• Journal of the Korea Society of Computer and Information
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• v.28 no.12
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• pp.221-229
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• 2023

Recently, Grid-forming(GFM) converter, which offers features such as virtual inertia, damping, black start capability, and islanded mode operation in power systems, has gained significant attention. However, in low-voltage microgrids(MG), it faces challenges due to the coupling phenomenon between active and reactive power caused by the low line impedance X/R ratio and a non-negligible power angle. This power coupling issue leads to stability and performance degradation, inaccurate power sharing, and control parameter design problems for GFM converters. Therefore, this paper serves as a review study on not only control methods associated with GFM converters but also power decoupling techniques. The aim is to introduce promising control methods and enhance accessibility to future research activities by providing a critical review of power decoupling methods. Consequently, by facilitating easy access for future researchers to the study of power decoupling methods, this work is expected to contribute to the expansion of distributed power generation.

• Korean Journal of Animal Reproduction
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• v.9 no.2
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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.

• Journal of Pharmacopuncture
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• v.19 no.4
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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.

• Journal of Life Science
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• v.28 no.2
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• pp.195-200
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• 2018

Beta-asarone is the well-known active ingredient of Rhizoma acori graminei. In this study, we investigated and compared the binding affinity of mosquito oviposition pheromone (MOP; (5R,6S)-6-acetoxy-5-hexadecanolide) and beta-asarone on the A domain of the mosquito odorant binding protein 1 (CquiOBP1) by in silico computational docking studies. The three-dimensional crystallographic structure of CquiOBP1 was obtained from the PDB database (PDB ID: 3OGN). In silico computational auto-docking analysis was performed using PyRx, Autodock Vina, Discovery Studio Version 4.5, and the NX-QuickPharm option based on scoring functions. The beta-asarone showed optimum binding affinity (docking energy) with CquiOBP1 as -6.40 kcal/mol as compared to the MOP (-6.00 kcal/mol). Among the interacting amino acids (LEU76, LEU80, ALA88, MET89, HIS111, TRP114, and TYR122), tryptophan 114 in the CquiOBP1 active site significantly interacted with both MOP and beta-asarone. Amino acids substitution (mutation) from non-polar groups to the polar (or charged) groups of the CquiOBP1 dramatically changed the X, Y, Z grid position and binding affinity of both ligands. These results significantly indicated that beta-asarone could be a more potent ligand to the CquiOBP1 than MOP. Therefore, the extract of Rhizoma acori graminei or beta-asarone can be applied to the fields of insecticidal and repellant biomaterial development.

• Tuberculosis and Respiratory Diseases
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• v.76 no.1
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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.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.19 no.2
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• pp.61-65
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• 2009

In this paper, we report on the growth and optical characteristics of white-LED without fluorescent material. The growth of DH(double heterostructure) with AlGaN active layer was performed on a n-GaN/(0001) $Al_{2}O_{3}$ by the mixed-source HVPE and multi-sliding boat. The CRI(color rendering index) of packaging device charged in the range 72-93 with CIE chromaticity coordinates(x=$0.26{\sim}0.34$, y=$0.31{\sim}0.40$). And CCT(correlated color temperature) values was measured $5126{\sim}10406K$ with increasing injection current. The CIE point of conventional phosphor white LED shifts blue region, but cm point of non-phosphor white LED shifts opposite direction. These results show the mixed-source HVPE can be possible to newly fabricate method of phosphor free white LED with high CRI value.

• Journal of the Korean Society of Radiology
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• v.12 no.3
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• pp.381-387
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• 2018

A Effect on physiological metabolism of microorganism which irradiated by visible light of non-ionization radiation(12,000 Lux) was investigated. The microorganism used in this experiment was a Rhodospirillum rubrum KS-301 of chemosynthetic microorganism. Batch fermentation of glucose were implement, and based on the data resulted from the fermentation. First, physiological characteristic of microorganism which was not irradiated was investigated. As a result, the decrease of the residual quantity of the substance(5.03 g/L - 2.17 g/L) was increased with the quantity of the bacteria(1.08 g/L - 3.14 g/L)and the quantity of the hydrogenous production(0.186 g - 0.3 g) respectively. Second, physiological characteristic of microorganism which was irradiated was investigated. As a result, the decrease of the residual quantity of the substance(13.17 g/L - 5.2 g/L) was increased with the quantity of the bacteria(4.7 g/L - 10.57 g/L)and the quantity of the hydrogenous production(0.186 g - 0.3 g) respectively. As the physiological characteristic of microorganism which was irradiated by visible light of non-ionization radiation(12,000 Lux) was active with its life, but the cell damages irradiated by with gamma-ray, X-ray, electron-ray in ionization radiation were appeared at cell.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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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.

• Korean Journal of Clinical Pharmacy
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• v.25 no.3
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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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• v.21 no.6
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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.