• 한국생산제조학회지
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• 제7권6호
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• pp.117-125
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• 1998

The paper attempts to estimate the incubation time of a cavity in the interface between a power law creep particle and an elastic matrix subjected to a uniaxial stress. Since the power law creep particle is time dependent, the stresses in the interface relax. The volume free energy associated with Helmholtz free energy includes strain energies caused by applied stress and dislocations piled up in interface(DPI). The energy due to DPI is found by modifying the result of Dundurs and Mura[4]. The volume free energies caused by both applied stress and DPI are a function of the cavity size(r) and elapsed time(t) and arise from stress relaxation in the interface. Critical radius $r^*$ and incubation time $t^*$ to maximise Helmholtz free energy is found in present analysis. Also, kinetics of cavity formation are investigated using the results obtained by Riede [7]. The incubation time is defined in the analysis as the time required to satisfy both the thermodynamic and kinetic conditions. Through the analysis it is found that 1) strain energy caused by the applied stress does not contribute significantly to the thermodynamic and kinetic conditions of a cavity formation, 2) in order to satisfy both thermodynamic and kinetic conditions, critical radius $r^*$ decreases or holds constant with increase of the time until the kinetic condition(eq. 2.3) is satisfied. there for the cavity may not grow right after it is formed, as postulated by Harris [15], and Ishida and Mclean [16], 3) the effects of strain rate exponent (m), material constant $\sigma$0, volume fraction of the particle to matrix(f)and particle size on the incubation time are estimated using material constants of the copper as matrix.

• 한국버섯학회지
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• 제16권2호
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• pp.61-64
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• 2018

This study was carried out to investigate the management characteristics and growth performance of L. edodes from the cooling stage to incubation. Bags of different heights and weights are available for bagging. When the medium size of $17{\times}13cm$ was used and the size of the inoculation hole was changed from 1/3 to 2/3, the browning period was shortened to 30 days. Mycelial growth was evaluated according to the cooling temperature after sterilization. It was observed to be the highest at 122 mm/15 days at $10^{\circ}C$ and 114 mm/15 days and 117 mm/15 days at $15^{\circ}C$ and $20^{\circ}C$, respectively. The contamination rate of the sawdust media before inoculation was measured as 0, $4.5{\times}10$, $1.3{\times}10^2$, $4.0{\times}10^3cfu$ at $5^{\circ}C$, $10^{\circ}C$, $15^{\circ}C$, and $24^{\circ}C$ respectively. The average of $1.6{\times}10^8$ colony forming units (cfu) of microorganisms was observed in the sawdust that had been piled for six months outdoors. In summer, the sawdust has to be used immediately after mixing. The sterilized medium had an average of $4{\times}10^3cfu$ of microorganisms at $24^{\circ}C$ and $1.3{\times}10^2cfu$ at $15^{\circ}C$. After 15 days of inoculation in vitro, the growth conditions of the sawdust was the best at 132 mm, followed by grain and liquid. When inoculated with liquid spawn, the moisture content of the substrate should be adjusted between 50% and 55% in advance.

• 동의생리병리학회지
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• 제18권4호
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• pp.965-975
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• 2004

The writer reviewed on Chojop and came to conclusions as follows. Symptoms of Chojop is appeared digestive ailment such as belching, nausea, regurgitation of acid, stomachache etc., if being serious, felt oppressed with palpitating in chest and uneasiness at times. In Dangaesimbub written by Chujinhyung, the causes of Chojop were mainly regarded as phlegmatic fire(痰火) and suggested the way of treatment. The causes of Chojop are movable fire with phlegm, insufficiency of blood caused by thinking to excess, and Shinyanghohan(腎陽虛汗) that is piled cold phlegm by voidance and coldness of Renal Yang, but the main cause is brought to a conclusion as phlegmatic fire. The phlegmatic fire is come from being in discord with the spleen and the stomach, or from in harmony between vigor and blood according to essence and vital energy which are disturbed by combined feelings. That is caused by disharmony between inner and outer conditions according to individuals. The distinctive features in shapes of Chojop are revealed to shapes such as manlike woman, womanlike man, wearing darkish or reddish color between two eyebrows, being almond eyed, strong eyebrows, being sunk the upper part of the nose bridge, lots of facial blots, Dam-body, Ki type, Shin type, Birds group, and Yangmyung type. The doctors can prescribe Whadamchungwhatang to Yangmyung type, Yanghyulsamul-tang for patients with strong eyebrows so flourishing blood and vigor, Hyangsapyungwuisan for patients belong to Birds group, Soshikchungul-tang for Ki type, and Palmiwhan for man belonged to Bangkwang-body with voidance and coldness of Renal Yang chiefly.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 춘계학술대회 논문집
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• pp.478-482
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• 2002

Recently, the demand for the optical cable is rapidly glowing because the number of internet user increases and high speed internet data transmission is required. To meet this demand, it is necessary to have a sufficient manufacturing capability for mass and high-quality production. But the present optical cable winding system has some serious problems such that the optical cable of radius (6 mm -40 mm) is often piled up and collapsed usually at the edge of the bobbin in the process of the cable winding. It is often necessary to have an additional operator in order to adjust the cable, which causes the productivity decrease. In order to improve a performance of cable winding system which deals with relatively thick cable( radius : 6 mm -40 mm ), we developed a new guiding system for a high-speed self-align cable winding. First of all, the winding mechanism was analyzed. Synchronization logics for the motions of winding, traversing, and the guiding were created and implemented by using the PLC and guiding system controller in a prototype cable winding system manufactured in the CILS( Computer Integrated Large scale System ) lab. An experimental verification was carried out to validate the logic. Results showed that the winding system with the developed guiding system outperformed in reducing pile-up and collapse in the high-speed winding(up to 300 mm/s) compared with the system without the guiding system.

• 멤브레인
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• 제24권5호
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• pp.393-399
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• 2014

본 연구에서는 디스크 링 형태에 패터닝된 박막을 적층시킨 모듈의 분리특성을 규명하고자 투과실험을 수행하였다. 먼저, 본 연구에서 자체 제작한 5가지 형태의 디스크 필터의 순수 투과도를 측정하였으며 그 값은 0.25 내지 $2.24L/m^2{\cdot}hr{\cdot}bar$이었다. 0.1 wt% 카올린 수용액을 투과시키면 순수 투과율이 가장 높은 모듈의 투과유속이 가장 높았고, 순수 투과율이 가장 낮았던 모듈의 카올린 투과유속이 가장 낮게 나타났다. 그러나 모든 모듈의 카올린 투과유속이 순수 투과율에 비례하지는 않았다. 또한 0.1 wt% 수용액으로 장시간 운전하기 위하여 디스크 필터 모듈 1에 주기적으로 역세척을 실시하였으며 가장 효율적인 운전조건은 투과시간 8분, 역세척 2분 주기임을 확인하였다.

• 한국광물학회지
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• 제21권3호
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• pp.297-305
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• 2008

의성 옥동광산에 적치되어 있는 광미는 미세분말로 이루어져 있으며, 주 구성광물은 황철석, 섬아연석, 녹니석, 일라이트, 사장석, 스멕타이트, 석고 등이다. 점토광물 중 스멕타이트는 광미 적치장 상부에 집중되어 있고 하부로 갈수록 녹니석이 증가한다. 석고는 광미 적치장 표면에 주로 나타나는데 이는 광미와 반응한 침출수가 증발하면서 침출수에 포함된 Ca와 $SO_4$가 반응하여 침전된 증발잔류물로 추정된다. 전자현미경 관찰 결과 광미에 포함된 섬아연석은 표면뿐만 아니라 내부까지 풍화되어 있는 것으로 보아 오랜 시간동안 지하수와 반응하여 다량의 Zn과 $SO_4$를 침출수에 부가되었을 것으로 추정된다.

• 보존과학회지
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• 제32권3호
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• pp.437-448
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• 2016

전지구적으로 일어나는 기후변화에 대응하기 위해 20세기 말부터 선진국을 중심으로 기후변화에 의한 문화유산 취약성 평가와 대책 연구가 활발히 이루어져 관련 연구방법이 정립되고 방대한 기후자료와 손상예측 자료가 축적되었다. 우리나라는 관련된 정책연구가 다수 수행된 반면 여전히 과학적인 근거자료를 확보해야 하는 당면 과제가 남아있다. 한반도 미래 기후자료를 반영한 국내 석조유산의 미래 손상양상은 물리적, 화학적 및 생물학적 풍화 측면에서 복합적으로 변화할 가능성이 높으며, 이는 문화유산 보존 분야의 산업과 행정관리에도 영향을 미칠 것으로 전망된다. 앞으로 기후변화에 의한 석조유산의 영향 연구는 지역과 자료주기의 다운스케일을 통해 정밀화된 방향으로 진행되어야 한다. 이를 통해 손상유형과 지역별로 미래 환경에 취약한 석조유산을 가려내고 대응방안을 마련하는 것이 필요하다.

• 에너지공학
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• 제22권2호
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• pp.148-155
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• 2013

한국표준형원전(OPR-1000)의 증기발생기 전열관은 관재료로 Alloy 600과 Alloy 690이 사용되고 있으며 전열관 확관방법은 폭발확관법이 적용되었다. 원전 운전경험에 따르면 전열관 확관법으로 폭발확관법이 사용된 증기발생기의 전열관들은 원주방향 균열이 잘 발생하였으며 그 위치는 전열관의 확관천이부위 외면이었고 슬러지에 의해 둘러싸인 지역이었다. 그러나 같은 조건의 전열관이라도 수압확관법이 적용된 경우는 원주방향 균열보다는 축방향 균열이 우세한 경향을 보여왔다. 따라서 본 연구에서는 상기와 같은 차이를 규명하기 위하여 전열관과 관판의 형상을 모델링하였으며 확관법에 따라 운전중 조건에서 전열관의 확관천이 부위에 작용하는 응력의 크기를 전산프로그램을 사용하여 계산하였고, 균열의 방향성과 우세성을 평가하였다.

• 아시안잔디학회지
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• 제13권2호
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• pp.101-112
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• 1999

Four major scarab beetles, Ectinohoplia rufipes, Adoretus tenuimaculatus, Exomala orientalis and Popillia quadriguttata were obserbved in golf courses. Morphological characters of adults and larvae, feeding habit, mounds by grubs, and outbreak time were inbestigated. Body lengths of E. rufipes and A. tenuimaculatus were 11.5mm and 9.7-11.3mm, respectively and those of E. orientalis and P. quadriguttata were 8.0-13.5mm and 7.6-12.7mm, respectively. Adult of E. rufipes had a tendency to raise hind legs during the feeding and mating but showed no death feigning. On the contrary, A. tenuimaculatus adult did not raise its hind legs during the feding and showed death feigning and dropped to earth when disturbed. E. orientalis adults were mainly found from the flowers of chestnut trees in the daytime and P. quadriguttata adults were chiefly found from soft leaves of herbaceous plants in golf courses. White grubs of E. rufipes and A. tenuimaculatus did not have longitudinal and transversal seatae on anal part but setae on the raster were hooked. The shape of anal slit was Y-shape in E. rufipes and crescent-shape in A. tenuimaculatus. White grubs of E. orientalis had ten to sixteen longitudinal setae on raster and those of P. quadriguttata had medially two conspicuous rows of six or seven shorter straight setae forming a V. Adults of E. rufipes mainly fed on front part of leaves but those of A. tenuimaculatus fed on hind part of leaves. Mounds by earthworms and white grubs were different depending on species. Earthworm piled up sticky soil around exit hole but E. orientalis adult scattered soil one part of exit hole and A. tenuimaculatus adult scattered soil evenly around exit hole. Outbreak time of E. rufipes and A. tenuimaculatus was early May and that of E. orientalis and P. quadriguttata was late May.

• 지능정보연구
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• 제12권3호
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• pp.33-46
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• 2006

물류의 증가로 생산된 제품이 소비자에게 전달되기 전 저장하는 제품 창고의 운영과 유지는 제품원가의 큰 부분을 차지하게 되었다. 취급작업 횟수의 감소, 신속한 출고 작업, 제품의 효율적 관리를 위해 저장설비의 설치, 저장 공간의 추가 확보 등의 시설 투자 방법으로도 이런 문제를 해결 할 수 있지만 기존 저장 공간을 최대한 활용함으로써 취급작업 수를 줄일 수 있다. 저장시설 내에서의 운영방법에는 여러 가지가 있겠지만 저장 공간의 제약이 있기 때문에 제품을 겹쳐 쌓아야 하고 그 경우 반드시 재취급을 고려해야 한다. 재취급 문제는 창고의 취급 효율을 결정짓는 가장 중요한 문제이다. 따라서 창고의 운영 효율을 높이기 위해서는 재취급을 최소화할 수 있는 방법을 고려할 필요가 있다. 본 연구에서는 기대 재취급을 최소화하는 혼적결정 문제를 다루고자 한다. 혼적결정을 위한 최적화 모형을 제시하였고 해를 구하기 위한 유전자 알고리즘을 제시하였다. 이 연구결과는 컨테이너 터미널을 포함하여 재취급이 발생할 수 있는 창고의 운영에 활용될 수 있다.