• 대한전기학회논문지
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• 제45권3호
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• pp.415-425
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• 1996

This study presents an analytical method of solving the behaviors of arc plasma in a nozzle constricting transferred-type torch and purposes to obtain the basic data for the design of a plasma torch, which can be obtained from the temperature, pressure, velocities and voltage distributions. We have to solve some conservation equations simultaneously and need to know the exact thermal gas properties in order to obtain the correct behaviors of arc plasma. It is also necessary to give the relevant physical or geometric boundary conditions. For the simplicity of analysis, we assumed that (a) the plasma flow is laminar, (b)the local thermodynamic equilibrium, i.e. LTE, prevails over the entire arc column region. The electrode sheath effects were neglected and the nozzle area was excluded from the analysis by assuming that the current flow into the nozzle is zero. We solved the momentum transfer equation including the self-magnetic pinch effect, and obtained the temperature distribution from the energy conservation equation. From this temperature, we could get arc voltage distribution. (author). refs., figs., tabs.

• 한국수정란이식학회지
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• 제9권1호
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• pp.43-48
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• 1994

This study was carried out to produce monozygotic twin calves by transfer of bisected embryos. Four Korean native cattle donors were superovulated with FSH and flushed to collect embryos on day 6 or 7 of the estrus cycle. Morula and early blastocyst embryos showed 1 or 2 grade were bisected with microblade and each set of demi-embryos without zona pellucida were transferred nonsurgically to 10 recipients respectively. The results obtained were as follows; 1. Twenty four demi-embryos (92.3%) were separated from 13 original embryos and among them 20 demi-embryos (83.3%) had normal appearance without severe damage. 2. Four sets of fresh demi-embryos were transferred to 4 recipients and one recipient was twin pregnant 3. Six sets of frozen-thawed demi-embryos were transferred to 6 recipients. Two recipients were pregnant, one of them twin.

• Journal of Microbiology and Biotechnology
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• 제30권9호
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• pp.1290-1296
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• 2020

Recently, it was reported that entire mammalian mtDNA genomes could be transplanted into the mitochondrial networks of yeast, where they were accurately and stably maintained without rearrangement as intact genomes. Here, it was found that engineered mtDNA genomes could be readily transferred to and steadily maintained in the mitochondria of genetically modified yeast expressing the mouse mitochondrial transcription factor A (Tfam), one of the mitochondrial nucleoid proteins. The transferred mtDNA genomes were stably retained in the Tfam-expressing yeast cells for many generations. These results indicated that the engineered mouse mtDNA genomes introduced in yeast mitochondria could be relocated into the mitochondria of other cells and that the transferred genomes could be maintained within a mitochondrial environment that is highly amenable to mimicry of the biological conditions in mammalian mitochondria.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 추계학술대회 논문집
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• pp.99-100
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• 2007

Transferring patterns from mold to PDMS stamp is very useful technology in micro-fabrication, complex and three-dimensional structures. First experimentation, mold's patterns wens transferred to PDMS stamp. Comparing with PDMS stamp and Mold, patterns were transferred about 97.9%. Second experimentation, PDMS stamps were made several times by only one mold, scale and distance of transferred patterns were uniform about 89.3%. We proved that transferring patterns from mold to PDMS stamp is accurate. The uniformity of stamps is the same after mold was used several times. Transferring patterns from mold to PDMS stamp has uniformity and accuracy, it will be useful technology.

• Tuberculosis and Respiratory Diseases
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• 제41권2호
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• pp.87-96
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• 1994

연구배경 : 종양괴사인자(tumor necrosis factor ; TNF)는 여러 암세포에 대해서 세포독성을 보임이 알려져 있다. 그리고, 최근 분자생물학적 발전에 힘입어 TNF 유전자를 암세포에 이입하고 발현시키는 연구가 그 동안 진행되었다. 이들 연구의 목적은, TNF를 전신적으로 쓸 경우 전신 부작용이 심하여 인체에 쓸 수 없는 현 단계에서 암세포 자체에서 TNF를 만들어 내어서 암세포 주위에서만 작용하게 함으로써 연체에 미치는 전신독성을 최소한으로 줄이고 암세포를 사멸시키는 것이었다. 암세포에 TNF 유전자를 이입함으로써 예상되는 항암효과가 성공을 거두기 위해서는 첫째, TNF 유전자가 이입된 암세포에서 분비된 TNF가 주위 암세포를 성공적으로 사멸시켜야 하고 둘째는 분비된 TNF가, TNF 유전자가 이입된 암세포 자신을 사멸시켜야 한다. 본 연구는 이 중 두번째 기전, 즉 TNF 유전자가 이입된 암세포가 자신이 분비한 TNF에 의해서 사멸되거나 또는 세포 독성이 나타날 수 있는가를 검증하는데 목적을 두었다. 방법 : TNF에 감수성을 보이는 인체의 중피종 세포주인 NCI-H2058과 생쥐 섬유육종 세포주인 WEHI164에 TNF-$\alpha$ 유전자를 retroviral vector를 이용하여 이입하고 TNF를 발현을 시도하였다. DNA 수준과 단백질 수준에서 TNF-$\alpha$ 유전자가 제대로 이입되어 발현되는지 PCR과 ELISA 및 bioassay(MTT assay)로 확인하였다. 그리고, TNF 유전자가 이입된 세포주가 자신이 분비하는 TNF에 사멸되는지 아니면 생존하는지 MTT(dimethylthiazolyl diphenyltetrazolium) assay로 알아보았다. 그리고, 만일 TNF 유전자가 이입된 암세포가 자신이 분비한 TNF에 사멸되지 않고 생존할 경우, TNF 유전자가 이입된 NCI-H2058-TNF와 WEHI164-TNF 암세포주가 외부에서 준 TNF에도 내성을 보이는지도 추가로 MTT assay 방법으로 확인해 보았다. 결과 : 1) TNF-$\alpha$ 유전자 이입 및 발현 확인 PCR을 시행한 결과, TNF 유전자가 이입된 NCI-H2058-TNF와 WEHI164-TNF 세포주는 790 base pair 크기의 진한 DNA band를 보인 반면 각각의 모세포주에서는 보이지 않아서 retroviral vector를 이용한 유전자 이입이 DNA 수준에서 이루어졌음을 확인할 수 있었다. 그리고, NCI-H2058-TNF와 WEHI164-TNF의 상층 배양액의 TNF양을 ELISA와 bioassay(MTT assay)로 측정한 결과, 생물학적 활성을 지닌 TNF를 각각 $23.6{\pm}0.84ng$/24h/$10^6cells$, $12.2{\pm}0.36ng$/24h/$10^6cells$ 생산함을 알 수 있었다. 2) TNF 유전자 이입 전후, 암세포의 TNF에 대한 감수성 비교 TNF 유전자 이입 전후의 TNF에 대한 세포주의 감수성(세포사망율)을 TNF의 농도 변화에 따라 비교한 결과, NCI-H2058의 경우 TNF 농도 100ng/ml에서 모세포는 $25{\pm}3%$의 세포독성을 보인 반면 TNF 유전자 이입 후에는 $3{\pm}2%$의 세포독성을 보여 통계적으로 유의한 차이가 있었다(p<0.01). 그리고, WEHI-164의 경우도 TNF 농도 100ng/ml에서 모세포는 $73{\pm}5%$의 세포독성을 보인 반면 TNF 유전자 이입 후에는 $3{\pm}2%$의 세포독성을 보여 통계적으로 유의한 차이가 있었다(p<0.01). 결론 : TNF에 감수성을 보이는 암세포주인 NCI-H2058과 WEHI164에 TNF 유전자 이입을 시행하고 TNF가 발현되게 하였을 때, TNF 유전자를 이입받은 두 암세포주 모두에서 자신이 생산해 내는 TNF에 내성을 보여 생존하였다. 뿐만 아니라 생존한 이들 세포는 외부에서 준 TNF에 대해서도 내성을 보였다. 따라서, 암세포에 대한 TNF 유전자 이입을 통한 유전자 요법이 성공을 거두려면 유전자 이입된 세포에서 분비하는 TNF의 면역 세포 동원 방법 등의 간접적인 항암기전이 필요할 것으로 생각된다.

• 한국응급구조학회지
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• 제3권1호
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• pp.20-32
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• 1999

The purpose of this retrospective research of 603 patients who were transferred to the emergency medical center of university hospital from 1 Jan, 1998 to 31 Jan, 1998 was making of basic data for emergency medical transfer system improvement countermeasure and the point at issue of overlapping reexamination ststus of patients transfered to emergency medical center of university hospital from 1,2 level hospital. The data analysis was done by SPSS, t-test, ANOVA, Pearson correlation. The results were as follows: 1. Male to female ratio was 1.7:1 and peak age group was patients over forties and under nine years of age(70.5%) 2. Traumatic patients were 17.8%, motor vehicle accident patients were 16.7% and Non-traumatic patients were 65.3%. Transferring hospital was divided into 2groups: primary hospital, secondary hospital. The majority was secondary hospital(73.3%). The result of symptom severity classification of patients transferred to 3rd emergency medical center was urgent patients 32.5%, emergency patients 33.58%, non-emergency patients 34.0% 3. Most highest score items amoung overlapping reexamination of patients transfered to emergency medical center of university hospital from 1,2 level hospital were CBC test, simple X-ray (0.93점), CBC test(0.97점), urin test(0.88점), chemistry test(0.94점), simple X-ray(0.98점), CT(0.42점), EKG(0.89점) amoung overlapping reexamination of motor vehicle accident patients were more higher reexamination score than traumatic patients and non-traumatic patients 4. CBC test(P<0.001), urin test(P<0.001), chemistry test(P<0.001), simple X-ray(P<0.001), CT(P<0.01), EKG(P<0.001) amoung overlapping reexamination of patients in 2 level hospital were more higher reexamination score than 1 level hospital patients 5. About symptom severity classification of patients transferred to 3rd emergency medical center, CBC test(P<0.001), urin test(P<0.001), chemistry test(P<0.001), simple X-ray(P<0.01), CT(P<0.001), EKG(P<0.001) amoung overlapping reexamination items in urgent patients were more higher reexamination score than other patients 6. Influencing variation for overlapping reexamination in hospital was CBC test(P<0.001), CT (P<0.001), MRI (P<0.05).

• Journal of Trauma and Injury
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• 제24권2호
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• pp.118-124
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• 2011

Purpose: The incidence of multiple trauma is increasing nowadays and is the leading cause of death among young adults. Initial treatment is well known to be crucial in multiple trauma victims. However, many indiscriminate transfers occur due to the lack of a well-organized trauma system in Korea. The objective of this study is to demonstrate the current serious state in which major trauma patients are transferred to the Emergency Medical Center of a university hospital from another medical center. Methods: From November 2009 to October 2010, we performed a retrospective study to analyze the characteristics of patients who visited the Ajou University Medical Center located in Gyeonggi-do. We evaluated the ISS (injury severity score), and a score over 15 point was identified as major trauma. The major trauma patients were separated into two groups according to the visit route, and the characteristics of each group were analyzed. Results: Among the 88,862 patients who visited to the Emergency Medical Center, trauma patients accounted for 19,950, and 343 of them were evaluated as major trauma patients. Among the 343 patients, 170 patients had been transferred from other medical centers. The proportion of males to females was 3.3:1, and the mean ISS was 22.7. The leading cause of trauma was motor vehicle accidents. Of the total 170 patients, 77.6% were admitted to the Intensive care unit and 36.3% underwent surgery. The 170 patients that had been transferred to our medical center, 78.8% were transferred from Gyeonggi-do, 15.3% were transferred from other regions, and 5.9% were miscellaneous. Conclusion: Almost half of the major trauma victims treat at our medical center had been transferred from other medical centers. Establishing a traumatic system, supported by well-organized trauma centers and emergency medical services, that can reduce inappropriate transfers among medical facilities is essential.

• Asian-Australasian Journal of Animal Sciences
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• 제30권4호
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• pp.585-592
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• 2017

Objective: The present study investigates pre- and post-implantation developmental competence of nuclear-transferred porcine embryos derived from male and female fetal fibroblasts. Methods: Male and female fetal fibroblasts were transferred to in vitro-matured enucleated oocytes and in vitro and in vivo developmental competence of reconstructed embryos was investigated. And, a total of 6,789 female fibroblast nuclear-transferred embryos were surgically transferred into 41 surrogate gilts and 4,746 male fibroblast nuclear-transferred embryos were surgically transferred into 25 surrogate gilts. Results: The competence to develop into blastocysts was not significantly different between the sexes. The mean cell number of female and male cloned blastocysts obtained by in vivo culture ($143.8{\pm}10.5$ to $159.2{\pm}14.8$) was higher than that of in vitro culture of somatic cell nuclear transfer (SCNT) groups ($31.4{\pm}8.3$ to $33.4{\pm}11.1$). After embryo transfer, 5 pregnant gilts from each treatment delivered 15 female and 22 male piglets. The average birth weight of the cloned piglets, gestation length, and the postnatal survival rates were not significantly different (p<0.05) between sexes. Conclusion: The present study found that the sex difference of the nuclear donor does not affect the developmental rate of porcine SCNT embryos. Furthermore, postnatal survivability of the cloned piglets was not affected by the sex of the donor cell.

• 한국지반공학회논문집
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• 제31권10호
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• pp.49-60
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• 2015

기존 3차원 토압연구는 벽체에 작용하는 주동토압을 단일파괴체로 가정하고 벽체의 안정성에 초점을 맞춰 3차원 토압의 크기를 구하는데 역점을 두었고, 토압의 주변지반 전이에 대한 연구는 미진하였다. 따라서 본 연구에서는 벽체의 폭과 높이의 비 즉, 종횡비를 달리하여 3차원 모형실험을 수행하고, 주변지반으로 전이되는 토압의 크기와 영향범위를 파악하였다. 주변지반으로 전이되는 토압은 종횡비에 따라 3차원 주동토압의 감소량보다 17.9~30.6% 작게 나타났으며, 연직방향 토압의 전이보다 수평방향 토압의 전이가 크게 나타났다. 토압의 전이범위는 수평방향으로 주동벽체 폭 w 기준으로 0.67~1.29w, 연직방향으로 주동벽체 높이 ${\Delta}h$기준으로 약 1.0~3.0h인 것으로 나타났다. 수평방향으로 전이되는 토압은 종횡비가 같을 때 수평방향 모두 동일한 높이에서 최대치를 나타내며, 종횡비가 증가함에 따라 토압의 최대 전이 지점이 벽체 하부에서 상부로 변화하였다. 수평방향 토압의 전이는 주동벽체 폭 w 기준으로 0.25w에서 56%~79%인 것으로 나타났으며, 연직방향 토압의 전이는 주동벽체 ${\Delta}h$기준으로 1.0~1.5h에서 50%~58%인 것으로 나타났다. 종횡비에 따라 전이되는 토압의 크기와 영향범위를 분석하고 주동변위 벽체 주변으로 전달되는 3차원 하중전이 분포도를 제시하였다.

• 한국기록관리학회지
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• 제22권1호
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• pp.43-59
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• 2022

전자적으로 생산된 공공기록물은 생산과 동시에 편철되고 보존기간이 부여되며 일정기간이 지나면 영구기록물관리기관으로 이관되어 보존된다. 이관 시 기록물관리 담당자가 기록물 분류정보를 확인하고 품질을 일정 수준으로 유지토록 해야 하지만, 이관된 기록물의 분류는 기록물 정리/기술 업무로 편성되어 있고, 대부분의 정리/기술 업무는 수작업에 의존하고 있어 당해 연도에 처리해야 할 기록물 수량을 맞추기 어려운 실정이다. 이에 본 연구는 이관 기록물 분류 업무의 효율화와 일관된 기준을 유지하기 위한 방안을 제안하고자 한다. 이를 위해 먼저 국가기록원에서 수행하고 있는 현행의 기록분류 업무 프로세스를 분석하고 개선 요구사항을 수렴하여 분류 업무의 수작업을 최소화하기 위한 방안으로 이관된 기록물의 편철 정보, 즉 목록에 기반한 분류 이상치 후보를 판별하는 과정을 도출·체계화하였다. 나아가 제안한 이상치 판별 프로세스를 실제 국가기록원으로 이관된 기록물을 대상으로 적용하고, 그 결과를 규격화하여 추후 기계학습에 활용 가능한 학습데이터 형식으로 구축하였다. 본 연구의 궁극적인 목적은 지능형 전자기록 관리 환경 구축을 위한 사전 단계로, 기록관리 업무 내 기계학습 기법이 적용 가능한 문제 유형을 선별하고 자동화하는 방안을 모색하고자 한다.