• Korean Journal of Materials Research
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• v.9 no.12
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• pp.1170-1175
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• 1999

The microstructures and mechanical properties of $Si_3N_4$ ceramics produced by nitridation and post-sintering using semiconductor-waste-Si sludge were investigated. Lots of microcracks were observed in the waste-Si powders which contained some amounts of amorphous $SiO_2$. The nitridation rate of waste-Si compacts showed lower value than that of commercial Si powder compacts. The nitridation rate was increased with increasing nitridation temperature and then the percent of nitridation at 1470$^{\circ}C$ showed 98%. The phases of $Si_3N_4$ in the reaction-bonded bodies were mixed with ${\alpha}$ and ${\beta}$-type, and small amounts of $Si_2N_2O$ phase while those after post-sintering were ${\beta}$-$Si_3N_4$ and ${\alpha}$-Sialon. The sample post-sintered at 1950$^{\circ}C$ showed the fracture toughness of 5.6 $^MPa{\cdot}m^{1/2}$ and the fracture strength of 497 MPa which were lower than those of sintered body using commercial Si powder possibly due to the formation of ${\alpha}$-Sialon phase.

• The Korean Journal of Mycology
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• v.18 no.4
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• pp.225-232
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• 1990

In order to find an useful condition under which the mutants defective in sexual development could be isolated, the effects of several cultural conditions on the developments of Aspergillus nidulans were examined. Among several conditions found to restrict the asexual sporulation but enhance the sexual process, the interference of aeration by sealing the plates with sealing film was the most useful one for the purpose of mutant isolation. Sealing at any time before 20 hours from inoculation prevented both sexual and asexual process. When the seal was removed after 24 hours, however, the mycelia developed only to sexual organs. Using this properity, the early morphogenic process of sexual development could be easily observed and a number of mutants that showed some defects in the process could be isolated. The mutants were divided into 3 groups, NSD (never in sexual development), BSD (block in sexual development) and ASD (abnormal in sexual development). NSD mutants never produced either the $H{\ddot{u}}lle$ cells or cleistothecia and some produced the asexual organs even when the aeration was restricted. BSD mutants were blocked in the process of $H{\ddot{u}}lle$ cell, cleistothecia, crozier, asci or ascospore formation. ASD mutants had defects in the amount of cleistothecia, time of cleistothecial maturation or color of ascospores.

• Korean Journal of Plant Tissue Culture
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• v.25 no.3
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• pp.177-181
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• 1998

This study was carried out to investigate activity difference in the superoxide dismutase (SOD) and peroxidase (POD) of tomato callus transformed with Agrobacterium containing the GUS gene. Than those of other two tomato cultivars, the hypocotyl explant of JA101 was shown to have higher POD and SOD specific activity of 23 unit/mg protein and 2,156 unit/mg protein, respectively. Relatively high frequency of callus formation was obtained from the hypocotyl explant on MS medium containing 1 mg/L 2,4-D for 30 days and its POD(47 unit/mg protein) and SOD (95,786 unit/mg protein) specific activities were higher than other 2,4-D concentration. The hypocotyl explant and callus cocultivated with Agrobacterium for 72 hours were transferred to MS medium supplemented with 1 mg/L 2,4-D, 30 mg/L kanamycin, 30 g/L sucrose and 4 g/L Gelrite. The hypocotyl explants transferred to the medium formed callus with 45.5% effeciency after 8 weeks. The transformation efficiency confirmed by GUS assay was 21.6%. POD specific activity of the transformed callus (54 unit/mg protein) were somewhat lower than the non-transformed callus (64 unit/mgg protein) and SOD specific activity of the transformed callus (30,300 unit/mg protein) were also lower than the non-transformed callus (37,077 unit/mg protein). However there was no significant difference in POD and SOD isozyme patterns between the transformed and the non-transformed calluses. From these results, it revealed that there was no difference of antioxidant enzyme activities between the transformed callus and the non-transformed callus in tomato.

• Parasites, Hosts and Diseases
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• v.29 no.4
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• pp.389-396
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• 1991

Antibody changes in experimental anisakiasis were observed in 10 rabbits which were infected each with 10 Anisakis simplex larvae. The sera were collected before and on the 6th to the 95th day after the infection. Using crude saline extract of Anisakis larvae as antigen, specific IgM and IgG antibody levels were observed by ELISA and SDS-polyacrylamide gel electrophoresislimmunoblot. Levels of specific-IgM antibody were elevated from the 6th day, reached their peaks on the lIth day after the infection, and dropped thereafter. Serum levels of IgG antibody increased from the 6th day and reached their peak on the 26th day after the infection, and decreased gradually thereafter. When SDS-PAGE of the crude extract was done, at least forty-one SDS-polypeptide bands were recognized. Of them, IgM antibody reacted mainly to the bands of 168, 95, 74, 64, 51, 47 and 34 kDa while IgG antibody reacted strongly to 168, 92, 85, 64, 58, 52, 42 and 40 kDa bands. The crude extract showed negligible cross reactions with sera of other parasitic diseases and normal control. Key words: Anisakis simplex larvae, experimental anisakiasis, rabbit, antibody, ELISA, SDS- PAGE/immunoblot.

• Korean Journal of Acupuncture
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• v.37 no.1
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• pp.31-36
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• 2020

Objectives : The purpose of this study is to review needling depth and location of LU7, BL62 and KI6 by the medical classics' records. Methods : 1. We researched the medical classics describing LU7, KI6 and BL62, and reorganized data about the location and needling depth. 2. We compared the medical classics' records on LU7, KI6 and BL62 with description of WHO standard acupuncture point location. 3. We reviewed different location and needling depth of LU7, BL62, and KI6 recorded in the medical classics with the anatomical structure. Results : 1. The common needling depth of LU7 is about 0.2 chon. But in some medical classics, the depth of LU7 is 0.8 chon. Needling depth of LU7 varied depending on the patient's hand posture. In the 'half-up' position with the thumb upward, it is possible to stimulate acupuncture on LU7 by 0.8 chon because there is a space between the tendons. 2. In WHO standard acupuncture point location, the locations of BL62 and KI6 are just below the lateral and medial malleolus. But in some medical classics, the locations of BL62 and KI6 are between the bones and muscles below the malleolus. In the locations between the bones and muscles below the malleolus, it is possible to stimulate acupuncture on BL62 and KI6 by penetrating acupuncture because there is no bone structure. Conclusions : 1. By the 'half-up' position with the thumb upward, it is possible to stimulate vertically acupuncture on LU7 by 0.8 chon. 2. By the locations of BL62 and KI6 between the bones and muscles below the malleolus, it is possible to stimulate on BL62 and KI6 by penetrating acupuncture.

• The Journal of Korean Medical History
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• v.32 no.2
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• pp.43-50
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• 2019

The medical book Yosandangsinjipeuibangkeumnangjibo (『樂山堂新集醫方錦囊至寶』, below as Yosandang, 『樂山堂』) is housed in the Handok museum of Medicine and Pharmacy. At the end of the Yosandang, written in manuscript, contains a rhymes of herbal medicine (藥性歌). The rhymes of herbal medicine is a record of song form about herbal medicine. Song-forms were widely used because they were easy to sing and memorize. In particular, there are many records of song forms in Korean medical books, which have been used in various fields such as herbal medicines, acupuncture points, and diagnosis. Although Yosandang is not a widely known medical book, it is meaningful in that it shows a cross section of late Joseon Korean medicine. So, this paper considers rhymes of herbal medicine in Yosandang. Yosandang is a medical book of the late Joseon period written by doctor Byun Gwangwon in 1806. This book consists of 6 books and 14 volumes, 13 of which are rhymes of herbal medicine. The rhymes of herbal medicine in Yosandang is 7 words-2 phrases form for the first time in Korea. This is almost 80 years earlier than the same form of Bangyakhabpyeon (『方藥合編』). The first part of rhymes of herbal medicine in Yosandang is considered to refer to the rhymes of herbal medicine in Jejungsinpyeon (『濟衆新編』), and the last part seems to be based on the contents of Donguibogam (『東醫寶鑑』). In other words, rhymes of herbal medicine in Yosandang could be considered as the result of trying to contain herbal medicine knowledge as a new 7 words-2 phrases form based on the Jejungsinpyeon (『濟衆新編』) and Donguibogam (『東醫寶鑑』). Unlike the previous rhymes of herbal medicine made during the compilation of medical books led by the late Joseon government, the rhymes of herbal medicine in Yosandang is a new type of rhymes created based on individual efforts in the early 19th century. It has a medicine historical significance in that it can show some aspects of Korean medicine in the late Joseon period.

• Korean journal of food and cookery science
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• v.19 no.5
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• pp.616-623
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• 2003

Waxy barley brans were collected during the pearling process. The extraction of $\beta$-glucan from barley bran was effected by the extraction conditions. The $\beta$-glucan content increased with temperature, but not with pH. The highest yield, 6.5%, was achieved at pH 7.0 and 55$^{\circ}C$. At pH 10 and 45$^{\circ}C$, 48.5% of the $\beta$-glucan in barley bran was recovered in the gum product, with 54.6% purity. The protein and starch contaminations were high, reaching 13.6 and 23.7%, respectively. The $\beta$-glucan content was greatest in the subaleurone and aleurone regions (bran fractions 1, 2, 3 and 4), and declined considerably toward the inner layers. A monosaccharide analysis of the purified, $\beta$-glucan, from bran fractions 1, 2, 3 and 4, indicated that glucose constituted the majority of the gum. The small amounts of the arabinose and xylose found in the gum may indicate the presence of arabinoxylans as minor constituents. The molecular weights of the $\beta$-glucans isolated from bran fractions 1,2 and 3 were found to be 4.09${\times}$10$^{5}$ ∼-4.41${\times}$10$^{5}$ . The major glycosidic linkages of the $\beta$-glucans demonstrated the presence of 2, 4, 6-Me-Glc and 2, 3, 6-Me-Glc. When flow behaviors of barley bran $\beta$-glucan were examined, $\beta$-glucan exhibited pseudoplastic fluid properties.

• Journal of Nutrition and Health
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• v.46 no.2
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• pp.166-176
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• 2013

The purpose of this study was to investigate consumption of health functional food (HFF) and dietary habits, nutrient intake, and dietary quality by HFF consumption in college students. The subjects of this study included 283 college students (179 males and 104 females) in Incheon metropolitan city. The cross-sectional study was conducted using self-reported questionnaires, including kinds of HFF consumed, motivation for purchase, reason for consumption, effect after consumption, reason for no consumption, and dietary habits. A three-day recall method was used for dietary assessment. Dietary qualities were assessed using nutrient adequacy ratio (NAR), mean adequacy ratio (MAR), and nutrient density (ND) values. The percentage of HFF consumption was 40.2% in males and 50.0% in females. The main kinds of HFF consumed by males were vitamins and minerals, red ginseng, protein, and omega-3 fatty acid, in that order. HFF consumed by females were vitamins and minerals, red ginseng, omega-3 fatty acid, and individually approved functional ingredients, in that order. The main motivation for purchase of HFF was recommendation of family and relatives (males 76.4% and females 78.8%). The main reason for consumption of HFF was health promotion (males 67.7% and females 63.5%) and the main reason for no consumption of HFF was not having a health problem (males 49.5% and females 46.2%). The dietary habit score for 'eat the milk or dairy product everyday' (p < 0.05) in females was significantly higher in HFF consumers, compared to HFF non-consumers. In males, the ND of vitamin B1 (p < 0.05) in HFF consumers was significantly higher compared to HFF non-consumers. In females, HFF consumers showed a significantly higher ND of vitamin B2 (p < 0.05) and Ca (p < 0.01), compared to HFF non-consumers. Regardless of HFF consumption, the NAR of vitamin C, folic acid, and Ca was less than 0.7. These results suggest the need for nutrition education for college students in order to improve dietary habits and for balanced nutritional status, and to provide correct information on HFF.

• Journal of the Korean Geotechnical Society
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• v.36 no.5
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• pp.25-34
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• 2020

Studies on nondestructive evaluation methods using electromagnetic waves have been commonly conducted to evaluate necking defects in bored piles. However, the propagation of electromagnetic waves are affected by water contents of surrounding materials. This study aims to investigate a suitability of electromagnetic waves for evaluating necking defects in bored piles embedded in sandy soils through laboratory experiments. Laboratory experiments are performed with a model pile having a necking defect. The diameter and length of model pile are 600 mm and 1 m, respectively, and the model pile is embedded in sandy soils with different water contents of 10%, 20%, and 30%. For the propagation of electromagnetic waves, a transmission line is configured in reinforcement cage using an electrical wire. The generation and detection of electromagnetic waves are conducted using a time domain reflectometer. Experimental results show that the peak amplitude of electromagnetic waves reflected at the necking defect decreases with an increase in the water content in sandy soils. In addition, the velocity of electromagnetic waves reflected from the toe of the model pile decreases win an increase in the water content. However, estimated locations of the necking defects are almost the same to that of the actual location of the necking defect. This study demonstrates that electromagnetic waves may be an effective method for evaluating necking defects in bored piles embedded in sandy soils

• Korean Journal of Construction Engineering and Management
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• v.9 no.3
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• pp.206-213
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• 2008

Due to the following reasons, the management of curtain wall parts and material is very Important. Firstly, curtain wall work is one of the main works in High-rise building construction for it takes about $10{\sim}15%$ of the total construction cost. Secondly, the whole process of curtain wall work including manu acture, delivery, storage, installation and maintenance is very complicated and sometimes more than 30 companies involve in the process. Thus there are many control points for curtain wall units. Thirdly, there are not enough space on site for material storage and this situation is more serious for sites in urban area. The purpose of this research is to validate an information systems using RFID technology that is developed to manage the curtain wall units following the process of curtain wall work. For the validation, the cycle times of curtain wall work before and a ter the system was used. The results show that using the systems shorten the cycle time of the curtain wall work. Thus it is concluded that the system can increase the efficiency of managing curtain wall work.