• Proceedings of the KIPE Conference
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• 2011.11a
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• pp.153-154
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• 2011

본 논문은 비대칭 2상 SRM의 센서리스 속도제어를 위한 초기각 검출 및 초기 기동방식과 자속관측기를 적용한 센서리스 제어에서 전동기의 온도 및 파라미터 변동에 의한 자속 오차 성분으로 인해 발생하는 위치 추정오차를 보상하기 위한 새로운 보상기를 제안한다. 제안된 방식은 전압펄스 인가로 초기각을 검출하고 검출된 초기 위치정보를 바탕으로 동일한 전압펄스 인가를 통해 비여자상이 여자상이 되는 회전자 위치를 검출하여 상여자를 교체하는 초기기동을 통해 자속관측기를 적용한 센서리스 제어로 안정적으로 진입하도록 한다. 이 때, 제안된 추정위치 보상기를 통해 추정된 센서리스 위치를 순시적으로 보상한다.

• Proceedings of the KIEE Conference
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• 1991.11a
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• pp.133-136
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• 1991

New phase-energization strategies are proposed to minimize torque ripple of closed-loop controlled 2-phase Bifilar Hybrid step motors. Lead angle and conduction angles are important parameters in minimizing torque ripple factors. The phase-energization control strategy that minimizes torque ripples for the given average torque is proposed. In this paper, Fourier series are applied to produce the average torque. The strategy is performed by controlling both lead angle and conduction angle of the input voltage wave-form for each phase.

• Journal of Korean Society of Water and Wastewater
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• v.22 no.1
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• pp.169-174
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• 2008

In this study a trickling filter system was developed by using polypropylene media and polypropylene nylon media that has recently been developed. The experiment analyzed an ability of water purification of the two plastic media and the effects of biomass on the final effluent. As recycling ratio increases, polypropylene nylon suspender showed higher efficiency by 20%; and, when media height was lengthened twice, efficiency increased about 10%. EPS and biomass increased in proportion to the increase of recycling ratio, and bound-TOC showed a similar trend with bound-EPS (extra-cellular polymeric substances) concentration.

• Journal of Korean Society of Water and Wastewater
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• v.23 no.1
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• pp.129-135
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• 2009

PPCP (pharmaceuticals and personal care products) is known as micropollutant that is released from wastewater treatment plant. Research represents that these contaminants have increased in the last 10 years. This study tries to make four different trickling filter systems using plastic fiber media to remove PPCP such as acetaminophen, ibuprofen, caffeine. The results of the experiment that compares the process efficiencies of four different systems (A, B, C and D) using HBC media show that almost all the reactor has around 95% removal efficiency. Slope type HBC reactor has twice higher efficiency rather than submerged type reactor to remove PPCP in water system. In 8 hours, 89% of acetaminophen, ibuprofen, caffeine are removed in slope type reactor while 39% of them in submerged type.

• Proceedings of the KIEE Conference
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• 1997.07a
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• pp.177-180
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• 1997

A new excitation method of switched reluctance moor drive is described in this paper. This motor produces reluctance torque by mutual action between tyro phases as well as conventional self reluctance torque. The change of self inductance and mutual inductance are used to produce torque. This paper suggests the operational principle, the mechanism of torque product and the driving characteristics of Switched Reluctance Motor with 2 phase excitation against conventional SRM experimentally. The energy conversion ratio is increased because the next phase is excited after one phase is already excited. Acoustic noise of SRM with 2 phase excitation is decreased than that of conventional SRM due to the mechanism of torque production.

• Journal of IKEEE
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• v.2 no.2 s.3
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• pp.166-172
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• 1998

Switched reluctance motor(SRM) has the advantages of simple structure, low rotor inertia and high efficiency. However, position sensor is essential in SRM in order to synchronize the phase excitation to the rotor Position. The Position sensors increase the cost of drive system and tend to reduce system reliability. This paper investigates the speed control of sensorless SRM in which the Phase current and change rate are utilized in position decision, and the period of dwell angle is variable for speed control. The proposed system consists of Position decision circuit, speed controller, digital logic commutator, switching angle controller and inverter The performances in the proposed system are verified through the experiment.

• Journal of Korean Medical classics
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• v.19 no.2 s.33
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• pp.179-195
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• 2006

의약학적존재화발전인소유내재인소(?約學的存在和發展因素有內在因素), 내재인소리유학문본신적특수이론계통(內在因素里有學問本身的特殊理論系統), 함유혼풍부적과학의의(涵有婚豊富的科學意義), 임상치료효과(臨床治療效果), 병인적신뢰등(病人的信賴等). 외재인소리유정치(外在因素里有政治), 정책(政策), 경제(經濟), 문화방면등등(文化方面等等). 저반인소중의학정책적영향시최직접화결정성적(著般因素中?學政策的影向是最直接和決定性的). 병차의학정책적직접인소리유의약방면유관적제도(幷且?學政策的直接因素里有?約方面有?的制度), 정책(政策), 법평등(法平等), 간접인소리유국가전장제도(間接因素里有國家典章制度), 국가방침화정책등(國歌方針和政策等). 재고대봉건사회상정책적개념시국가(在古代封建社會上政策的槪念是國家), 정당재특정역사시기상위료실현노선화임무(政?在特定歷史時期上爲了悉現路善和任務), 규정적행동준칙(規定的行動准則), 비여선황제적소(比如宣皇帝的沼), 령(領), 칙(勅), 유급정부적각중정령등(愉及政府的各?政領等). 본논문시대한한의학원전학회지상기고적(本論文是大韓韓?學原典學會指上寄稿的)[관우진한시기의정사연구(?于秦漢時基?政史硏究)]상여천명(上如闡明), 통과화중국량준교수공동연구적연속적연구결과(通過和中國梁畯敎授共同硏究的連續的硏究結果). 지우위진남북조시기적의정사(至于魏晉南北朝試期的?政史), 논자관우위진남북조정치개요(?者?于魏晉南北朝政治槪要), 의약정책(?約政策), 의정조직적초보구조(?政組織的初步柩?), 의약정책화의약발전관계(?約政策和?約發展關系), 관우의정평가와형성원인등분성오개방면후(?于?政?伽和形成原因等分成五介方面后), 진행연구병정리보고기결과(進行硏究幷整理報告基結果).

• Journal of Conservation Science
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• v.25 no.3
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• pp.317-322
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• 2009

Nicobium castaneum belonging to the family Anobiidae of Coleoptera was found in Jeju Folk Museum in 2006, Miribeol Folk Museum in 2007, and a bier preserved in the bier house of Jeju in 2008. We found that this species did considerable damage to the several wooden cultural properties. For Identification and pest management to conserve wooden cultural properties from this anobiid species, we report morphology of adult and damage pattern (shape of exit holes from the host, tunnels and their excrements etc).

• Journal of Korea Multimedia Society
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• v.24 no.7
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• pp.942-952
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• 2021

This study looked at the factors that shaped the identity of the Bupo-dong community through Dong-gye and Sangyeo-gye, mainly in the case of Bupori, Yeah, and Adong, and to identify that Dong-gye and Sangyeo-gye, played an important role in shaping and strengthening the community culture of its members. As a result of his inspection, Bupo-dong formed and maintained his belonging and identity as a member of Bupo-dong through the Dong-gye, the town's autonomy code. We were able to confirm that bupo-dong, unlike other villages where community culture is largely destroyed, has been able to continue its own community culture as a bupo people to this day, with a sense of belonging, solidarity and intimacy through the Sangyeo-gye of cooperation and relief. And it can be seen that the fact that the Burawon space, which has symbolic meaning to the people of Bupo-dong, exists without being watered down. It is important to discuss the community culture of Bupo-dong, which is sustainable, mainly in Bura-dong, which continues to be an important cultural space for bupo-dong people to meet and town events.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.1
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• pp.48-54
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• 1987

To search for the optimal nitrogen application method for the machine transplanting to Dongjinbyeo, compared to conventional method, in the various methods of nitrogen split application at different growth stages of rice plant. This experiment was performed at Honam Crop Experiment Station, in 1985 year. The results were as followed; the nitrogen contents of leaf blade was the highest at maximum tillering stage under the conventional method and reduction division stage under the nitrogen top-dressing at panicle initiation and 5 times split application of nitrogen for the whole rice growth stages. CGR, RGR and NAR after heading was highest under 5 times split application of nitrogen for the whole rice growth stages. Relationships between CGR and NAR, NAR and RGR, CGR and RGR showed the positive correlation significantly at each rice growth stage, respectively, and showed more high correlation according to further rice growth stages. The degree of contribution of CGR to rice grain yield was the highest at 20 days after heading. Rice grail: yield was higher under top-dressing of nitrogen at panicle initiation and basal application (30%) + 4 times equal dispensing top-dressing after basal application of nitrogen than conventional method.