• The Journal of Korean Academy of Prosthodontics
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• v.48 no.1
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• pp.55-60
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• 2010

Purpose: The shrinkage of dental resin cement may cause several clinical problems such as distortion that may jeopardize the accurate fit to the prepared tooth and internal stress within the restorations. It is important to know the polymerization shrinkage-strain of dental resin cement to reduce clinical complications. The purpose of this study was to investigate the polymerization shrinkage-strain kinetics of six commercially available dental resin cements. Material and methods: Three self-cure resin cements (Fujicem, Superbond, M-bond) and three dual-cure resin cements (Maxcem, Panavia-F, Variolink II) were investigated. Time dependent polymerization shrinkage-strain kinetics of the materials were measured by the Bonded-disk method as a function of time at $23^{\circ}C$, with values particularly noted at 1, 5, 10, 30, 60, 120 min after mixing. Five recordings were taken for each materials. The data were analyzed with one-way ANOVA and Scheffe post hoc test at the significance level of 0.05. Results: Polymerization shrinkage-strain values were 3.72%, 4.19%, 4.13%, 2.44%, 7.57%, 2.90% for Fujicem, Maxcem, M bond, Panavia F, Superbond, Variolink II, respectively at 120 minutes after the start of mixing. Panavia F exhibited maximum polymerization shrinkage-strain values, but Superbond showed minimum polymerization shrinkage-strain values among the investigated materials (P < .05). There was no significant differences of shrinkage-strain value between Maxcem and M bond at 120 minutes after the start of mixing (P > .05). Most shrinkage of the resin cement materials investigated occurred in the first 30 minutes after the start of mixing. Conclusion: The onset of polymerization shrinkage of self-cure resin cements was slower than that of dual-cure resin cements after mixing, but the net shrinkage strain values of self-cure resin cements was higher than that of dual-cure resin cements at 120 minutes after mixing. Most shrinkage of the dental resin cements occurred in the first 30 minutes after mixing.

• Journal of The Korean Association For Science Education
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• v.37 no.4
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• pp.747-761
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• 2017

The purpose of this study is to analyze differences in the teaching practices of biology teachers according to their awareness of the importance of evolution. For this purpose, two teachers who experienced study of evolution and recognized its importance, along with two teachers with no experience in evolution education in the comparison group, were included in the sample. To observe teaching practices, two classes each on biological evolution and non-evolution were selected, recorded and transcribed. The content analyzed included the teachers' view on evolution education and teachers' evolution concepts reflected in teaching practice. As a result, the level of understanding of the teachers' evolution concept was unrelated to teachers' awareness of the importance of evolution. Instead, each teacher would not feel the need for religious beliefs or awareness of the importance of evolution to have a negative impact on the awareness of the importance of evolution. Inexperienced teachers tend to reject the retraining opportunities to recognize the importance of evolution. In addition, inexperienced teachers were only superficially aware of the evaluation and improvement of evolution presented in textbooks and curricula. In actual teaching practice analysis, inexperienced teachers' utilizing ratio of the evolution key concept was higher than that of experienced teachers. Only experienced teachers were aware of the misconceptions presented in their execution and described the causes that appear in these misconceptions. Teachers who recognized the importance of evolution were widely using the key concepts of evolution, as well as more practical in preventing the misconceptions related to evolution forms. It indicates that biology teachers who do not realize the importance of evolution in biology education need to experience explicit and practical education programs as well as instructional materials on evolution.

• Journal of Aquaculture
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• v.21 no.1
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• pp.26-33
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• 2008

This study investigated the synergistic effects of dietary supplementation of quartz porphyry(QP) and a laboratory developed feed stimulants, BAISM(BS) on growth performance and utilization as the additives for juvenile eel Anguilla japonica. Six isoenergetic experimental diets(18.2 kJ/g) were formulated to contain 50% crude protein, 15% lipid with or without dietary QP(Song-Gang stone, Davistone, Korea) and BS supplementation. QP and BS were provided at 0% in the control diet($Q_0B_0$) and at 0.7% QP+0% BS($Q_{0.7}B_0$), 0.7% QP+0.3% BS($Q_{0.7}B_{0.3}$), 0.7% QP+0.5% BS($Q_{0.7}B_{0.5}$), 0.7% QP+0.75% BS($Q_{0.7}B_{0.75}$) and 0.7% QP+1.0% BS($Q_{0.7}B_{1.0}$) in experimental diets on dry matter basis. After four weeks of adaptation, triplicate groups of 30 fish initially averaging $15{\pm}0.1g(mean{\pm}SD)$ were randomly distributed into each aquarium, and they were fed one of the experimental diets for 8 weeks. By the end of the feeding trial, weight gain(%), specific growth rate(%), feed efficiency(%) and protein efficiency ratio of fish fed diet $Q_{0.7}B_{0.5},\;Q_{0.7}B_{0.75}\;and\;Q_{0.7}B_{1.0}$, were significantly higher(P<0.05) than those of fish fed the other diets. But, $Q_{0.7}B_{0.5},\;Q_{0.7}B_{0.75}\;and\;Q_{0.7}B_{1.0}$ were no significant differences(P<0.05). In challenge test, fish were infected by intraperitoneal injection of 0.1 mL bacterial suspension with Edwardsiella tarda per fish after the feeding trial. As a result, fish fed QP and BS supplemented diets have a significantly higher cumulative survival rate than those of fish fed control diet(P<0.05). In conclusion, these results indicated that the optimum dietary supplementation level of QP and BS could be approximately 0.7% quartz porphyry+0.5% BAISM($Q_{0.7}B_{0.5}$) of diet based on WG, FER, SGR, PER, cumulative survival rate in juvenile eel A. japonica.

• Korea journal of population studies
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• v.19 no.2
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• pp.175-205
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• 1996

The purpose of this study was to find the distribution of the variables on the quality of life and the determinants of the sexual attitude and behavior of the unmarried female workers. This study was surveyed to the 306 unmarried women who worked in the small and medium scale industries in Kyungin area and analyzed the respondent's knowledge of sex, sexual behavior, health behavior, health status, satisfaction of working condition and recognition of working environment. The result of this study could be summarized as follows: The respondent's age are mostly early of twenties and their education level are high school and more. They recognize that their health condition is not so good but they hardly try to improve health condition. They think that their working condition are mostly unsatisfied and they also believe that they expose themselves to the toxic working environment. Although their knowledge of sex are low they have few chances for the education of sex and family planning. Their attitude of premarital sex are conservertive but the rate of approval of living together before marriage are high and the rate of premarital sex is around 15 percent. The premarital sex behavior are positively related with family size, living condition, knowledge of sex and working period but the sex experiences are negatively related with working period and knowledge of sex. As a result we suggest that the sex education and consultative program are necessary for improving the quality of life of the unmarried working women in small and medium scale industries.

• Food Science and Preservation
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• v.24 no.1
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• pp.93-99
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• 2017

Collagen synthesis is decreased and matrix metalloproteinase-1 (MMP-1) levels are increased in naturally aged human skin, and these alterations cause changes such as skin wrinkling and decreased elasticity. As a part of our ongoing search for bioactive ingredients, MMP-1 inhibitory and type-1 procollagen synthesis inducing activities of aqueous methanolic extract of manufactured gambir product from Uncaria gambir were investigated in in vitro bioassay systems. In addition, total phenolic contents were quantified using a spectrophotometric method. Among tested samples, 40% MeOH eluate from 80% methanolic extract of manufactured U. gambir using open column chromatography packed with Diaion HP-20 resin showed significant MMP-1 inhibitory activities with an $IC_{50}$ value of $15.6{\pm}1.3{\mu}g/mL$. Furthermore, type-1 procollagen synthesis promoting property of 40% MeOH eluate ($IC_{50}$ value; $6.9{\pm}0.7{\mu}g/mL$) from 80% methanolic extract of manufactured gambir was higher than other eluates. Additionally, the present investigation revealed that 40% MeOH eluate of manufactured gambir product contained a high level of total phenolic compounds. The result suggests a distinct relationship between anti-wrinkle activity and total phenolic contents, and manufactured gambir product could be considered a new effective source of natural bioactive ingredients. Systematic investigation of manufactured gambir product will be performed for further development of its biological properties.

• Journal of the Korean Society for Library and Information Science
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• v.50 no.1
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• pp.437-456
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• 2016

This study, based on the need for department of LIS education program that targets training of subject-special librarian, focuses on proving that such education can improve perception of subject-special librarian and strengthen career decision-making. This study is composed of two parts. First, this study investigates case studies about subject-special librarian cultivation. Second, this study includes a survey about subject-special librarian, improving understanding about subject-special librarian, and improving career decision-making which was carried out targeting students who take 'Medical Terms and MeSH', and 'Health & Medical Information Sources' courses. Results are as follows. First, most of the respondents felt the need for medical librarian and medical information services (88.7%), understood the role of medical librarian (92.5%), got to know more about the types and functions of medical information services (100%), and came to be more aware of the self-esteem a medical librarian feels as a professional. Second, relatively, the percentage of respondents who demonstrated the willingness to work at a medical library (45.3%) or work in the field of medical information services (26.4%) was noticeably low. Third, there were no statistical difference in whether the students took related courses or not, number of courses they took and difference in their school year, and in regard of the level of understanding of medical librarian and medical information services, those who took courses demonstrated higher understanding than did those who did not take those courses. Also, those who took the courses showed stronger willingness to work as a medical librarian. Fourthly, the curriculum carried out by the department of library and information service was effective in understanding medical librarian and medical information services, but makes students more cautious about deciding whether or not to start their career at a medical library. Lastly, it was recommended that there is a need to have the curriculum updated in order to help students overcome the difficulty and unfamiliarity they feel about medical subject.

• Korean Journal of Medicinal Crop Science
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• v.1 no.2
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• pp.137-157
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• 1993

This study was carried out to investigate the optimal condition for multiple propagation through leaf tissue culture and to apply anther culture techniques to Pulsatilla koreana Nakai breeding. Leaf and anther of Pulsatilla koreana Nakai were cultured on MS, MT, LS and $B_5$ media supplemented with several growth regulators and nitrogen sources under various conditions. For callus induction and differentiation from the Pulsatilla koreana leaf segments were more effective in the combination of zeatin and auxin than auxin alone. The color of the callus was green when treated with IBA alone. Shoot differentiation was more effective when treated with zeatin than auxin alone, especially the best hormoal combination for shoot differentiation was zeatin 1.0mg/l +NAA 0.1mg/l, while 2,4-D inhibited shoot differentiation. The appeared rate of S pollen was 35% in vivo, while that of S pollen by low temperature$(4^{\circ}C)$ pretreatment for 4 days was increased by 53% and the optimum culture time for callus induction from anther was uni-nucleate stage. $B_5$ basal medium supplemented with NAA 0.5mg/l and zeatin 1 mg/l was the most effective on callus formation and the best results of plant regeneration were obtained from combination of NAA 0.5mg/l and zeatin 0.5mg/l in anther culture. $NH_{4}NO_3$ as more effectives as the nitrogen source than $KNO_3$ and the combination with zeatin 2.0mg /L was the best effective. The best combination for plant regeneration in callus induced from anther was $NH_{4}NO_3$ 1650mg/l + $KNO_3$ 3800mg/l + zeatin 2.0mg/l. Ploidy level of anther-derived plants appeared 28% haploid, 47% diploid and the others were triploid, tetraploid and mixploid. In compare with E.S.T, M.D.H and P.X banding patterns were distinguished among callus, haploid and diploid plants in electrophoresis.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.3
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• pp.1-11
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• 2012

This study focused on establishing a natural rainwater circulation system using rainwater meant for relatively large urban development projects such as a new town development. In particular, when the location selection techniques for individual elements of a natural rainwater circulation system are developed for the integrated rainwater management, changes in hydrological environment will be minimized and the natural water circulation would be restored to realize the low impact development (LID). In that case, not only the excess will be reduced but water space and green areas in a city would also increase to improve the urban sustainability. First of all, there were five elements selected for the location selection of a rainwater circulation system intended for the integrated rainwater management: rainwater collection, infiltration, filtration, retention and movement spaces. After generating these items, the location selection items and criteria were defined for each of the five elements. For a technique to apply the generated evaluation items and criteria, a grid cell analysis was conducted based m the suitability index theory, and thematic maps were overlapped through suitability assessment of each element and graded based on the suitability index. The priority areas were identified for each element. The developed technique was applied to a site where Gim-cheon Innovation City development is planned to review its feasibility and limitations. The combined score of the overlapped map for each element was separated into five levels: very low, low, moderate, high and very high. Finally, it was concluded that creating a rainwater circulation system conceptual map m the current land use plan based on the outcome of the application would be useful in building a water circulation system at the de1ailed space planning stage after environmental and ecological planning. Furthermore, we use the results of this study as a means for environment-friendly urban planning for sustainable urban development.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.3
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• pp.22-31
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• 2012

This study was prompted by the recognition that the tenn "Community design" has recently been used in diverse practical fields without prior discussion about its underpinnings, a potentially problematic state of affairs. Based on these problems, this study studied the special quality about the concept of community design. Community design can be discussed from two perspectives. The first views community design as a design that concerns the community, an inhabited area populated with people who have common interests, at least in part because of geographic proximity to each other. The second sees community design as a movement that started in the 1960s and places a great importance on democratic decision making, communication, and collaboration. This study will focus on the latter. This branch of community design encompasses an advocacy planning approach, in which design professionals represent deprived communities in their resistance against comprehensive redevelopment. This was associated to the wider social protest movements of the mid and late 1960s. In the 1970s, this branch of community design was developed alongside community design centers, which provided local-level technical assistance to the communities on a number of issues, such as design and planning. The discussion about community design started in earnest from the early 1980s. A review of the literature m community design reveals several characteristics. First, community design deals with the relationship between the physical environment and several aspects of a region, including the social and cultural. Second, it involves community participation, which many scholars believe is the core of community design. Specifically, community design has been characterized by increased participation and democratic debate and decision making. The Third is about communication methods. Since the 1960s, diverse methods had been developed to promote communication effectively. Finally, community design must consider the relationship between designers, who typically value aesthetics and efficiency of form, and the needs of the community with which they are working. Indeed, some scholars believe that this relationship is generally contentious, although the designer can also be thought of as the facilitator of the community's needs. As community design practice becomes more prevalent, a review of the foundation of institution and policy and the role of experts is also needed. The community design movement bas been theorized ex post facto through diverse discussion that has sought to ascribe meaning and direction to its practice. In other words, the relationship between this theory and practice is cyclical. Therefore, this study can contribute to the virtuous circle.

• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.5
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• pp.113-121
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• 2010

Shumi-sen(須彌山), built by Nohjagong(路子工) in the southern garden of the Palace Garden during the Asuka Period, is understood as being Sumeru based on an Indian perspective of the theory of the origin of universe. It is also viewed as Mt. Myogoh from a Chinese Buddhist worldview. It is thought to be a type of assembled stone structure with Poong-ryoon (風輪)-Su-ryoon(水輪)-Geum-ryoon(金輪)-Ji-ryoon(地輪) carved into each of the 4 stone pieces. These building shapes are thought to have been utilized as stone for exterior construction as opposed to those structures built during the Shilla Period of China and Korea. Aside from Nohjagong's record of Shumi-sen, most of the records from Japan's period of the time suggest that Shumi-sen was an important element that played a role in the scenery of the seasonal outdoor gardens. It is also thought, from the sentences and expressions surrounding the records, that a combination of the seasonal sceneries was utilized centered on Shumi-sen, and that they were all used during festival events. From a perspective of analysis and interpretation dependent on the limited literature and on observation, it cannot be verified whether the Mt. Sumeru Stone(須彌山石) excavated from the Stone God Ruins is the same Shumi-sen that Nohjagong built along with Okyo(吳橋), but it is thought that the 'Shumi-sen type stone structure' that was later built repeatedly as part of the palace garden facilities is identical to the Shumi-sen built at the Imperial Palace's southern garden, or at least a re-built structure based on the Shumi-sen that Nohjagong built with stones and ponds used to create the foundation. Thus, Shumi-sen that Nohjagong supposedly built along with Okyo is suspected to be a figurative rock arrangement and, at the same time, a miniaturized scenic rock arrangement(縮景樹石) that maximized the shape of Buddhism's Shumi-sen. On the other hand, the surface pattern on Mt. Sumeru Stone is very similar to the multi -layers of mountainous pattern icons expressed in the patterns of the Great Golden Incense Burner(百濟金銅大香爐) or Mountain-Water Scenery Sculptural Brick(山水山景紋?) that were built during the Baekjae pcriod aod the rear side of Hwalsuk-jebul Basal Byungipsang(滑石諸佛菩薩竝立像); it is suspected that similar patterns would have been used if patterns were made on Shumi-sen that Nohjagong built. Also in consideration of the physical theory of MI. Sumeru Stone, the Siphon theory of using a pressure difference in water level was applied to the fountain facilities of Mt. Sumeru Stone that seemed to have been built from the practical rock arrangement perspective for the purpose of feasts, etc.