• Korean Journal of Microbiology
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• v.26 no.3
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• pp.215-222
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• 1988

The effect of ammonia and glutamine on nitrogenase activity of Rhodopseudomonas sphaeroides was examined. The nitrogenase activity of this strain was inhibited by ammonia and glutamine. When ammonia and glutamine were exhausted, nitrogenase activity promptly resumed at its original rate. Methionine sulfoximine (MSX), irreversible glutamine synthetase (GS) inhibitor, is a structural analogue of glutamate. MSX was used in order to know whether the nitrogenase activity was inhibited by ammonia and glutamine directly or not. The ability of MSX to prevent nitrogenase switch-off by ammonia was found to be dependent upon the phase of culture. When the cells were sampled after 12 hour culture, $500{\mu}M$ MSX would not prevent the nitrogenase switch-off by ammonia. Twenty one percents of GS actibity was inhibited by $500{\mu}M$ of MSX and concentration of released ammonia decreased. But nitrogenase activiy was still inhibited by ammonia. However, nitrogenase switch-off after 20 hours would be prevented by $100{\mu}M$ of MSX. On the other hand, GS activity was ingibited completely by $100{\mu}M$ MSX and concentration of released ammonia somewhat increased. But nitrogenase activity was not inhibited. The data indicated that the inhibition of in vivo nitrogenase actibity of Rp. sphaeroides by ammonia seemed to be mediated by products of ammonia assimilation rather than by ammonia itself.

• Clean Technology
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• v.18 no.4
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• pp.404-409
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• 2012

In this study, the effects of mixing intensity and coagulant dosages on the characteristics of floc growth for phosphorus removal were investigated. The experiments were conducted under Al/P molar ratio of 1.0, 1.5 and 2.0; rapid mixing intensity with G value of 100, 300, and 500 $s^{-1}$. The characteristics of floc growth were measured by flocculation index (FSI) and the removal efficiencies of phosphorus by using different size filters. The removal efficiencies of soluble phosphorus increased as Al/P molar ratio and rapid mixing intensity increased. However, the highest removal efficiencies of T-P were observed at G value of 300 $s^{-1}$. When Al/P molar ratio was lower than 1.0, the value of FSI at G value of 500 $s^{-1}$ was the largest. However, when Al/P ratio was larger than 1.0, the value of FSI at G value 300 $s^{-1}$ was the largest. Effects of mixing intensity and Al/P molar ratio on coagulation for phosphorus removal of synthetic and real wastewater effluent were observed to be similar.

• International Commerce and Information Review
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• v.11 no.3
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• pp.287-309
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• 2009

There were many changes regarding Negotiation of document under UCP 600. First of all, the definition of Negotiation was changed. The UCP 500 stated "Negotiation means the giving of value for drafts and documents by the bank authorized to negotiation", but the UCP 600 defines "negotiation" as following "negotiation means the purchase by the nominated bank of drafts and/or documents under a complying presentation". Under the UCP 600 the meaning of negotiation was more clear than UCP 500. Second UCP 600 permits all deferred payment credits be discountable or negotiable. This amended rule equated the deferred payment credit with banker's acceptance credit which was contrary with the nature and the practice of former deferred payment credit transaction. Third, UCP 600 has also provided for reimbursement rights for nominated banks and a conceptual basis for protecting nominated banks against beneficiary fraud. In this paper, the problems regarding negotiation of document under UCP600 was studied and the solutions for the problems occurring in appling UCP 600 in practical field was provided.

• The KSFM Journal of Fluid Machinery
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• v.5 no.4 s.17
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• pp.32-39
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• 2002

The purpose of this 3-D numerical simulation is to calculate and examine the complex 3-D stall phenomena on the rotor blade and wake distribution of the wind turbine. The flow characteristics of 500kW Horizontal Axis Wind Turbine (HAWT) are compared with the calculated 3-D stall phenomena and wake distribution. We used the CFX-TASCflow to predict flow and power characteristics of the wind turbine. The CFD results are somewhat consistent with the BEM (Blade Element Momentum) results. And, the rotational speed becomes faster, the 3-D stall region becomes smaller. Moreover, the pressure distribution on the pressure side that directly gets the incoming wind grows high as it goes toward the tip of the blade. The pressure distribution on the blade's suction side tells us that the pressure becomes low in the leading edge of the airfoil as it moves from the hub to the tip. However, we are not able to precisely predict on the power coefficient of the rotor blade at the position of generating complex 3-D stall region.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1001-1006
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• 2005

A Robot Performance Evaluation System(RPES) with the laser tracker Leica LTD 500 was developed according to the ISO 9283 robot performance criteria. The developed system is set up a test robot to continuously move the prescribed cyclic trajectories without a human intervention and the laser tracker to simultaneously measure the robot's movement. And then, the system automatically extracts the required data from the tremendous measured data, and computes the various performance criteria which represents the present state of the test robot's performance. This paper explains how ISO 9283 robot performance criteria was used for the developed system, and suggests a automatic data extraction algorithm from the mass of measured data. And also, a user-friendly Robot Performance Evaluation System(RPES) Software was developed with Visual Basic satisfying the need of Hyundai Motor Company. The developed system was implemented on NACHI 8608 AM 11 robot. The resulted output shows the effectiveness of the developed system.

• Korean Journal of Microbiology
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• v.34 no.3
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• pp.115-119
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• 1998

We cloned the 4.8 kb BglII fragment containing genes downstream pHENX7 from Pseudomonas sp. strain DJ77. The restriction map of the resultant clone, recombinant plasmid pYCS500, was determined. Sequencing analysis of the 465 bp HindIII-ClaI fragment revealed an open reading frame of 282 bp that was then designated phnM. The deduced polypeptide is 93 amino acid residues long with a $M_r$ of 10,008. The PhnM has 37.3-53.9% identity with plant-type ferredoxin proteins such as NahT, XylT, DmpQ, AtdS, PhlG, PhhQ and TbuW and contains the motif similar to well-conserved functional domains of those proteins.

• Food Science and Preservation
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• v.10 no.3
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• pp.417-420
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• 2003

In order to study optimum culture condition of yeast medium added deep seawater, we examed samples with 9 yeast strains. The growth rate were measured for Saccharomyces cerevisiae 10, 11, 12, 901 and RCY and Saccharomyces kluyvery DJ97, Saccharomyces cerevisiae YJK, JK99, CMY-28 etc.. The growth of S. cerevisiae 12 was found most active in the deep seawater(hardness 500). The growth rate of S. cerevisiae 901 on medium containing deep seawater(hardness 1000) was faster than that of the yeast on medium without deep seawater. The use of deep seawater on the growth of Sacch.cerevisiae kluyvery DJ97 revealed maximum growth under the condition of hardness 200 of deep seawater and 10％ of sugar concentration.

• Journal of Korean Medicine Rehabilitation
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• v.28 no.2
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• pp.37-45
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• 2018

Objectives This study was designed to investigate whether the Gagamtongsoon-San (GT) has an inhibitory effect and its mechanisms are associated with the iNOS and COX-2. Methods Cytotoxic activity of GT extract on RAW264.7 cells was evaluated by using 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) solution. Inflammatory condition was induced by LPS. NO production was measured using Griess reagent system. The expressions of iNOS and COX-2 mRNA and protein were determined by realtime PCR. The concentrations of PGE2 were measured by an enzyme immunoassay (EIA). Results The GT does not impair the cell viability in tested concentration $500{\mu}g/ml$ or below. GT significantly reduced the NO production in a dose-dependent manner. GT $500{\mu}g/ml$ also suppressed LPS-induced mRNA expressions of iNOS and COX-2. GT $500{\mu}g/ml$ reduced the PGE2 secretion in LPS induced RAW264.7 cells. Conclusions These outcomes show that GT extract has an anti-inflammatory activities. And also this conclusion can be the data that supports the GT's anti-inflammatory effect objectively.

• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.749-752
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• 1993

This paper deals with the development of three phase 440[V], 500[KVA] Inverter system using the IGBT Devices. IGBT's have been used very successfully in variable frequency induction motor drive equipment. Problems associated with power devices characteristics when power devices are operated in parallel, such as balanced switching behavior and thermal stability, can be solved by using NPT type IGBT's. By Experimental results, it is confirmed that the voltage overshoot and reverse recovery current was very low. The equipment had proved to be reliable and short circuit proof. In addition, the performances in term of thermal characteristics, protection functions and stability are satisfactory.

• Vending industry
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• v.8 no.3
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• pp.115-115
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• 2008