• Title/Summary/Keyword: round wood

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Predicting Influence of Changes in Indoor Air Temperature and Humidity of Wooden Cultural Heritages by Door Opening on Their Conservation Environment (개방에 따른 실내 온습도 변화가 목조문화재 보존환경에 미치는 영향 예측)

  • Kim, Min-Ji;Shin, Hyun-Kyeong;Choi, Yong-Seok;Kim, Gwang-Chul;Kim, Gyu-Hyeok
    • Journal of the Korean Wood Science and Technology
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    • v.43 no.6
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    • pp.798-803
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    • 2015
  • This study was conducted to predict the effect of door opening in wooden cultural heritages (WCHs) on their conservation environment. For this prediction, measured relative humidity (RH) and surface wood moisture content (MC) of inner part of wood columns in open wooden building and neighboring closed wooden building were compared with minimum RH, including the duration of minimum RH, and MC required for spore germination and resultant growth of wood-degrading fungi reported in some literatures. Moisture conditions, namely RH of inside wooden building and MC of wood was unsuitable for decay and sap-stain fungi all the year round; however, moisture conditions during summer season was suitable for spore germination and resultant growth of surface mold fungi, regardless of door opening. When compared, the duration of minimum (75%) or higher RH and the number of wood columns with MC level greater than the minimum MC (15%) during summer season, the surface mold related to the conservation environment of inside wooden building was somewhat better in open building than in closed building. Rather, doors should be opened in closed building for reducing indoor RH as a necessary measure during summer season when outdoor RH is high.

Strength Properties of Wooden Model Erosion Control Dams Using Domestic Pinus rigida Miller I (국내산 리기다소나무를 이용한 목재 모형 사방댐의 강도 성능 평가 I)

  • Kim, Sang-Woo;Park, Jun-Chul;Lee, Dong-Heub;Son, Dong-Won;Hong, Soon-Il
    • Journal of the Korean Wood Science and Technology
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    • v.36 no.6
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    • pp.77-87
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    • 2008
  • Wooden model erosion control dam was made with pitch pine, of which the strength properties was evaluated. Wooden model erosion control dam was made with diameter 90 mm of pitch pine round posts treated with CUAZ-2 (Copper Azole), changing joint in three different types. In each type, erosion control dam was made in nine floor (cross-bar of five floors and vertical-bar of four floors), of which the hight was 790 mm. And then strength properties were investigated through horizontal loading test and impact strength test, and the deformation of structure through image processing (AICON 3D DPA-PRO system). In horizontal loading test of wooden model erosion control dam using round post of diameter 90 mm, whether there was stone or not did not affect strength much when using self drill screw, but strength was decreased by 23%. In monolithic type of erosion control dam using screw bar, strength was increased by 1.5 times and deformation was decreased when filling with stone. When reinforcing with screw bar that ring is connected to self drill screw, strength was increased by 4.8 times. In impact strength test of wooden model erosion control dam made with round post of diameter 90 mm, the erosion control dam connected with self drilling screw not filling with stone was totally destroyed by the 1st impact, and the erosion control dam using screw bar was ruptured at cross-bar at which 779 kgf of impact was loaded in the 1st impact. In the 2nd impact, the base parts were ruptured, and reaction force was decreased to 545 kgf. In the 3rd impact, whole base parts were destroyed, and reaction force was decreased to 263 kgf.

Pressure Treatment of Japanese Red Pine, Japanese Larch, and Ezo Spruce Round Posts with CCA (소나무, 낙엽송, 북양가문비나무 원주가공재의 CCA 가압처리)

  • Kim, Gyu-Hyeok;Kim, Jae-Jin;Kim, Hyung-Jun
    • Journal of the Korean Wood Science and Technology
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    • v.28 no.1
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    • pp.42-47
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    • 2000
  • This study was designed to investigate the effect of treatment variables on CCA treatment of Japanese red pine (Pinus densiflora), Japanese larch (Larix leptolepis), and ezo spruce (Picea jezoensis) round posts. Variables included were duration of initial vacuum (30, 45, or 60 minutes) and maximum pressure applied (8.5, 10.5, or 14.0 kg/$cm^2$), and maximum pressure was maintained until refusal point was reached. Regardless of wood species, extending the duration of initial vacuum more than 30 minutes did not affect treatability. Increasing pressure did not affect preservative penetration; however, preservative retention was affected by pressure levels, particularly at higher level (14.0 kg/$cm^2$). Preservative penetration depth of Japanese red pine met a minimum requirement specified by Notification of Korean Forestry Administration (No. 1999-8) for hazard class H5 of CCA-treated wood. Penetration of preservative in both Japanese larch and ezo spruce was not deep because of shallow sapwood thickness of these species, so pretreatment such as incising should be considered if these species are treated with preservatives. Although retention in Japanese red pine was not significantly increased even with 14.0 kg/$cm^2$, that of refractory Japanese larch and ezo spruce was significantly increased with the application of 14.0 kg/$cm^2$. Effect of treatment variables on refusal time was unclear; however, it is cleared that the refusal time was shortened with the increase in sapwood thickness.

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A Structural Characteristics of Hwatong-Connections in Traditional Mindori Type of Wood Structures (전통 민도리식 목구조 화통맞춤의 구조적 특성)

  • Yu, Hye-Ran;Kwon, Ki-Hyuk
    • Journal of architectural history
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    • v.21 no.3
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    • pp.7-28
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    • 2012
  • This study is intended to Mindori structure which is general private houses' structural type among traditional types and is a basic study to confirm structural characteristics of Hwatong connection which is general connection type of column-beam-cross beam. It is aimed to analyze how main member, column, such as size, figure, thickness of Sungetuk and Dugeup affect on structure. Following conclusions are drawn. 1. According to connection conditions, models with big coefficient of friction show stable hysteretic behavior until the angle rotation of member reaches 1/60 and models with small coefficient of friction show dramatical increase in load after the angle rotation of member reaches 1/24. After the angle rotation of member reaches 1/30, separation distance of members is identified physically and cracks are not observed. 2. Specimens with big coefficient of friction show similar inner force regardless of column size(except column size 150mm) and models with small coefficient of friction show increasing inner force as the column size increases. Specimens with same sectional area have similar inner force even though the column figures are different. The thickness of Sungetuk and Dugeup doesn't affect inner force greatly, however, when the thickness of Sungetuk is thin, it could lead to failure of structure as it breaks. 3. The bigger the size of column and the coefficient of friction are, the smaller Bending stiffness depreciation ratio is. 4. Energy Dissipation Efficiency differs from the coefficient of friction. When the coefficient of friction is big, square column shows bigger than round one and it is bigger when the thickness of Sungetuk and Dugeup is thicker. When the coefficient of friction is small, round column shows bigger than square one.

A Study on the Korean Pillows (우리나라 베개(침)에 관한 소고 -유물과 문헌을 통하여-)

  • 남윤자
    • Journal of the Korean Home Economics Association
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    • v.27 no.1
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    • pp.19-27
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    • 1989
  • The purpose of this study is to find at the basic data for the appropriate conditions of the pillows for the Koreans. In this study, the origins, materials, the forms and the sizes of Korean pillows have been investigated by means of existing remains and the existing documentary records. The results are as follows : 1) We can infer that ordinary pillows have already been used in a period of the three kingdoms, because the pillows for the dead bodies been unearthed from the tombs of this period. 2) Round pillows which are used nowadays to rest our heads have also been utilized as early as in Koryo Dynasty or even in the previous period. It is because the pillows described in Koryo dakeyung are similar to the present round ones. Most of the existing Koryo pillows have been made fo ceramics. Their average length is 20.0$\pm$5.4cm, the average low height is 9.7$\pm$0.9cm, and their average high height is 11.8$\pm$1.2cm. 3) The material which has been used to make pillows in Choson Dynasty is various : textile, wood, rush, bamboo, ceramics, etc. Most of them have been made in a round form or in a form of lying square. The average low height of lying squares is 8.1$\pm$2.5cm. The average high height is 11.9$\pm$1.9cm, and the average lenght is 19.0$\pm$5.6cm. The average diameter of embroidered pads attached to both sides of round pillows or the average length of one side of regular squares is 12.5$\pm$2.3cm.

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Deterioration and Preservation Technique of Wooden Cultural Properties (Part 2) -Biodeterioration of Square Post to Support Wooden Printing Blocks Shelves, Janggeongpanjeon- (목조문화재 열화 및 보존기술에 관한 연구(제2보) -장경각 구조부재중 실내 판가 기둥의 생물적 열화 특성-)

  • Kim, Yeong-Suk;Han, Sang-Mi
    • Journal of the Korean Wood Science and Technology
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    • v.35 no.1
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    • pp.64-72
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    • 2007
  • The biodeterioration behaviors of square post to support the wooden printing blocks Shelves in the Janggeongpanjeon were investigated according to the positions and parts of square post, and environmental conditions. It was found that a high differences of deterioration in the progressing levels of wood decay, according to the positions and parts of square post, and environmental conditions. The decay levels were very high and still progressing in the contacted areas with stone foundation which are about up to 50 cm above it. In the decay type, white rot fungi was mainly affected in the inside of building which mainly made of softwood. The decay in the square posts to support the wooden printing block shelves inside of building was worse in the rear side, compared to front side. The insects was not found in most of square posts excluding the post which was neighboring at the infected round column by insect.

Environmental Suitability for Conservation and the Risk Period for Fungal Damage of Wooden Cultural Heritages in Korea

  • Ik-Gyun IM;Gyu-Seong HAN
    • Journal of the Korean Wood Science and Technology
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    • v.51 no.4
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    • pp.295-308
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    • 2023
  • This study applied a real-time IoT (Internet of Things) environmental monitoring system to wooden cultural heritages (WCHs) located in suburbs and forests in Korea. It automated the graphs of seasonal Temperature (T) and relative humidity (RH) changes inside the heritage structures and seasonal Performance Index (PI) values. While utilizing line graphs of the existing T and RH change trends and a bar graph expressing the PI values, this study examined the current status of the conservation environment inside the WCHs throughout the year and its diagnosis. Consequently, at higher latitudes, the organic cultural heritage repeatedly experienced large T fluctuations, and the risk of physical and chemical degradation of the materials was greater. However, the RH showed significant seasonal differences, even within the same latitude, indicating that the impact of latitude was not significant. Therefore, the staff in charge must manage RH by considering the surrounding environmental conditions and adjusting the internal environment of the structures. The PI values for the year-round T and RH inside the heritages were confirmed to only be a maximum of approximately 60% of the environmental suitability for conservation throughout the year, depending on the season. The relationship between the germination and growth potential period of xerophilic fungi and the monthly internal temperature and humidity in five heritages located at different latitudes was analyzed. As a result, we could thus determine that four particular months of the year (June-September) represent the periods with the highest risk of damage from xerophilic fungi in the country, regardless of latitude.

Chemical Composition of Rice Hull and Morphological Properties of Rice Hull Fibers (왕겨의 화학적 조성 및 왕겨섬유의 형태적 특성)

  • Sung, Yong-Joo;Shin, Soo-Jeong;Oh, Min-Taek
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.41 no.3
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    • pp.22-28
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    • 2009
  • The rice hull could be the one of the most abundant agricultural waste in Korea. Since the efficient utilization of agricultural waste or byproducts of food industry would be critical for the sustainable growth, this study conducted the investigation of the chemical composition and the morphological properties of rice hull and rice hull fiber. It was found that there was big difference between the outer surface and the inner surface in the chemical composition and the morphological properties. Expecially, the outer surface showed the rugged patterns in which most of silica of rice hull existed. Little or no silica was found in the inner surface and rice hull fiber. The average fiber length of rice hull fiber was 0.45mm which was shorter than that of hardwood fiber. Rice hull fiber showed a round long shape which is typical shape of non-wood fibers

A Study on the Oral Health of Smokers (흡연이 구강보건에 미치는 영향에 관한 연구)

  • 이승우
    • Journal of Oral Medicine and Pain
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    • v.3 no.1
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    • pp.3-10
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    • 1977
  • Few changes were found in the mouths of 52 smokers were examined as a part of program to evaluate the oral health of Korean smokers. 52 smokers and 30 non-smokers were performed careful oral examination. In many of smokers, heavy, black deposits are found on the buccal and lingual surfaces of the teeth and leukoplakia were obsreved in 2 subjects and varied merely in the severity of the involvement. Cytologic studies were carried out on 60 oral smears from the hard palate, buccal mucosa, and gingiva. Smears were taken wit a wood spatula scraped over the mucosal surface. After fixation the slides were stained using the papanicolau cells without nuclei. The cornified cells were smaller than the noncornified cells and stained a deep brown or orange as compared with the blue or red of the large, round or polygonal cells in nonkeratinized regions of oral mucosa. Abnormal cell forms, suggestive of malignancy were not found in smears from the mucosa of smokers. Cells with large hyperchromatic nuclei and elongated, spindle-type cells with large nuclei were not observed.

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Immunoelectron Microscopic Localization of Prolactin in Rat Exolacrimal gland (흰쥐 눈물샘의 Prolactin 존재에 관한 면역전자현미경적 연구)

  • Park, Kyung-Ho;Wood, Richard L.
    • Applied Microscopy
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    • v.23 no.1
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    • pp.25-34
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    • 1993
  • Prolactin has been reported to be present in the tear film of humans and prolactin-like immunoreactivity has been detected by immunofluorescence in acinar cells of the lacrimal glands of humans and rats. The present study was aimed at clarifying the intracellular distribution of the prolactin-like immunoreactivity, using the electron microscope immunogold technique. The lacrimal gland acinar cells have two types of secretory granules: 1) Secretory granules containing flocculent materials irregularly shaped and are often coalesced. 2) Secretory granules are fairly round and contain homogenous materials of a moderate electron density. The density of the granular content varies even within a single cell. We found prolactin-like reactivity in secretory granules, some smaller cytosolic vesicles, Golgi cisternae and nuclei in acinar cells from intact glands of rat. Our present results are consistent with the conclusion that prolactin is present in lacrimal cells. The presence of prolactin reactivity in the nucleus suggests that prolactin may be a regulatory factor modulating gene expression.

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