• Proceedings of the KIEE Conference
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• 1994.07a
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• pp.559-561
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• 1994

In this paper a new AC/DC/AC converter in which Soft-Switched-Inductor Module is used, is proposed. This new converter adopts ZVS(Zero-Voltage-Switching) for main switches. Therefore the switching loss is minimized and high frequency operation is possible. Operations principles, short analyses and computer simulation results are presented.

• Communications of the Korean Mathematical Society
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• v.21 no.2
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• pp.211-217
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• 2006

Topos is a set-like category. In topos, the axiom of choice can be expressed as (AC1), (AC2) and (AC3). Category Fuz of fuzzy sets has a similar function to the topos Set and it forms weak topos. But Fuz does not satisfy (AC1), (AC2) and (AC3). So we define (WAC1), (WAC2) and (WAC3) in weak topos Fuz. And we show that they are equivalent in Fuz.

• BMB Reports
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• v.38 no.1
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• pp.49-57
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• 2005

Major Royal Jelly Protein cDNAs of Apis cerana (AcMRJP) were cloned and characterized. The open reading frames (ORFs) of the AcMRJP1 and AcMRJP2 genes were 1302 and 1392 nucleotides, encoding 433 and 463 amino acid residues, respectively. The sequence divergences between AcMRJP1 and AcMRJP2 and their corresponding protein families in A. mellifera were 0.0618 and 0.0934 at the nucleotide level and 0.0912 and 0.1438 at the protein level, respectively. Phylogenetic analysis supports the orthologous similarity between these proteins. The deduced amino acids indicated high essential amino acid contents of AcMRJP1 and AcMRJP2 (47.5 and 44.8%, respectively). The genomic organization of both AcMRJP1 and AcMRJP2 was determined. Both the AcMRJP1 (3663 bp) and AcMRJP2 (3963 bp) genes contained six exons and five introns, where all boundaries conformed to the GT/AG rule. AcMRJP1 and AcMRJP2 cDNAs were cloned into pET17b, and both the recombinant (r) AcMRJP1 (47.9 kDa) and rAcMRJP2 (51.7 kDa) were expressed in the insoluble form. Western blot analysis and N-terminal sequencing of the solubilized proteins revealed successful expression of rAcMRJP1 and rAcMRJP2 in vitro. The yields of the purified rAcMRJP1 and rAcMRJP2 were approximately 20 and 8mg protein per liter of the flask culture, respectively.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.5B no.2
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• pp.181-188
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• 2005

In this paper, a DC smoothing filterless soft switching pulse modulated high frequency AC power conversion circuit connected to utility. frequency AC power source is proposed for consumer induction heating hot water producer, steamer and super heated steamer. The operating principle of DC link filterless utility frequency AC-high frequency AC (HF AC) power conversion circuit defined as high frequency cycloinverter is described, which can operate under a principle of ZVS/AVT and power regulation based on alternate asymmetrical PWM in synchronization with the utility frequency single phase AC positive or negative half wave voltage. The dual mode modulation control scheme based on high frequency PWM and commercial frequency AC voltage PDM for the proposed high frequency cycloinverter are discussed to enlarge its soft switching commutation operating range for wide HF AC power regulation. This high frequency cycloinverter is developed for high frequency IH Dual Packs Heater (DPH) type boiler used in consumer and industrial fluid pipeline systems. Based on the experiment and simulation results, this high frequency cycloinverter is proved to be suitable for the consumer use IH-DPH boiler and hot water producers. The cycloinverter power regulation and power conversion efficiency characteristics are evaluated and discussed.

• Biomolecules & Therapeutics
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• v.31 no.6
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• pp.611-618
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• 2023

Rhizome of Alisma orientale has been used as a traditional medicine for treating kidney diseases in East Asian countries. Its inhibitory effects on hypersensitivity responses have been reported for methanol extracts, with alisol B 23-acetate (AB23Ac) being the most active constituent among six terpenes in inhibiting the direct passive Arthus reaction. However, whether AB23Ac has efficacy against allergic asthma has not been tested to date. The in vivo efficacy of AB23Ac in an ovalbumin (OVA)-induced allergic asthma mouse model was evaluated by administrating AB23Ac before OVA sensitization or OVA challenge in BALB/c mice. AB23Ac suppressed antigen-induced degranulation of RBL-2H3 mast cells in a concentration-dependent manner. The administration of AB23Ac both before OVA sensitization and OVA challenge greatly lowered pulmonary resistance and the increase in immune cell counts and inflammatory responses around the peribronchial and perivascular regions. In addition, the inflammatory cytokine levels of Th1/Th2/Th17 cells in the bronchoalveolar lavage fluid decreased in the AB23Ac-treated groups. AB23Ac reduced the number of PAS-stained cells in the lungs. Furthermore, a computer modeling study indicated that AB23Ac can bind tightly to spleen tyrosine kinase (Syk). These results suggest that AB23Ac may ameliorate allergic asthma by suppressing immune responses in dendritic cells during sensitization and in mast cells during challenge periods.

• The Transactions of the Korean Institute of Power Electronics
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• v.7 no.3
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• pp.244-252
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• 2002

In this paper, do link ripple currents for three-phase ac/dc/ac PWM converters feeding adjustable speed ac machine drives are analysed in a frequency domain. The expression of the harmonic currents is developed by using switching functions of the converter and exponential courier series expansion. The effect of the displacement angle between the switching Periods of line-side converters and motor-side inverters on the dc link ripple currents is Investigated. Also, the influence of asynchronization of PWM is observed. The result of analysis is compared with frequency spectrum which results from PSIM simulation. The proposed analysis technique is useful to understand the principles of P% and to derive an equivalent model of the dc link capacitors in a high frequency range.

• Journal of Environmental Science International
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• v.22 no.2
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• pp.205-213
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• 2013

This is made of domestic and foreign coal activated carbon of five species, physicochemical adsorption efficient about sterilize products and micro harmful substances and is a result of the economic evaluation. The most well-developed micropores bed volume 123,409 of AC-1 activate carbon appeared to be the best next AC-2, AC-3, AC-4, AC-5 followed by activated carbon was investigated. PFOA and PFOS in the BV 96,000 when evaluating foreign types of adsorption activated carbon adsorption capacity was greater when more than PFOA, PFOS showed that the adsorption well. The economic evaluation of activated carbon usage in chloroform (CUR) was most excellent as a AC-1 4.3 g/day, the next AC-2, AC-3, AC-4, AC-5 there are two types of foreign economic order appears to have appeared, but the current domestic market when applying the price AC-1, AC-3, AC-2, AC-4, AC-5 order was investigated.

• International Neurourology Journal
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• v.22 no.4
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• pp.287-294
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• 2018

Purpose: Augmentation cystoplasty (AC) is a surgical procedure used in adults and children with refractory bladder dysfunction, including a small bladder capacity and inadequate bladder compliance, and in whom conservative and medical treatment has failed. This study was aimed to determine the long-term outcomes of AC in children. Methods: A retrospective analysis was conducted of 42 patients (31 males; mean age, $14.2{\pm}6.2years$) who underwent AC for neurogenic and nonneurogenic bladder dysfunction, with a median $12.0{\pm}1.5years$ of follow-up. All patients underwent AC using the ileum with or without continent reconstruction. Pre-AC, concurrent, and post-AC procedures and complications were analyzed. Patients who underwent ureterocystoplasty, were lost to follow-up, or had less than 10 years of follow-up were excluded. The primary outcomes were the complication and continence rates, the post-AC linear rate of height and weight gain, and renal function. The Student t-test was used to evaluate between-group differences and the paired t-test was used to evaluate longitudinal changes in measured variables. Results: Renal function was stable or improved in 32 of 42 patients (76.2%), with a post-AC continence rate of 88.1%. Thirty patients (71.4%) required 72 procedures post-AC. There was no statistically significant difference in the mean percentile of height (P=0. 212) or weight (P=0.142) of patients in the pre- and post-AC periods. No cases of bladder perforation or malignancy were detected. Conclusions: We consider AC to be a safe and effective procedure that does not negatively affect future physical growth, while achieving a good rate of stable renal function. Patients need long-term follow-up to address long-term complications.

• Korean Journal of Plant Resources
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• v.31 no.6
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• pp.634-640
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• 2018

Aralia cordata (A. cordata), which belongs to Araliaceae, is a perennial herb widely distributed in East Asia. We evaluated the anti-inflammatory effect of stems (AC-S), roots (AC-R) and leaves (AC-L) extracted with 100% methanol of A. cordata and elucidated the potential signaling pathway in LPS-stimulated RAW264.7 cells. The AC-L showed a strong anti-inflammatory activity through inhibition of NO production. AC-L dose-dependently inhibited NO production by suppressing iNOS, COX-2 and $IL-{\beta}$ expression in LPS-stimulated RAW264.7 cells. AC-L inhibited the degradation and phosphorylation of $I{\kappa}B-{\alpha}$, which donated to the inhibition of p65 nuclear accumulation and $NF-{\kappa}B$ activation. Furthermore, AC-L suppressed the phosphorylation of ERK1/2 and p38. These results suggested that AC-L may utilize anti-inflammatory activity by blocking $NF-{\kappa}B$ and MAPK signaling pathway and indicated that the AC-L can be used as a natural anti-inflammatory drugs.

• Journal of the Korean Chemical Society
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• v.8 no.3
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• pp.103-108
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• 1964

A rapid method of daughter free Ac$^{227}$ tracer preparation was studied. Through two stage extraction by HDEHP and TBPO, essentially daughter free Ac$^{227}$ tracer can be prepared. Possible loss of Ac$^{227}$ activity during the process was estimated. Milking of Th$^{227}$ from Ac$^{227}$ was also studied.