• Journal of Power Electronics
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• 제11권4호
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• pp.490-498
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• 2011

This paper presents a novel analysis, design, and implementation of a battery charging three-phase high frequency semi-controlled power converter feasible for plug-in hybrid electric vehicles. The main advantages of the proposed topology include high efficiency; due to lower power losses and reduced number of switching elements, high output power density realization, and reduced passive component ratings proportionally to the frequency. Additional advantages also include grid economic utilization by insuring unity power factor operation under different possible conditions and robustness since short-circuit through a leg is not possible. A high but acceptable total harmonic distortion of the generator currents is introduced in the proposed topology which can be viewed as a minor disadvantage when compared to traditional boost rectifiers. A hysteresis control algorithm is proposed to achieve lower current harmonic distortion for the rectifier operation. The rectifier topology concept, the principle of operation, and control scheme are presented. Additionally, a dc-dc converter is also employed in the rectifier-battery connection. Test results on 50-kHz power converter system are presented and discussed to confirm the effectiveness of the proposed topology for PHEV applications.

• 정보관리학회지
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• 제25권3호
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• pp.119-141
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• 2008

본 연구는 먼저 민간의 고객관계관리(CRM)시스템을 정부차원에서 적용한 정책고객관계관리(PCRM) 시스템의 개념과 현황, PCRM과 CRM의 비교, 그리고 통일부의 도입사례를 통해 PCRM의 핵심인 고객의 정의와 분류 과정에 대해 살펴본다. 다음, 통일부 소속 전문도서관인 북한자료센터의 사례를 통해 다른 정부기관 전문도서관에서의 활용 방향과 전자정부에서 시도된 다른 연계 시스템들과의 관계에 대해 논구한다. 마지막으로 이를 통해 PCRM이 전문도서관에서 발전적으로 정착하기 위해서 보안해야 할 문제에 대해서 고찰한다.

• 한국콘텐츠학회논문지
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• 제19권11호
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• pp.178-189
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• 2019

본 논문은 C. P. E. 바흐의 연구에서 심도 있게 다루어지지 않은 그의 푸가를 재평가하는 것에 목적이 있다. 푸가는 대위적인 음악 가운데 짜임새가 가장 정교한 음악으로 흔히 대조적 성격의 즉흥적 프렐류드나 판타지아와 한 쌍으로 이루어져 있기도 하다. C. P. E. 바흐는 여기서 한 걸음 더 나아가 두 악곡을 나란히 배치하는 것이 아니라 이 두 장르를 하나의 음악으로 융합시키고자 하였다. 푸가의 기본 개념과 전형적인 형식적 틀은 느슨하게 유지되고 있는 가운데 주제의 특징과 세부진행에서 그가 즉흥연주기법으로 피력한 바 있는 양식적 특징이 비중 있게 결합 되어있는 것이다. 본고는 C. P. E. 바흐 건반 푸가 전곡(7곡)의 분석을 통해 그가 추구한 즉흥연주기법과의 결합을 고찰한다.

• 대한한방내과학회지
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• 제20권1호
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• pp.48-56
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• 1999

This study has been carried out to investigate Brain in Nei-jing. The results of this study were as follows. 1. Kidney energy becomes the marrow by warm caring function of Meong-mun(命門) and the marrow becomes brain by ascending and gathering between a hole Back-hoi(百會) and a hole pung-ji(風池) 2. Brain is a sea of the marrow that five vital organs are eraporated togather. 3. In Nei-jing(內經), there is a explanation the connectin between brain and mind, thanking by drawing in a concept of head. 4. Brain regulrates physical excercise. 5. There is a direct connection between brain and biosis. 6. Brain achieves function of sense, relating with the five sensory organs. 7. Brain controls a change of emotion. 8. Brain has immunological function.

• 한국수학교육학회지시리즈A:수학교육
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• 제41권1호
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• pp.19-34
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• 2002

The 7th national mathematics curriculum lays emphasis on an interrelation of several subjects and a connection between mathematics and real life. In this reason, this study focuses on the enhancement of sound understanding nuclear energy which is one of important factor(concepts or contents) dealt with in the other subjects such as science, environment, social studies, etc.. Recently, even though it is insistent that nuclear energy be so important and request in the future society, there are still strong pro and cons regarding the use of it. In this study, teaching-and-learning materials were developed dealing with using nuclear energy, and consequently they might be used in math class for the purpose of enhancement of mathematical learning ability and of recognition on nuclear energy. In this study, Material 1 included a matter of the necessity for nuclear power plants using the ratio concept, and Material 2 did on a matter of the efficiency of nuclear energy and the unclear of nuclear power plants using ratio-graph, in the elementary and upper school mathematics. Material 3 focused on a matter of the principles of nuclear power plants using the properties of exponential law in high school mathematics. Ultimately, it is hoped in the study that more diverse instructional materials dealing with diverse situations inside and outside mathematics would be developed.

• 한국의류학회지
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• 제33권1호
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• pp.127-138
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• 2009

This study is about the analysis on symbolic meaning and kunstwollen of Issey Miyake's art works which is influenced by various external factors such as social and cultural background, nationality and philosophy. Especially, this research focused on 'Pleats Please Issey Miyake' and 'A Piece of Cloth' which are the core of his works. The most important concept of Issey Miyake's works is the relationship of human body and a piece of cloth. Miyake's clothes has provided the time and the space where inspires the vitality into wearer. He accomplishes the most perfect beauty through incomplete beauty of cloth. Miyake wants to express the emotion of the human being through his clothes and tries to make special code between creator, wearer and viewer. Fashion is accomplished in connection with human body, not exists just as 'clothes'. Fashion has valued as an art which expresses the ideology and the sentiment of human being most directly. Issey Miyake who has tried to express human life and emotion has promoted fashion as an important part of art. Miyake is accepting and delivering the history and culture, expressing and communicating empathy, and combining the different fields harmoniously.

• 한국주거학회논문집
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• 제14권6호
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• pp.193-204
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• 2003

In connection with the plan for improving the residential environment gradually by analyzing the present condition of the reconstruction and parcel form of the housing area in a inner area, the main objective of this research is to develop a cooperative urban housing model based on the neighborhood agreement. The parcel form has a structure that is inappropriate for individual reconstruction； thus, the substantial improvement only through the residential environment improvement project has its limitations. As an alternative plan to resolve such limitations, I proposed a system that enables step-by-step reconstruction within the small-scaled blocks through the annexation of the land based on the neighborhood agreement. Nonetheless, I realized that it is difficult to apply such reconstruction system to individual housing. Therefore, I presented a design concept on the cooperative urban housing project as a residential form for the reconstruction inside blocks. A model plan vouches for its effectiveness. To apply substantially the cooperative urban housing plan based on the neighborhood agreement, we need to supplement the sectional plan system.

• Journal of Communications and Networks
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• 제17권3호
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• pp.286-295
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• 2015

Avionic databuses fulfill a critical function in the connection and communication of aircraft components and functions such as flight-control, navigation, and monitoring. Ethernet-based avionic databuses have become the mainstream for large aircraft owning to their advantages of full-duplex communication with high bandwidth, low latency, low packet-loss, and low cost. As a new generation aviation network communication standard, avionics full-duplex switched ethernet (AFDX) adopted concepts from the telecom standard, asynchronous transfer mode (ATM). In this technology, the switches are the key devices influencing the overall performance. This paper reviews the avionic databus with emphasis on the switch architecture classifications. Based on a comparison, analysis, and discussion of the different switch architectures, we propose a new avionic switch design based on a time-division switch fabric for high flexibility and scalability. This also merges the design concept of space-partition switch fabric to achieve reliability and predictability. The new switch architecture, called space partitioned shared memory switch (SPSMS), isolates the memory space for each output port. This can reduce the competition for resources and avoid conflicts, decrease the packet forwarding latency through the switch, and reduce the packet loss rate. A simulation of the architecture with optimized network engineering tools (OPNET) confirms the efficiency and significant performance improvement over a classic shared memory switch, in terms of overall packet latency, queuing delay, and queue size.

• Steel and Composite Structures
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• 제5권6호
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• pp.443-458
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• 2005

Steel angles are widely used in roof trusses as web and chord members and in lattice towers. Very often angle members are connected eccentrically. As a result, not only an angle member is under an axial force, but it is also subject to a pair of end eccentric moments. Moreover, the connection at each end provides some fixity so neither pinned nor the fixed end represents the reality. Many national design codes allow for the effects due to eccentricities by modifying the slenderness ratio and reducing the compressive strength of the member. However, in practice, it is difficult to determine accurately the effective length. The concept behind this method is inconsistent with strength design of members of other cross-sectional types such as I or box sections of which the buckling strength is controlled by the Perry constant or the initial imperfection parameters. This paper proposes a method for design of angle frames and trusses by the second-order analysis. The equivalent initial imperfection-to-length ratios for equal and unequal angles to compensate the negligence of initial curvatures, load eccentricities and residual stresses are determined in this paper. From the obtained results, the values of imperfection-to-length ratios are suggested for design and analysis of angle steel trusses allowing for member buckling strength based on the Perry-Robertson formula.

• 해양환경안전학회지
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• 제19권1호
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• pp.37-44
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• 2013

본 연구는 다양한 기상변화에 따른 안전을 확보하기 위한 해상에서의 플로팅 플랫폼의 연결에 대하여 연구하였다. 본 연구의 목적은 다양한 해상변화가 일어나는 연안역에 설치되는 플로팅 구조물에 관한 문헌 조사를 실시한 후, 콘크리트 구조물 연결하는 모델을 제시하는 것이다. 본 연구에서는 플로팅 구조의 개념, 기존의 모델, 설계적 평가를 포함한 콘크리트 구조물 기반 플로팅 플랫폼을 기술하였고, Rigid Pontoon Connector를 국내 연안역에 적합한 모델로 제안하였다. 연구의 결과로서, 리기드 폰툰 커넥터 디자인은 (Rigid Pontoon Connector) 안정적으로 플로팅 플랫폼의 연결을 구축할 수 있는 매우 효율적이고 실용적인 솔루션으로 분석되었다.