respectively. Meanwhile, in the 2003 and 2005 field trials, the biological control efficacies of formulations of RK1 were similar to that of a conventional fungicide (copper hydroxide) when compared with a non-treated control. The RK1 formulation was also more effective than BS87 in suppressing Fusarium wilt under field conditions. Therefore, the results indicated that formulations of B. velezensis BS87 and RK1 may have potential to control Fusarium wilt in strawberries.

• 대한수학회보
• /
• 제54권1호
• /
• pp.17-28
• /
• 2017

In this paper, we deal with a class of mean-field backward stochastic differential equations (BSDEs) related to finite state, continuous time Markov chains. We obtain the existence and uniqueness theorem and a comparison theorem for solutions of one-dimensional mean-field BSDEs under Lipschitz condition.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2001년도 추계학술대회논문집B
• /
• pp.211-216
• /
• 2001

Flow motion and variation of thermal field around a bubble which attached at the upper cooled solid wall in a $B\dot{e}nard$ convection flow is studied experimentally using thermo-sensitive liquid-crystal tracers and image processing for flow visualization and analysis. The air is injected gradually by $0.1m\ell$ to make the bubble. As the growing of the bubble in a $B\dot{e}nard$ convection flow, the variation of temperature field and surface tension along the bubble, which in turn cause to change the thermal field patterns and the flow direction and patterns. 6 cells flow pattern is transformed into diverse flow pattern. At the large size of a bubble, it's only conduction mechanism under the region of the bubble because of low Ra number 1137, but the convection flow both sides of the bubble leads to another convection flow in the bubble influence area which has been remained stable stagnation.

• 대한기계학회논문집A
• /
• 제25권6호
• /
• pp.959-964
• /
• 2001

An experimental investigation on the near-field electromagnetic loss of thin copper layers has been presented using microfabricated microwave transceivers for applications to multi-chip microsystems. Copper layers in the thickness range of 0.2$\mu$m∼200$\mu$m have been electroplated on the Pyrex glass substrates. Microwave transceivers have been fabricated using the 3.5mm$\times$3.5mm nickel microloop antennas, electroformed on the silicon substrates. Electromagnetic radiation loss of the copper layers placed between the microloop transceivers has been measured as 10dB∼40dB for the wave frequency range of 100MHz∼1GHz. The 0.2$\mu$m-thick copper layer provides a shield loss of 20dB at the frequencies higher than 300MHz, whereas showing a predominant decreases of shield loss to 10dB at lower frequencies. No substantial increase of the shield effectiveness has been found for the copper shield layers thicker that 2 $\mu$m.

• 한국수산과학회지
• /
• 제5권3호
• /
• pp.71-75
• /
• 1972

1970년 6월부터 10월까지 경남 창원군 진동면 이명리 산 진주담치(Mytilus edulis)를 충남 당진의 염전저수지로 이식하여 그의 생장을 연구하였다. 1. 6월 20일 부터 7월 19일 까지의 기간 중 염전저수지 내의 수온은 $22.5-27.5^{\circ}C$, 염도는 $28.6-34.8\%$, 해수비중은 $1.019\~1.024$, 그리고 pH는 7.6이었다. 2. 3종의 복족류와 7종의 부족류가 채집되었다. 3. 염전저수지에서 최고빈도의 진주담치군의 각고가 6월 15일에는 20mm ($15\~25mm$)이던 것이 9월 26일에는 40mm ($20\~50mm$)로 증가하였다. 한편 그들의 평균 각고는 각 각 19.80mm(6월15일)와 35.10mm (9월26일)이었다. 4. 7월 10일 부터 8월 12일 까지의 기간 중 진주담치의 1일 생장은 각고 0.22mm이었고 이는 시험 기간 중 최고치인 것이었다. 5. 진주담치 치패의 각장(L)과 각고(H) 사이, 그리고 각장(L)과 각폭(B) 사이의 생장관계식은 각 각각 1.26776L+5.07978과 B=0.3S041L+3.05502이다. 6. 이상의 결과들로부터 염전저수지에서의 진주담치 양식치 가능한 것으로 시사된다.

• Journal of Magnetics
• /
• 제2권1호
• /
• pp.1-6
• /
• 1997

The magnetic and magnetostrictive properties of melt-spun ribbons of the alloys (R0.33Fe0.67)1-xBx (R=Tb0.3Dy0.7 and 0$\leq$x$\leq$0.06) are ivestigated as a function of wheel speed during melt-quenching. The saturation magnetiation of the alloys with a crystalline phase ranges from 70 to 80 emu/g and does not vary substantially with the B content. The saturation magnetization of an amorphous phase, which is formed at the condition of thigh wheel speed and high B content, is reduced significantly, however. The coercive force is minimum at x= 0.02 and increases monotonously with the further increase of B content when the microstructure mainly consists of a crystalline phase, but again it is reduced significantly by the formation of an amorphous phase. The low field sensitivity of magnetostriction with magnetic field is found to be good for the alloys with x$\leq$0.04 over a wide range of wheel speed. This magnetostrictive behavior is in contrast with that observed previously for Dy-Fe and Tb-Fe based alloys and is thought to be due to low intrinsic magnetocrystalline anisotropy of the compound.

• 대한수학회보
• /
• 제59권5호
• /
• pp.1305-1315
• /
• 2022

Let u be a function on a connected finite graph G = (V, E). We consider the mean field equation (1) $-{\Delta}u={\rho}\({\frac{he^u}{\int_Vhe^ud{\mu}}}-{\frac{1}{{\mid}V{\mid}}}\),$ where ∆ is 𝜇-Laplacian on the graph, 𝜌 ∈ ℝ\{0}, h : V → ℝ⁺ is a function satisfying min_x∈V h(x) > 0. Following Sun and Wang [15], we use the method of Brouwer degree to prove the existence of solutions to the mean field equation (1). Firstly, we prove the compactness result and conclude that every solution to the equation (1) is uniformly bounded. Then the Brouwer degree can be well defined. Secondly, we calculate the Brouwer degree for the equation (1), say $$d_{{\rho},h}=\{{-1,\;{\rho}>0, \atop 1,\;{\rho}<0.}$$ Consequently, the equation (1) has at least one solution due to the Brouwer degree d_𝜌,h ≠ 0.