• Proceedings of the Korean Fiber Society Conference
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• 1998.10a
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• pp.386-389
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• 1998

일반적으로 폴리에스테르 필라멘트에 집속성과 제직공정에서 요구되는 강도 등을 만족시키기 위해 2-for-1 연사기에 의해 꼬임을 주게 된다. 그리고 이 꼬임을 고정시키기 위해 진공세팅기로 열처리를 함으로써 연을 안정화시키게 된다 이때 실린더 내외층간의 온도분포가 균일하지 못함으로 인해 사의 물성이 달라지게 된다. 이로 인하여 염ㆍ가공 공정 후에 직물에 경사나 위사방향으로 선이 보이는 streaks현상, 직물 좌우의 색차 등의 불량을 유발하게 된다. (중략)

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.63-63
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• 2004

구동 및 동력 전달용으로 많이 쓰이는 기어장치는 최근 고속도비에서 사용이 증가함에 따라 다단기어장치의 설계에 대한 관심이 높아지고 있다. 하지만 다단 기어장치의 설계는 장치의 파손확률을 고려하지 않고 정적인 하중과 균일한 강도를 유지하는 차원에서 접촉해석과 강도설계 등이 주류를 이루었으며 대부분 설계자의 경험과 감각에 의해 시행착오적이고 반복적인 방식으로 이루어지고 있다. 또한 임의의 시간에서 다단 기어장치가 설계자의 의도대로 작동할 확률인 신뢰성에 대한 연구가 미흡하였다.(중략)

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2014.11a
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• pp.75-76
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• 2014

Copper는 2차 전지 및 PCB 등 Electrical Device에 빠짐없이 들어가는 핵심 부품이다. 반도체 배선재료 또한 Aluminum에서 Copper로 대체되어 Electrical Conductivity 및 Electro-migration 문제를 해결할 수 있었다. 최근 배선의 미세화 및 전지용량 증가로 인해 보다 얇으면서, 동시에 높은 기계적 강도를 가지는 Copper Film의 필요성이 요구되고 있다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1995.11a
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• pp.181-191
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• 1995

Al 7175 합금 형단조에서 주조조직 파괴를 위한 빌렛트제작(BM)공정과 ITMT공정 이 기계적 성질에 미치는 영향을 조사하였다. BM공정과 ITMT 공정을 동시 적용한 형단조품의 기계적 성질은 길이방향에서 인장강도가 10%, 연성이 50%, 충격흡수 에너지가 20% 증가되었고 횡방향에서도 인장강도가 7%, 연성이 9% 증가되었다. 이와 같은 기계적 성질의 향상은 BM과 ITMT공정을 동시 적용한 형단조품 미세조직의 결정립크기가 17$\mu\textrm{m}$로서 일반단조조직보다 3배이상 미세하고, 균일한 등축재결정 조직을 나타내는데 기인하는 것으로 판단된다.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.2
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• pp.51-58
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• 2008

This study is to investigate the ultimate shear load of prestressed girder made of Ultra High Performance Fiber Reinforced Concrete (UHPFRC). Nine girders were tested until failure in shear. An analytical model to predict the ultimate shear load was formulated based on the Two Bounds Theory. A fiber reinforcing model was constituted based on the random assumption of steel fiber uniform distribution. The predicted values were compared with the conventional predictions and the test results. The proposed equations for computing the ultimate shear strength can be used for the ultimate failure status analysis, which could also be utilized for numerical limit analysis of prestressed UHPFRC girder. The established fiber reinforcing theoretical model can also be a reference for micro-mechanics analysis of UHPFRC.

• Progress in Medical Physics
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• v.23 no.4
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• pp.269-278
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• 2012

Aquaplast Thermoplastic (AT) is a tissue-equivalent oral compensator that has been developed to improve dose uniformity at the common boundary and around the treated area during radiotherapy in patients with head and neck cancer. In order to assess the usefulness of AT, the degree of improvement in dose distribution and physical properties were compared to those of oral compensators made using paraffin, alginate, and putty, which are materials conventionally used in dental imprinting. To assess the physical properties, strength evaluations (compression and drop evaluations) and natural deformation evaluations (volume change over time) were performed; a Gafchromic EBT2 film and a glass dosimeter inserted into a developed phantom for dose verification were used to measure the common boundary dose and the beam profile to assess the dose delivery. When the natural deformation of the oral compensators was assessed over a two-month period, alginate exhibited a maximum of 80% change in volume from moisture evaporation, while the remaining tissue-equivalent properties, including those of AT, showed a change in volume that was less than 3%. In a free-fall test at a height of 1.5 m (repeated 5 times as a strength evaluation), paraffin was easily damaged by the impact, but AT exhibited no damage from the fall. In compressive strength testing, AT was not destroyed even at 8 times the force needed for paraffin. In dose verification using a glass dosimeter, the results showed that in a single test, the tissue-equivalent (about 80 Hounsfield Units [HU]) AT delivered about 4.9% lower surface dose in terms of delivery of an output coefficient (monitor unit), which was 4% lower than putty and exhibited a value of about 1,000 HU or higher during a dose delivery of the same formulation. In addition, when the incident direction of the beam was used as a reference, the uniformity of the dose, as assessed from the beam profile at the boundary after passing through the oral compensators, was 11.41, 3.98, and 4.30 for air, AT, and putty, respectively. The AT oral compensator had a higher strength and lower probability of material transformation than the oral compensators conventionally used as a tissue-equivalent material, and a uniform dose distribution was successfully formed at the boundary and surrounding area including the mouth. It was also possible to deliver a uniformly formulated dose and reduce the skin dose delivery.

• Journal of Korean Society of Steel Construction
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• v.30 no.1
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• pp.1-12
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• 2018

A curved member should resist bending and torsional moments simultaneously even though the primary load is usually supposed to be gravitational load. The torsional moment causes complicate stress state and also can result in early yielding of material to reduce member strength. According to analysis results, the strength of a curved member that has 45 degrees of subtended angle could decrease more than 50% compare to straight girder. Nevertheless, there have been very few of researches related with ultimate strength of curved girders. In this study, various kinds of stiffness about bending, pure torsion and warping were considered with a number of models in order to verify the main factor that affects ultimate behavior of curved girder. Lateral and rotational displacement of curved member were introduced as lateral-torsional-vertical behavior and bending-torsional moment interaction curve was derived. Finally, a strength equation for ultimate moment of horizontally curved steel I-girders subjected to equal end moments based on the interaction curves. The equation could take account of the effect of curvature, unbraced length and sectional properties.

• Korean journal of applied entomology
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• v.34 no.4
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• pp.368-372
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• 1995

To develop a microbial pesticide for the control of pine gall midges. Thecodiplosis japonensis, entomopathogenc fungi were isolated from 233 soil samples in the damaged region of Thecodiplosis japonenesis, and identified with Beauveria spp. 29 strains and Paecilomyces spp. 2 strains. The morphology of entomopathogenic fungi was observed by scanning electron miroscope. In addition, the toxicity of entomopathogenic fungi was observed by scanning electron microscope. In addition, the toxicity of entomopathogenic fungi isolated from soil samples was determined by bioassay against Thecodiplosis japonensis larvae. The result showed that toxicity of relatively pathogenic strains, Beauveria spp. SFB-168-2 was 82.9%, suggesting that Beauveria spp. SFB-168-2 is effective entomopathogenic fungi for the control of pine gall midges.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1979.10a
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• pp.243.2-243
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• 1979

현재 우리나라의 탁약주 용 Rice-Koji 제조 용종국균으로 널리 분양되고 있는 분양되고 있는 fawachi, S-27 균주가 생성하는 Amylase의 효소학적 특성과 Rice-Koji i제조 시 유기산 및 당화 효소의 생성 조건을 검토했다. 1. 본 균은 유기산 생성력이 강하고 또 생성하는 당화효소 및 액화효소는 내산성이 극히 강하며 pH3~5의 범위내에서 최고 활성을 나타내었으므로 탁약주 제조 용 종국균으로 아주 적합하였다. 2. 본 균의 발아 최적온도는 36$^{\circ}C$이었으며 Rice -Koji제조시 제국시간을 40시간으로 볼 때 유기산 생성의 최적온도는 32$^{\circ}C$이었고 당화효소 생성의 최적온도는 36$^{\circ}C$이었으며 고온인 4$0^{\circ}C$에서는 유기산 생성이 극히 불량하였다. 3. Rice-Kojiw제조시 당화효소의 생성은 배지의 수분함량 35%일 때 최고치를 보였으며 유기산 생성은 이 보다 높은 조건인 수분함량 40%일 때 이었고 비교적 건조한 조건인 수분함량 30%일 때는 유기산 생성이 특히 불량하였다. 4. 배지의 두께가 3cm이상이 되면 유기산 및 당화효소 생성에 않은 지장을 주었다. 5. 종국균의 점종량은 유기산 및 당화효소의 생성에 별로 영향을 미치지 못했다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.187-190
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• 2002

Confocal microscopy is very popular technology in bio-medical inspection due to its ability to reject background signals and to measure very thin slide of thick specimens, which is called optical sectioning. But intensity of detected signal in fluorescence type confocal microscopy is so small that only 0.2% of emitted fluorescence light can be detected in the best case. In this paper, we proposed the reflecting optical system to improve the detection intensity and designed the optical system by optimal design method. At the end of the paper, we analyzed the characteristics of the proposed reflecting optical system.