• 한국표면공학회지
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• 제52권6호
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• pp.357-363
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• 2019

We investigated a synthesis yield and diameter distribution of single-walled carbon nanotubes (SWNTs) with respect to the growth position in a horizontal chemical vapor deposition (CVD) chamber. Thin films and line-patterned Fe films (0.1 nm thickness) were prepared onto ST-cut quartz substrates as catalyst to compare the growth behavior. The line-patterned samples showed higher growth density and parallel alignment than those of the thin film catalyst samples. In addition, line density of the aligned SWNTs at central region of the chamber was 7.7 tubes/㎛ and increased to 13.9 tubes/㎛ at rear region of the CVD chamber. We expect that the enhanced amount of thermally decomposed feedstock gas may contribute to the growth yield enhancement at the rear region. In addition, the lamina flow in the chamber also contribute to the perfect alignment of the SWNTs based on the value of gas velocity, Reynold number, and Knudsen coefficient we employed.

• Journal of Welding and Joining
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• 제23권6호
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• pp.61-66
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• 2005

A probabilistic approach for evaluating failure risk is suggested in this paper. Probabilistic fracture analyses were performed for a pressurized pipe of a Cr-Mo steel reflecting variation of material properties at high temperature. A crack was assumed to be located along the weld fusion line. Probability density functions of major variables were determined by statistical analyses of material creep and creep crack growth data measured by the previous experimental studies by authors. Distributions of these variables were implemented in Monte Carlo simulation of this study. As a fracture parameter for characterizing growth of a fusion line crack between two materials with different creep properties, $C_t$ normalized with $C^*$ was employed. And the elapsed time was also normalized with tT, Resultingly, failure probability as a function of operating time was evaluated fur various cases. Conventional deterministic life assessment result was turned out to be conservative compared with that of probabilistic result. Sensitivity analysis for each input variable was conducted to understand the most influencing variable to the analysis results. Internal pressure, creep crack growth coefficient and creep coefficient were more sensitive to failure probability than other variables.

• Asian-Australasian Journal of Animal Sciences
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• 제22권4호
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• pp.492-499
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• 2009

A Silkie Bantam embryo fibroblast line (named SBF59 line) was successfully established by using direct explant culture and cryopreservation techniques. Cell morphology, viability, dynamic growth and contamination were tested and the karyotype and levels of isoenzymes of lactic dehydrogenase and malic dehydrogenase were analyzed. Four kinds of fluorescent protein extrogenes, including $pEGFP-N_3$, $pECFP-N_1$, $pEYFP-N_1$ and $pDsRed1-N_1$ were transfected into the cells. The results showed that the cells were healthy and possessed a fibrous structure without a change in morphology. The average viability of the cells was 96% before freezing and 90.5% after thawing. The growth curve appeared as typical "S" shape and the cell growth passed through a detention phase, a logarithmic phase and a platform phase; the estimated population doubling time (PDT) was 38.5 h; assays for the presence of bacteria, fungi, viruses and mycoplasmas were negative; the cell line showed no cross contamination when assessed by isoenzyme analysis; the chromosome number was 2n = 78 on more than 88% of occasions; four kinds of fluorescent protein extro-genes appeared to be expressed effectively with a high transfection efficiency between 18.3% and 42.3%. The cell line met the required quality control standard. It not only preserves the genetic resources of the important Silkie Bantam at the cellular level but also provides valuable materials for genomic, post-genomic, somatic cell cloning research and other applications.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집A
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• pp.501-506
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• 2001

The creep crack growth properties in 3.5NiCrMoV steel were investigated at $550^{\circ}C$ by using CT specimen under constant $C_t$ condition that was held during crack growth of 1mm distance. $C_t$ lely on load line displacement rate and $C^*$ usually increase with crack length though load is reduced in order to maintain constant $C_t$ value as crack growth. Fully coalesced area(FCA) ahead of crack tip tend to increase as $C_t$ increase to the critical value, and after that value FCA decrease. For the tertiary creep stage of crack growth test, the most of displacement is due to the steady state creep, except only small part due to the primary creep and other effects. Therefore, tests were mainly interrupted in the tertiary stage to obtain high value of $C_t$. At constant load and $C_t$ region, crack growth slope was 0.900 and 0.844 each, on the other hand $C^*$ slope was 0.480.

• BMB Reports
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• 제32권3호
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• pp.266-272
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• 1999

The insulin-like growth factor (IGF) system consisting of IGF-I, IGF-II, IGF-receptors, and IGF-binding proteins (IGFBP) regulates the proliferation of a variety of cancer cell types. To examine whether a decrease in endogenous IGFBP-3 stimulates proliferation or inhibits differentiation, Caco-2 cells, a human colon adenocarcinoma cell line, were stably transfected with an anti-sense IGFBP-3 expression construct or pcDNA3 vector as control. Accumulation of IGFBP-3 mRNA and secretion of IGFBP-3 into serum-free conditioned medium, 9 days after plating, were significantly lower in Caco-2 cell clones transfected with anti-sense IGFBP-3 cDNA compared to the controls. The anti-sense clones grew at a similar rate to the controls for 8 days after plating, but achieved a higher final density between days 10 and 12. The levels of sucrase-isomaltase mRNA, a marker of enterocyte differentiation of Caco-2 cells, were lower in the anti-sense clones examined on day 9. In conclusion, proliferation of Caco-2 cells can be stimulated by lowering endogenously-produced IGFBP-3.

• 한국컴퓨터정보학회논문지
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• 제7권3호
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• pp.68-73
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• 2002

정보산업분야의 발전은 산업구조의 변화와 새로운 패러다임을 요구하는 시대로 변모하고 있다. Off-Line에서 처리하던 많은 내용들이 On-Line으로 변화의 조짐이 보이고 이러한 변화에 따라 많은 기업들이 연구와 투자가 지속적으로 이루어지고 있는 실정이다. 본 논문은 Off-Line에서만 처리되던 DM발송 시스템을 On/Off-Line의 연계를 이용하여 좀더 효율적으로 데이터를 관리할 수 있는 시스템을 제안하고자 DM발송 시스템을 설계 및 구현하였다.

• 대한수의학회지
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• 제43권2호
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• pp.211-218
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• 2003

Human ovarian cancerous cells survive in a way that they trigger the nucleotide excision repair (NER) or double-strand DNA repair (dsDNA) repair mechanism to show resistance to anticancer drugs and activate many kinds of repair protein, thus removing damaged DNAs. Two experiments on the PA-1 human ovarian teratocareinoma cell line that hardly has any expression of epidermal growth factor receptor (EGFR) were conducted in the study; first, EGF-R was transfected and its receptor was obtained. The receptor was investigated in terms of its mutual relations with many kinds of protein concerning NER or dsDNA repair. Second, it was examined what kind impact cisplatin and adriamycin had on the effects of EGF-R over the PA-1 cell line lacking EGF-R. When being administered with cisplatin and adriamycin, Hey and Hey C2 cell lines showed a high level of resistance while PA-1 cell line a high level of sensitivity. Hey and Hey C2 cell lines that are resistant against anticancer drugs exhibited a high level of EGF-R expression while PA-1 cell line that is sensitive to them did a much lower level of the expression. When PA-1 cell line was transfected for the expression of DNA adduct and EGF-R, it showed a higher level of resistance compared to the control group. There was no difference in the expression of DNA repair proteins (DNA- dependent protein kinase, Ku70, and Ku80) between Hey and the PA-1 cell lines. The results indicate that the Hey cell line that is resistant against cisplatin and adriamycin works along the signaling system responding to the changes of EGF-R while the PA-1 cell line that is sensitive to both of them does to the lack of EGF-R.

• 원예과학기술지
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• 제34권3호
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• pp.424-432
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• 2016

본 실험은 10개의 겨울정식 파프리카 품종에서 재배기간 동안 관찰되는 생육과 착과의 특성을 비교하기 위해서 수행되었다. 본 실험을 위해서 공시된 품종은 적색계 파프리카 'Maduro', 'Maranello', 'Nagano', 'Sirocco'와 'Special', 황색계 파프리카 'Coletti', 'Sven', 'Thialf', 'Volante'와 'Zagato'이었으며, 실험은 2013년 겨울부터 2014년 가을까지 42주 동안 실시되었다. 각 품종별 생육 특성의 검정은 파프리카의 생육 단계를 기준으로 하여 Group 1에서부터 Group 6까지 6회로 나누어 수행하였다. 실험에 이용된 파프리카 품종에서 생육초기 상대적 절간비율은 모든 품종에서 평균 이상의 범위를 보였다. 하지만 생육이 진전될 수록 상대적 절간비율은 감소하는 경향을 보였으며 이러한 경향은 적색계 품종에서 황색계 품종에 비해서 컸다. 여름 재배기간 동안 'Special'과 'Zagato'는 생장이 억제가 된 반면, 'Maranello'와 'Volante'은 생육균형이 잘 유지되는 것으로 나타났다. 착과율은 황색계 품종이 적색계 품종에 비해서 전체 마디수가 4.1마디 적었음에도 불구하고 적색계 품종에 비해서 10.8% 높았다. 6월과 7월에 성과기를 거친 이후에 측정된 Group 4에서의 착과량은 'Sirocco'와 'Coletti'가 다른 품종에 비해 적었던 것으로 보아 공시 품종 가운데 장마기 환경에 민감한 품종으로 판단되었다. 이상의 결과로 볼 때 측고가 높은 온실에서 여름 재배에 적합한 품종은 'Maranello', 'Nagano', 'Sven', 'Thialf', and 'Volante' 이며, 측고가 낮은 온실에서 여름재배에 적합한 품종은 'Maranello', 'Special', 'Volante'와 'Zagato'으로 판단된다.

• 방사선산업학회지
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• 제5권3호
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• pp.211-220
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• 2011

This study was carried out to develop salt tolerant varities of rapeseed (Brassica napus L.) which can be grown in the high salty reclaimed land. The seeds of three varieties 'Naehan', 'Tammi', and 'Halla' were treated by proton ion beams and gamma rays with 0 to 2,000 Gy. For the selection of salt tolerant lines, emergence and survival rate, and growth characteristics of $M_2$ to $M_4$ generations were investigated in the Saemangeum reclaimed fields with the different salt concentrations. The lines with potential salt tolerance were selected in the $M_4$ generation and tested indoor for their growth characteristics. There was no significant changes in the soil pH for $M_4$ generation during growth period. However, soil EC was higher in early spring than sowing period (mid October). In $M_4$ generation test, the seeds of original and selected line showed high rates of emergence and survival, as determined one month after sowing. After wintering, however, the original varieties showed the significant reduction in the survival rate, while the selected lines showed a higher survival rate and good growth, leading to the completion of their life cycle. Consequently we selected 9 lines from $M_4$ generation with better performance in growth and yield. Soil EC was $2.8{\sim}4.3dS{\cdot}m^{-1}$ during $M_4$ generation growth period. The laboratory test of the lines selected from $M_4$ generation was made for their salt tolerance potential. The selected lines showed higher chlorophyll and proline contents than the original varieties. There was also no significant difference in the emergence rate of seed between the original and selected varieties. In 200 mM natural sea salt, the $N{\gamma}600-21-1-641$ line derived from 'Naehan' was the highest in growth rate, leaf chlorophyll and proline contents. $T{\gamma}800-20-2-461$ line derived from 'Tammi' didn't show significant difference in growth rate compared to original variety in 200 mM and withered in 250 mM like other lines as time passed. $H{\gamma}200-7-1-740$ line showed similar growth and chlorophyll content compared to its original variety.

• 대한치과교정학회지
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• 제27권4호
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• pp.633-641
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• 1997

성장 또는 치료로 인한 악안면골의 변화는 두부 방사선을 중첩 함으로써 판단할 수 있다. 중첩에 대한 평가는 중첩방법에 따라 변화되므로 좀더 정확한 중첩 방법을 선택하는 것은 치료 효과에 대한 분석이나 성장 변화에 대한 평가를 정확히하는 선결 요건이 될것이다. 3년 정도의 비교적 짧은 성장기간을 가진 11세 전후의 여자 환자 19명을 대상으로, 가장 널리쓰이는 중첩 방법인 Nasion-Sells line중첩과 Bjork가 주장하는 Anteirior cranial base (ACB)중첩을 비교하여 다음과 같은 결론을 얻었다. 1 Nasion-Sells line중첩과 ACB중첩은 중첩오차(registration error)의 크기가 거의 같아서 reliability에 있어서 큰차이가 없는 것으로 나타났다 2. 검사자간 차이(interobserver difference)에 있어서 Nasion-Sells line중첩은 7개의 측정 항목 모두에서 두 검사자간에 차이가 없었으나 ACB중첩은 7개의 측정 항목중 4개의 측정 항목에서 두 검사자간 유의성 있는 차이가 나타났다. 3. 중첩방법의 차이 (intermethod difference)에 있어서 Nasion-Sella line중첩으로 측정한 계 측치와 ACB 중첩으로 측정한 계측치가 유의성있게 차이가 나지 않았다.