• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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• pp.265-266
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• 2009

콘크리트의 내구성, 즉 염해, 증성화, 동해, 화학적 침식 등의 열화현상을 예측하기 위해서는 우선 콘크리트 내부의 온습도를 파악하는 것이 무엇보다도 중요하다. 본 연구에서는 열-수분 이동을 고려 한 복합 물리적 모델 구축 및 실측을 통하여 시간경과에 따른 콘크리트 내부의 온습도 변화를 추정하고자 하였다.

• 한국해양공학회지
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• 제10권4호
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• pp.38-50
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• 1996

Recently carbon fiber reinforced plastic (CFRP) has been used structural materials in corrosive environment such as for water, chemical tank and pipes. However, mechanical properties of such materials may be change when CFRP and exposed to corrosive environment for long periods of time. The degradation behavior of carbon fiber/epoxy resin composite material in distilled water is investigated using acoustic emission (AE) technique, Fracture toughness tests are performed on the compact tension specimens that are pilled by two types of $[O_2/9O_2]_{3s}$ and $[O/9O]_6s$. During the testes, AE test was carried out to monitor the damage of CFRP by moisture absorption. The data was treated by 2-parameter Weibull distribution and the fracture surface was observed by scanning electron microscope.

• 한국작물학회지
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• 제33권2호
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• pp.201-204
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• 1988

태풍 'Thelma'(87년 7월 15~16일)로 엽신 손상장해가 심했던 통일형품종(한강찰벼, 삼강벼, 가야벼, 남영벼)과 일본형품종(팔공벼, 동진벼, 섬진벼, 대창벼)을 대상으로 엽신고사정도와 이에 관련한 잎의 생리 생태적 특성을 조사하여 다음과 같은 결과를 얻었다. 1. 바람에 의한 엽신의 고사율은 일본형품종들이 3.1~4.4%인데 비하여 통일형품종은 5.1~8.0% 로서 품종군별 고사율의 차이가 현저하였다. 2. 엽신손상이 컸던 통일형품종들은 일본형품종들에 비하여 엽신이 다소 짧으면서 광엽이었고 엽신중의 규화세포수가 현저히 많았으며 기공개도가 커서 수분손실율이 높았다. 3. 엽신의 손상정도는 엽신의 기공개도(r=0.8460$^{**}$ ), 수분손실율(r=0.8343$^{**}$ ) 및 규화세포수(r=0.7546$^{*}$ )와 각각 유의한 정의 상관관계가 인정되었다.관계가 인정되었다.

• Geomechanics and Engineering
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• 제23권3호
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• pp.227-244
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• 2020

Earthen structures have an excellent bioclimatic performance, but they are vulnerable against earthquakes. In order to investigate the edification process and costs, a full-scale rammed soil house was constructed in 2004. In 2016-2019, it was studied its seismic damage, durability and degradation process. During 2004-2016, the house presented a relatively good seismic performance (M_w=5.6-6.4). The damaged cover contributed in the fast deterioration of walls. In 2018 it was observed a partial collapse of one wall due to recent seismicity (M_w=5.6-6.1). The 15-year-old samples presented a reduced compressive strength (0.040 MPa) and a minimum moisture (1.38%). It is estimated that the existing house has approximately a remaining 20% of compressive strength with a degradation of about 5.4% (0.0109 MPa) per year (considering a time frame of 15 years) if compared to the new soil samples (0.2028 MPa, 3.52% of moisture). This correlation between moisture and compressive strength degradation was compared with the study of new soil samples at the same construction site and compared against the extracted samples from the 15-year-old house. At 7-14-days, the specimens presented a similar compressive strength as the degraded ones, but different moisture. Conversely, the 60-days specimens shown almost five times more strength as the existing samples for a similar moisture. It was observed in new rammed soil that the lower the water content, the higher the compressive/shear strength.

• 한국작물학회지
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• 제14권
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• pp.147-157
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• 1973

I. 보리 발아시 과습조건이 될 때 그 발아에 미치는 영향을 알고져 건토(LiC) 100g당 30cc, 40cc, 50cc, 60cc의 비율로 물을 가하여 수분함량을 각각 다르게 한 조건을 만들어 Check에 대비하여 Machete(Butachlor), TOK(Nitrofen)을 각각 150g, ai/10a 비율로 처리하였던바 그 결과를 요약하면 다음과 같다. 1. 보리 발아시 수분함량이 포장용수량 이상의 과습이 유지될 때는 무처리구에 있어서도 발아율이 급감하거나 발아되지 아니하며 일단 발아된 후에도 근신장 및 생육이 제대로 되지 못하였다. 2. Machete, TOK 등 약제처리구에 있어서도 1)과 경향은 같으나 무처리구 보다는 그 해가 더욱 증대되였다. II. 토성이 다른 4종류의 토양을 대상으로 하여 Machete (제형별 180 g ai/10a), TOK (약량별 150g, 200g ia/10a), saturn(150g ai/10a), HE314, (250g ai/10a)의 4약제를 사용하여 1cm 복토심하에서 완주 봄보리에 대한 약해차이실험을 실시하였든바 그 결과를 요약하면 다음과 같다. 1. Machete 제형별(180g ai/10a 수준) 약해는 토양의 종류에 따라 심한 차이가 있었으며 식양토에서는 제형에 관계없이 거의 안전하나 사질 식양토<화산회양토<사양토 순위로 약해가 증대되었다. 유제의 약해의 입제의 약해보다 더욱 심하였다. 2. TOK 수화제 150g-200g ai/10a Machete와 거의 동일의 경향이며 약량이 높을 때 약해는 더욱 심하였다. 3. Saturn 150g ai/10a 토성에 따른 약해차이가 있기는 하나 그 차가 심하지는 아니하였다. 4. HE314. 250g ai/10a 250g 시용수준에서는 토성에 따른 약해차가 거의 없었다. III. 2종류의 토양을 대상으로 9개약제(TOK. MO. HE314, Machete, Saturn, Simetryne, Simazine, Gesaran Lorox)을 사용하여 복토심별(4단계)로 약해발생차이를 구명하였던바 그 결과를 요약하면 다음과 같다. 1. 경식ㅌ조건 : 1) Check에 있어서 복토심별 생육상황은 1cm>1.5cm>0.5cm>0cm의 순위였으며 0-0.5cm 복토구에 있어서는 보리 생육이 매우 불량하였다. 2) 약제처리구에 있어서도 0-0.5cm구에 있어서는 심한 해를 나타내고 있으며 1cm 이상의 복토가 유지될 때 보리에 비교적 안전한 약제는 Saturn, Machete, MO, TOK의 100-150g ai/10a, HE314 375-205g ai/10a구 등이었다. 3) 1.5 cm 복토에 있어서도 징해를 나타낸 약제는 Simazine, Lorox, Simetryne 등이었다. 2. 사질토조건 : 1) Cheick에 있어서 생육상황은 1.5cm>0.5cm>0.5cm>3cm>5cm의 순위이었다. 2) 약제처리구에 있어 MO는 1.5 cm 구에서 안전하였고 TOK의 약해는 1.5cm인때 가장 가벼운 편이다. 3) 3cm이상 복토가 될 때 비교적 안전한 약제는 Machete, Saturn 100g ai/10a, HE314 250g ai/10a 이었다. 4) 복토심에 구애없이 불안전한 약제는 Simazine, Lorox, Simetryne Gesaran 등이었다.

• 수산해양기술연구
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• 제32권4호
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• pp.402-410
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• 1996

Recently carbon fiber reinforced plastic(CFRP) has been used structural materials in corrosive environment such as for water, chemical tank and chemical pipes. However, mechanical properties of such materials may change when CFRP are exposed to corrosive environment for long periods of time. Therefore, it is important to understand the effect of moisture absorption on mechanical properties of the CFRP. In this study, degradation behavior of immersed carbon fiber/epoxy resin composite material was investigated using acoustic emission(AE) technique. Fracture toughness test are performed on the compact tension(CT) test specimens that are pilled by two types of laminates $[0^{\circ}_2$/$90^{\circ}_2]_3s$ and $[0^{\circ}_2$/$90^{\circ}_2]_6s$During the fracture toughness test, AE test was carried out to monitor the damage of CFRP by moisture absorption. In spite of the change of moisture absorption rate, the fracture toughness of CFRP was not change. As immersion time increased, AE event count numbers decreased in low amplitude range of AE for amplitude distribution histogram. The event in low amplitude range was known to be generated by debonding of matrix-fiber interface. Therefore, decrease of AE event count numbers in low amplitude range represents that debonding of matrix-fiber interface which was probably generated by moisture absorption.

• 한국연초학회지
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• 제11권2호
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• pp.241-246
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• 1989

Mold development on leaf tobacco(Flue-cured, var. NC 82) during the storage was examined according to the initial moisture content(MC) of the tobacco. The initial moisture content of the leaf tobacco was controlled as 12,14,16% after redrying. Those were packed in cardboard boxes and stored in a warehouse. Samples were taken monthly from June of 1988 through August of 1989 and were evaluated for mold development (colony count) and MC. The moisture content change in the leaf tobacco of 12, 14 and 16% initial MC was in the range of 11.1-13.3, 12.8-15.3 and 14.9-16.7% and the mean number of colonies from them were 1.4$\times$102, 1.0$\times$102, and 4.0$\times$102 colonies per gram of tobacco, respectively, however mold-damaged leaf tobacco other than the treatments was occasionally observed to have the colony number as high as 2.3$\times$105 colonies per gram of tobacco. In the meantime, the leaf tobacco was stored at 6 relative humidity levels at $25^{\circ}C$ in laboratory test. Leaf tobacco of 15.0-16.4% MC was maintained without the mold-damage after 80 days of storage whereas those of 19.9, 21.3, 25.5 and 27.1% MC became moldy after 50, 15, 11 and 6 days of storage, respectively.

• 한국조리학회지
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• 제5권2호
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• pp.165-190
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• 1999

There are no reliable data about the effect on the baking industry in Korea yet. The damage caused by the product's aging is so much in the confectionary and baking industries. Therefore, the aging of bread is an economical problem which determines its commercial lifespan. In order to solve out this aging problem, this article dealt with the factors which give rise to the effect of starch on the aging and its inhibitory methods. 1. Control of the moisture content : Because the aging of starch occurs at 30~60% of moisture most frequently, controlling the moisture content above or below the above percentage can help restrain the aging to a certain degree. 2. Addition of sugars : The sugars become hydrated through hydrogenation with the moisture in the food. Thus, the sugars suppress the phenomenon of crumbling inside the food acting as a kind of dehydrator. 3. Use of an emulsifying agent : The emulsifying agent increases the stability of starch colloid liquid and suppresses the precipitation of starch molecules and the formation of crystallized range to prevent aging. 4. Method by freezing : The aging of starch does hardly occur reaching -2$0^{\circ}C$~-3$0^{\circ}C$ below zero. 5. Maintenance of warm condition : The freshness of bread is maintained at the 80% of humidity at 5$0^{\circ}C$.

• International Journal of Computer Science & Network Security
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• 제22권9호
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• pp.403-413
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• 2022

Classification and analysis are improved factors for the realtime automation system. In the field of agriculture, the cultivation of different paddy crop depends on the atmosphere and the soil nature. We need to analyze the moisture level in the area to predict the type of paddy that can be cultivated. For this process, Ensemble Modulation Pattern system and Block Probability Neural Network based classification models are used to analyze the moisture and temperature of land area. The dataset consists of the collections of moisture and temperature at various data samples for a land. The Ensemble Modulation Pattern based feature analysis method, the extract of the moisture and temperature in various day patterns are analyzed and framed as the pattern for given dataset. Then from that, an improved neural network architecture based on the block probability analysis are used to classify the data pattern to predict the class of paddy crop according to the features of dataset. From that classification result, the measurement of data represents the type of paddy according to the weather condition and other features. This type of classification model assists where to plant the crop and also prevents the damage to crop due to the excess of water or excess of temperature. The result analysis presents the comparison result of proposed work with the other state-of-art methods of data classification.

• 건축역사연구
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• 제32권2호
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• pp.37-48
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• 2023

A literature study was conducted on the management of the pavilion of the royal tomb in the late Joseon Dynasty, focusing on "Gakneung Suri Deungnok(Records relating to the repair of royal tombs)". This study analyzed the royal tomb management system, organized the types of damage identified in the building, and examined how the damage status was recorded by type. In the above, the records related to the 1675~1713 repair of three JeongJaGak(Geonwonneung, Sungneung, and Mokneung), which are registered as state-designated cultural properties, are summarized in three aspects: management system, damage status, and expression words. The results of the study are as follows. First, the royal tomb pavilion was regularly inspected by Observator(觀察使) in spring and autumn, and Surunggwan(守陵官) every 5th, and Servant(守僕) regularly inspected every day and night, and also inspected and reported emergency cases of natural disasters or unexpected damage. Second, the damage status of each building was continuously observed and reported for the continuous maintenance of the buildings in the royal tomb. A total of 75 records of damage to the three royal tombs' pavilion were found to have been most frequently inspected, including 19 cases (25.3%), 14 cases (18.7%), 23 cases (30.7%) of the roof, and 19 cases (25.3%) of the roof. Third, the expression of the damage status is confirmed in various ways, such as separation, separation, burst, damage, excitation, moisture, leakage, and exfoliation. Among them, the main damage records were confirmed due to the separation of the base from the peeling, the furniture, cracks, leaks, leaks in the roof, and the collapse of the roof was able to check the damage records.