• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.300-305
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• 2009

High-rise buildings have some problems by stack effect. And, the solutions on the problems should be determined by considering an overall building. But, ordinarily, the countermeasures on the problems are applied to local part of the building. Local countermeasures often can be possible to arouse the secondary problems accompanied by the stack-effect. In this study, the usefulness of local countermeasures are evaluated in terms of both the reduction effect on problems and the possible secondary problems with simulations. The simulation results show that the application of countermeasures on an overall building is very important and that local countermeasures can be used optionally according to building's conditions.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 추계학술대회 논문집
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• pp.301-306
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• 2011

In this paper, active noise barriers for attenuation of road noise are proposed. multi-channel audio systems, DAQ part and high performance DSP H/W were designed. Active noise control firmware programs were implemented for multi-channel off-line/on-line estimation methods for secondary path transfer functions and FIR/IIR filter structure are used main noise control algorithms. To evaluate performance of proposed systems, the experiments were performed in an active noise barrier test bed for various noise cases.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.220-223
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• 2007

The key role of MgO is well recognized in PDP's technology. During manufacturing, significant contamination of the oxide occurs. Getters can compete against the impurities sorption speed of the oxide layer. The analysis of the impact of a suitable getter configuration on the operational parameters of PDP's is the final goal of this study.

• 전기의세계
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• 제13권2호
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• pp.1-4
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• 1964

Phase transformation is used to change some phase from phase in A.C. system. We have been used Scott or Fork connection in phase transformation the otherwise phase transformation was constructed from M-G set. From this M-G set, we could make phase shift facilities by mannual. Now, I can derive more easy phase transformation from taking another method. I believe this new phase transformation method in the first thing in the world. And so, I am going to explain about phase transformer construction process. The first, we could devide into equal part of core around the iron core as to be same size. The second, you will make primary and secondary winding on the core. The third, when you will supplied three phase A.C. at the terminal of primary winding you can get e.m.f. inducing of some phase at secondary. And so, we could make phase change from some phase A.C. We can apply this principle in many fields, i.e., freequency changer, phase leader of no use condenser, voltage regulator in keeping balance, and D.C. generator. And more, I will introduce in details concerning main pinciple and theory through following chapter.

• 한국초등과학교육학회지:초등과학교육
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• 제18권1호
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• pp.75-85
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• 1999

This paper describes some major trends in primary and secondary education now. It is a selective views of significant topics with important implication for the future. These trends are summarized as follows, after examining historical development of Teaching-learning Methodology in primary and secondary education. 1. Education is seen as part of interdisciplinary world; emphasis is on relating education to the students' world, which is not compartmentalized. 2. Emphasizing students' individual growth with their own goal of lives. 3. Open-education with variable contents and purposes of education. 4. Education for all from that for some. 5. Consructivist based from behavior based. 6. Cooperative learning, peer tutoring, group projects. 7. Authentic assessment; assessment integrated with instruction. 8. The teacher is a facilitator of learning and a learner as well; students are learners and teachers in some situations; networks emerge instead of one-way forms or communication. 9. Spiral curriculum from single exposure.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.482-485
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• 2004

On the basis of theoretical studies on the effect of the cylinders attached to semi-infinite screens, the tangential sound power-transport parallel to the surface of the attached cylinder is minimized by means of a secondary sound field, which is generated from a part of the attached cylinder. The numerical study shows the possibility of deflecting the incident sound by minimizing the acoustic surface impedance of the upper sections. The acoustical shadow region was more pronounced in both near- and far-field compared to the passive case with rigid surface, i.e. without active control. For a relatively wide frequency range it was possible to enhance shielding effects only with few secondary sources and error microphones. In this paper effects of some control parameters on the actively controlled sound field near the top edge of noise barriers are studied. Results of numerical study and model measurements are shown and discussed.

• 소성∙가공
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• 제18권2호
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• pp.160-165
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• 2009

A Study on Effects of the Runner and the Gate of double shot injection molded Parts using CAE Double shot injection molding can inject two different materials or two different colors in the same mold in a injection molding process. Double shot injection molded parts can be characterized that the base part maintains strength and specified part can inject soft-material. It can reduce the production cost by single automatic operations. In this paper, we designed double shot injection mold for automobile emote control To inject secondary part, this part is used as an insert after external appearance of product is injected. CAE analysis was progressed gate location and runner size as variables. The analysis result is reflected in mold design process. As a result, it could solve problems which are generated in the conventional mold. Additionally, cost can be downed by reducing runner weight. As well as it could omit painting process because the surface of finished product is improved through new mold.

• 한국주조공학회지
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• 제32권1호
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• pp.32-37
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• 2012

In this study, microstructural evaluation was carried out on secondary hardening type ultrahigh strength steel, Fe-Co-Ni composition. This paper as a first part of whole research presented the microstructural behavior by cyclic heat treatment. The cyclic heat treatment method includes normalizing, stress relieving, solution treatment and aging. Especially, solution treatments performed triple times to get maximized solution hardening. Phase transformation and microstructure were observed by using optical microscope (OM), Electron back-scattered diffraction (EBSD) and X-ray stress analyzer. During the triple solution treatment, size of grain boundary was dramatically decreased by generating a packet from the martensite transformation of residual austenite in the inner part of grain, whereas the hardness increase was not significant.

• 한국산학기술학회논문지
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• 제15권8호
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• pp.5355-5362
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• 2014

본 연구는 일제 강점기 중등학교 건축을 구성하는 필수시설이었지만 관련 연구가 부족했던 기숙사 건축의 계획 특성을 국가 기록원 소장 도면들을 대상으로 살펴보았다. 분석 항목은 배치 특성, 그리고 기숙사를 구성하는 주요 영역들인 개실동, 식당동, 사감실 영역 등의 계획 특성들이다. 연구 결과를 정리하면 다음과 같다. 1) 기숙사 영역은 교사동 영역 후면에 인접 배치되는 것이 일반적이었다. 2) 기숙사 영역은 남향을 원칙으로 하는 개실동들의 병렬배치가 배치의 기본형태가 되면서 식당동, 사감실 영역 등은 부지 상황에 맞추어 배치되었다. 3) 기숙사 개실동의 단위 평면은 대체로 한국인 학교의 경우 온돌형에 소형평면이 일본인 학교에는 다다미 마감에 자습실과 침실이 구분되어 있는 대형 평면이 적용되었다. 4) 식당동은 식당 영역, 취사장 욕실 영역 등으로 구성되며 일본인 학교의 경우 매점 영역이 함께 계획되었다. 식당의 평면 형상은 좁고 길며 복도가 연접해 있어 식당동 전체 평면은 편복도형 블록플랜과 같은 형상을 하는 것이 일반적이었다. 5) 사감실 영역은 차지하는 면적은 많지 않았지만 전체 기숙사를 대표하는 영역으로 상징적으로 보이도록 배치나 의장상의 고려가 있었다.

• 한국지반공학회논문집
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• 제15권6호
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• pp.87-98
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• 1999

연약지반에서의 압밀침하는 종종 구조물에 큰 피해를 미친다. 최근 국내에서는 대규모 프로젝트들이 계획 혹은 진행중인데, 이들 구조물들은 두꺼운 연약지반상에 건설되므로 설계나 시공에 있어서 각 단계별 정확한 압밀침하량 예측이 필요하다. 특히, 이러한 연약지반상의 이차압밀은 전체 압밀침하량에서 상당량을 차지하게 된다. 일반적으로 이차압밀은 실내 혹은 현장압밀시험을 통해 산정된다. 경험적인 $C_a/C_c$의 비는 이차압밀량을 예측하는데 있어서 경제적이고 효율적인 수단이 될 수 있을 것이나, 국내의 $C_a/C_c$는 그 데이터 베이스가 매우 부족한 실정이다. 본 연구에서는 간극수압을 측정하는 단계재하 압밀시험을 이용하여 남해안 해성점토에 대한 $C_a/C_c$의 비를 0.397로 제시하였다.