• Journal of the Korean Institute of Gas
• /
• v.11 no.2 s.35
• /
• pp.31-36
• /
• 2007

In order to study on the corrosion characteristics of STS 304 pipeline steel weldment for gas cooling & heating system. the electrochemical polarization test and corrosion test by impressed potential in 0.5M $H_2SO_4+0.01M$ KSCN solution was carried out. Also, SEM and hardness of welding zone was measured. And then passive behavior, corrosion behavior by the impressed potential and SEM aspect and hardness behavior of base metal(BM) and heat affected zone(HAZ) for STS 304 pipe were investigated. The main results are as follows: 1) The critical anodic current density of heat affected zone(HAZ) is drained more highly than that of base metal(BM), and primary passive potential of HAZ become higher than that of BM. 2) The passive current density of TUE is drained more highly than that of BM, and passive region of BM become bigger than that of HAZ. 3) By the impressed potential, the current density of HAZ is drained more than that of BM.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.23 no.1
• /
• pp.123-128
• /
• 2011

1-Deoxynojirimycin (DNJ) is an alkaloid that is found at relatively high concentrations in mulberry leaf and tissues of the silkworm, $Bombyx$ $mori$. DNJ is a well known inhibitor of ${\alpha}$-glucosidase, an enzyme that is involved in the early stages of the $N$-linked glycoprotein synthesis pathway. ${\alpha}$-Glucosidase activity in the cell extract from $B.$ $mori$-derived Bm5 cells showed approximately 40-fold less sensitivity to DNJ than ${\alpha}$-glucosidase activity in the cell extract from $Spodoptera$ $frugiperda$-derived Sf9 cells. The replication of $B.$ $mori$ nucleopolyhedrovirus (BmNPV) was not inhibited when it was propagated in BmN cells that were grown in medium containing up to 10 mM DNJ. In contrast, the replication of $Autographa$ $californica$ multiple NPV (AcMNPV) was reduced by 67% when it was propagated in Sf9 cells that were grown in medium containing 10 mM DNJ. The viability of Bm5 and Sf9 cells that were grown in medium containing up to 10 mM DNJ was not affected. Our results suggested that the reduced replication of AcMNPV was the result of the higher sensitivity of ${\alpha}$-glucosidase activity in Sf9 cells to DNJ.

• Journal of IKEEE
• /
• v.20 no.3
• /
• pp.279-284
• /
• 2016

This paper presents a two stage L-band power amplifier realized with a $0.32{\mu}m$ Silicon-On-Insulator (SOI) CMOS technology. To overcome a low breakdown voltage limit of MOSFET, stacked-FET structures are employed, where three transistors in the first stage amplifier and four transistors in the second stage amplifier are connected in series so that their output voltage swings are added in phase. The stacked-FET structures enable the proposed amplifier to achieve a 21.5 dB small-signal gain and 15.7 dBm output 1-dB compression power at 1.9 GHz with a 122 mA DC current from a 4 V supply. The amplifier delivers a 19.7 dBm. This paper presents a two stage L-band power amplifier realized with a $0.32{\mu}m$ Silicon-On-Insulator (SOI) CMOS technology. To overcome a low breakdown voltage limit of MOSFET, stacked-FET structures are employed, where three transistors in the first stage amplifier and four transistors in the second stage amplifier are connected in series so that their output voltage swings are added in phase. The stacked-FET structures enable the proposed amplifier to achieve a 21.5 dB small-signal gain and 15.7 dBm output 1-dB compression power at 1.9 GHz with a 122 mA DC current from a 4 V supply. The amplifier delivers a 19.7 dBm saturated output power with a 16 % maximum Power Added Efficiency (PAE). A bond wire fine tuning technology enables the amplifier a 23.67 dBm saturated output power with a 20.4 % maximum PAE. The die area is $1.9mm{\times}0.6mm$.

• IMMUNE NETWORK
• /
• v.11 no.5
• /
• pp.281-287
• /
• 2011

Background: Biodegradable polymers have increasingly been recognized for various biological applications in recent years. Here we examined the immunostimulatory activities of the novel poly(aspartic acid) conjugated with L-lysine (PLA). Methods: PLA was synthesized by conjugating L-lysine to aspartic acid polymer. PLA-nanoliposomes (PLA-NLs) were prepared from PLA using a microfluidizer. The immunostimulatory activities of PLA-NLs were examined in mouse bone marrow-derived dendritic cells (BM-DCs). Results: PLA-NLs increased the number of BM-DCs when added to cultures of GM-CSF-induced DC generation on day 4 after the initiation of cultures. Examination of the phenotypic properties showed that BM-DCs generated in the presence of PLA-NLs are more mature in terms of the expression of MHC class II molecules and major co-stimulatory molecules than BM-DCs generated in the absence of PLA-NLs. In addition, the BM-DCs exhibited enhanced capability to produce cytokines, such as IL-6, IL-12, TNF-${\alpha}$ and IL-$1{\beta}$. Allogeneic mixed lymphocyte reactions also confirmed that the BMDCs were more stimulatory on allogeneic T cells. PLA- NL also induced further growth of immature BM-DCs that were harvested on day 8. Conclusion: These results show that PLA-NLs induce the generation and functional activities of BM-DCs, and suggest that PLA-NLs could be immunostimulating agents that target DCs.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.18 no.1
• /
• pp.8-12
• /
• 2009

A study has been made to know the effect of a phytoecdysteroid 'Sampoorna' on uniform maturation of silkworms during spinning and its effect on diseased silkworms infected by major silkworm disease viruses, Bombyx mori nuclear polyhedrosis virus (BmNPV) and Bombyx mori infectious flacherie virus (BmIFV). In the present investigation, the effect of the phytoecdysteroid "Sampoorna" on Grasserie disease caused by BmNPV have shown an average cocoon melting of 11.91% with a disease incidence of 5.83%. The values of 't' test for different treatments of BmNPV indicated low survival rate and cocoon traits were drastically reduced. Another major disease Flacherie caused by BmIFV has shown considerable levels of larval disease incidence (22-32%) and cocoon melting (3-7.67%) with an average melting of 12.95% and 20.24% disease incidence. There is a drastic reduction in survival rate, cocoon yield and other economic traits. The control batches were indicated negligible values for disease incidence and cocoon melting with Sapoorna application and without the inoculation of the two disease-causing viruses. The application of Sampoorna on already infected batches with major pathogens triggered high mortality and disease incidence and melting percentage was also significantly increased with reduced economic traits. Hence, it is suggested that application of Sampoorna in infected batches should be done only in the extreme conditions of rearing. Application of Sampoorna on healthy batches led to uniform maturation and improvement in productivity with the added advantage of better quality cocoons and labour saving.

• Neonatal Medicine
• /
• v.25 no.2
• /
• pp.58-65
• /
• 2018

Purpose: The purpose of this study is to describe the rate of cytomegalovirus (CMV) virolactia, and the prevalence of breast milk (BM)-transmitted postnatal CMV infection among premature infants after freeze-thawing (FT) and Holder pasteurization (HP) of breast milk. Methods: This is a single-center, retrospective study of 312 infants born at less than 32 weeks of gestation, or with a birth weight less than 1,500 g from January 2013 to June 2017. All infants were screened for CMV-specific immunoglobulin (Ig) G and IgM at birth. Initial CMV specific polymerase chain reaction (PCR) and CMV culture were performed on mothers' BM and babies' urine within the first 21 days of life. FT and HP of BM was used to prevent the transmission of CMV. For the surveillance of postnatal CMV infection, CMV culture and CMV specific PCR of urine from babies were repeated one to two months after the initial screening. Screening for viremia and viruria was performed if postnatal CMV infection was suspected. Results: Among 178 BM samples obtained from mothers of CMV-IgG-seropositive infants, 80 (44.9%) were CMV PCR positive. CMV deoxyribonucleic acid (DNA) was detected in five of the 22 BM samples (22.7%) obtained from the mothers of CMV-IgG seronegative infants. When CMV DNA load in BM was measured before and after HP, various results were shown. Sixty-three infants out of 232 (27.2%) were evaluated for postnatal CMV infection and four infants out of 63 (6.3%) were infected. Conclusion: Interventions to prevent BM-transmitted CMV infection can reduce the chance of postnatal CMV infection, but not completely eliminate it.

• Asian-Australasian Journal of Animal Sciences
• /
• v.25 no.6
• /
• pp.800-805
• /
• 2012

Rice straw is an important roughage resource for ruminants in many rice-producing countries. In this study, a rice brittle mutant (BM, mutation in OsCesA4, encoding cellulose synthase) and its wild type (WT) were employed to investigate the effects of a cellulose synthase gene mutation on rice straw morphological fractions, chemical composition, stem histological structure and in situ digestibility. The morphological fractions investigation showed that BM had a higher leaf sheath proportion (43.70% vs 38.21%, p<0.01) and a lower leaf blade proportion (25.21% vs 32.14%, p<0.01) than WT. Chemical composition analysis showed that BM rice straw was significantly (p<0.01) higher in CP (crude protein), hemicellulose and acid insoluble ash (AIA) contents, but lower in dry matter (DM), acid detergent fiber (ADFom) and cellulose contents when compared to WT. No significant difference (p>0.05) was detected in neutral detergent fiber (NDFom) and ADL contents for both strains. Histological structure observation indicated that BM stems had fewer sclerenchyma cells and a thinner sclerenchyma cell wall than WT. The results of in situ digestion showed that BM had higher DM, NDFom, cellulose and hemicellulose disappearance at 24 or 48 h of incubation (p<0.05). The effective digestibility of BM rice straw DM and NDFom was greater than that of WT (31.4% vs 26.7% for DM, 29.1% vs 24.3% for NDFom, p<0.05), but the rate of digestion of the slowly digested fraction of BM rice straw DM and NDF was decreased. These results indicated that the mutation in the cellulose synthase gene could improve the nutritive value of rice straw for ruminants.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.10 no.8
• /
• pp.1817-1823
• /
• 2009

A design of cascaded distributed amplifier with a broadband amplification is described in this paper. A medium power device with 23dBm, max output power under the optimal narrow-band power matching condition is adopted for the design and fabrication of the cascaded distributed amplifier. In general, conventional distributed amplifiers with the parallel connected input ports have a low gain, and previous cascaded distributed amplifiers show a relatively low output power of 10dBm at most, which is the upper limit of small signal amplification. However, the cascaded distributed amplifier in this paper shows the gain of $18.15{\pm}0.75dB$ and output power of 20dBm over $300MHz{\sim}2GHz$ from the measurement, so it can be well adopted as a wideband driver amplifier.

• Proceedings of the KIEE Conference
• /
• 2001.11c
• /
• pp.435-437
• /
• 2001

본 논문은 BMI (Background Marking 1)을 개선하여 차량의 번호판정 보를 보다 신속히 추출하는 방법에 대한 연구이다. BMI은 입력된 영상에서 각각의 화소를 비교하여 특정색상을 최고치인 255로 지정하고, 그 이외의 화소는 최저치인 0으로 표시하는 방법이다. 하지만 이 방법은 모든 화소를 처리함으로써 검색시간이 많이 소요된다는 단점을 가지고 있다. BM2는 이러한 단점을 개선하여 빠른 차량 번호판 검색 및 추출을 가능하도록 하였다. 또한 기존에 제시된 히스토그램에 기초한 검색방법은 명암의 변화에 따른 추론방법으로 조명과 잡음에 약하다는 단점을 가진다. BM2는 기존 방법과 달리 특정색상을 추출함으로써 명암의 변화에 강한 특징을 가지도록 하였다. 제안된 방법을 여러 가지지 차량 종류에 따른 영상에 적용하여 BMI보다 우수한 성능을 검증하였다.

• Korean Journal of Optics and Photonics
• /
• v.7 no.1
• /
• pp.60-65
• /
• 1996

Degradation of the optical communication system due to the stimulated Brillouin scattering effect in the optical fiber is measured, and its suppression is demonstrated. In the externally modulated 2.5 Gb/s transmission experiment, bit error rate is increased due to the stimulated Brillouin scattering effect when the signal power (linewidth 3 MHz) incident into the dispersion shifted fiber is larger than 10 dBm. SBS effect is suppressed completely, up to 15 dBm of transmission power, by broadening the source linewidth to 200 MHz.