• Composites Research
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• v.23 no.5
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• pp.22-29
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• 2010

This paper describes the evaluations of tension-compression fatigue characteristics and life for glass fiber/epoxy laminate composite applied to railway bogie to reduce weight. Test samples of tension-compression fatigue were composed of glass fiber/epoxy 4-harness woven laminate composites with different stacking sequence of warp-direction, fill-direction and ${\pm}45^{\circ}$-direction. The tension-compression fatigue test was conducted with stress ratio (R) of -1 and frequency of 5Hz. Goodman diagram were used to evaluate the fatigue characteristics and life of glass fiber/epoxy 4-harness satin woven laminate composite. Anti-buckling jig was designed to prevent buckling of specimen under compression load. The test results showed that the fatigue characteristics of glass fiber/epoxy 4-harness satin woven laminate composite with stacking sequence of warp-direction had a good performance in comparison with that of SM490 used to conventional metal railway bogie.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.9
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• pp.18-25
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• 2003

In this paper, thermal conductivities of carbon-phenolic 8-harness satin weave composite, ACP302, were measured and predicted. In the analysis, the satin weave unit cell was identified and modeled discretely by 3-dimensional finite elements, considering the interlaced fiber tow architecture microscopically. At the unit cell boundary, the corresponding periodic boundary conditions were applied. The results were analyzed to investigate the effect of microstructural parameters such as stacking phase shifts, waviness ratio, and fiber volume fraction. The conductivities were also obtained by experiments and compared with the numerical results.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2003.04a
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• pp.50-52
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• 2003

The purpose of this study is to measure the thermal conductivity of a carbon/phenolic 8-harness woven composite. An experiment apparatus and procedure developed in the previous study were used to measure the thermal conductivities. This method compares the temperature difference between a reference specimen with a known thermal conductivity and the test sample specimen in a steady-state condition.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.14 no.4
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• pp.455-467
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• 2001

In this study, the stacking phase shift effect on the effective property and stress distribution was investigated for 8-harness satin weave textile composites under uni-axial tension. Textile configurations with varied phase shifts were modeled by unit cells and repeating boundary conditions were applied at the outer periodic surfaces. The effective property and stress were calculated by the unit cell analysis using macro-element to reduce the computational resource. It was found that stresses were dependent on the variation of tow arrangement of adjacent layers. The in-phase and the shifted configurations showed large differences in the stress distribution pattern. The stress level was very high in the resin region and the distribution of the maximum stresses was widely scattered.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.7
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• pp.41-52
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• 2003

In this paper, three-dimensional thermo-mechanical properties of carbon-phenolic 8-hamess satin weave composites were predicted considering geometric parameters of microstructures. The effective properties were calculated by a series of numerical experiments based on unit cell analysis. The microstructural details were modeled through macro-elements, and the periodic boundary conditions were derived for corresponding un it cell types. The Monte Carlo method was employed to consider the random phase shift between the layers, and the results were investigated on the effect of the geometric parameters of shift, number of layers and waviness ratios. Experimental tests were also performed and the results were compared.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.8
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• pp.913-920
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• 2011

We describe the evaluation of the fatigue life and strength of a lightweight railway bogie frame made of glass fiber/epoxy 4-harness satin-woven composites. To obtain the S-N curve for the evaluation of the fatigue characteristics of the composite bogie frame, we performed a tension-compression fatigue test for composite specimens with different stacking sequences of the warp direction, fill direction, and $0^{\circ}/90^^{\circ}$ direction. We used a stress ratio (R) of -1, a frequency of 5 Hz, and an endurance limit of $10^7$. The fatigue strength of the composite bogie frame was evaluated by a Goodman diagram according to JIS E 4207. The results show that the fatigue life and strength of the lightweight composite bogie satisfy the requirements of JIS E 4207. Given its weight, its performance was better than that of a conventional metal bogie frame based on an SM490A steel material.

• Journal of the Korean Society for Railway
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• v.16 no.1
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• pp.1-6
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• 2013

In this study, the natural frequency and damping ratio of a four-harness satin woven glass/epoxy composite material are evaluated by means of modal tests and a finite element analysis. To achieve this goal, glass/epoxy beam specimens with different lengths and thicknesses were manufactured via autoclave curing. In the test, the maximum damping ratio was found to occur at the lowest test frequency. As the test frequency increased, the damping ratio decreased exponentially to a critical value. After that value, the damping ratio increased gradually to the maximum test frequency.

• Journal of Sericultural and Entomological Science
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• v.24 no.1
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• pp.39-41
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• 1982

1981년에 견직물 Wash and Wear가공 연구를 국제견업협회(I.S.A) 기술분과위원회에서 발표하였든바 의외로 지대한 관심을 보였는데, 금년초 동협회로부터 8개 종류의 견직물을 송부해와 본 연구의 재확인을 하고싶다 하여 기왕이면 방추성도 향상시키는 실험을 해야 되겠다고 결정하고 본 연구에 착수하였다. 본 연구는 따라서 1982년 I.S.A회의에서 다시 발표하게끔 되어 있다. 본 연구로 얻어진 결과는 다음과 같이 요약할 수 있었다. 1. 수지가공으로 방추성이 나쁜 견직물은 20%정도 향상시킬 수 있었다. 2. 수지가공과 Wash and Wear가공을 단일공정으로 해도 Wash and Wear효과가 있었다. 3. 본래 견직물이 고밀도직으로 되었거나 고연견직일 때는 방추성이 본래 좋아서 수지가공을 해도 수％ 밖에 향상되지 못하였다. 4. 견직물조직면으로 볼 때 주자직이나 능직이 평직보다 좋은 방추성을 보였다. 5. 본 연구처리는 염색물의 염색 견뢰도를 향상시키는 효과도 있었다.

• (The)Study of the Eastern Classic
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• no.59
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• pp.213-231
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• 2015

양송(兩宋) 교체기의 중요한 시인이자 비평가인 주자지(周紫芝)의 "죽파시화(竹坡詩話)"는 당시의 여느 시화와 마찬가지로 각 조 사이의 관계가 전혀 유기적이지 않으며 주제도 천차만별이다. 하지만 그 안에 도연명(陶淵明), 두보(杜甫), 이백(李白), 한유(韓愈), 류종원(柳宗元) 등의 당대(唐代) 시인부터 소식(蘇軾), 황정견(黃庭堅), 매요신(梅堯臣), 장뢰(張?) 같은 송대(宋代) 시인에 이르기까지 직, 간접적으로 언급된 시인이 40여 명이나 되고 그들의 작품에 대한 평가와 격률(格律), 자구(字句), 용사(用事)에 대한 분석 및 고증, 그리고 주자지 개인의 시론이 단문 형태로 흩어져 있다. 하지만 그것들을 종합, 개괄하면 주자지의 심오하고 독창적인, 시의 격식과 내용을 함께 존중하는 시학(詩學)을 확인할 수 있다. 그러나 "죽파시화"는, 본래 주자지가 이른바 '남도시단(南渡詩壇)'의 주요 시인이었기 때문에 상대적으로 시 이외의 기타 저작이 홀시되었고 그의 스승이 장뢰(張?), 이지의(李之儀)였던 사실로부터 그의 시학 역시 강서시파(江西詩派)를 답습했을 것이라는 판단이 미리 내려진 탓에 지금까지 시문학사에서 온당한 평가를 받지 못했다. 하지만 주자지는 "죽파시화"에서 당시 형식과 기교에 편중했던 강서시파 말류의 병폐를 명확히 인식하여 독자적으로 자연스러움과 조탁을 고도로 통일시킨 시학을 제시하였다. 요컨대 기계적인 모방 이론에 반대하고 평담(平淡), 자연(自然), 청원(淸遠)의 풍격을 추구하는 한편, 연구(煉句), 연자(煉字)에 힘씀으로써 오히려 평담함의 시풍에 이르게 된다고 하였다. 주자지의 이런 시학은 중국 시문학사에서 그 지위를 재평가 받아야 하며, 아울러 송대뿐만 아니라 오늘날에도 시인과 평론가들이 참고할 만한 보편적 가치를 가졌다.

• Korean Journal of Heritage: History & Science
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• v.19
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• pp.1-11
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• 1986