• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.11a
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• pp.1027-1028
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• 2010

• Proceedings of the KIEE Conference
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• 1994.07a
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• pp.12-14
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• 1994

In industrial drive of the BDCW motor, voltage source inverter is of tenly used. In this paper in operation of the inverter for the BDCM drives, some PWM techniques are applied and the mathematical torque ripple model is developed to investigate the performance of the PWM techniques. The simulation results show that the multiple pulse modulation is practically introduces the lowest torque ripple components.

• Bulletin of the Korean Space Science Society
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• 2009.04a
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• pp.56.4-56.4
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• 2009

• Journal of Microbiology and Biotechnology
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• v.29 no.4
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• pp.633-644
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• 2019

An advanced anaerobic expanded granular sludge bed (AnaEG) and an internal circulation (IC) reactor, which were adopted to treat starch processing wastewater (SPW) and ethanol processing wastewater (EPW), were comprehensively analyzed to determine the key factors that affected the granules and microbial communities in the bioreactors. The granule size of $900{\mu}m$ in the AnaEG reactor was smaller than that in the IC reactor, and the internal and external morphological structures of the granular sludge were also significantly different between the two types of reactors. The biodiversity, which was higher in the AnaEG reactor, was mainly affected by reactor type. However, the specific microbial community structure was determined by the type of wastewater. Furthermore, the dominant methanogens of EPW were mainly Methanosaeta and Methanobacterium, but only Methanosaeta was a major constituent in SPW. Compared with the IC reactor, characteristics common to the AnaEG reactor were smaller granules, higher biodiversity and larger proportion of unknown species. The comparison of characteristics between these two reactors not only aids in understanding the novel AnaEG reactor type, but also elucidates the effects of reactor type and wastewater type on the microbial community and sludge structure. This information would be helpful in the application of the novel AnaEG reactor.

• Clinical and Experimental Pediatrics
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• v.51 no.11
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• pp.1217-1221
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• 2008

Purpose : An association between idiopathic thrombocytopenic purpura (ITP) and systemic lupus erythematosus (SLE) has been recognized for decades because thrombocytopenia is the first manifestation in some patients with SLE. However, the risk of later development of SLE in childhood ITP is currently unknown. We retrospectively evaluated the incidence and clinical significance of the positive antinuclear antibody (ANA) in children with acute ITP. Methods : This study was retrospectively performed to review the clinical and laboratory characteristics in 77 children diagnosed to have acute ITP and admitted to the Pusan National University Hospital between January 2003 and December 2006. Patients tested positive for ANA were regularly followed-up for at least 12 months for symptoms indicative of SLE. Results : Seventy-seven children were included in the study; 38 males (49.4%) and 39 females (50.5%), the mean age was 4.5 years. Sixteen (20.8%) ITP patients had a positive ANA, with a median titer of 1:320. The mean age of the patients with positive ANA was 9.3 years, which is much older than 3.3 years for patients with negative ANA (P<0.05). The positive ANA group was predominantly female (81.3%) compared to the negative ANA group (P<0.05). There was no statistically significant difference in mean platelet counts between both groups. No statistically significant difference was found in ANA positivity and progression to chronic ITP or SLE. After the median follow-up of 32 months, SLE was diagnosed only in one ITP patient with positive ANA. Conclusion : Our data demonstrated that ANA positivity is often found in children with acute ITP. Large-scale studies should be considered to determine the significance of ANA positivity in childhood ITP for the later development of SLE.

• Weed & Turfgrass Science
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• v.5 no.3
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• pp.136-143
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• 2016

This study was conducted to investigate the algicidal characteristics of cashew nut oil (CNO) and to develop CNO mixtures with other compounds having synergistic effects on the growth inhibition against a blue-green alga, Microcystis aeruginosa. Among tested CNOs, CNO with higher anacardic acid contents (Ana-A) exhibited the best algicidal activity against M. aeruginosa. Ana-A showed broad algicidal spectrum with particular greater activity against blue-green algae than green algae. Ana-A showed the greatest activity against to Oscillatoria tenuis ($IC_{50}=0.19{\mu}g\;mL^{-1}$) among the tested blue-green algae and to Chlorella vulgaris ($IC_{50}=4.54{\mu}g\;mL^{-1}$) among the tested green algae, respectively. In a mixture experiment to evaluate a chemical interaction in M. aeruginosa control, Ana-A showed a strong synergistic effect with MSB and menadione, mild synergistic effect with citric acid, and additive effect with chryspophanol, copper sulfate and quinoclamine. Taken together, our results suggest that CNO containing higher anacardic acid can be used as an eco-friendly natural algicide for selective control of blue-green algae such as M. aeruginosa and O. tenuis through an optimization of application rate and in combination with synergists such as MSB and menadione.

• Journal of Cardiovascular Imaging
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• v.31 no.4
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• pp.209-210
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• 2023

• Proceedings of the KIEE Conference
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• 1991.11a
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• pp.223-226
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• 1991

In this paper, the problem of designing on adaptive controller for dc drives using state observers, which is operated under varying load conditions, is addressed. A robust self-tuning controller that can track a constant reference and reject constant load disturbances is also studied. This scheme is very attractive since the estimates of system parameters are available in real time. Parameter estimation is based on the recursive least squares method and the control algorithm of the pole placement technique. Also, state observer systems are applied. State observer systems are required to estimate the states quickly and exactly without being affected by the disturbances.

• Language and Information
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• v.4 no.1
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• pp.83-96
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• 2000

In thihs paper, I investigate the different usage of a reflexive-anaphor or logophor. Some African languages which have a morphologically independent set of logophors give a clue to this dichotomy. English which does not have morphologically independent logophors employs a reflexive-self form to be used as a logophor. However, the logophors in English occur in restricted environments. On the other hand, Korean is freer than English in that it allows areflexive to be interchanged with a logophor. With this assumption, I deal with the binding in Optimality Theory. I set up the constraints-MAXlog,ana,MINlog,ana, and Ølog,ana. With these constraints, the binding in various languages are explained through constraint ranking. In addition, the long-distance binding in English is dealt with properly of we assume the dichotomy and constraint-ranking in Optimality Theory. Furthermore, this gives an explanation to reflexive and pronoun alternation in English. Also, I borrow from phonology the idea of Obligatory Contour Principle to explain the similar phenomenon in syntax. I compare English with Korean in dealing with the possessive reflexive with the recourse to The Emergence of the Unmarked Pronoun Bresnan 1997. Fnmally, the reconstruction phenomenon is accounted for with the same device.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.10a
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• pp.68-76
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• 2004

It is essential to develop a transient engine system analysis model for turbopump fed type liquid rocket engine development, especially for deriving engine system test number and conditions. In this study, we proposed a mathematical model of turbopump fed type liquid rocket engine, and inspected transient mode changes around the nominal thrust level of a rocket engine according to variations of trust control valve's opening ratio. To verify the results, we solved the same problem with AnaSyn software from Russia, and concluded that the transient code showed the similar results within $2\%$ with AnaSyn.