• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제10권2호
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• pp.81-88
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• 2006

슈퍼 컴퓨터의 등장으로 기존에는 풀지 못했던 과학적, 학술적인 문제들이 대부분 해결되었지만 슈퍼 컴퓨터 자체의 막대한 비용 문제는 여전히 풀지 못한 숙제로 남아 있다. 이에 일반 사용자의 컴퓨터의 유휴 자원을 통합하여 협업하는 그리드 컴퓨팅이라는 개념이 등장하였다. 한편 분산되어 있는 이기종의 시스템의 자원을 통합하여 관리하기 위해서 연결 지향적인 프로토콜들이 사용되었지만, 다른 프로토콜끼리는 호환성이 없는 등의 문제가 존재한다. 본 논문에서는 플랫폼 독립적인 XML 기반의 SOAP을 사용하는 웹 서비스를 이용하여 그리드 네트워크의 성능 정보를 관리해주는 시스템을 제안한다.

• 정보처리학회논문지D
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• 제8D권4호
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• pp.439-450
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• 2001

Mobile agent is one of the promising ways of overcoming network load and latency. It is also a new software paradigm including those concepts of client/server, applet/servelet, and code-on-demand. In this paper, a new mobile agent concept with flexible replay scheme is proposed, which can deal with embarrassing situation when replying results should be accomplished in various distributed applications. For example, they are 1) a burden of bulky result, 2) a need of different replay scheme dependent on work type, 3) connection failure to the target node, and 4) a need of fast migration to next node to keep the itinerary. Regarding the source node, there may be another situation that it wants to be aware of whether its wi가 is completed or not. Three kinds of reply schemes are proposed for dealing flexibly with such situations. They are based on priority reply list where nodes to be replied are stored according to their priorities. An experimental supply chain management model using the proposed reply schemes is designed and implemented. It is one of good distributed applications appropriate for our reply schemes, because it requires different reply schemes according to work types and it is important to gather required information in time.

• 한국실내디자인학회논문집
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• 제13권4호
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• pp.138-146
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• 2004

The museum has been developed and changed variety by a social change and extention of its concept and social role. At modem times, context is a important fact in museum architecture in the city. These mean that museum architecture is combined with rather the relationship its surroundings than completion its constructing. Recently, Many studies were continued on the assumption that the function and role of museum has been changed variety by a social change. But most of them were centered on changing choronogical typology of museum layouts and classifing morphology of museum. This study is to analyze harmony and connection about pinakothek der moderne with surounding conditions and to know how to design its spacial configuration. As a result of this study, firstly, it was confirmed that pinakothek der moderne came up with an idea which was design method about planning of modern museum in classic museums district. Seondly, it come under the modern museum but has classical spacial form and faculty. These mean that it is not only a solution about required functions but also a trial that is a significance for solving historical context and esteeming the classic space.

• 건축역사연구
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• 제5권2호
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• pp.53-68
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• 1996

This study is on the early historical background and the process of development of modern architecture in Thai, during the period from 1782(King Rama 1) to 1934(King Rama 7). Thai started tn form a connection with western nations from the late 18C, founded the Bangkok Dynasty. Since then, Thai was increasingly influenced by western civilization and this trend included an increasing influence of western architecture. In this paper, the centeral objective is to observe the architectural change during the period from King Rama 1(1782-1809) to King Rama 7(1925-1934). This can be divided into three period. During the first period, from King Rama 1 to King Rama 3(1824-1851), Thai architecture showed a tendency to follow the preceding traditional example and to imitate Chinese architecture. The second period is from King Rama 4(1851-1868) to King Rama 5(1868-1910). During this period, Thai architectural design was increasingly influenced by western concepts, specially European Neo-classicism Style. During the third period, from King Rama 6(1910-1925) to King Rama 7(1925-1934), Thu had been enjoying extensive commerce with western nations. The great developments in the field of architecture during this reign were apparent in the construction of public utilities and facilities. These buildings were designed by western architects. At this time, modern architectural concept of western was introduced.

• 디지털콘텐츠학회 논문지
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• 제7권2호
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• pp.89-94
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• 2006

전 세계적으로 큰 파장을 일으키고 있는 P2P 비즈니스는 인터넷의 급속한 보급과 더불어 고속 인터넷 접속 서비스가 확산되고, 고성능 PC 보급을 통한 사용자 환경이 강화되면서 가능하게 되었다. P2P란 서버와 클라이언트 개념에서 벗어나 개인 컴퓨터끼리 직접 연결하고 검색함으로써 모든 접속자가 공급자인 동시에 수요자가 되는 형태를 말한다. 최근 P2P는 개인간의 단순한 파일공유 서비스가 아닌 기업 간 전자거래에 응용하는 등 다양한 시스템이 개발되고 있다. 본 연구에서는 기존의 P2P의 기능을 보완한 보다 효율적인 시스템을 제안한다.

• 대한수학교육학회지:학교수학
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• 제13권4호
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• pp.563-580
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• 2011

본 연구에서는 은유에 대한 인지언어학적 견해를 바탕으로 은유 이론을 수학교육에 적용함으로써 교사들에게 수학교육에 대한 새로운 시각을 제공하고 수학 학습 지도 방안으로서 은유를 활용하는데 그 목적이 있다. 먼저 은유에 대해 소개하고 은유를 수학교육의 관점에서 살펴보고 수학교육에서 은유가 갖는 의의를 알아보았다. 또한 은유가 가진 기능들을 중심으로 은유와 수학교육과의 관련성을 논의하고 은유를 활용한 수학 학습 지도 방안에 대한 아이디어를 제공하고자 하였다. 그 결과 은유가 설명적, 정교화, 표상적 기능을 가지고 있음을 밝혔고, 이를 수학적 개념 설명, 수학적 연결성 강화, 수학적 표상 학습에 적용하는 것이 은유를 활용한 수학 지도 방안이 될 수 있음을 예시하였다.

• 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.

• 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.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집B
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• pp.618-623
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• 2001

In a practical vibration isolation system, vibration is transmitted from the source to the receiver through several paths such as more than one inter-connected point and multi-degree of freedom at each connection point. Therefore, the major path investigation for vibration transmission among them is often required in a point of view of isolation. For the path analysis of multi-dimensional vibration isolation system, it is useful to employ the concept of vibration power in high frequency range where radiation of noise from the receiver structure is concerned. The idea is simple to understand and formulate but rather complicated to apply in practice. For an accurate estimation of power flow especially over a high frequency range, it is well known in theory that rotational motions should be taken into consideration together with translational motions at inter-connected points. In reality, however, power transmissions related to rotational terms are often neglected mainly due to difficulties in the instrumentation. In this paper, necessary formula and measurable mechanical quantities for vibration power analysis will be reviewed and experimental results with rotational terms included for compressor system in a commercial air conditioner will be shown.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 추계학술대회 논문집
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• pp.356-361
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• 2005

Earth brush for electrical multiple units(EMUs) is a device through which the current of the EMU load's consumed power fed from the DC 1,500V overhead line (or from the AC 25.000V catenary) flows via axle to the rail(ground) and which prevents the electric corrosion of the axle bearings by preventing the current flow to the axle bearings caused by electric potential from the magnetic field when the bearings rotate together with the earthing function when a thunderbolt falls or a surge comes. The earth brush wear rates among cars, however, shows quite differences when the earth brushes after being separated from the holders are measured with vernier callipers every 6 months of maintenance period. Main causes of the earth brush wear are divided as mechanical, electric arc and electrical one, and the factors can be running speed, current, harmonics, connection state. spring tension, earth brush material, lubricant and so on. but only the earth brushes of the motor(M1) car show the highest wear rate and moreover maintenance difficulty occurs because of the wear rate differences among e earth brushes in one holder. The reason for these preponderant wear comes from the design concept of making preponderant current flow to some particular earth brushes and moreover the heat generated by the harmonics when the inverter starts to operate accelerate the wear. By defining these causes through experiments. I hope that the found results would be helpful for the future EMU design, safety, economy and maintenance.