• Tuberculosis and Respiratory Diseases
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• 제58권2호
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• pp.111-119
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• 2005

The introduction of high-resolution CT (HRCT) in recent years has improved the ability of radiologists to detect and characterize the diffuse infiltrative lung disease (DILD). The detection and diagnosis of diffuse lung disease using HRCT are based on the recognition of specific abnormal findings. In this article, pattern recognition of HRCT findings is reviewed in the differential diagnosis of diffuse infiltrative lung disease. In general, HRCT findings of lung disease can be classified into four categories based on their appearances. These categories consist of (1) nodules and nodular opacities, (2) linear and reticular opacities, (3) increased lung opacity, and (4) decreased lung opacity, including cystic lesions.

• Journal of Biosystems Engineering
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• 제23권5호
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• pp.439-444
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• 1998

Effects of the number of spans, orientation and latitude on the transmissivities of direct and diffuse solar radiation in multispan glasshouse were analyzed using a computer simulation model (Kim and Lee, 1997). The number of spans did not affect the transmissivity of diffuse solar radiation, ranging 60∼61%. The transmissivities of direct solar radiation were 55∼64% for E-W orientation and 47∼70% for N-S orientation in ten multispan glasshouse. There was no effect of the latitude on the transmissivity of direct solar radiation in domestic regions. Differences in the transmissivity of direct solar radiation between single-span and multispan glasshouse were significant for E-W orientation during winter season; however, those were relatively small for N-S orientation throughout the year. Transmissivity of direct solar radiation decreased with the increasing number of spans for E-W glasshouse, whereas those for N-S glasshouse was hardly affected by the number of spans.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 춘계학술대회논문집
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• pp.61-64
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• 2007

This study is dealt with a method to enhance low-frequency diffuse sound field in a scaled reverberation chamber. Because scaled reverberation chamber has not enough room volume, as a result, it shows a few room modes. So it is not build up low-frequency diffuse sound field. A Helmholtz resonator's arrangement is used to improve spatial uniformity of sound pressure at low frequency. The spatial distribution of sound field has been measured before and after control. The standard deviation of sound field has decreased at 315Hz 1/3 Octave band.

• 한국세라믹학회지
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• 제24권6호
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• pp.586-592
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• 1987

The role of the strain energy and phase stability in the diffuse phase transition have been investigated in the highly disordered solid solution, (Pb1-xBax)(Zr0.4Ti0.6)O3 (0.2 x 0.4). X-ray diffraction analysis indicates that tetragonality (c/a) decreases with the increasing Ba content. Also as the Ba content increases, phase transition becomes more diffuse and at the same time dielectric relaxation as a function of measured frequencies in the 1KHz-10MHz range occurs very pronouncedly. In the Ba content range, 0.2 x 0.35, hysteresis loops are routinely observed and the loop is observed to narrow shape as the Ba content increases but becomes very slim at 40mol% Ba content. Moreover thermal analysis shows that there is no abrupt change in the thermal expansion coefficient below the apparent transition temperature at which dielectric constant becomes maximum. From the above results, it has been concluded that creation of the strain energy due to the distorthion that occurred during the phase transition suppresses diffuse phase transition.

• 대한세포병리학회지
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• 제10권1호
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• pp.85-89
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• 1999

An extremely unusual case of epidermoid cyst showing diffuse parakeratosis and aggressive clinical behavior is presented. A destructive bone lesion with surrounding ill-defined soft tissue lesion was found by computed tomography in a 63 year-old man complaining of painful swelling of the right buttock. He had a history of surgical excision twice for epidermoid cysts of soft tissue of the right hip during recent one year On aspiration cytology, the aspirate was highly cellular and mostly composed of desquamated nucleated squamous cells. Operation finding revealed that the iliac bone was Irregularly destroyed and filled with gray-white cheesy material and necrotic bone bedris. Adjacent gluteus muscle showed scattered gray-white lesions. The curettage specimen showed bone necrosis and desquamated squamous cells filling the marrow spaces. The lesion within muscle revealed epidermoid cyst with diffuse parakeratosis.

• 한국태양에너지학회 논문집
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• 제31권6호
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• pp.86-94
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• 2011

For accurate dayligh tsimulation, accurate exterior illuminance is necessary. But, Korea Meteorological Agency provides only the solar irradiance data. Thus, there is a need for the research on luminous efficacy. In this study, global horizontal irradiance, diffuse horizontal irradiance, global horizontal illuminance, and diffuse horizontal illuminance were measured to calculate the luminous efficacy in SEOUL. And, we evaluated the applicability of the Perez's model by comparing the measured data and calculated data. As a result, measured global luminous efficacy is 126(110~129)lm/W and diffuse luminous efficacy is 127(115~133)lm/W in Seoul. Perez's model was relatively accurate with 5% difference in the diffuse luminous efficacy. But, it can be predicted about 15% lower in the global luminous efficacy.

• 한국광학회지
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• 제22권3호
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• pp.134-140
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• 2011

본 논문에서는 생체 내부를 비침습적으로 영상화하기 위한 방법으로 생체내에서의 빛의 전파가 흡수보다는 산란이 지배적으로 작용하는 근적외선(NIR, near-infrared) 영역의 레이저 광원 및 광 검출기를 이용하여 주파수영역(frequency-domain) 확산 광 단층촬영(DOT, diffuse optical tomography) 시스템을 구현하였으며, 생체조직을 모사한 액체 팬텀에 광학적 특성이 다른 이형성분(anomaly)을 삽입하여 실험적으로 흡수 및 산란 분포에 대한 영상을 복원함으로써 이형성분의 위치와 형태에 대한 정보를 획득하였다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 1999년도 춘계학술발표강연 및 눈문개요집
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• pp.112-112
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• 1999

• Bulletin of the Korean Chemical Society
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• 제25권10호
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• pp.1461-1462
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• 2004

• 천문학회지
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• 제38권2호
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• pp.215-218
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• 2005

An atlas of high resolution (${\lambda}/{\Delta}{\lambda}$=45,000) profiles of interstellar atomic lines of K I (7665, 7699 ${\AA}$), Na I (D 1, D2), Ca II (H, K), Ca I (4227 ${\AA}$), molecular structures of CH, CH+, CN and the major diffuse interstellar bands at 5780 and 5797 ${\AA}$ based on ${\~}$300 echelle spectra of ${\~}$200 OB stars is presented. Relationships between the reddenings, distances and equivalent widths of NaI, CaII, KI, CH, CH+, CN and diffuse bands are discussed. The equivalent width of K I (7699 ${\AA}$) as well as of CH4300 ${\AA}$ / correlate very tightly with E(B- V) in contrast to the features of neutral sodium, ionized calcium and the molecular ion CH+. The equivalent widths of the Hand K lines of Call grow with distance at a rate ${\~}$250m${\AA}$ per 1 kpc. A similar relation for NaI is much less tight. The strengths of neutral potassium lines, molecular features and diffuse interstellar bands do not correlate practically with distance. These facts suggest that ionized calcium fills the interstellar space quite homogeneously while the other carriers mentioned above, especially K I, CH and these of diffuse bands occupy more and more compact volumes, also filled with dust grains. Apparently the carriers of narrow diffuse bands are spatially correlated with simple molecules and dust grains - all abundant in the so-called 'zeta' type clouds. The same environment seems to be hostile to the carriers of broad diffuse interstellar bands (DIEs) (like 5780 or 6284) and -to a certain extent - also to CaII, NaI and CH+.