• Structural Engineering and Mechanics
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• 제12권2호
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• pp.201-214
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• 2001

Four finite element (FE) models are examined to find the one that best estimates moment-rotation characteristics of top- and seat-angle with double web-angle connections. To efficiently simulate the real behavior of connections, finite element analyses are performed with following considerations: 1) all components of connection (beam, column, angles and bolts) are discretized by eight-node solid elements; 2) shapes of bolt shank, head, and nut are precisely taken into account in modeling; and 3) contact surface algorithm is applied as boundary condition. To improve accuracy in predicting moment-rotation behavior of a connection, bolt pretension is introduced before the corresponding connection moment being surcharged. The experimental results are used to investigate the applicability of FE method and to check the performance of three-parameter power model by making comparison among their moment-rotation behaviors and by assessment of deformation and stress distribution patterns at the final stage of loading. This research exposes two important features: (1) the FE method has tremendous potential for connection modeling for both monotonic and cyclic loading; and (2) the power model is able to predict moment-rotation characteristics of semi-rigid connections with acceptable accuracy.

• Steel and Composite Structures
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• 제15권3호
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• pp.299-322
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• 2013

In the case of seismic-resistant composite dual moment resisting and eccentrically braced frames, the current design practice is to avoid the disposition of shear connectors in the expected plastic zones, and consequently to consider a symmetric moment or shear plastic hinges, which occur only in the steel beam or link. Even without connectors, the real behaviour of the hinge may be different from the symmetric assumption, since the reinforced concrete slab is connected to the steel element close to the hinge locations, and also due to contact friction between the concrete slab and the steel element. The paper presents the results and conclusions of experimental tests on composite portal eccentrically braced frames and beam-to-column moment-resisting joints, carried out within the CEMSIG Research Centre of the Politehnica University of Timisoara, in order to check the validity of the assumption stated above. Reference steel and composite specimens with and without connectors in the plastic zones have been tested under monotonic and cyclic seismic type loading.

• 융복합기술연구소 논문집
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• 제10권1호
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• pp.25-29
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• 2020

Magnetic gears of non-contact power type have great advantages in terms of maintenance and repair than mechanical gears, and are used in various ways. Harmonic gears can derive a higher gear ratio than conventional gears through power transmission through a unique rotation mechanism. Magnetic harmonic gears, in which the gear teeth of the harmonic gears are replaced with magnets, have the advantages of both gears, but are difficult to implement and practical, so many studies are being conducted. In this study, we check whether the results of various types of magnetic gears can be applied to harmonic gears. By applying the axial type magnetic gear to the harmonic gear, the characteristic analysis is conducted to see if the result comparable to the existing radial type magnetic harmonic gear is obtained.

• 한국지능시스템학회논문지
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• 제23권3호
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• pp.238-243
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• 2013

본 논문에서는 이족 보행 로봇을 위한 무릎 및 힙 관절의 일 특성을 분석하고자 한다. 이를 위하여 컴플라이언스 특성의 발을 갖는 이족 로봇 다리 메커니즘을 대상으로 전형적인 보행 패턴을 고려한다. 또한 딱딱한 지면과 접촉하는 로봇 발 공간으로부터 다리 관절 공간으로 전파되는 토오크 특성을 확인하고, 보행에 따라 관절 공간에 누적되는 일 특성을 제시한다. 결과적으로, 이러한 분석이이족 로봇의 보행에서 발과 지면의 물리적인 접촉에 의한 다리 메커니즘의 피로 정도를 파악하는데 있어서 유용하고, 적절한 신발 착용 등에 의한 로봇 발 공간에서의 컴플라이언스특성 개선에 활용될 수 있음을 보인다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 춘계학술대회 논문집 센서 박막재료연구회 및 광주 전남지부
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• pp.10-14
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• 2008

In this paper, abnormal heating of circuit breaker in panel board by poor connection was studied. Firstly, calculation method of contact resistance shown in IEC 60943 was examined. Secondly, concerning abnormal heating of circuit breaker in panel board, field measurements were performed. Field measurements showed that locally abnormal heating by poor connection could be detected, therefore, in that case, immediate action was needed. Finally, experiments regarding abnormal heating between terminal of circuit breaker and electric wire were conducted. The results showed that abnormal heating above $180^{\circ}C$ was measured. Also, in the results of analysis of electrical waveforms according to load current, voltage drop occurred around poor connection, and the oxide was generated according to mechanical vibration. In order to prevent electrical disaster caused by poor connection, adequate torque should be applied to electrical connection, and periodic check-ups are needed.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제12권2호
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• pp.17-30
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• 2006

The wealth of Korean disability people's paradigm has developed by the meaning of whole rehabilitation of the small society for acception and protection. Today, that meaning has been changed to make and choose disability people's future plans by themselves. The CENTER FOR INDEPENDENT LIVING in Korea has been accepted through the American and Japanese's activity systems with no objection. Following result of the real reserching, because the CENTER FOR INDEPENDENT LIVING in Korea have no legal basement, so there are little support for these centers and no proper rules and check systems. Therefore, we have to make the legal basement of CENTER FOR INDEPENDENT LIVING and separate by each parts of system and to specialize about them. That means, each parts of system have to mark role mode for doing well, and each systems have to develop new programs and services, and to specialize for in Korea. To add, we should have more small CENTER FOR INDEPENDENT LIVING in each area, and the CENTER FOR INDEPENDENT LIVING which are already started should make network system to contact with other centers in society for giving support of proper information.

• 한국콘텐츠학회논문지
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• 제8권3호
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• pp.197-204
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• 2008

최근 경찰공권력 경시풍조가 사회적으로 큰 문제가 되고 있다. 음주측정 거부 및 도주, 주취자 행패, 경찰관의 공상, 경찰기물 파손 등 정당한 경찰공권력에 대항하는 현상이 점차 확산되어가고 있다. 경찰은 국민의 자유와 권리를 보호하고, 사회질서를 유지하고, 범죄를 예방 진압하기 위해 활동하는 국가기관이다. 이에 경찰공권력 실추는 국민들의 안전을 크게 저해하는 요인이 될 수 있다. 따라서 실추된 경찰공권력을 바로잡기 위한 노력이 필요할 것으로 보인다. 이에 이번 연구에서는 최근 급격히 증가한 경찰공권력실추의 추세를 살펴 본 후 경찰공권력 실추에 영향을 미치는 사회 문화적 특성에 대해 살펴보도록 한다. 이와 더불어 경찰공권력의 회복을 위한 방안을 모색해 보고자 한다.

• 유공압시스템학회논문집
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• 제7권1호
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• pp.1-5
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• 2010

This paper presents the experimental results of the radial piston type oil pump with new mechanism for a metal diaphragm hydrogen compressor. Generally, metal diaphragm type hydrogen compressor systems are operated by oil hydraulic power. In this system an oil compensating pump has been demanded to compensate for a leakage oil head chamber. The metal diaphragm type hydrogen compressor consists of an oil compensating pump, commonly used hydraulic piston pump and driven by main crank shaft. The radial piston type oil compensating pump with new rolling contacted piston mechanism is developed and experimented. The developed piston element of the radial piston pump consists of piston, steel ball, return spring, two check valves, eccentric cam and ball racer. In this study, designed 4 type pistons as and orifice hole. Operating characteristics and pressure ripple characteristics are tested under no load to 60bar loaded with every 20bar increasing step and pressure ripple and flow rate are experimentally investigated.

• International Journal of Costume and Fashion
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• 제16권2호
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• pp.67-79
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• 2016

The Oroqen (鄂伦春) traditional costume refers to what the nomadic Oroqen people used to wear before they settled into fixed communities. With very limited contact with the outside world and with limited resources, the clothing material was virtually entirely animal hide. With settlement, especially after 1996, animal hide clothing has declined among the Oroqen. As an important part of Oroqen tradition and culture, the Oroqen people keep endevoring to promote costume design through competition and exhibitions. Therefore, this paper seeks to present an insightful understanding of Oroqen culture and the formative features of their general clothing. We explored the formative features of Oroqen animal hide clothing based on an analysis of actual artifacts and literature. As a result, the characteristics of Oroqen hide clothing were found in five types - coats, trousers, hats, shoes, gloves. For the decoration, embroidery and applique were their way of decoration, and Mother Nature was their source of pattern design.

• International Journal of Advanced Culture Technology
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• 제8권2호
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• pp.246-251
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• 2020

Dimethyl Ether(DME) engine use a highly efficient alternative fuel having a great quantity of oxygen and has a advantage no polluting PM gas. The existing DME fuel cam material is a highly expensive carbide alloy, and it is difficult to take a price advantage. Therefore the study of replacing body area with inexpensive steel material excluding piston shoe and contact area which demands high characteristics is needed. The development of WC-Ni base carbide alloy optimal bonding composition technique was accomplished in this study. To check out the influence of bonding temperature and time, bonding characteristics of sintering temperature was experimented. The hardness of specimen and bonding rate were measured using ultrasound equipment. The bonding state of each condition was excellent, and the thickness of mid-layer, temperature and maintaining time were measured. The mid-layer thickness according to bonding temperature and maintaining time were observed with optical microscope. We analyzed the micro-structural analysis, formation of bonding specimen, wafer fabrication and fuel cam abrasion test. Throughout this study, we confirmed that the fuel cam for DME engine which demands high durability against velocity and pressure is excellent.