• 한국구조물진단유지관리공학회 논문집
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• 제20권1호
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• pp.118-125
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• 2016

현재 대형 빌딩이나 공동주택에 건설되는 지하구조물은 건조수축, 시공이음, 폼타이부 등에서 콘크리트 균열로 인한 누수가 많이 발생되고 있다. 누수가 발생하게 되면 구조물의 지하공간은 결로, 곰팡이 등이 발생되어 지하 환경을 악화시키고 구조물의 콘크리트로 흡수되면 철근의 부식 등을 유발하여 구조물의 안전을 위협한다. 이는 지하구조물의 사용과정에서 장기적인 쾌적성과 구조물에 안전성이 고려되지 않은 설계와 시공의 결과이며 누수 하자에 대하여 유도배수처리로 대응하기 때문에 근본적인 누수보수가 이루어지지 않아 지하구조물은 항시 누수를 허용하고 있는 실정이다. 따라서 본 연구에서는 지하에 적용되는 방수공법을 내방수와 외방수로 분류하고 이를 바탕으로 지하구조물과 유사한 간이시험체를 제작하였으며, 결로가 많이 발생되는 동절기의 온도조건을 기준으로 지하환경의 방수공법별 습도변화량을 분석할 것이다.

• 보존과학연구
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• 통권19호
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• pp.75-107
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• 1998

The cultural properties of paper made from 11 to 16th century of the Kirimsa temple were found in Birozana Buddhist Statue which was made from 15 to 16th century. These have been stored and exhibited in the exhibition showcase. To examine the environment of conservation and the state of paper, we investigated the temperature and the relative humidity in the inside and outside of the Kirimsa museum and examined the external form and the internal state (water content, acidity and whiteness) of paper. During the investigation period from 27 Aug. to 30 Aug. 1997. The average of temperature and relative humidity were $28.2^{\circ}C$, 67% in the outside and $27.1^{\circ}C$, 73% in the inside, respectively. These indicated the air conditioning was wrong. Among the cultural properties of 79 papers stored in the Kirimsa museum, 37 cases had been repaired but 42 cases not. From the result examining the external form, 20 cases needed to repair. In the internal state of the cultural properties of paper, the water contents were from 11.9% to 16.5%, the average was 15.7%, the acidities from pH 5.7 to pH 6.2 and the whiteness from 37 to 45. From these results, we could see the cultural properties of paper stored in the Kirimsa museum was damaged by the several factors (hydrolysis by fungi, repeated elongation and retraction of cellulose) caused mainly by the high temperature and relative humidity. Therefore, for the conservation of the cultural properties of paper stored in the Kirimsa museum, it need to control the temperature at $18~20^{\circ}C$ and the relative humidity at $55\pm5%$ by the appropriate air conditioning. In order to sterilize fungi occurred to the surface of paper, the cultural properties of paper needed to fumigate. The fungi occurred on the surface of paper were wiped out by using of 70%solution dissolved thymol in ethyl alcohol.

• 한국식품과학회지
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• 제28권1호
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• pp.72-76
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• 1996

표고버섯의 건조공정에 큰 영향을 미치는 열풍의 온도, 습도 및 수분감량 등의 요인을 제어할 수 있는 마이크로 컴퓨터 제어 시스템을 이용하여 버섯류의 건조특성과 기작을 구명하고, 건조제품의 이화학적 특성을 측정하였다. 표고버섯의 열풍건조중 수분이동은 Page Model을 따랐으며, $50^{\circ}C$의 건조온도와 20% 상대습도의 건조조건에서 건조시의 관계식은 $M-M_c/M_0-M_c\;=\;\exp\;(-0.275t^{1.154})$였다. 건조된 표고버섯의 아미노산 함량은 상대습도를 증가시킴에 따라서 증가하였다. 그리고 색도 및 갈변도는 건조온도와 상대습도가 증가할수록 증가하였으며, 복원률은 건조온도와 상대습도가 낮을수록 증가하였다.

• 한국작물학회지
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• 제42권4호
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• pp.473-482
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• 1997

Temperature, humidity and wetness duration were monitored for fully developed paddy rice canopies with 3 different structures induced by the seeding method(puddled-soil drill seeding, DS ; hand broadcasting, HB ; machine broadcasting, MB). Within-canopy air temperature averaged over "clear sky" hours during the study period(maximum tillering through heading) was lower than the screen temperature at a nearby standard weather station, especially in the night. The same trend was true for "overcast sky" hours except the diurnal distinction. Vapor pressure within the canopy was high during the daytime and low in the night, making the daytime deviation from outside the canopy more significant on clear days. Under the overcast sky, the canopy maintained a steady 5 to 10％ higher vapor pressure than the outside regardless of day or night. Daily maximum temperature was observed to be higher within the canopies with more leaf mass, making MB the highest, HB the lowest, and DS in between. Relative humidity was over 90％ in the night and dropped to 70％ in the mid-afternoon, but vapor pressure within the canopy was highest at around 13:00 LST. Dew point depression was lowest and, combined with the temperature, the relative humidity was highest in HB. Mean period of wetting duration was in the order of DS＞HB＞MB, while the dew point depression was greatest in DS.

• International Journal of Industrial Entomology and Biomaterials
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• 제8권1호
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• pp.27-32
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• 2004

With an objective of evolving quantitatively and qualitatively superior bivolitine silkworm hybrid of Bombyxmori L. for tropics with shorter larval duration without compromising on productivity traits, a breeding programme was initiated at this institute during 1997 by utilizing breeding resource material from the institutes Germplasm collection. The breed SD7 is characterized with plain larvae spinning white oval cocoons and SD12 is characterized by sex-limited larval markings spinning white dumb-bell cocoons. After fixation, these breeds along with other newly evolved breeds were subjected for hybrid evaluation in the laboratory. Based on the hybrid studies, the hybrid SD7${\times}$SD12 was selected and evaluated for one year comprising three major sea- sons (6 trials) of tropics viz., Pre-monsoon (characterized by high temperature, low humidity and without any rain fall), Monsoon (characterized by moderate temperature, heavy rain fall with high humidity) and post-monsoon season (characterized by low temperature and low humidity with frequent rain fall) to know the fluctuations in the larval duration. The evaluation studies indicated that the hybrid is having shorter larval duration with productive merits. The hybrid SD7${\times}$SD12 recorded survival percent of 92.74, shell weight of 46.7 cg, shell ratio % of 24.0 and filament length of 1,200 meters with a shorter larval duration of 24 hrs; when compared to productive hybrid CSR2${\times}$CSR5(control). The breeding methodologies and hybrids usefulness for tropics were discussed.

• 한국건설관리학회논문집
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• 제4권4호
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• pp.155-163
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• 2003

최근 들어 주거공간의 기능만족과 효율성 확보를 위해 외기측에 면한 발코니 부위를 확장하는 사례가 늘어나고 있으며 특히, 최상층에 위치한 확장형 주거공간의 경우 외벽에 설치된 AL Curtain wall상부 외벽복합 Panel 이 완전 기밀하지 않음으로 인해 천정 상부측으로 낮은 외기온의 이동에 의한 실온과의 온도차에 의해 내부결로의 발생 가능성을 전혀 배제할 수는 없는 상황이다. 본 연구는 외기에 면한 초고층 아파트 최상층부의 발코니 천장내부에 있는 H-Beam(내화피복+단열재 구성)파 Parapet부위 내부결로 발생가능성에 대한 예측을 해 봄으로써 해당 공간거주자의 쾌적한 환경 만족 및 불안을 해소하는데 그 목적이 있다. 외주부를 구성하고 있는 Curtain wall Stone panel 또는 슬래브 바닥하부 등의 열적 취약공간에 대해 2차원 정상상태(온도평형) 열전도해석 Program을 이용, 온도예측과 온도분포해석을 통해 해당부위의 수증기압 분포에 따른 내부결로 예측을 실시하였다.

• Journal of Electrical Engineering and Technology
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• 제13권6호
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• pp.2392-2401
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• 2018

Creepage discharge faults in air on solid insulating material play a vital role in degradation and ageing of material which ultimately leads to breakdown of power equipment. And electric discharge decompose air in to its by-products such as Ozone and $NO_x$ gases. By analyzing air decomposition gases is a potential method for fault diagnostic in air. In this paper, experimental research has been conducted to study the effect of creepage discharge on rate of generation of air decomposition by-products using different insulating materials such as RTV, epoxy and fiberglass laminated sheet. Moreover XRF analysis has been done to analyze creepage discharge effect on these insulating materials. All experiments have been done in an open air test cell under constant temperature and pressure conditions. While analysis has been made for low and high humidity conditions. The results show that the overall concentration of air decomposition by-products under creepage discharge in low humidity is 4% higher than concentration measured in high humidity. Based on this study a mathematical relationship is also proposed for the rate of generation of air decomposition by-products under creepage discharge fault. This study leads to indirect way for diagnostic of creepage discharge propagation in air.

• 펄프종이기술
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• 제38권1호통권113호
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• pp.62-69
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• 2006

This study was carried out to measure and analyze the storage condition, distribution route, and packaging method of four selected agricultural products(small tomato, cabbage, peach, and carrot) in the cold chain system. It was shown that dew-forming phenomenon by fruits and vegetables deteriorates the agricultural product quality and physical properties of corrugated fiberboard box during the cold chain system. The compressive strength deterioration in corrugated fiberboard boxes was much greater for single wall(SW) corrugated fiberboard containers than for double wall(DW) in low temperature-high humidity condition. To reduce the deterioration of box and dew-forming phenomenon, water-repellency treatment should be over $R_6$. However, water-resistant treatment of corrugated fiberboard containers would be effective under high relative humidity conditions more than 75% RH. It was suggested that functional corrugated fiberboard box packaging would be an optimum method to reduce the deterioration of agricultural products quality by. It was also achieved controlling the relative humidity and temperature during the storage and physical distribution process.

• 한국인터넷방송통신학회논문지
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• 제16권5호
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• pp.185-190
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• 2016

국내 발전소에서 운전 중인 XLPE 케이블(또는 CV케이블)은 많은 경우 포설된 지 40년에 이르고 있다. 설치 후 운전 상태에 있는 대부분의 CV 케이블은 6~8년의 기간이 경과하면 열화가 발생하기 시작하고, 근래에 포설한 케이블이라 할지라도 사고가 발생할 수가 있으며, 사고 발생으로 인하여 막대한 손실을 초래하게 된다. 사고를 미연에 방지하기 위하여 케이블의 동작상태를 정기적으로 감시 확인하여야 한다. 우리는 케이블의 사고를 체계적으로 감시 및 예방하기 위한 목적으로 측정 시스템을 개발하였다. 이 장비는 수 년 동안 충남 태안에 소재한 한국서부발전주식회사(Korean Western Power Co. Ltd.)에서 케이블의 동작 상태를 감시하고 있다. 이 논문에서 시스템의 기능 및 동작 원리를 소개하고, 터빈 발전기 부하용 XLPE 고압케이블의 절연층 절연상태와 습도의 상간관계를 제시한다.

• 한국식품저장유통학회지
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• 제8권3호
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• pp.246-251
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• 2001

'창방조생 ' 과 '미백' 복숭아의 저장기간중 중량감모율은 상온무포장에서 4일후 각각 6.8%, 4.9% 이었으나 저온 (0~2$^{\circ}C$), 고습(95$\pm$3%) 조건에서 PE 무천공필름 포장저장구는 25일째 모두 1% 이내였다. 복숭아 저장중 경도변화는 상온에 비해 저온저장에서는 모두 큰 차이가 없었다. 두 품종 모두 저장기간중의 유기산과 가용성 고형분은 큰 차이를 나타내지 않았다. '칭방조생'과 '미백' 의 fructose, glucose 함량은 두 품종 모두 지장전보다 약간씩 증가였으나 Sucruse 함량은 25일 이후 감소하는 경향이었다. 복숭아는 30$\mu\textrm{m}$ LDPE fim 또는 25$\mu\textrm{m}$ SM60 film으로 포장하여 저온(0~2$^{\circ}C$), 고습(95$\pm$3%) 조건에서 저장할 경우 '창방조생'은 20일, '미백'은 25일까지 저장 가능하였다.