• KOREAN JOURNAL OF CROP SCIENCE
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• v.3
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• pp.99-107
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• 1965

Thirteen varieties of hemp, Cannabinus sativa L., consisting of four Italian, one Japanese and eight local varieties were used in the study on the fiber content and a satisfactory selection for the higher-fiber-yielding plants. In addition, the relationship among fiber contents at the ball setting stage, and at the maturity stage, primary fiber content, and total fiber content were determined. The results of the study are summarized as follow: 1. Fiber weight of the matured male plant expressed as percentage of the fiber weight to dried stems varied from 12.09 to 26.71 percent for the Italian varieties, 14.25% for the Japanese variety and ranged from 6.59 to 16.79 for the local varieties. It was shown that on the average, Italian varieties contained more fiber compared with the other varieties. 2. On the same basis, the average percent age of fiber for Italian male plants was 20.77 while it was 20.96 for female plants. For the Japanese variety, similar figures were 14.24 for male plants and 15.43 for female plants. By comparison, the average percent fiber for the male plants of Korean varieties was only 10.34 but averaged 16.79 for female plants. In this experiment, female plants contained a greater percentage of fiber than male plants. 3. Statistically significant correlations were obtained between fiber content at the ball setting stage and fiber content of the mature plant. The correlation coefficient was r=0.942＊＊, while the regression equation was Y=0.28+1.03X. These data indicate that plant. selection by early testing at the ball setting stage is an effective method for the improvement of fiber content. 4. The correlation between primary fiber content and total fiber content was r=0.913＊＊, with a regression equation of Y=12.01+1.20X. It should thus be possible to obtain plants of higher total fiber content at maturity by the selection of plants which have a higher content of primary fiber at the ball setting stage. 5. From a study of the transverse sections from the hemp plant it was shown that Italian varieties have wide bands of primary and secondary fibers with narrow areas of woody material, while both Korean local varieties and Japanese varieties have narrow bands of primary and secondary fiber and wide areas of woody material. For hemp improvement, it is certain that a variety which has a narrow area of woody substances and wide area of fiber in its stem should be selected.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.412-415
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• 2004

This study was performed to verify the behaviors of fiber Bragg grating (FBG) sensors attached to the containment structure in the nuclear power plant as a part of structural integrity test which demonstrates that the structural response of the non-prototype primary containment structure is within predicted limits plus tolerances when pressurized to $115\%$ of containment design pressure, and that the containment does not sustain any structural damage.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.9
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• pp.1366-1375
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• 2008

This studies were carried out in order to develope environmentally-friendly fiber materials and substitute resources of Paper mulberry. Various plant fibers such as New Zealand flax, Indian mallow, Kuzu vine and Yucca were used as raw materials of hand-made papers. We rotted these 4 kinds of plant fibers and removed non-cellulose. After rotting, the pulping rate(%) and the length of fibers in pulps were measured. The physical characteristics of papers made of various plants fiber were investigated and the probabilities of practical use were considered. The results were as follow: The non-cellulose contents of plant fibers were $30{\sim}40%$ and those contents must be lower down to 8% to be able to manufacture the hand made papers. The lignin in pulps were removed almost and the hemicellulose were partially removed to reach up to appropriate level of the pulp rates and fiber lengths. The more hemicellulose removed, the finer fiber thickness were and rapidly the lower Hanji tensile strength were. But the tear strength of these plants of hand-made papers do not decreased so much as tensile strength. So the property of 4 types of plant fibers might be of great advantages to make hand-made papers. Both tensile and tear strengths of Hanji of New Zealand flax, Indian mallow, Kuzu vine and Yucca were higher than Paper mulberry hand-made paper. When 30% of mulberry paper were mixed, the mixing effect showed maximum. Because of the functions of all plant fiber hand-made papers showed better than those of Paper mulberry hand-made paper, 4 types of plant fibers could be substitute Paper mulberry.

• Journal of Environmental Science International
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• v.20 no.10
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• pp.1233-1241
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• 2011

The main objective of this experimental investigation was $CH_4$ recovery from biogas generated in municipal and wastewater treatment plant. The polysulfone hollow fiber membrane was prepared in order to investigate the permeation properties of $CH_4$ and $CO_2$. Permeability of $CO_2$ in Polysulfone membrane was 11-fold higher than of $CH_4$ gas. A membrane pilot plant for upgrading biogas was constructed and operated at a municipal wastewater treatment plant. The raw biogas contained 66 ~ 68 Vol % $CH_4$, the balance being mainly $CO_2$. The effect of the operating pressure of feed and permeate side and feed flowrate on $CH_4$ recovery concentration and efficiency were investigated with double stage membrane pilot plant. The $CH_4$ concentration in the retentate stream was raised in these tests to 93 Vol % $CH_4$.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.635-638
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• 2007

In this paper, we described the fundamental concepts of proposed structural health monitoring system for Uldolmok Tidal Current Power Plant focusing on the use of smart sensors including fiber bragg grating sensors and macro fiber composite sensors. The structural health monitoring system can play an important role to maintain the structural safety for offshore structures like as bridges and high-rise buildings. In the case of tidal current power plant, the monitoring system is much more important since the structures are usually constructed at the site with severer environmental loadings such as high current speed.

• Nutritional Sciences
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• v.7 no.2
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• pp.113-120
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• 2004

This study was conducted to investigate variables related to dietary fiber intake among sixth grade children in an elementary school in Daejon city. One hundred and forty-seven children completed a questionnaire for determining their socioeconomic background and their food habits. Anthropometric measurements were taken, and a 24-hour diet recall method was used to collect three-day food intakes. The socioeconomic status of the children's families belonged to the upper middle class; 53.0% of their fathers and 25.8% of their mothers had completed college or higher degrees. 27.9% of the mothers had jobs, including part-time jobs. Approximately 30% of the children skipped breakfast, 66.4% of the children preferred animal foods to plant foods, and 52.4% of the children preferred green vegetables to yellow or pale vegetables. Grilled meat dishes, such as Grilled beef rib with seasoning, Bulgogi, grilled pork belly and beef steaks, were the most popular types of food eaten outside home by the children. Daily dietary fiber intake was 14.5 g in boys and 14.5 g in girls, and these intakes are low compared to the standard guidelines. The average intakes of energy and protein of the children were 84.5% and 114.0% of the Korean Recommended Dietary Allowances (RDAs), respectively. Besides energy, riboflavin, iron and calcium intakes were below the RDAs, and especially calcium intake was only 50% of the RDAs. On the other hand, thiamin, niacin, ascorbic acid, protein and phosphorus intakes exceeded the Korean RDAs. Family income or the children's body mass index (BMI) was not directly related to dietary fiber intakes. However, higher dietary fiber intakes tended to be related to higher intakes of green vegetables and fruits. Children with higher dietary fiber intake tended to prefer plant foods to animal foods. Energy and most nutrients, except heme iron and retinol, showed positive relationships with dietary fiber intake. Especially potassium and plant origin protein and calcium were highly correlated with dietary fiber intakes(r＞0.6). From these results, it is concluded that dietary fiber intakes of these sixth grade elementary school children were less than the standard reference and it is anticipated to decrease further in the future with increased incomes. Therefore, increased intakes of dietary fiber by elementary school children should be promoted through nutrition education, together with the development of cooking methods and recipes utilizing green vegetables and fruits.

• Fibers and Polymers
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• v.5 no.3
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• pp.171-176
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• 2004

Fiber fineness characteristics are important for yarn production and quality. In this paper, degummed bast fibers such as hemp, flax and ramie have been examined with the Optical Fiber Diameter Analyzer (OFDA100 and OFDA2000) systems for fiber fineness, in comparison with the conventional image analysis and the Wira airflow tester. The correlation between the results from these measurements was analysed. The results indicate that there is a significant linear co-relation between the fiber fineness measurement results obtained from those different systems. In addition, the mean fiber width and its coefficient of variation obtained from the OFDA100 system are smaller than those obtained from the OFDA2000 system, due to the difference in sample preparation methods. The OFDA2000 system can also measure the fiber fineness profile along the bast fiber plants, which can be useful for plant breeding.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.5
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• pp.1730-1734
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• 2010

Generally, a pH value of secondary water in a nuclear power plant should be estimated after sampling and cooling down. In this process, the measurement of temperature is very important because a pH value is varied according to the temperature of secondary water. In this study, a noncontact fiber-optic temperature sensor using a silver halide optical fiber is fabricated to measure the temperature of cooled secondary water. And we have measured an infrared radiation, which is transferred by a silver halide optical fiber from a heat source, using a thermopile sensor. The relationships between the temperature of a heat source and the output voltage of the fiber-optic temperature sensor according to the change of distance and angle are determined. The measurable temperature range of the fiber-optic temperature sensor is from 25 to $60^{\circ}C$. Based on the results of this study, a noncontact temperature sensor using a silver halide optical fiber can be developed for the temperature measurement of the pH sample in the secondary water system.

• Korean Journal of Plant Taxonomy
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• v.34 no.4
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• pp.321-333
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• 2004

We researched fruit wall anatomical characters about the seven taxa of Krigia and the nearest one relative, Nothocalais cuspidata by making use of the fruit wall anatomy, and inferred systematical similarity. Among these characters, all species of the genus Krigia has identical characters in the shape of fruit and the number of rib, but showed specific differences in the shape of costa, the numbers of libriform fiber cell layers and fiber-sclereid cell layers in mesocarp, and development degree in these characters. Krigia biflora, K. cespitosa, K. occidentalis and K. wrightii have well developed libriform fiber cell, but K. dandelion, K. montana and K. virginica have undeveloped libriform fiber cell, and mostly consist of fiber-sclereid cell layers. According to the fruit wall anatomical characters, K. biflora which belonged to sect. Krigia in the previous classification system is more similar to sect. Cymbia than sect. Krigia.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.40 no.4
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• pp.1-9
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• 2008

The utilization of non-woody fibers with the fast growing annual plants has occurred in the paper industry to replace wood and preserve environment of the earth. The non-woody fibers generally used for papermaking are paper mulberry, gampi, manila hemp, rice straw, bamboo, and coton linter etc.. Recently Kenaf has been spot-lighted for the same application. Kenaf is an annual plant of Hibiscus species of Malvaceae family. Kenaf, a rapid growing and high harvesting non-woody fiber plant, was identified as one of the promising fiber sources for the production of paper pulp. This study was carried out to investigate the pulping characteristics of Kenaf bast fiber for Hanji (traditional Korean paper) manufacturing by different pulping methods, such as alkali, alkali-peroxide and sulfomethylated pulpings. It was possible to make superior grade of Hanji. Especially sulfomethylated pulping was resulted in superior pulp in terms of higher yields and qualities in comparison to those of the other pulping methods. Hanji from sulfomethylated pulp was shown the highest brightness of over 60% and higher sheet strength. In addition, the morphological features of pulp fibers (pulp compositions) affect to the sheet properties. Therefore the effect of fiber distribution index(FDI) which was calculated from the data of Confocal laser scanning microscopy(CLSM) on the sheet properties of Kenaf Hanji was also discussed.