• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.4
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• pp.71-77
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• 1998

In this paper, algeration of electical characteristics is analyzed when the operating temperature of MOSFET, BJT and CMOS/BiCMOS inverter is lowered from 300K to 77K. As the operating temperature is lowered, electric characteristics of MOSFET are enhanced generally but, those of bipolar transistor are degraded because current gain is reduced by BGN(Band Gap Narrowing) effect. For the inverter considered in this work, switching characteristics of PSA-BiCMOS inverter are enhanced by the electrical characteristics enhancement of MOSFET when the operating temperature is reduced to 200K, while under 200K, those of PSA-BiCMOS inverter are degraded because the degradation of BJT impacts on the inverter circuit.

• The Korean Journal of Cytopathology
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• v.4 no.2
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• pp.156-159
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• 1993

Cryptococcosis is a systemic mycosis that most often involves the central nervous system, followed by subclinical or symptomatic pulmonary involvement. We describe a case of unsuspected pulmonary cryptococcosis in a 69-year-old woman, diagnosed by sputum cytology. Sputum smears revealed numerous yeast like organisms typical of Cryptococcus neoformans measuring from 7 to 17 um in diameter. Mucicarmine, PAS, and methenamine sliver stains showed positive reaction of capsule and cell wall of Cryptococcus neoformans.

• Journal of Yeungnam Medical Science
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• v.8 no.2
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• pp.209-216
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• 1991

Acute Megakaryoblastic leukemia is a rare and rapidly fatal disease characterized by proliferation of megakaryocyte series and atypical megakaryocytes in the bone marrow. Acute Megakaryoblastic leukemia is suspicious when 1) megakaryocyte in peripheral blood, mixture of large and small mononuclear megakaryoblast in the bone marrow 2) cytoplasmic budding in blast 3) myelofibrosis (dense medullary overgrowth of reticulin fibers) 4) PAS(+), ANAE(+), SBB(-), peroxidase(-) and which is confirmed by platelet peroxidase oxidation on electromicroscope or monoclonal antibody. A case of aute megakaryoblastic leukemia was studied morphologically and monoclonal antibody.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11b
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• pp.506-512
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• 2000

Performance of a four- wheel tractor fabricated by Tongyang Moolsan Co., Ltd, Korea was tested in Thailand during May-June 2000. Wheel slip and field capacity were measured in three fields using different traction devices and implements. The tractor worked satisfactorily in the test conditions. Wheel slip of 26.05-33.63 % and the field capacity of 0.17 - 0.20 ha/hr were observed during plowing operation. Further tractive performance tests using a three-point linkage configuration are recommended in Thailand field conditions. Different designs of cage wheels are recommended to be tested to optimize the tractive performance.

• Proceedings of the KSRS Conference
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• 2008.03a
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• pp.63-66
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• 2008

2010년 5월에 발사 예정인 KOMPSAT-5(KOrea Multi-Purpose SATellite-5)는 KOMPSAT-1, 2호에 탑재된 광학센서와는 달리 기상상태와 태양고도에 제약을 받지 않고 자료 획득이 가능한 SAR 시스템이 탑재된다. 본 연구에서는 KOMPSAT-5의 SAR 시스템으로부터 radargrammetry 기법을 적용하기 위해 위성의 궤도와 영상 모드를 분석하였다. Radargrammetry 적용을 위한 SAR 영상 pair의 parallax의 height sensitivity를 이론상으로 계산하였다. 그리고 STK 소프트웨어를 사용하여 대전과 남극 세종기지에서의 최적 조건을 각각 예시하였다. 입사각이 20$^{\cric}$-45$^{\cric}$가 되는 nominal mode의 descending pass만을 사용하여 height sensitivity가 0.5-0.75 사이의 영상 조합을 찾았다. 그 결과 Pass Number 쌍으로서, 대전은 5-4, 7-5, 8-5의 영상 조합을 하였을 때 radargrammetry 적용이 용이하고, 남극 세종기지는 8-6, 9-7, 10-7, 11-8, 12-8, 13-9, 14-9, 15-9, 15-10, 15-11의 영상 조합을 하였을 때 radargrammetry 적용이 가능한 것으로 예측되었다.

• Journal of Korean Institute of Industrial Engineers
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• v.28 no.4
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• pp.425-434
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• 2002

Mobility of service users makes location update and paging (L/P) procedures indispensable features in mobile communication networks. Importance of optimizing the configuration of L/P areas has been increased by the growth of L/P related signaling. In this study, we deal with the L/P configuration which an LA (Location Area) may contain multiple PAs (Paging Areas). Given the network topology, L/P related parameters, and traffics generated by each cell, is provided the problem of finding optimal LA/PA configuration minimizing the amount of L/P related signaling. The optimization problem is solved using a simulated annealing, and detailed computational results are conducted to capture the effects of mobility, call arrival patterns and boundary crossing rate on the LA and PA configurations.

• YAKHAK HOEJI
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• v.18 no.4
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• pp.243-248
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• 1974

Nine benzoxazolin-2-thione derivatives were sunthesized as the potential antimicrobial substances. These compounds were tested for the antimicrobial activities using Staphylococcus aureus and Escherichia coli by way of tube dilution method. The three compounds of I, II and VII omjoboted the growth of S.aureus at the concentration of 1${\mu}$g/ml, and III,VI,VIII and IX exhibited considerable antimicrobial activities against S. aureus at the concentration of 10.m.u.g/ml. As to the growth of E. Coli, VII VII and VIII inhibited at the concentration of 1${\mu}$g/,l. II,III and IV exhibited considerable antimicrobial activities against E. coli at the concentration of 10${\mu}$g/ml.

• Proceedings of the Korean Information Science Society Conference
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• 2000.10b
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• pp.281-283
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• 2000

본 논문은 EBCOT 알고리즘의 소개와 개선 방법을 제안한다. EBCOT 알고리즘은 웨이블릿 변환과 블록기반 bit-plane 부호화 방법을 활용한 알고리즘이다. EBCOT에서 사용하는 bit-plane 부호화 방법을 블록기반 fractional bit-plane 방법이라고 한다. 이 방법은 bit-plane 전체를 한번에 부호화하는 것이 아니라 블록으로 나누어 부호화를 수행하고 또한 하나의 bit-plane에 대하여서도 4번의 pass를 거치면서 bit의 context에 따라서 부호화를 수행한다. EBCOT는 웨이블릿 변환에 의하여 resolution 스케일러빌리티를 지원하고 fractional bit-plane 부호화에 의하여 SNR 스케일러빌리티를 지원하며 블록기반 부호화에 의하여 ROI에 대한 random 접근 기능을 지원한다. 그리고 EBCOT는 부호화가 완료된 다음에 bit reduction 과정을 수행한다. 이러한 특징들은 이전의 EZW나 SPIHT 방법에 비하여 장점들이라고 할 수 있다. 그러나 bit-plane 부호화를 수행하는 과정에서 효율을 개선할 수 있으며 본 논문은 이에 대한 방법을 제안한다.

• Journal of fish pathology
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• v.21 no.1
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• pp.45-56
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• 2008

This study was conducted to find out biological responses of bivalves exposed to organotin compound.The results of the study confirmed that tribultyltin chloride (TBTCl) induce reduction of survival rate andburrowing activity, and histopathological feature in the foot structure of the equilateral venus, Gomphinaveneriformis. The experimental period was 36 weeks. The experimental groups consisted of a control and 3TBTCl exposure groups (0.4, 0.6, 0.8 ym TBTCl L'). The survival rate and burrowing activity were record-ed daily. For histological analysis, foot tissues were fixed in Bouin' s fluid and then stained H-E stain, AB-PAS (PH 2.5) reaction and Masson's trichrome stain after having serially sectioned the tissue by paraffinmethod at thickness of 4-6 ym. The survival rate was not significantly different between the control andexposure groups for 20 weeks, but in 0.8 Um TBTCl L', it was on the decreased ever since the exposure. Theburrowing activity was not significantly different in the exposure group compared to the control up to 12weeks, but in 0.6 and 0.8 ym TBTCl L', it measured the lowest level after 20 weeks. The foot is composedof the epidermal layer, connective tissue, and muscular layer. The epidermal layer is composed of simplecolumnar, cuboidal epithelia and mucous cells. The cilia were well developed on the apical surface ofepithelium, Circular, longitudinal and transverse muscle bundle were well developed in the muscular layer.The majority mucous cells showed blue color (542c) when it subjected to AB-PAS (PH 2.5) reaction. Nohistopathological alterations in the foot were observed up to 12 weeks. After 20 weeks of exposure to 0.8 (anTBTCl L'', the foot samples of exposed G. veneriformis showed disappearance of cilia and striated borderpartially and extension of hemolymph sinus. The mucous cell increased in the marginal of foot. At 28-weekof exposure to 0.4 ym TBTCl L', it observed weekly acid (564c), neutral (264c) and mixed mucous cell. At36-week of exposure to 0.6 ym TBTCl L', it showed fragmentation of the muscle and collagen fiber bundle,and also diappearance of cilia on epithelia and edema of epithelium in 0.8 ym TBTCl L''.

• Development and Reproduction
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• v.12 no.2
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• pp.183-194
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• 2008

A variety of stem cells has been emerging as therapeutic cells that can replace organ transplantation in human liver diseases. The present study focused on whether human eyelid adipose-derived stem cells (HAD) might differentiate into functional hepatocyte-like cells in vitro. HAD were isolated from human eyelid adipose tissue. Effect of dimethyl sulfoxide (DMSO), fibroblast growth factor (FGF)-2 and FGF-4 on the hepatic differentiation of HAD have been examined in vitro. Immunocytochemical analysis and PAS staining showed that HAD cultured in both DMSO and FGF-4 exhibited the most intense staining than HAD of the other experimental groups. These HAD expressed numerous hepatocyte-related genes. Immunoblotting analyses showed that HAD cultured in the presence of DMSO and FGF-4 secreted higher amount of human albumin than HAD cultured in other conditions. Urea analysis also demonstrated that these HAD produced higher amount of urea than any other groups of HAD. In conclusion, combined treatment of DMSO and FGF-4 could effectively induce the functional differentiation of HAD into hepatocyte-like cells.