• Korean journal of applied entomology
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• v.19 no.2 s.43
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• pp.97-101
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• 1980

Present studies were carried out to investigate the life history of potato tuber moth, Phthorimaea operculella (Zeller), under laboratory conditions in Suweon. Studies on its life-cycle on stored potato tubers in the laboratory showed that seven generations were reared in a year and the development from egg to adult was completed in an average of 49.4 days in spring at $18.2^{\circ}C$., 21 days in summer at $26.8^{\circ}C$., 26.1 days at $24.2^{\circ}C$., and 39 days in autumn at $19.6^{\circ}C$. The females laid an average of 101 eggs each, with a maximum of 242 and longevity of adults 17.6 days in spring at $15.1^{\circ}C$., 8.1 days in May-September at $25.3^{\circ}C$., and 13.3 days in autumn at $16.8^{\circ}C$.

• Composites Research
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• v.24 no.1
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• pp.10-16
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• 2011

Many tests are required to predict the fatigue life of composite laminates made of various materials and having different layup sequences. Aiming at reducing the number of tests, a methodology was presented in this paper to predict fatigue life of composite laminates based on fatigue life prediction of constituents, i.e. the fiber, matrix and interface, using micromechanics of failure. For matrix, the equivalent stress model which is generally used for isotropic materials was employed to take care of multi-axial fatigue loading. For fiber, a maximum stress model considering only stress along fiber direction was used. The critical plane model was introduced for the interface of the fiber and matrix, but fatigue life prediction was ignored for the interface since the interface fatigue strength was presumed high enough. The modified Goodman equation was utilized to take into account the mean stress effect. To check the validity of the theory, the fatigue life of three different GFRP laminates, UDT[$90^{\circ}2$], BX[${\pm}45^{\circ}$]S and TX[$0^{\circ}/{\pm}45^{\circ}$]S was examined experimentally. The comparison between predictions and test measurements showed good agreement.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.05a
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• pp.18-21
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• 2009

The life of components under high thermal load is typically shorter than other components. The turbopump turbine of liquid rocket is operated under these environments like high temperature and high centrifugal dorce due to high rotating velocity during operating time. These conditions may often cause low-cycle fatigue problem in the turbopump turbine. First of all, to analyze heat stress, ABAQUS/CAE is used and Coffin-manson's equation is used to consider elasticity and plasticity strain. S.W.T's method is used to consider the mean stress effect, using strain history, low-cycle fatigue analysis is done for turbopump turbine which may have FCL(fracture critical location). In this paper, strain life method is applied to analyze low-cycle fatigue.

• Korean Journal of Materials Research
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• v.10 no.2
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• pp.128-137
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• 2000

A study has been made to investigate the effects of hot isostatic pressing(HIPing) on the microstructure and high temperature fatigue lives of the IN738LC, Ni-base superalloy used in turbine blades, with emphasis on the elimination of casting microporosity and fatigue damage through HIP treatments. Microstructure was observed using OM, SEM and the fatigue life was investigated with rotate bending fatigue tester. The results show that the fatigue lives of properly HIP-processed specimens could be extended be extended by a factor of about sixty. In contrast, no comparable life improvement was achieved with heat treatment only. The repetitive HIP treatment was shown to be very effective as a means of rejuvenating the fatigue life of intentionally fatigue-damaged IN738LC by restoration of the initial alloy microstructure and additional removal of fine casting defects which remained in the HIP-processed material.

• 건강소식
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• v.34 no.12
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• pp.24-25
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• 2010

동의보감을보면 '비인다중풍(肥人多中風)'이라 하여 뚱뚱한 사람이 뇌졸중, 즉 중풍에 더 잘 걸린다고 나와 있다. 뚱뚱한 것도 억울할 판인데 중풍까지 더 잘 맞는다니. 평균수명이 증가하면서 노년을 팔팔하게 보내는 노인들이 많은 요즘, 억울해서라도 비만에서 탈출해야 할 듯하다. 왜 뚱뚱하면 중풍에 잘 걸리는지 그 이유를 알아본다.

• Ceramist
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• v.7 no.1
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• pp.21-29
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• 2004

인류의 평균수명이 지속적으로 연장되고 삶의 질을 향상시키려는 욕구가 증가함에 따라 고급 의료기술에 관한 관심이 크게 증가하고 있다. 기존에는 치아가 결손되었을 때 브릿지라는 보철물이나 틀니를 사용하였으나 인접 치아 및 잇몸에 손상을 주는 부작용이 있었다. 최근 널리 보급되고 있는 임플란트 시술법은 결손된 치아 자리에 인공치아를 심는 방법으로서, 치아가 소실된 부분에 치아뿌리 모양의 임플란트를 매식하여 턱뼈에 고정시킨 후 여기에 크라운을 연결하여 보철을 완성한다.(중략)

• 건강소식
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• v.32 no.7
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• pp.4-5
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• 2008

오래 사는 것 보다 건강을 유지하며 사는 것을 더욱 중요시하는 시대에 한국인이 가장 조심해야 할 질병은 암. 우리나라 국민들이 평균수명까지 생존할 경우 암에 걸릴 확률은 남자 27.7%, 여자 22.2%로 국민 3명 당 1명은 암에 걸릴 수 있다. 그러나 암은 금연, 균형 잡힌 식단, 꾸준한 운동 등 생활 습관을 올바르게 유지함으로써 예방 할 수 있고, 초기에 발견하면 치료 확률도 높다.

• 한국상하수도협회지
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• s.24
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• pp.44-45
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• 2008

세계인의 평균수명 증가에는 의료기술의 발달이 큰 몫을 했다. 하지만 수도시설의 보급 역시 적지 않은 영향을 미쳤다고 볼 수 있다. '블루 골드(Blue Gold)' 시대를 맞아 각국의 수돗물 서비스의 수준이 곧 국가경쟁력으로 이어지고 있는 시점에서 수도산업을 공고히 하기 위한 국가 차원의 노력이 필요한 때이다.

• The Monthly Diabetes
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• s.238
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• pp.10-13
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• 2009

대부분의 당뇨병성 합병증은 혈관을 매개로 진행되며, 당뇨병성 혈관질환은 당뇨병환자의 가장 흔한 사망 원인이다. 당뇨병의 관리가 개선되면서 당뇨병환자의 평균수명은 크게 늘어났는데, 혈관질환의 발생 위험성은 시간이 지나면서 자연적인 노화현상과 함께 점점 더 커지므로, 제대로 된 당뇨병의 관리는 혈당 조절 그 자체뿐 아니라 혈관의 손상을 억제하는 노력이 반드시 포함되어야 한다.

• Proceedings of the Optical Society of Korea Conference
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• 2009.10a
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• pp.199-200
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• 2009