• Journal of Preventive Medicine and Public Health
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• v.5 no.1
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• pp.115-123
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• 1972

As a link of chain study program of school health, a survey was made up by the screening test with audiometry for hearing disturbance on 18,675 high school students who are mainly aged in 15-19 years from November 5.1969 to October 30. 1970. The results obtained were summerized as follows. According to our criteria as table 3, the rates of the profound, the severe and the moderate who required the appropriate hearing aids were 0.02%, 0.03% and 0.14% respectively:-the cumulative percentage was 0.197. When the marginal, 0.23% should be included the cumulative rate was 0.41%. But there was no-significance by sex and school classes. If we will make the special classes for them one class would be estimated out of 10,000 persons when a class is formed with about 15 persons. Otherwise when we examined that according to each ear of persons, the rates of the profound, the severe and the moderate were 0.17%, 0.22% and 0.33% respectively and their cumulative percentage wag 0.72. There was no significance also by sex and age. By the way, the rate of hearing disturbance in urban high school students tended to lower than rural. And the perceptive disturbance was higher than rural in rate. The conductive disturbance tended to oppose in comparison with the above.

• Journal of the Korea Computer Graphics Society
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• v.16 no.1
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• pp.21-27
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• 2010

Today the lectures are usually practiced in a teacher-led traditional classroom system or a student-led e-learning system. Students passively follow the teacher's lectures in both systems, though. Also due to the advances in 3D Computer Graphics and Game technologies, there are trials to exploit the positive effect of games in learning. The serious games, specifically designed games for an educational goal, or existing games for a special class have been used as lectures. Still these games have a great difficulty in being integrated into the educational system technically and economically. Therefore a new 3D MMORPG based lecturing system is presented in this paper. In our new lecturing system, the characteristics of a 3D MMORPG, achievement, sociality, and immersion, are provided to motivate students to participate actively in a lecture. A teacher and students interact with each other in realtime as 3D characters in a 3D virtual classroom on-line. An ordinary teacher can also easily apply our new system to existing classes since a teacher only needs to specify a slide file to prepare a lecture. For the future work, a user study and the effect of our new lecturing system will be performed.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1617-1617
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• 2001

It is well known now that near infrared spectroscopy (NIRS) is a fast, no destructive, and inexpensive analytical technique that could be used to classify, identify, and authenticate a wide range of foods and food items. Therefore, the main aims of this study were to provide a new insight into the authentication of five strawberry (Fragaria x ananassa) varieties and to correlate them with geographical zones and the propagating methods used. Three weeks plants of five different strawberry varieties (F. x ananassa Duch. cv Camarosa, Seascape, Chandler, F. Chiloensis, and F. Virginiana) were cultivated in vitro first and then transferred to pots with special soil, and grown in a greenhouse at CINVESTAV, all varieties were acquired from California (USA). After 18 months, ten leaves from each variety were collected. Transmission spectra from each leave were recorded over a range of 10, 000-4, 000 cm$-^{1}$, 32 scans of each strawberry leave were collected using a resolution of 4 cm$-^{1}$ with a Paragon IdentiCheck FT-NIR System Spectrometer. Triplicates of each strawberry leave were used. All spectra were analyzed using principal component analysis (PCA) and soft independent modeling class analogy (SIMCA). The optimum number of components to be used in the regression was automatically determined by the software. Camarosa was the only variety grown from the same shoot but propagated by a different method (direct or in vitro). Five different classes (varieties) or clusters were observed among samples, however, larger inter class distances were presented by the two wildtype samples (F. Chiloensis and F. Virginiana). Camarosa direct and Camarosa in vitro displayed a small overlapping region between them. On the other hand, Seascape variety presented the smallest rejection percentage among all varieties (more similarities with the rest of the samples). Therefore, it can be concluded that the application of NIRS technique allowed the authentication of all strawberry varieties and geographical origin as well. It was also possible to form subclasses of the same materials. The results presented here demonstrate that NIRS is a very powerful and promising analytical tool since all materials were authenticated and classified based on their variety, origin, and treatment. This is of a tremendous relevance since the variety and origin of a plant material can be established even before it gives its typical fruit or flower.

• 한국정보교육학회:학술대회논문집
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• 2010.08a
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• pp.15-18
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• 2010

As robots are proved to be effective in enhancing students' creativity and problem-solving abilities and satisfying various needs in special education for the gifted, many students participate in private education and after-school robot classes. However, it is difficult for students in the lower social economy class to use robots for their learning because of the high expense of robots. On this point, as a part of u-Learnng project, this research attempts to provide students in the lower social economy class with the opportunities to use robots for one year. At the end of the year, we will compare the experimental group and the control group in order to examine learning effects of using robots. Until now we have found many cases that show positive effects of the use of robots in students' learning.

• Korean Journal of Agricultural and Forest Meteorology
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• v.7 no.3
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• pp.211-219
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• 2005

Vegetation composition and structure of Sorbus commixta - native forests of South Korea were studied using phytosociological procedures and its ecological characteristics analyzed with special respect to species correlations, importance values, and constancy classes. Vegetation types were divided (great division) into Tripterygium regelii - Quercus mongolica (Inland high mountain type) and Acer takesimense - Fague crenata var. multinervis (Ulleung Island type) and ten accompanying vegetation units. In between S. commixta and life-farms, 120 correlations were positive with 23 of these having a p-value < 0.01 for trees, 21 for shrubs, 10 for woody vines, and 25 for herbs. In trees, there was a positive correlation between S. commixta and A. takesimense and T. insularis on the $1\%$ level. In shrubs, there was a positive correlation between S. commixta and Sasa kurilensis, Callicarpa japonica, Ligustrum foliosum on the $5\%$ level. In woody vines, there was a negative correlation between S. commixta and Tripterygium regelii and Actinidia rufa on the $1\%$ level. In herbs, there was a positive correlation between S. commixta and Majanthemim dilatatum and Solidago virga-aurea var. gigantea on the $1\%$ level.

• Journal of Science Education
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• v.34 no.2
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• pp.396-404
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• 2010

This study aimed to investigate a perception of teachers engaged in special education for scientifically gifted regarding nature of science and identify attitudes toward teaching nature of science. The sample of this study consists of 122 science teachers who are teaching or taught students attending gifted classes of any primary school in Korea and any gifted education center of every District Office of Education. We made a partial amendment of a VOSE that was developed by Chen(2006) and then used. We tested their perception and attitudes in regard to nature of science. In terms of nature of science, we devide it into 7 sub-areas to analyse. For attitudes toward teaching nature of science, we investigate and analyse following 5 sub-areas; tentativeness of scientific knowledge, nature of observation, scientific methods, theories and laws and subjectivity and objectivity. The result showed that the generally teachers have a desirable recognitions about a nature of science. For attitudes toward teaching nature of science, the teachers showed that they have positive attitudes. However between degrees of teachers' recognition about a nature of science and attitudes toward teaching nature of science showed a low correlation. To increase their understanding of nature of science and develop attitudes toward teaching nature of science, there should be more training time for the teachers and training contents also should be changed. In addition, we hope that this study contribute to develop contents and direction of training for the teachers as a basic reference.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.12
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• pp.1883-1896
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• 2009

This paper explores the use of Korean wrapping cloths (bojagi) in the late Joseon period and the types of decorations applied to them. Korean wrapping cloths called bojagi are pieces of cloths used by households of all social classes for practical purposes such as wrapping presents and covering food. In addition to the basic purposes, the making of bojagi was also an activity to express the down-to-earth wishes and the satisfaction of creation by the designer. With regard to the decorative feature of Korean wrapping cloths, five types of, patchwork, embroidered, painted, printed, and oiled-paper wrapping cloths, were examined. The patchwork wrapping cloths (jogakbo) show the frugality of Joseon women in addition to the well-developed composition skill of lines and colors. The embroidered wrapping cloths were prepared for special rituals and ceremonies such as weddings. Painted wrapping cloths were decorated with a Chinese-colors technique (called dangchae) or sometimes with black ink painting. For printed wrapping cloths, various sizes of woodblock printings and roller printings were used. Although monotone black ink was the main color applied to the printing, there was also wrapping cloths made from chintz having brilliant fast colors. Oiled-paper wrapping cloths called sikjibo were in use only for covering food. Cut-out work was employed to decorate it.

• The Korean Journal of Mycology
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• v.12 no.1
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• pp.15-19
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• 1984

Some factors affecting mycelial growth of Pleurotus sajor-caju and P. ostreatus. were investigated. The optimal temperature and pH of the medium for mycelial growth of both the species were $25^{\circ}C$ to $30^{\circ}C$, and 5 to 6, respectively. The effect of carbon and nitrogen sources on mycelial growth of the species was studied using modified Waksman's special medium as the basal medium. Generally, the disaccharides and polysaccharides showed good effect for mycelial growth of P. sajor-caju, and the polysaccharides were superior to the other classes of carbon sources for mycelial growth of P. ostreatus. Generally the organic nitrogen compounds showed good mycelial growth of both the species. The mycelial growth of the species were favored by the ammonium nitrogen more than by the nitrate nitrogen source. Asparagine was superior to the other kinds of amino acid. Six percentage of glucose and 0.6% ammonium tartarate was optimum for mycelial growth of P. sajor-caju whereas the optimum concentration for the P. ostreatut was 4% glucose and 0.4% ammonium tatarate.

• Proceedings of the KWS Conference
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• 2002.10a
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• pp.235-243
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• 2002

Ni-base superalloys are used extensively in industry, both in aeroengines and land based turbines. About 60% by weight of most modern gas turbine engine structural components are made of Ni-base superalloys. To satisfy practical demands, the efficiency of gas turbine engines has been steadily and systematically increased by design modifications to handle higher turbine inlet or firing temperatures. However, the increase in operating temperatures has lead to a decrease in the life of components and increase in costs of replacement. Moreover, around 80% of the large frame size industrial/utility gas turbines operating in the world today were installed in the mid-sixties to early seventies and are now 25 to 30 years old. Consequently, there are greater opportunities now to repair and refurbish the older models. Basically, there are two major factors influencing the weldability of the cast alloys: strain-age cracking and liquation cracking. Susceptibility to strain-age cracking is due to the total Ti plus AI content of the alloy; Liquation cracking is due either to the presence of low melting constituents or constitutional liquation of constituents. Though Rene 41 superalloy has 4.5wt.% total Ti and Al content and falls just below the safe limit proposed by Prager et al., controlled grain size and special heat treatments are needed to obtain crack-free welds. Varying heat treatments and filler materials were used in a laboratory study, then the actual welding of service parts was carried out to verity the possibility of crack-tree weld of components fabricated from Rene 41 superalloy. The microstructural observations indicated that there were two kinds of carbides in the FCC matrix. MC carbides were located along the grain boundaries, while M$_{23}$C$_{6}$ carbide was located both inter and intra granularly. Two kinds of filler materials, Rene 41 and Hastelloy X were used to gas tungsten arc weld a patch into the sheet metal, along with varying pre-weld heat treatments. The microstructure, hardness and tensile tests were determined. The service distressed parts were categorized into three classes: with large cracks, with medium cracks and with small or no visible cracks. No significant difference in microstructure among the specimens was observed. Specimens were cut from the corner and the straight edge of the patch repair, away from the corner. The only cracks present were found to be associated with inadequate surface preparation to remove oxidation. Guidelines for oxide removal and the welding procedures developed in the research enabled crack-free welds to be produced.d.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.18
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• pp.7645-7652
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• 2014

Neuroblastoma (NB), the most common extracranial solid tumor, accounts for 10% of childhood cancer. To date, scientists have gained quite a lot of knowledge about microRNAs (miRNAs) and their genes in NB. Discovering inner regulation networks, however, still presents problems. Our study was focused on determining differentially-expressed miRNAs, their target genes and transcription factors (TFs) which exert profound influence on the pathogenesis of NB. Here we constructed three regulatory networks: differentially-expressed, related and global. We compared and analyzed the differences between the three networks to distinguish key pathways and significant nodes. Certain pathways demonstrated specific features. The differentially-expressed network consists of already identified differentially-expressed genes, miRNAs and their host genes. With this network, we can clearly see how pathways of differentially expressed genes, differentially expressed miRNAs and TFs affect on the progression of NB. MYCN, for example, which is a mutated gene of NB, is targeted by hsa-miR-29a and hsa-miR-34a, and regulates another eight differentially-expressed miRNAs that target genes VEGFA, BCL2, REL2 and so on. Further related genes and miRNAs were obtained to construct the related network and it was observed that a miRNA and its target gene exhibit special features. Hsa-miR-34a, for example, targets gene MYC, which regulates hsa-miR-34a in turn. This forms a self-adaption association. TFs like MYC and PTEN having six types of adjacent nodes and other classes of TFs investigated really can help to demonstrate that TFs affect pathways through expressions of significant miRNAs involved in the pathogenesis of NB. The present study providing comprehensive data partially reveals the mechanism of NB and should facilitate future studies to gain more significant and related data results for NB.