• 한국컴퓨터정보학회논문지
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• 제28권12호
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• pp.221-229
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• 2023

최근 전력 계통에 인공 관성, 감쇠, 블랙스타트 기능, 독립 운전 기능 등을 제공할 수 있어 많은 주목을 받고 있는 Grid-forming(GFM) 컨버터는 저전압 Microgrids(MG)에서 낮은 라인 임피던스의 X/R 비율과 작지 않은 전력각으로 인한 유효전력과 무효전력 간의 커플링 현상이 발생한다. 이러한 전력 커플링 현상은 GFM 컨버터의 안정성 및 성능 저하 문제, 부정확한 전력 공유 문제, 제어 파라미터 설계 문제를 유발하고 있다. 따라서 본 논문은 GFM 컨버터와 관련된 제어 방법뿐만 아니라 전력 디커플링 방법에 대한 검토 연구로서, 유망 제어 방법을 소개하고 전력 디커플링 방법에 대한 비판적 검토를 통하여 향후 연구 활동의 접근성을 높이고자 하였다. 이에 따라 전력디커플링 방법 연구를 위해 향후 연구자들이 쉽게 접근할 수 있어 분산 발전원 확대에 기여할 수 있을 것이다.

• 한국가축번식학회지
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• 제9권2호
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• pp.140-147
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• 1985

Seventy four Holstein heifers were randomly assigned over three trials to PRID-7+PG-6 and Synchromate B-9 regimens to synchronize estrus cycle for embryo transfer. Sexual behaviors; moounting, standing, orientation, chin-resting, sniffing, licking, rubbing and butting, vaginal swelling and mucus discharge were observed between 06-08, 12-14 and 18-20 h on 1st day and 00-02, 06-08, 12-14 and 18-20 h on 2nd day after removal of hormones. Synchromate-B treatment (81.6%) showed higher synchronized estrus rate than PRID treatment (77.8%) during observation period. Standing estrus was observed within 74 h after PG injection in PRID and within 52 h after removal of implant in Synchromate-B. About 68% of heifers in PRID and 74% of heifers in Synchromate-B showed standing estrus between 0-14 h on 2nd day after removal of the hormones. Synchromate-B resulted in a tighter synchrony of standing estrus than PRID. Incidence of average mounting and standing per head during observation period was 22.3 and 16.6 in PRID and 28.1 and 13.6 in Synchromate-B. The PRID showed peak in active mounting at 18-20 h on 1st day, however, the Synchromate-B showed at 0-2 h on 2nd day after removal of hormone. Active standing was shown between 18 h on 1st day to 20h on 2nd day in PRID, however, between 0-14 h on 2nd day after removal of hormone is Synchromate-B. There was slight difference in pattern of active mounting and standing during estrus between PRID and Synchromate-B. Conception rate of synchronized heifers transferred with fresh and frozen embryos by non-surgical and surgical methods was higher in synchromate-B (62.5%) than in PRID (38.5%). Chin-resting showed highest incidence among 6 sexual behavioral components in the both treatments. Synchromate-B showed higher incidence of chin-resting (16.6) than PRID (10.7). Synchromate-B group showed also higher incidence of orientation, sniffing and butting than PRID group. Synchromate-B resulted in more active sexual behaviors than PRID. The pattern of incidence of chin-resting, licking and butting was almost symmetrical in PRID with their peak values at 6-8 h on 2nd day, however in Synchromate-B chin-resting and sniffing was symmetrical with their peak values at 12-14 h on 2nd day after removal of hormone. There was tendency to increase vaginal swelling according to time passage of synchronized estrus in the both treatments. Incidence of mucus discharge in Synchromate-B was slightly higher than in PRID. Twenty to 40% was false negative in conception rate by tall painting before re-estrus day as judged by rectal palpation.

• 대한약침학회지
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• 제19권4호
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• pp.359-362
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• 2016

Objectives: Loss of lumbar lordosis causing pain and curvature of the vertebral skeleton to one side is a relatively uncommon disease. To our knowledge, successful treatment of loss of lumbar lordosis with any potentized homeopathic drug diluted above Avogadro's limit (that is, above a potency of 12C) has not been documented so far. In this communication, we intend to document a relatively rare case of loss of lumbar lordosis with osteophytic lippings, disc desiccation, and protrusion, causing a narrowing of secondary spinal canal and a bilateral neural foramina, leading to vertebral column curvature with acute pain in an adolescent boy. Methods: The patient had undergone treatment with orthodox Western medicines, but did not get any relief from, or cure of, the ailment; finally, surgery was recommended. The patient's family brought the patient to the Khuda-Bukhsh Homeopathic Benevolent Foundation where a charitable clinic is run every Friday with the active participation of four qualified homeopathic doctors. A holistic method of homeopathic treatment was adopted by taking into consideration all symptoms and selecting the proper remedy by consulting the homeopathic repertory, mainly of Kent. Results: The symptoms were effectively treated with different potencies of a single homeopathic drug, Calcarea phos. X-ray and magnetic resonance imaging (MRI) supported recovery and a change in the skeletal curvature that was accompanied by removal of pain and other acute symptoms of the ailment. Conclusion: Homeopathy can be a safe, much less expensive, non-invasive, and viable alternative for the treatment of such cases.

• 생명과학회지
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• 제28권2호
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• pp.195-200
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• 2018

베타아사론은 널리 알려진 석창포의 주요 효능 성분이다. 본 연구에서는 모기의 oviposition 페로몬 성분인 MOP와 석창포 효능성분 베타아사론의 열대집모기 후각 단백질 CquiOBP1 활성 부위에 대한 친화도 분석 실험을 컴퓨터 분자결합 분석 방법을 통해 비교하였다. CquiOBP1 후각 단백질의 3차원 구조 정보는 PDB database (PDB ID: 3OGN)를 활용하였다. In silico 결합 분석을 수행하기 위해 PyRx, Autodock Vina, Discovery Studio Version 4.5, and NX-QuickPharm 프로그램을 각 분석 조건에 따라 활용하였다. CquiOBP1 후각단백질 활성 부위에 대한 베타아사론의 결합친화도는 -6.40 kcal/mol으로 나왔으며 이는 -6.00 kcal/mol으로 나온 MOP의 결합친화도 보다 훨씬 더 높고 효율적인 것으로 분석되었다. 리간드와 상호작용 하는 CquiOBP1단백질 활성 부위의 아미노산들 가운데 TRP114가 공히 MOP와 베타아사론과 결합 하였다. CquiOBP1 단백질 활성부위의 아미노산들을 전혀 다른 전기적 성질을 지닌 아미노산으로 치환 시킨 후 분자결합 분석을 해 본 결과 리간드들의 X,Y,Z Grid 값에 현격한 변화가 유도되었으며 결합 친화도 또한 감소되었다. 이러한 결과를 통하여 베타아사론은 CquiOBP1 단백질 활성을 조절하는 리간드로서 효과적으로 작용할 것으로 보인다. 결론적으로 석창포 추출물 또는 베타아사론은 곤충기피제 신물질 연구 개발 분야에 효율적으로 활용할 수 있을 것으로 사료된다.

• Tuberculosis and Respiratory Diseases
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• 제76권1호
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• pp.23-29
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• 2014

Background: Interferon-${\gamma}$ assays based on tuberculosis (TB)-specific antigens have been utilized for diagnosing and ruling out latent TB and active TB, but their utility is still limited for TB incidence countries. The aim of this study is to understand the clinical utility of enzyme-linked immunospot (ELISpot) assays among patients with clinically suspected TB and healthy adults in clinical practices and community-based settings. Methods: The ELISpot assays (T SPOT.TB, Oxford Immunotec, UK) were prospectively performed in 202 patients. After excluding those with indeterminate results, 196 were included for analysis: 41 were TB patients, 93 were non-TB patients, and 62 were healthy adults. Results: The sensitivity and negative predictive values of the T SPOT.TB assays for the diagnosis of TB were 87.8% and 89.1%, respectively, among patients with suspected TB. The agreement between the tuberculin skin test (10-mm cutoff) and the T SPOT.TB assay was 66.1% (kappa=0.335) in all participants and 80.0% (kappa=0.412) in TB patients. Among those without TB (n=155), a past history of TB and fibrotic TB scar on chest X-rays were significant factors that yielded positive T SPOT.TB results. There was a significant difference in the magnitude of T SPOT.TB spot counts between TB patients and non-TB patients or healthy adults. Conclusion: The T SPOT.TB assay appeared to be a useful test for the diagnostic exclusion of TB. A positive result, however, should be cautiously interpreted for potential positives among those without active TB in intermediate TB incidence areas.

• 한국결정성장학회지
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• 제19권2호
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• pp.61-65
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• 2009

본 논문에서는 형광체가 없는 백색 LED의 성장과 광학적인 특성을 분석하였다. 혼합소스(miked-source) HVPE(hydride vapor phase epitaxy) 방법과 다중성장보트를 이용하여 MOCVD로 얇게 성장한 n-GaN 위에 활성층을 AlGaN으로 한 이종접합구조(DH; Doublehetero structure)를 성장하고, 패키징 단계를 거쳐 비형광체 단일칩 백색 LED 램프를 제작하였다. 패키징 한 소자를 주입전류 $10{\sim}100mA$로 변화시켜 측정한 결과 색 연색성 값은 72-93, 색좌표의 좌표값은 X값은 $0.26{\sim}0.34$, Y값은 $0.31{\sim}0.40$에서 가지며, 색온도는 $5126{\sim}10406K$ 범위에서 측정되었다. 또한 주입전류 증가 시, 형광체를 사용한 백색 LED는 청색 영역으로 이동하지만, 제작된 백색 LED는 황색영역으로 색좌표가 이동하였다. 이러한 특성을 통하여 고감도의 색 연색성 값을 가지는 비형광체 백색LED의 성장 가능성을 확인하였으며, 광 특성 분석 결과를 통하여 혼합소스의 성장 메커니즘을 제안하고자 한다.

• 한국방사선학회논문지
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• 제12권3호
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• pp.381-387
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• 2018

본 실험은 비 전리방사선인 가시광선을 조사한 미생물에서의 생리적 대사특징을 연구하였다. 이 실험에 사용된 미생물은 화학합성미생물인 Phodospirillum Rubrum KS-301이었다. glucose의 회분발효를 수행하였고 발효결과는 테이터의 기초가 되었다. 첫째, 비 전리방사선인 가시광선을 조사를 안 할 때의 잔류 glucose(기질량)량을 5.03 g/L -2.17 g/L로 감소하면은 균체량은 1.08 g/L - 3.14 g/L로 수소생성량은 0.02 g - 0.19 g로 증가 하였다. 둘째, 비 전리방사선인 가시광선을 조사 할 때의 잔류 glucose(기질량)을 13.17 g/L - 5.2 g/L로 감소하면은 균체량은 4.7 g/L - 10.57 g/L로 수소생성량은 0.186 g - 0.3 g로 증가 하였다. 이 실험결과를 종합해 볼 때 비 전리방사선인 가시광선을 조사한 미생물에서의 생리적 대사특정으로는 가시광선을 미생물에게 조사한 결과 생명의 활동이 활발하게 일어나고 있음을 알았고 그 반대로 다양한 연구논문에 따르면 감마선, 엑스선, 전자선을 조사한 미생물에서는 세포치사나 세포의 기능적, 형태학적 장해를 나타내었음을 알 수가 있었다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVI)
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• pp.37-37
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• 2005

Human chorionic gonadotropin (hCG) is a heterodimeric glycoprotein hormone consisting of non-covalently linked two subunits, the ${\alpha}$ and ${\beta}$ subunit. It has been used as a infertility drug for ovulation to mimic luteinizing hormone $(LH).^{1)}$ A stable cell line was established by transfection of Rc/CMV-i-dhfr-hCG, expression vector containing hCG ${\alpha}-$ and ${\beta}-genes$, into dihydrofolate reductase-deficient CHO cells and subesquent methotrexate-mediated gene amplification. Anchorage-dependent CHO cells were adapted into a serum-free and/or animal component-free suspension medium through gradual serum weaning for the hCG production. The established cell line showed typical morphological characteristics and growth profile of CHO cells, and could produce FSH with passage-to-passage consistency. The high density perfusion culture of the CHO cells was carried out in Celligen Plus bioreactor equipped with a spin-filter as a internal cell retention device. The cell density reached up to $>1x10^{7}$ cells/ml in less than 7 days and a perfusion-control strategy based on cellular consumption rates of glucose was $established.^{2)}$ Biologically active recombinant hCG was purified by a series of chromatographic steps including anion exchange chromatography and hydrophobic interaction chromatography to homogeneity. The highly purified recombinant hCG was characterized for physicochemical, immunological and biological properties.

• 한국임상약학회지
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• 제25권3호
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• pp.138-144
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• 2015

Objective: It is to evaluate the drug interaction monitoring program as a pilot project to develop a pharmaceutical care model in a medical intensive care unit and to analyze the influencing factors of drug interactions. Method: Electronic medical records were retrospectively investigated for 116 patients who had been hospitalized in a medical intensive care unit from October to December in 2014. The prevalence of adverse reaction with risk rating higher than 'D' was investigated by Lexi-$Comp^{(R)}$ Online database. The factors related with potential drug interaction and with treatment outcomes were analyzed. Results: The number of patients with a potential interaction of drug combination was 92 (79.3%). Average ages, the length of stay in the intensive care unit and the numbers of prescription drugs showed significant differences between drug interaction group and non-drug interaction group. Opioids (14.4%), antibiotics (7.2%), and diuretics (7.2%) were most responsible drug classes for drug interactions and the individual medications included furosemide (6.4%), tramadol (4.9%), and remifentanil (4.5%). There were 950 cases with a risk rating of 'C' (84.6%), 142 cases with a risk rating of 'D' (12.6%), and 31 cases with a risk rating of 'X' (avoid combination) (2.8%). The factors affecting drug interactions were the number of drugs prescribed (p < 0.0001) and the length of stay at intensive care unit (p < 0.01). The patients in intensive care unit showed a high incidence of adverse reactions related to potential drug interaction. Therefore, drug interaction monitoring program as a one of pharmaceutical care services was successfully piloted and it showed to prevent adverse reaction and to improve therapeutic outcomes. Conclusion: Active participation of a pharmacist in the drug management at the intensive care unit should be considered.

• The Korean Journal of Physiology and Pharmacology
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• 제21권6호
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• pp.599-607
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• 2017

Most normal cells express L-type amino acid transporter 2 (LAT2). However, L-type amino acid transporter 1 (LAT1) is highly expressed in many tumor cells and presumed to support their increased growth and proliferation. This study examined the effects of JPH203, a selective LAT1 inhibitor, on cell growth and its mechanism for cell death in Saos2 human osteosarcoma cells. FOB human osteoblastic cells and Saos2 cells expressed LAT1 and LAT2 together with their associating protein 4F2 heavy chain, but the expression of LAT2 in the Saos2 cells was especially weak. JPH203 and BCH, a non-selective L-type amino acid transporter inhibitor, potently inhibited L-leucine uptake in Saos2 cells. As expected, the intrinsic ability of JPH203 to inhibit L-leucine uptake was far more efficient than that of BCH in Saos2 cells. Likewise, JPH203 and BCH inhibited Saos2 cell growth with JPH203 being superior to BCH in this regard. Furthermore, JPH203 increased apoptosis rates and formed DNA ladder in Saos2 cells. Moreover, JPH203 activated the mitochondria-dependent apoptotic signaling pathway by upregulating pro-apoptotic factors, such as Bad, Bax, and Bak, and the active form of caspase-9, and downregulating anti-apoptotic factors, such as Bcl-2 and Bcl-xL. These results suggest that the inhibition of LAT1 activity via JPH203, which may act as a potential novel anti-cancer agent, leads to apoptosis mediated by the mitochondria-dependent intrinsic apoptotic signaling pathway by inducing the intracellular depletion of neutral amino acids essential for cell growth in Saos2 human osteosarcoma cells.