• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.12 s.148
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• pp.1619-1626
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• 2005

The durability of a stretch fabric is mainly related to the change in the dimension and mechanical properties of elastomeric fibers during wearing and washing. In this study, we examined the effects of washing temperature, presoaking time and the number of washing cycles on the change in length, tenacity, elongation at break, and permanent elongation after six repeated cycles of $100\%$ extension and relaxation of spandex yams with varying fineness and with a different rate of extension during heat-set. The spandex yarns continued to shrink as the wash temperature and the number of wash cycles increased. In addition, the finer spandex yams decreased in length more than the thicker yams. The increase in temperature and presoaking time tended to cause a slight decrease in the tenacity and elongation at break of the spandex yarns. Permanent elongation of the spandex yams also increased as the temperature, presoaking time and the number of washing cycles increased. Moreover, an extended presoaking time followed by washing at $40\%$ like repeated washing cycles showed the great increase in the permanent elongation of spandex yams. The thinner spandex yin had a better elasticity than the thicker one, since the former had a lower permanent elongation percentage than the latter. Based on the DSC thermograms, the melting points of the spandex yarns after washing were almost the same as those of the spandex yarns before washing.

• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.4
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• pp.146-154
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• 2011

Recently, the paradigm of social infrastructure investment has been changed from new construction to maintenance and management. As a consequence, the management and maintenance system of existing highway facilities needed an innovation involving the concept of asset management. This paper discusses the new facility management system suitable to local highway agencies. The new system incorporates asset management concept so that it can analyze the network level facility management solution and it can also improve the budget efficiency for local government. This paper also presents systematic method to integrate various facilities for management system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.2
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• pp.638-645
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• 2014

This paper presents results of a study for development and application of container massive transportation system. The system is aimed to improve competing power of Korean container ports. This paper selects Double stack Multi-Trailer System (DMTS) under consideration of pros-con analysis between three systems alternatives as well as operation process of existing Korean container terminal companies. An analysis of turning radius is undertaken for applying the system. Key elementary technologies was derived by patent analysis. DMTS has no problems in utilization to existing Korean container ports. Further, the system is expected to highly potential to improve operational efficiency in the container ports thanks to its high unit transportation capacity.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11b
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• pp.505-510
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• 2002

The attenuation of waves transmitted through non-conservative joints that are shown in many paractical structures, is affected by the impedance and the orientation of the joint. In this paper, the joints between plate structures are assumed to be modeled as linear spring-dashpot systems and the transmission and reflection of vibration energy in the medium to high frequency ranges are investigated. The calculated power transmission and reflection coefficients are applied to the PFA method for the prediction of energy density and intensity in structures.

• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.6
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• pp.238-246
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• 2000

In this paper, an optimization method of thin walled beam structures is proposed, Stiffnesses of a thin walled beam are characterized by the thickness of thin plates and the shape of the typical section of the beam. Explicit formula for section properties such as area, area moment of inertia, and torsional constants are derived using the response surface method. The explicit formula can be used for the optimal design of a structural system which consists of complicated thin walled beams. A vehicle structural system is optimized to demonstrate the proposed method.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2013.06a
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• pp.134-137
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• 2013

방송통신위원회 "장애인방송 편성 및 제공 등 장애인 방송접근권 보장에 관한 고시"[1] 8조3항에서는 장애인방송물을 제작 송신 재송신할 경우에 대하여, 한국정보통신기술협회(이하 "TTA")에서 제정한 시청각장애보조방송서비스 기술표준의 준수를 의무화 하고 있다. 이에 TTA에서는 시청각 장애 보조 방송 서비스 관련 모든 방송매체 공통의 시청각 장애 보조 방송 서비스 표준의 기술을 검증하고 장애인방송 의무 적용에 대한 정부 정책 및 방송사업자 업체 대상 상용화 적용 시험을 지원하고자 장애인방송 수신기 시험환경과 장애인방송을 송신 및 재송신하는 방송매체의 송출스트림의 표준적합성을 검증할 수 있는 시험환경을 개발하였다. 본 논문에서는 "시청각 장애 보조 방송 서비스"[2]표준의 자막방송 및 화면해설방송을 시험하기 위한 시험환경 및 시험도구 개발 내용을 소개한다.

• Journal of the Korean Society of Costume
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• v.11
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• pp.51-60
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• 1987

The penetration force of needle and penetration energy kave been investigated, in order to research into the sewing factors that influence the weft knitted fabric with high elastic property. The results of the studies are a follows: (1) As the results have showed a high correlativity between the needle penetration energy and force, it proves that the dynamic energy produced by the friction of the needle as it penetrates and withdraws from the knitted fabric contributes to the heat growth of the needle. (2) To reduce frictional force the use of thin needles, medium ball point needle and super needle are effective. (3) The reduction in number of plies of fabric or also in the case of a decrease in penetration speed have been effective in lowering the penetration energy and force.

• Journal of the military operations research society of Korea
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• v.24 no.1
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• pp.1-17
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• 1998

우리 군은 창군이래 최대 규모의‘국방개혁추진위원희’를 편성·운영 중에 있다. 차제에 이 글은 군 개혁의 참고모델로서‘이스라엘의 군대’를 제시하여 군 개혁과업을 추진하는데 다소라도 기여하고자 한다. 이스라엘은 지난 50년간‘자주국방’의 정신으로 군사력을 꾸준히 발전시켜서 오늘날 전세계에서 작지만 가장 당찬 정예화군·기술군·과학군을 창조했다. 한국도 지난 50년간‘자구국방’을 위해 부단히 노력한 끝에 이제 외형적으로는 세계 10위권의 큰 군대가 되었다. 그러나, 양국이 지난 50년간 노력하여 만들어 낸 현재의 최종 산출물, 즉 전력수준과 군사태세는 양국의 지닌 저마다의 불가피한 특수한 사정이 있었지만 결과만을 놓고 볼 때는 이스라엘 군이 우리 군보다 우월한 것으로 보여진다. 우리는 우리보다 훨씬 작은 이스라엘이 우리보다 비교 우위의 군사력과 군사태세를 보유하고 있는 이유를 찾아내야 한다. 왜냐하면 그 이유가 곧 우리 군을 개혁해 나가는 데 있어서 참고해야 될 주요 지표가 될 수 있기 때문이다. 이와 같은 관점에서 이 글은 이스라엘의 특수한 안보환경과 건국과정을 살펴본 다음, 이스라엘 군의 특징 및 우수성을 분석하고, 우리 군이 개혁과업을 추진해 나갈 경우 참고될 수 있는 몇 가지 시사점을 개념적 차원에서 제시하였다.

• Journal of the Korean Home Economics Association
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• v.24 no.3
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• pp.59-67
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• 1986

The heat of sewing needle is generated through the friction during the needle penetration into and withdrawal from fabrics. Therefore, effects of sewing condition for knitted fabric on the heat generation of needle was examined. The needle size was not the large influence factor of heat generation of needle but the needle point shape significantly affects needle temperature. And the super needle coated with fluoro resin had more effect on reducing the heat of needle. The decrease of sewing speed and the increase of stitch rate had more effect on the reduction in needle temperature. Also the Influence of a sewing thread on the needle temperature was very large compared with bare needle. As expected, an increase in the number of fabric layers result in higher needle temperature.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.05b
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• pp.79-84
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• 2005

고속철도는 한번에 1천명에 달하는 승객을 태우고 시속 300km를 넘는 고속으로 주행하는 만큼 성능과 안전에 대한 철저한 사전 검증이 필수적이며, 특히 새로운 차량시스템의 개발은 철저한 성능검증 및 안전성을 확보하는 시험평가 과정을 반드시 거쳐야 한다. 본 논문에서는 최고속도 350km/h인 한국형 고속철도 차량시스템 개발사양의 성능요구 조건을 입증하기 위한 시험으로서, 핵심 개발품 단위별 구성품 시험, 개발품 단위간의 조합시험, 차량에서의 기능 동작 확인을 위한 완성차시험(단차시험 및 편성시험)및 전기신호 및 선로구축물 시스템과의 적합성 및 연계성을 확인하는 시운전 시험으로 구분하여 한국형 고속철도 차량시스템의 성능시험 체계 및 성능시험 기준(안)의 개발 내용을 소개하고자 한다.