• 한국환경과학회지
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• 제15권12호
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• pp.1109-1117
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• 2006

To investigate the influence of the mesophyll cells on stomatal opening in response to white light, the segments of isolated epidermis were transferred on partly exposed mesophyll cells of a leaf and stomatal apertures were measured. Transferring the isolated epidermis on partly exposed mesophyll cells of a leaf caused a marked increase on stomatal apertures while stomata in isolated epidermis incubated in MES buffer hardly opened. Mesophyll infiltration with photosynthetic inhibitors (DCMU, DCCD, $NaN_3$) was performed to elucidate the correlation between stomatal apertures and the degree of photosynthetic activity. It was found that transferring the isolated epidermis on partly exposed mesophyll cells of a leaf caused an increase of stomatal apertures depending on the degree of photosynthetic activities. In $NaN_3$ infiltrated leaf discs, transferring the fresh isolated epidermis on partly exposed mesophyll cells of a leaf showed no significant effect, but a slight increase on stomatal apertures. Isolated epidermis alone did not respond to the light properly, but if it was closely contacted with mesophyil cells, the stomata regained the ability of the light response. Therefore, it could be suggested that stomatai apertures were related with the degree of photosynthetic activity in the mesophyll cells.

• 한국광학회지
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• 제15권3호
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• pp.258-262
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• 2004

검출기의 분광감응도 표준으로부터 출발하여 SI 기본 단위의 하나인 칸델라(candela)눈금의 불확도는 복사계 개구의 면적 측정 불확도에 의해서 제한을 받는다. 칸델라 눈금을 새로 실현하기 위하여 다이아몬드 선삭가공기를 사용하여 개구의 가장자리가 칼날과 같도록 가공하였다. 이 개구를 디지털 되먹임 알고리듬을 채용한 x-y 이송대에 설치한 후, 출력이 안정화된 레이저 광선을 빔 허리가 5 $\mu\textrm{m}$ 이하가 되도록 집속시키고, 이송대를 이동하면서 개구의 가장자리 좌표를 칼날주사 방법으로 검출하였다. 이 좌표들을 지나는 최적의 타원을 최소 제곱법으로 결정하여 개구의 면적으로 구하였다. 측정 불확도를 분석한 결과 제작한 장치의 면적 측정의 상대 측정 표준 불확도(k=1)는 8${\times}$$10^{-5}$이다.

• 한국광학회지
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• 제20권5호
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• pp.301-307
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• 2009

액정표시장치의 고효율 백라이트 집광시트로 활용하기 위하여 배면 개구형 집광시트를 설계 및 분석하였다. Microlens array sheet, 피라미드 array sheet, 그리고 cone array sheet에 대해서 자체 정렬에 의한 배면 개구 형성 특성을 비교 분석한 결과, microlens array sheet가 가장 우수하였고, 다음으로 피라미드 array sheet였으며, cone array sheet가 가장 부적합하였다.

• 센서학회지
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• 제29권2호
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• pp.123-127
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• 2020

In this paper, the estimation of the disparity for depth extraction in monochrome complementary metal-oxide-semiconductor (CMOS) image sensors with offset pixel apertures is presented. To obtain the depth information, the disparity information between two different channel data of the offset pixel apertures is required. The disparity is caused by the difference in the response angle between the left- and right-offset pixel aperture images. A depth map is implemented by the generated disparity. Therefore, the disparity is the most important factor for realizing 3D images from the designed CMOS image sensor with offset pixel apertures. The disparity is influenced by the pixel height and offset value of the offset pixel aperture. To confirm this correlation, the offset value is set to maximum within the pixel area, and the disparity values corresponding to the difference in the heights are calculated and compared. The disparity is derived using the camera-lens formula. Two monochrome CMOS image sensors with offset pixel apertures are used in the disparity estimation.

• 한국전자파학회논문지
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• 제23권12호
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• pp.1399-1405
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• 2012

무한 도체 평면에 H-형태와 C-형태의 소형 개구가 놓여져 있는 경우에 평면파가 입사될 때 투과 효율의 척도인 투과 단면적의 특성을 분석하였다. 동일한 개구 면적에서 C-형태 개구가 H-형태 개구보다 더욱 큰 투과 단면적이 나타남을 알 수 있었다. 두 개의 C-형태 개구가 인접해 놓여 있을 때 투과 단면적의 특성 관점에서 상호 결합 효과를 연구하는데 보다 관심을 두었고, 투과 단면적이 더욱 증대된다는 관점을 두고 두 개의 C-형태 개구가 x축으로 놓여있는 평행 배열 구조와 C-형태 개구가 y축으로 놓여있는 동일선상 배열 구조를 조사하였다.

• 대한전자공학회논문지
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• 제26권11호
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• pp.1752-1758
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• 1989

For many different types of apertures the diffraction phenomenon on the electromagnetic wave is analyzed by unsing Kirchhoff and Fresnel's diffraction theory. The signal intensity in variation of aperture's parameters is numerically calculated by a computer. To obtain the experimental data many types of apertures were made on an acryl board on which a special materical Elecoat was painted for preventing some reflections on the board surface and transmissions through it. Two Yagi antennas were used for a transmitting and receiving antenna and the frequency was 820MHz. The theoretichal values agreed reasonably with experimental data and these results will be used for a system design in the mobile communication between many buildings in the middle of a city.

• 전자공학회논문지A
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• 제33A권11호
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• pp.70-77
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• 1996

In this paper, a modifed TE$_{113}$/TM$_{012}$ triple-mode bandpass filter is implemented by using a modified inter-cavity iris in which the number of slots are reduced upto 50%. In a coventioanl iris two prirs of slot apertures are used to independently couple three resonant modes between two adjacent cavities. However, if transverse magnetic polarizability of a pair of veritcal slot apertures is used to control weak horizontal TE$_{h}$-TE$_{h}$ mode coupling, the width of novel iris slots would substitute for the slot length of the conventional iris, causing to eliminate the horizontal slot apertures. The measured data of two filters, which are the modified filter and ocnventional one, are compared. Experimental result shows that the characteristics of the novel triple-mode filter matches well that of the conventional filter.

• 한국전자파학회논문지
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• 제11권1호
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• pp.63-67
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• 2000

In this paper, the electromagnetic interference of a parallel plate with apertures is characterized by the method of moment(MoM), using the Spline-type Divided-Difference Interpolation(SDDI) technique. Particularly, for the solution of the problem, the application of the SDDI technique is extended to the calculation of the summation-type Green's functions. It improves numerical efficiency, having accuracy and saving the overall computational time required in the MoM application. For validating the proposed method, the electric fields on the apertures are calculated and compared to those of the literature. The numerical results show good agreement with them.

• Nuclear Engineering and Technology
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• 제30권6호
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• pp.485-495
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• 1998

Migration characteristics of tracers in a rock fracture in a case of line-source and line-collection was studied. The fracture plane was discretized into a square mesh to which variable apertures were assigned. The spatially varying apertures of a fracture were generated using a geostatistical method, based on a given aperture probability density distribution and a specified spatial correlation length. The flow potential and pressure at each node were computed. Calculations showed that fluid flow occurs predominantly through a few preferred paths. Hence, the large range of apertures in the fracture gives rise to flow channeling. The solute transport was calculated using a particle tracking method. The migration plumes of tracer between injection line and withdrawal line are displayed in contour plots. The elution curves are shown to be controlled by the aperture density distribution and to be insensitive to statistical realization and spatial correlation length.

• Architectural research
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• 제2권1호
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• pp.41-46
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• 2000

The sawtooth skylight is an excellent daylighting concept for the uniform interior illuminance over large working areas. In computer simulation, it is difficult for an architect to get accurate daylight illuminances for the spaces where sawtooth apertures are applied. In this study, daylight prediction algorithms for sawtooth apertures are developed. The flux transfer method is applied for this study to predict daylight illuminances. The simplified equations from this study can be used effectively for preliminary prediction of daylight in sawtooth spaces.