• Korean Journal of Ichthyology
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• v.25 no.4
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• pp.189-199
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• 2013

The distribution status and habitat characteristics of the endangered species, Lethenteron reissneri were investigated in 2011~2012 in Korea. During the study period, L. reissneri were collected 60 stations among 755 sampling stations investigated. The total numbers of ammocoetes and adults were 208 and 435, respectively from eight stations of the Han River drainage system, four stations of Geum River drainage system, 32 stations of Seomjin and Yeongsan River drainage systems, and 16 stations of Nakdong River drainage system. The Han and Geum river drainage systems, the Sapkyo Stream and independent streams running toward the East Sea were estimated to have suffered sudden reductions of population density, whereas the Seomjin River drainage system showed increased population density compared with historic occurrence records. L. reissneri inhabited the middle-upper stream of clean water with well-developed rapids and lots of aquatic organisms. According to IUCN Red List categories and criteria L. reissneri was assessed to be vulnerable (VU) [B2ab (ii,iii,iv,v);D1] because of the rapid reduction of the occupying areas and the small number of mature individuals. Besides the distribution status and habitat characteristics we discussed the conservation strategies of L. reissneri.

• Journal of Agricultural Extension & Community Development
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• v.20 no.1
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• pp.265-297
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• 2013

This study performed quality study to examine cognition and experience as it is about husband role of wife's perception in rural multicultural family. Specifically the results of in-depth interviews with 13 females in rural multicultural family was analyzed through phenomenological method. The results were as followings: first, wife's cognition about husband role in rural multicultural family, they were 'nice and warm man', 'no special thought', 'clean and cool looking man', 'man without straitening wife', 'husband taking care of housekeeping', 'having independent family' and 'strong responsibility to children'. Females in rural multicultural family did not deeply think about husband's role at international marriage, but it could be known that vague longing for rich country, Korea by Korean wave and its expectation continued to expectation on husband. Second, they were 'good-tempered and nice to me', 'adjust to me', 'irresponsibility and apathy', 'cannot lean to him', 'no housekeeping', 'intermediate role between his family', 'more taking care of children, parents and relatives', 'drink, gambling and violence'. The experience of husband role was little different from cognition of husband role by females in rural mulitcultural family.

• Korean Journal of Community Nutrition
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• v.17 no.2
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• pp.167-181
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• 2012

Our society is aging rapidly, and the number of elderly people who are in charge of purchasing and preparing foods at home is increasing. However, most the elderly have difficulty managing nutrition and food safety by themselves. The purpose of this study was to develop the necessary knowledge, through focus group interview and Delphi technique to establish a food safety and nutrition education program. The diet and educational needs of the elderly were surveyed through FGI. The education topics were decided by the Delphi technique. The education program consisted of a five week program, and the topics taught were 'Dietary Change for Healthy Life', 'Prevention of Food Poisoning in Everyday Life', 'Safe Food Handling for my Health', 'Healthy Dietary Life to Prevent Chronic Disease', and 'Safety! Nutrition! Healthy Dietary Life'. This education program was designed to decrease the perceived barriers, and to increase the perceived interests and the sense of self-efficacy. Education program materials, lesson plans, slides, handouts, videos, leaflets, and booklets were developed. Based on the results, the contents of the food safety guideline leaflets for the elderly were decided as the following: (1) wash your hands in the correct way; (2) select safe food; (3) cook foods safely; (4) keep foods safely; (5) keep kitchen utensils clean. In conclusion, if advanced education programs are implemented and delivered continuously in locations such as health centers and community welfare centers, those will contribute significantly to enhance the perception of food safety and to change the desirable dietary behavior of the elderly.

• Korean Journal of Community Nutrition
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• v.24 no.6
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• pp.497-511
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• 2019

Objectives: This study aimed to develop a school-centered healthy eating environment for children in elementary care classrooms and prevent incorrect eating habits and obesity through the development and application of standardized healthy eating habit-forming educational materials. Methods: Ten schools in eight districts of Gyeonggi-do and 400 students from 19 care classes were selected. Based on the developed educational materials, the program was applied to students once in two weeks. 'Notices for Parents' forms were also sent to the students' home to educate their parents. Pre and post-surveys were conducted to evaluate the effectiveness of the education. The pre-education, education, and aftercare were conducted from September 28 to September 31, 2016, from October 3 to November 30, 2016, and from December 5 to December 9, 2016, respectively. Results: The healthy eating program for elementary care classes was designed to develop a school-centered healthy eating environment and provide standardized educational material for healthy eating habits. Twelve educational topics were developed: , , , , , , , , , , , and . Moreover, the materials were produced in four forms: for students, for after school caring teachers, for external specialists, and for parents. The effectiveness evaluation was conducted to confirm the application of the program. The average eating habits score was 3.3 ± 0.6, with no significant difference between before and after application. The score of overall satisfaction of the education was 3.9 ± 0.9. The most satisfying content was 'Did you get to know how to eat evenly?'. Significant increases were observed in two contents for parents regarding their children's knowledge changes after the education: 'Five nutrients needed for growing children' and 'Knowing sugar foods and sugar-containing foods'. On the other hand, their educational satisfaction was 3.6 ± 0.6, which was lower than the children's satisfaction. This might be because their education was conducted only through the 'Notices for Parents' form. Conclusions: In the long term, the healthy eating habit-formation education for lower elementary school children is expected to be beneficial. To prevent obesity and establish healthy eating habits of children, it is important to develop healthy eating education programs centered on elementary school aftercare classes, including the development of educational materials and an application system through connection with the home and community.

• Korean Journal of Agricultural Science
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• v.47 no.3
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• pp.605-614
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• 2020

This study was conducted to compare the growth performances of three groups of commercial Korean native chickens (KNCs) including two strains of crossbreeds and H3 (Hanhyeop 3) from hatch to twelve weeks of age. (1A, 2A, and H3). A total of 468 one-day-old chicks were allocated in a completely randomized design with 15 replicates per treatment for the crossbreeds and 9 replicates per treatment for H3 (12 birds per cage). Commercial broiler diets (i.e., Week 0 - 5 crude protein [CP] 22.0%, metabolizable energy [ME] 3,025 kcal·kg^-1; week 5 - 8 CP 20.0%, ME 3,100 kcal·kg^-1; week 8 - 12 CP 19.0%, ME 3,150 kcal·kg^-1) were provided according to the Korean Feeding Standard for Poultry on an ad-libitum basis with fresh clean water during the twelve-week period. Body weight gain and shank length (SL) were measured weekly until week 6 and bi-weekly during week 6 to 12. Compared to H3, the two crossbreed groups had a higher body weight (BW) on weeks 3 to 8; however, the bodyweight of H3 on week 10 was significantly higher than the other groups (p < 0.05). Moreover, the average daily feed intake (ADFI) of H3 was higher than that of the two crossbreed groups from hatching to 84 days except for week 3, and H3 showed a lower average daily gain (ADG) on weeks 3 and 10 (p < 0.05). Furthermore, H3 had a higher feed conversion ratio compared to another crossbreed chicken on weeks 1 to 8 and the last week after hatching. Among all the groups, there was no significant difference for shank length during the experimental period.

• Journal of Dental Rehabilitation and Applied Science
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• v.32 no.4
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• pp.263-273
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• 2016

In the implant prosthetic procedure, the soft tissue reaction was varied with the material and surface treatment of the abutment. It may be the cause of the peri-implantitis, and hence it can affect the long-term prognosis of the implant prosthesis. Titania and zirconia abutment presented superior biocompatibility and stable soft tissue reaction, while gold alloy abutment showed unfavorable reaction sometimes. A soft tissue reaction can be differed by the surface characteristics even in the same material type. Because rougher surface induces a bacterial attachment, the part contacting a soft tissue should have smooth surface. Additional surface treatment can enhance the cellular response without increasing bacterial attachment. Repeated removal and insertion of the abutment and the shape of the abutment may affect the soft tissue reaction, also. Ultrasonic cleaning and argon plasma cleaning are effective way to clean the retained micro-dust on the customized abutment.

• Journal of Adhesion and Interface
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• v.19 no.3
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• pp.101-105
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• 2018

With the rapidly growing of the population and industrization of cities, the clean and affordable water resources have gained immense interest because of remaining about 780 million people still lack access to it. However, present wastewater treatment systems have been faced with various issues, such as low processing efficiency, high operational costs and the requirement of a large area for manufacturing. It is therefore urgently required to develop an inexpensive and efficient wastewater treatment system. As the one of these efforts, we suggested and successfully demonstrated the wastewater treatment system using and electrochemical method via a dimensionally stable anode (DSA) based on rutile type $RuO_2$. Our system achieved biochemical oxygen demand (BOD), chemical oxygen demand (COD), and total organic carbon (TOC) removal efficiently at the respective rates of 52.0%, 77.8%, and 65.6% from household wastewater. In addition, we were able to remove BOD, COD, total nitrogen (TN), and total phosphorus (TP) from animal husbandry wastewater at rates of 92.9%, 75.6%, 35.1%, and 100%, respectively, thereby achieving dramatic reductions. Considering the excellent removal efficiency and the small size of this device, electrochemical wastewater treatment using a DSA coated in rutile $RuO_2$ presents a promising option for the treatment of both household and animal husbandry wastewater.

• Journal of the Korean Vacuum Society
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• v.18 no.1
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• pp.15-23
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• 2009

Saturation-coverage silyl, $-SiH_3(a)$, overlayers were prepared from $Si_2H_6$ adsorption on three comparative surfaces: clean unmodified; D-precovered; and atomically roughened Si(100). Together with its precursor-mediated adsorption behavior, the surface reactivity of $Si_2H_6$ was found to be the highest on the unmodified Si(100)-$2{\times}1$ surface. This was correlated with its dissociative adsorption mechanism, in which both the $H_3Si-SiH_3$ bond scission and the dual surface $Si-SiH_3(a)$ bond formation require a surface dangling bond 'pair'. The unusually high thermal stability of $-SiH_3(a)$ on the unmodified surface was ascribed to a nearly close-packed $-SiH_3(a)$ coverage of ${\sim}0.9$ monolayer and the consequent lack of dangling bonds on the silyl-packed surface.

• Journal of the Korean Vacuum Society
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• v.17 no.4
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• pp.270-277
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• 2008

Vacuum is any air or gas pressure less than a prevailing pressure in an environmental or, specifically, any pressure lower than the atmospheric pressure and is used by a wide variety of scientists and engineering - including clean environment, thermal insulation, very long mean free path, plasma, space simulation[1]. The space environment is characterized by such a severe condition as high vacuum, and very low and high temperature. Since a satellite will be exposed to such a space environment as soon as it goes into its orbit, space environmental test should be carried out to verify the performance of the satellite on the ground under the space environmental conditions. A general and widely used method to simulate the space environment is using a thermal vacuum chamber which consists of vacuum vessel and thermally controlled shroud. As indicated by name of vacuum chamber, the vacuum technology is applied to design and manufacture of the thermal vacuum chamber. This paper describe the vacuum technology which is applied to space business.

• Korean Journal of Microbiology
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• v.45 no.4
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• pp.354-361
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• 2009

This study was carried out to develop an effective biocarrier-mediated bioaugmentation technology which will be useful for remediation of the crude oil-contaminated marine sediments. Enrichment of several microbial communities was made from several oil-polluted seashore sites and the two distinctively functional consortia have been successfully selected. These two consortia were grown together and used to manufacture the microbial agents for bioaugmentation of marine sediments polluted with crude oil. The most dominant species in the mixed culture was identified as Alcanivorax borkumensis based on pure culture and DGGE analysis. Bioaugmentation of oil-polluted marine sediments with the microbial agent MA-2 formulated using the mixed culture and biocarriers (activated carbon and minerals) was more effective, especially in combination with an oxygen producing (releasing) compound (ORC). Ninty percent of TPH was removed in the presence of ORC in 35 days while 74% in the absence of ORC. This indicated that the indigenous consortial degraders could be immobilized on the active carbon as a biocarrier to manufacture microbial agents and then effectively bioaugmented for remediation of the oil-polluted sediments.