• Journal of Korean Society for Atmospheric Environment
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• v.13 no.4
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• pp.285-296
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• 1997

The suspended particulate matters had been collected on quartz fiber fiters by a cascade impactor having 9 size stages for 4 years (Sep. 1991 to Dec. 1995) in Kyung Hee University-Suwon Campus. Membrane filters were used to collected the particulate matters on each stage. The weight concentration on each stage was obtained by a microbalance and further chemical element levels were determined by an x-ray fluorescence system. Based on these chemical information, our study focused on applying the target transformation factor analysis (TTFA), a receptor model, to identify aerosol sources and to apportion quantitatively their mass contribution. There are total of 63 ambient data sets. Each data set consists of the 8 size-ranged subdata sets characterized by 16 elemental variables. By the results, four to five sources were extracted from each size range and some sources reappeared in other size ranges. Then total of 8 source profiles were statistically generated from all the ranges, such as oil burning source, soil source, field burning source, gasoline related source, coal burning source, marine source, glass related source, and unknown sources. Apportioning aerosol mass to each source was intensively examined by investigating emission inventories near the study area. The results showed that soil particle source was the most significant contributor. However, coal and oil burning sources were the major anthropogenic ones. The study finally proposed some air quality control strategies to achieve the clean air quality in Suwon area.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.7
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• pp.1063-1069
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• 1999

Wheat straw samples (3-4 cm) were sprayed with solutions of urea (U) alone or with a dry addition of garden soil (GS), midden soil (MS), soya bean meal (SM) or jack bean meal (JM) as crude urease sources and with a pure urease (UR) enzyme. Each of the urease sources was included at two levels: 30 and 60 g/kg except pure urease, which was added at a level of 2.5 & 5.0 g/kg treated straw dry matter. Untreated straw without urease source was used as a control. After treatment, samples were sealed in polythene bags and stored for 2, 7, 14, 21 and 35 days at $19{^{\circ}C}$. The urease sources, their levels and treatment time produced significant effects on ammonia production (p<0.01). The addition of urease offered more flexibility in hydrolyzing urea in the shortest possible time. Incorporation of soya bean and jack bean meal was effective in reducing the modified acid detergent fiber (MADF) content of straw and the same time increasing organic matter (OM) digestibility. Overall effect, addition of soya bean to urea at a ratio of 1:1 appeared to be the most satisfactory urease source for the treatment of urea and wheat straw.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.6
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• pp.880-892
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• 2009

An overflow of information leads consumers to be easily distracted and to neglect the information being provided to them. E-tailers have to select types of information sources and provide their consumers with the most appropriate information. This study was done to specifically contribute to the research in proposing strategies of providing information of the Internet merchant to the e-shoppers through the analysis of relationships among the online purchase motives of consumers, the use of information sources, and decision making styles. This research categorizes the use of information sources into information sources concerning online stores and information sources concerning products. The uses of information sources relative to online stores are classified into the neutral, human, and marketer-oriented sources. The uses of information sources concerning the products are classified into the online and offline source. This study provides important suggestions for e-tailers to provide information about stores as well as products to the consumers with adaptable strategies.

• Preventive Nutrition and Food Science
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• v.17 no.4
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• pp.254-260
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• 2012

This study surveyed dietary intake and adherence to the Korean national dietary guidelines in Korean adolescents. To elucidate basic data for use in nutrition education, which aims to improve adolescent compliance with the national dietary guidelines and to increase the intake of dietary fiber, we evaluated the sources of fiber in adolescent diets. This study included 182 male and 212 female students from 2 middle schools in the Jeonju province. From November 15~20, 2011, we surveyed the students for general characteristics, adherence to the Korean national dietary guidelines, and dietary intake. Dietary fiber intake was $16.57{\pm}6.95$ g/day for male students and $16.14{\pm}7.11$ g/day for female students. The food groups that contributed most to dietary fiber intake were (in descending order) cereals, vegetables, seasoning, and fruits. The fiber-containing food items consumed most were cabbagekimchi, cooked rice, instant noodles, and cabbage. Based on adherence to the Korean national dietary guidelines, the vegetable-based intake of dietary fiber in groups 1 (score 15~45), 2 (score 46~52), and 3 (score 53~75) were $4.41{\pm}2.595$ g/day, $4.12{\pm}2.692$ g/day, and $5.49{\pm}3.157$ g/day, respectively (p 0.001). In addition, the total intake of dietary fiber varied significantly among the three groups (p 0.001) as follows: Group 1, $14.99{\pm}6.374$ g/day; Group 2, $15.32{\pm}6.772$ g/day; and Group 3, $18.79{\pm}7.361$ g/day. In this study, we discovered that adherence to the Korean national dietary guidelines correlates with improved intake of dietary fiber. Therefore, marketing and educational development is needed to promote adherence to the Korean national dietary guidelines. In addition, nutritional education is needed to improve dietary fiber consumption through the intake of vegetables and fruits other than kimchi.

• Journal of the Optical Society of Korea
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• v.15 no.3
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• pp.222-226
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• 2011

We demonstrated the feasibility of an amplified wavelength-division multiplexed passive optical network (WDM-PON) architecture based on broadband light source (BLS) seeded optical sources and a novel bidirectional reach extender. Our bidirectional reach extender could provide an amplification of both downstream and upstream signals as well as a BLS output for the upstream WDM signal generation. An error-free 1.25 Gb/s signal transmission over a 100-km long single-mode fiber was achieved in a bidirectional WDM-PON using BLS seeded reflective semiconductor optical amplifier (RSOA) sources.

• 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.

• Asian-Australasian Journal of Animal Sciences
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• v.4 no.3
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• pp.211-218
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• 1991

The effects of dietary fiber on true digestibility of amino acids by growing pigs were studied, using semi-purified diets formulated from alfalfa meal, cassava leaf meal, rubber seed meal and leucacna meal at 20% level. A protein-free diet including 5% cellulose was formulated for correcting the endogenous amino acid loss. Across all the diets, arginine was the most digestible while the least at ileal level was threonine; methionine and/or histidine at fecal level respectively. The true digestibility value of amino acids at ileal level were higher than at fecal level except control diet (cellulose). The true digestibility values at ileal level were similar for all diets but differed at fecal level in different magnitude. These results indicate that undigestible compound in individual feedstuff might confound. True digestibility should be studied together for accurate diet formulation as apparent digestibility decreased when their amino acid concentration in the diet was reduced.

• The Korean Journal of Food And Nutrition
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• v.11 no.5
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• pp.488-492
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• 1998

This study was performed to investigate the influcence of various dietary fiber sources in Korea for activities of bacterial enzymes (${\beta}$-glucosidase, ${\beta}$-glucuronidase) and amounts of putrefactive product (indole) in aged rats. ${\beta}$-Glucosidase activity in the intestinal content was significantly lower in the seamustard 15% group than in other groups whereas the activity of ${\beta}$-glucuronidase was higher in the mugwort 15% group than other experimental groups. The amount of indole and pH in the intestinal content of aged rats were significantly lower in mugwort groups than in other groups.

• Journal of the Optical Society of Korea
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• v.2 no.1
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• pp.22-25
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• 1998

We present a spectrum broadening technique to improve the signal-to-noise ratio of spectrum sliced incoherent light sources using the fiber four-wave mixing effect which occurs in a nonlinear loop mirror located at the receiver. The initial transmission channel bandwidth of 0.92 nm was increased to 1.62 nm in the nonlinear loop mirror at the optical receiver, which enhances the signal-to-noise ratio to a desired value. Using this technique, we have demonstrated the transmission of a 2.5 Gb/s NRZ signal with the 0.92 nm bandwidth through a 80 km dispersion-shifted fiber. The measured transmission penalty was less than 0.2 dB at $1{\imes}10^{-10}$ BER.

• Journal of Ocean Engineering and Technology
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• v.16 no.2
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• pp.67-71
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• 2002

Damage process of CFRP laminates was characterized by Acoustic Emission (AE). The main objective of this study is to determine if the sources of AE in CERP laminates could be identified from the characteristics of the waveform signals recorded during monotonic tensile test. The time history and power spectrum of each individual wave signal recorded during test were examined and classified according to their special characteristics. The wave from and frequency of AE signal from a specimens is an aid to the determination of the extent of the different fracture mechanism such as matrix crack, debonding, fiber pull-out and fiber fracture as load is increased. Four distinct types of signals were observed regardless of specimen condition. The result showed that the AE method could be effectively used for analysis of fracture mechanism in CFRP laminates.