• 한국의상디자인학회지
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• 제4권1호
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• pp.131-141
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• 2002

The present study, first, reviews theoretically previous studies about the concept and quality of services as well as tools to measure the quality. Second, it reviews theoretically previous studies about the concept and quality of special services as well as tools to measure the quality. According to the results of reviewing previous studies on service quality, it is considered that the variance among several researchers concerning the measurements of service quality is affected significantly by factors such as the procedures of data collection and analyses utilized in the studies. In addition, the fact that dimensions are different, or some dimensions are not independent, is highly likely to be based on the unique characteristics of business categories, in addition to research procedures. Accordingly, when measuring service quality in future studies, it may be desirable to adapt measuring tools partially for the characteristics of each service category, and to generalize the adjusted tools over the specific category. Especially studies on the quality of special service have been carried out in limited scope so far. Thus, it is required to develop and refine comprehensive and appropriate criteria and detailed questions to measure the quality of fashion education service. Furthermore, studies are necessary with regard to relations among relevant factors such as customers' satisfaction and perception on education service quality after they experience the services.

• Composites Research
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• 제24권2호
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• pp.9-13
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• 2011

본 논문에서는 zinc blende계열의 결정구조를 갖는 실리콘 내부의 결함을 분석할 수 있는 대칭축 파라메터 (Symmetric axis parameter)방법을 이용하여, 탄성 및 소성 변형을 구별하는 방법을 제시하였다. 분자 동력학 해석프로그램인 LAMMPS를 사용하여, 실리콘에 대한 나노인덴테이션 해석을 수행하였다. 구형 인덴터 아래에 발생한 실리콘내부의 결함은 ring crack에서의 threefold 무늬와 전위발생경로를 보여주였다. 또한, 해석결과는 기존의 이론이나, 실험결과와도 일치하는 것을 확인하였다.

• 대한기계학회논문집
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• 제16권10호
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• pp.1841-1852
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• 1992

본 연구에서는 Fig.1과 같이 원형튜브 형태로된 시편과 실린더 형태의 시편을 Single Lap Joint의 형태로 접착하여 접착제의 두께에 대한 정적 비틀림 강도특성을 실험하였으며, 접착제의 경화시 외부에서 가해주는 열로 인한 열 잔류응력의 영향에 대한 연구를 수행하였다. 또한 이론적인 해석과 상용 프로그램인 ANSYS를 이용하여 유한요소해석을 병형하여 실험결과와 비교 검토하였다.

• Journal of Mechanical Science and Technology
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• 제14권9호
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• pp.935-946
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• 2000

Elastic-plastic stress analysis has been performed to evaluate the fatigue life of an autofrettaged pressure vessel containing cross-bores subjected to pulsating internal pressure of 200 MPa. Finite element analyses were used to calculate the residual and operating stress distributions of the pressure vessel due to the autofrettage process and pulsating internal pressure, respectively. Theoretical stress concentration factors of 3.06, 2.58, and 2.64 were obtained at the cross-bore of the pressure vessel due to internal pressure, 50%, and 100% autofrettage loadings, respectively. Local stresses and local strains determined from the elastic-plastic finite element analysis were employed to calculate the failure location and fatigue life of the pressure vessel with radial cross-bores, incorporating the low-cycle fatigue properties of the pressure vessel steel and fatigue damage parameters. Increase in the amount of overstrain by autofrettage process moved the crack initiation location from the inner radius toward a mid-wall, and extended the crack initiation life. Predicted fatigue life of the fully autofrettaged pressure vessel with cross-bores increased about 50%, compared to the unautofrettaged pressure vessel. At the autofrettage level higher than 50%, the failure location and fatigue life of the pressure vessel were not significantly influenced by the autofrettage level.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제4권3호
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• pp.273-288
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• 2010

In this paper, we propose a cooperative multi-relay scheme for a secondary system to achieve spectrum access along with a primary system. In the primary network, a primary transmitter (PT) transmits the primary signal to a primary receiver (PR). In the secondary network, N secondary transmitter-receiver pairs (ST-SR) selected by a centralized control unit (CCU) are ready to assist the primary network. In particular, in the first time slot, PT broadcasts the primary signal to PR, which is also received by STs and SRs. At STs, the primary signal is regenerated and linearly combined with the secondary signal by assigning fractions of the available power to the primary and secondary signals respectively. The combined signal is then broadcasted by STs in a predetermined order. In order to achieve diversity gain, STs, SRs and PT will combine received replicas of the primary signal, using selection combining technique (SC). We derive the exact outage probability for the primary network as well as the secondary network. The simulation results are presented to verify the theoretical analyses.

• 대한수학교육학회지:수학교육학연구
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• 제13권2호
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• pp.143-157
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• 2003

본 논문은 수학 교사 학습과 전문성 신장에 관한 보다 종합적이고 체계적인 이해를 증진하기 위한 노력의 일환으로, 우선 교사 학습을 이해하기 위한 다양한 이론적 틀을 검토하고 교사 학습과 관련하여 지식과 교수 관행간의 관계를 조사하며 탐구 공동체를 중심으로 한 효율적인 전문성 신장에 관한 아이디어를 분석한다 이와 같은 이론적 분석에 터해 교사 학습과 이에 관련한 수학교실문화의 변화 과정을 연구하는 프로젝트를 간단히 소개하고 탐구 공동체의 운영, 교사의 관점에서 교수 관행을 기술하는 것, 공동체에서의 교사 학습을 분석하는 것 등 프로젝트를 수행하면서 부각되는 문제점에 대해 논의한다.

• 비파괴검사학회지
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• 제20권3호
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• pp.221-230
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• 2000

콘크리트 비파괴검사법인 충격공진법의 유용성과 적용 한계를 살펴보기 위하여 실험 및 이론적 연구를 수행하였다. 실험적 연구를 위하여, 다양한 개재물이 포함된 콘크리트 슬래브 공시체를 제작한 후 충격공진법을 적용하여 개재물의 존재 및 매실 위치를 찾아보았다. 공시체들 중 몇 경우에는 개재물의 위치를 정확하게 검출할 수 있었으나, 나머지의 경우에는 검출하지 못하였다. 후자의 경우에 있어서 그 실패 원인을 규명하고, 나아가 본 기법의 유용성을 결정하는 주요 인자들을 알아보기 위하여 유한요소 해석을 수행하였다. 본 연구는 충격공진법의 물리적 이해 증진과 향후 발전에 기여할 것이다.

• 한국정밀공학회지
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• 제21권1호
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• pp.109-115
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• 2004

Polishing process has been applied to get extremely fine surfaces, e.g., mirror surfaces such as optical mirrors, lens, molds and etc. Nowadays not only fine surface quality but also submicron order of dimensional accuracy is required for many applications. To meet the requirements polishing process should be provided with an active control of polishing pressure especially for automation of polishing process. In this paper a study on development of an active polishing pressure control system has been presented. A new type of tool assembly has been developed to facilitate the control. The tool is attached to an axis of a polishing machine with a coil spring and control of the polishing pressure is done by the position control of the axis, which needs no additional actuator. The polishing pressure is successfully measured by the measurement of the spring deformation. Control specifications were quantitatively considered by weighting functions and a controller was designed by using loop-shaping technique based on the no synthesis. Some experiments have been executed on a polishing machine with a PC-NC controller. It is shown that the results were coincident well with the theoretical analyses and satisfied the design specifications.

• 신재생에너지
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• 제2권2호
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• pp.102-107
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• 2006

In Japan, research and development were undertaken on gas hydrate-side industrial processes associated with power generation system connections that may particularly be necessary to develop gas hydrated technology-based industrial systems. In so doing, data and engineering technologies useful n formulating guidelines on design of practical process were accumulated. In addition, basic research into theoretical evidence were carried out to promote and support the development of technological elements for those processes. In basic research designed to promote and support the research and development of elemental technologies, microanalyses were conducted to understand the decomposition mechanism of mixed gas hydrate. Moreover, measurement technologies that can be applied in industrial processes, such as numerical analyses and concentration measurement, were examined. Japan has developed a highly efficient gas hydrate formation process using micro-bubbles with a tubular reactor. Higher formation rate over conventional systems has been obtained by the process. As mentioned above, the technical problems were clarified and the economics were studied from a view point of the NGH technology in this study. The results can be applied for utilization and must contribute to popularization of gas hydrate production.

• 한국콘텐츠학회논문지
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• 제11권7호
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• pp.80-88
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• 2011

눈에 보이지 않는 소프트웨어의 품질을 측정하고 관리한다는 것은 쉬운 일이 아니다. 하지만 소프트웨어개발 프로젝트가 대형화, 복잡화됨에 따라 그 중요성을 간과할 수 없다. 본 연구에서는 소프트웨어 품질 개선을 위한 방법들의 특징을 비교 분석하였다. 그리고 코드 인스펙션(Code Inspection)을 위한 규칙들을 수립하고 실제 프로젝트에 적용함으로써 그 효율성과 효과성을 검증하였다. 본 연구를 통해 다음과 같은 결과를 얻었다. 첫째, 소프트웨어 검토 방법들에 대한 이론적 내용을 정리한 점이다. 둘째, 코드 인스펙션을 위한 규칙을 수립하고 사례를 통해 성과를 증명하였다. 셋째, 코드 인스펙션을 통해 정량적 데이터 관리를 수행하였다.