• Communications of Mathematical Education
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• v.25 no.2
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• pp.403-430
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• 2011

The purpose of the study was to investigate how the use of graphing calculators influence on forming students' mathematical concept of algebra, students' mathematical connection, and attitude toward mathematics. First, graphing calculators give instant feedback to students as they make students compare their written answers with the results, which helps students learn equations and linear inequalities for themselves. In respect of quadratic inequalities they help students to correct wrong concepts and understand fundamental concepts, and with regard to functions students can draw graphs more easily using graphing calculators, which means that the difficulty of drawing graphs can not be hindrance to student's learning functions. Moreover students could understand functions intuitively by using graphing calculators and explored math problems volunteerly. As a result, students were able to perceive faster the concepts of functions that they considered difficult and remain the concepts in their mind for a long time. Second, most of students could not think of connection among equations, equalities and functions. However, they could understand the connection among equations, equalities and functions more easily. Additionally students could focus on changing the real life into the algebraic expression by modeling without the fear of calculating, which made students relieve the burden of calculating and realize the usefulness of mathematics through the experience of solving the real-life problems. Third, we identified the change of six students' attitude through preliminary and an ex post facto attitude test. Five of six students came to have positive attitude toward mathematics, but only one student came to have negative attitude. However, all of the students showed positive attitude toward using graphing calculators in math class. That's because they could have more interest in mathematics by the strengthened and visualization of graphing calculators which helped them understand difficult algebraic concepts, which gave them a sense of achievement. Also, students could relieve the burden of calculating and have confidence. In a conclusion, using graphing calculators in algebra and function class has many advantages : formulating mathematics concepts, mathematical connection, and enhancing positive attitude toward mathematics. Therefore we need more research of the effect of using calculators, practical classroom materials, instruction models and assessment tools for graphing calculators. Lastly We need to make the classroom environment more adequate for using graphing calculators in math classes.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.16 no.4
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• pp.314-323
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• 2006

This study was conducted to identify ingredients of thinners and to confirm reliability of material safety data sheets (MSDS) of thinners for public and workers' health. The 41 thinner products were collected from paint shops located in Busan and Gyeongnam province. The 12 thinner products among them were identified using product MSDS. GC-MSD was used to analyze 41 kinds of thinners qualitatively and quantitatively. The 12 products MSDS were compared with thinner's component through qualitative analysis to confirm MSDS. Chemical ingredients, such as Benzene, Toluene, and Xylene etc., of thinners were analysed in quantity. The 41 thinner products contained 17 disclosed specific, trade name, or generically described chemical solvent ingredients. These 17 ingredients came under 6 classes: alcohols, aromatic hydrocarbons, esters, glycol ethers, ketones, and mixtures. These 17 ingredients were important in the view of industrial hygiene and had occupational exposure limit in the ambient, such as toluene, xylene, acetone, nonane, EGEE, heptane, cumene, MIBK, indene, tri-methyl benzene, etc, were found in 41 kinds of thinners. Aromatic hydrocarbons were the most identified ingredient in thinners. Especially, the benzene, which induces leukemia, was found in 4 kinds of thinners. The content rates of benzene in thinners were 0.25~1.18%. The benzene in enamel thinner, which were 0.39~0.72%, was highest from chemical classification. The contents of toluene, which was found from 27 kinds of thinners, were 5.35~64.16%, which were highest in sobu thinner as 58.80%. Xylene was found from 22 kinds of thinners and contents of xylene were 4.61~72.42%. Acrylic thinner's contents of xylene were 12.06~51.05%, which was most high. It was found that contents of benzene were increased and frequency of detection was decreased through comparison with other study. The MSDS possession rate of paint shops was low as 29.27%. So it did not provide information with public or workers. Mean of agreement rate between MSDS and components of thinners through qualitative analysis was 42.01% and it has wide range from 8.3% to 75%. There are many deficiencies in MSDS about component of thinners. In some case of sample, expecially, despite containing benzene, information was not written it on MSDS.

• Journal of Sericultural and Entomological Science
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• v.7
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• pp.1-26
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• 1967

In order to develop the standards for the measurement of drought resistance in mulberry trees (Morus genus) the varietal differences of drought resistance were measured for 30 mulberry varieties, and the relationships between the drought resistance and the histological and physiological characteristics of mulberry leaves were investigated. The results were summarized as follows; 1. It is reasonable to use the drought resistance ratio, expressed by D/D'＊100, for the standard of drought resistance measurement for mulberry tree as a perennial tree crop. Where: D stands for growth amount(shoot length) in the plot of dry treatment, at the end of treatment. D' stands for an expected value of D which is expressed by B＊C/A. Here, A is the growth amount of wet treatment plot at the beginning of treatment, B is the growth amount of dry treatment plot at the beginning of treatment, and C is the growth amount of wet treatment plot at the end of treatment. 2. The results obtained from the application of above formula showed that the varieties Cadaneo, Tahozosaeng, Yongchunchuwu, Kaeryang suban. and Kabsun were highly resistant to drought and the varieties Jukmok, Shipyung, Sobun, Kaeryangzosaeng shipmoonza and Chungagokyo were highly susceptible. 3. Among leaf tissues. the rate of inter-cellular space showed the highest relationship with drought resistance. The correlation coefficient calculated (r=0.4153) was highly significant. Other leaf tissues such as epidermis and palisade showed no significant correlations with drought resistance. 4. The size and density of stomata were correlated to drought resistance. That is: Correlation between drought resistance and size of stomata(length ${\times}$ width)......r= -0. 3253(signif. at 5%) density(No. of stomata/l$\textrm{mm}^2$......r= +0.5047(signif. at 1%)

• Journal of Korean Ophthalmic Optics Society
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• v.12 no.3
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• pp.83-87
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• 2007

This study was classified and compared astigmatism's refractional abnormal degrees with visual acuity state of full correction which turned on axises of only 5 degree, 10 degree, and 15 degree. Subjects of this study were 57 college students (114 eyes) who had neither eye diseases nor binocular abnormality, were from their twenties to fifties, with myopia. It appeared that 30.8% of subjects who had astigmatism wore glasses with wrong axis of astigmatism. After accurate correction of the visual acuity and degrees of astigmatism, when we moved to corrected axises at 5 degree, 10 degree, 15 degree, failure of visual acuity with one line or more were 56.1%, 84.2%, 93.8%, respectively. When we comapre the completely-corrected visual acuity with the visual acuity with dricted axes, the bigger the width of visual acuity's weakness was the bigger the drifted angle. The change of normal visual acuity according to drifting angle of corrected axises of astigmatism, when we compared with full correction, appeared 0.94 in 5 degree, 0.87 in 10 degree, and 0.79 in 15 degree. Drift of 5 degree from fully corrected axis, corresponded to difference of visual acuity about one line, drift of 10 degree to 1.8 line difference of visual acuity, and drift of 15 degree about to 2.6 line difference. Through this study, we were sure that, in the case of drifting away from the right axis of astigmatism, it lead to visual weakness and asthenopia. Therefore we darely advise that optometrists should make mistake of axis least by confirming accucacy of corrected axis after despensing of spectacles of astigmatism.

• Journal of The Korean Association For Science Education
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• v.19 no.3
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• pp.428-440
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• 1999

The colorful overhead projector films, named as Bio-cosmos II, including photographs, pictures, concept maps, and diagrams, were developed and manufactured as audio-visual teaching aids and teaching resources for students' biology learning in high school, and the CD-ROM and web sites for their application to the school were also constructed. The content of the films was organized based upon the analysis of seven different biology textbooks approved by the Ministry of Education. The films were designated based on various instructional strategies and manufactured using multimedia with various educational softwares. The CD-ROM was composed of the scenes as logo, initial main, chapters list, contents, and quit. Initial main scene indicated various chapters according to the texts of biology areas in General Science, Biology I, and II. Each chapters linked with the scenes for detailed concept maps, the downstream real subjects, and contents. The subject screens were composed of various types of summarized diagrams including lesson contents, figures, pictures, photographs, and their explanation, experimental procedures and results, tables for summarized contents, and additional animation with video captures, explanations, glossary, etc. Most files were manufactured in software Adobe Photoshop by scanning the pictures, figures and photographs, and then the explanation, modification, storing with PICT or PSD files, and transformation with JPG files, were processed in the aspect of high quality in terms of instructional strategies and graphic skills on gracefulness, clearness, colorfulness, brightness, and distinctness. A 14 films for biology areas in General Science, 80 for Biology I, and 142 for Biology II were manufactured and loaded to the CD-ROM and web site, and the files had been attempted to opened with an internet home-page of http://gic.kyungpook.ac.kr/biocosmos.

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.6
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• pp.81-90
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• 2009

This study seeks those elements that form a sense of place in Yen-Ben Street, which represents a typical ethnic enclave in Seoul, to provide a basic resource in the creation of an urban landscape that can provide a positive space for cultural diversity. The results of the study can be summarized as follows: First, the element of a physical environment that develops a sense of place was in fact the poor dwellings that correspond to the economic condition of Korean Chinese. While this element has a negative cognition to outsiders, Korean Chinese feel positively toward it. Secondly, signboards were a physical element of sense of place which retains cultural identity as a means of communication inside the community. Thirdly, it was found that activities such as shopping, recreation, and the exchange of information that are found in the pursuit of daily life act as an essential element in the formation of a sense of place even more than architectural elements. Fourthly, the appropriation of space by Korean Chinese and the isolation from the surroundings were obvious. This isolation is perceived as a negative sense of place formation to outsiders in Yen-Ben Street. Fifthly, the aspects of cultural dualism, mingling the concepts of home country, language, writing, and food have also affected the formation of a sense of place in the area. Sixthly, transience was a prominent phenomenon of Yen-Ben Street and is strengthened by illegal immigration. Although transience causes negative impacts such as in a lack of concern for the residential environment, it acts as a positive factor in the sense of place by mitigating uneasiness, and strengthening insider ties and cooperation.

• Journal of Science of Art and Design
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• v.8
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• pp.161-184
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• 2005

Traditionally, Korean ink painting used paper as a background medium. This tradition has sought a new attempt to meet today's demands while its expressive techniques and mediums become more diverse. The attempt of Korean ink painting to explore new mediums could change both its structure and style when considering the significance of the medium in the work. These new attempts have encouraged a further study of 'Korean Traditional Paper'. Today, 'Korean Traditional Paper' is considered to be an object itself rather than just being a background. In other words, there is no implication of a separation between the medium 'Korean Traditional Paper' and the work. Instead, the medium itself becomes the work. Therefore, 'Korean Traditional Paper' is not only a 'background' that contains the artist's desire to express, but at the same time also an 'object'. This study focuses on the attributes of 'Korean Traditional Paper' as an object, examines how this is visually applied in contemporary Korean ink painting in the relation to 'Korean Beauty', and reviews the work of some artists that use Korean Traditional Paper. The use of Korean Traditional Paper as an object first began with the experimental techniques of Lee , Eung-Noh and Kwon, Young-Woo in the 1960s, Then it seemed to stop for a while in the 1970s and 1980s until there was a renewed interest in the material personality of Korean Traditional Paper with the birth of the 'Korean Traditional Paper Artists Association' in the 1990s. This interest increased and Korean Traditional Paper was earnestly adopted by artists like Yim, Hyo Lee, Ki-Sook Won, Moon-Ja and Choi, Moo-Young, who used the paper in Broussonetia, the previous fibered state of rice paper. Here, the expression of the object through the characteristics of Korean Traditional Paper is a visual experiment to discover Korea's traditional art mediums that were forgotten once, focusing on the manifestation of Korean Beauty through Korean Traditional Paper. In this respect, this attempt has a valuable meaning in its use with a contemporary visual sense , based on the Korean sense of beauty.

• Archives of design research
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• v.12 no.1
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• pp.145-154
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• 1999

With the introduction of digital technology since the late 1970s, we have been shifting from the industrial era into the information age. New communication systems have changed our concept of reality. Korea has a wealthy communication heritage with its own language and alphabet. However, Korean typography today has struggled to keep its originality, and does not hold up well to international standards. Korean contemporary typography is not efficient for communicating. It is not orderly, organised and simple. It has currently become complicated and decorative. Moreover, many young designers are attracted by imitations of western trends. It is now time for Korea to reveal its own identity. How can it develop a new typographic language that is more sympathetic to Korean tradition\ulcorner How will Korean information design produce a contemporary style with international relevance that contributes to world culture\ulcorner This thesis will be developed a new Korean typographic language that relies more on Korean traditions. Simultaneously, in this thesis will be examined Swiss typography as a relevant style for a new Korean typography to incorporate. Swiss typography maintained a similar philosophy to Korean tradition with its emphasis on clarity and simplicity. This study will be explored the potential of creating a contemporary Korean typographic solution which combines the traditions of Korea with the clarity of Swiss typography. The first attitude of the new typographic language should focus on legibility. The second condition of the new typographic philosophy based on the ability of designers is interpretation of context. The third concept of the new language is founded on an objective, rational design attitude. The final mental attitude of the new typographic language should feel a deep obligation to traditions. It is crucial time for Korean alphabet to establish a relevant standard rather than goes uncritically with the international current. Korea has had worthy traditions. It is suggested that the answers to 'good design' lie in the study of Korea's own history. Simultaneously, the research of Swiss design which is a

• Journal of Korean Ophthalmic Optics Society
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• v.20 no.2
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• pp.177-186
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• 2015

Purpose: The Purpose of this study is to investigate if the relative legibility of optotypes affects the corrected visual acuity in visual acuity test. Methods: After measuring the relative legibility of 'Landolt ring target', 'arabic number target', 'alphabet target' by showing as a single-letter-target in 24 subjects without specific ocular diseases and ocular surgery experience, the relative legibility of 0.8, 1.0, 1.25 row of vision according to type of target in 7 types of chart were compared. After then we compared by measuring the corrected visual acuity according to type of target by using binocular MPMVA test (#7A) in 60 myopic subjects. Results: In 3 types of target the worst relative legibility target was 'Landolt ring target' with legible distance of $98.97{\pm}4.57cm$ and the best relative legibility target was 'alphabet target' with legible distance of $108.42{\pm}3.46cm$. There was no difference of the relative legibility according to type of chart or visual acuity level in the row of vision if other conditions are the same. In 1.0 and 1.25 row of vision the difference of relative legibility according to type of target was shown the statistically significant difference between 'Landolt ring target' and 'alphabet target' as $-0.07{\pm}0.06$ (p=0.02) and $-0.06{\pm}0.06$ (p=0.04) respectively. In myopia the difference of corrected visual acuity according to type of target was statistically significant difference between 'Landolt ring target' and 'arabic number target' as $-0.04{\pm}0.02$ (p=0.02) and it was especially remarkable in the low myopia. Conclusions: Measuring visual acuity with different optotypes could cause the errors in best vision measurement value because there was difference of the relative legibility according to type of target even though visual acuity level is same in the row of vision.

• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.1
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• pp.98-106
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• 2010

Bangseonmun(訪仙門) is the attractive spots where Shinseon(神仙: Taoist hermit) ideas that makes Mt. Younju(瀛洲山) or the current Mt. Halla mystique has still remained and situated at Hancheon(漢川) Valley. Bangseonmun, which is known as 'Landscape Setting Here($L_{SH}$)' of Youngguchunhwa(瀛丘春花), which is one of ten famous spots in Youngjusipkyung(瀛洲十景), and Deulreonggui refer to 'the gate to the place where Shinseon is living.' It is described as the path to Mt. Youngju for Shinseon and the boundary between the mundane world and the world beyond the mundane. The old scholars at Mt. Halla entered the gate and met Shinseon, carving the word or picture of Bangseonmun, Whanseonmun, Wuseondae or Deungyounggu so as to structure the enchanting image on Bangseonmun. It is the poetic expression of the taste for the arts, breaking from the troublesome mundane world and riding the white deer to become the Shinseon, the desire for the ideal world in Taoism, and the identity of four famous scenic spots of Bangseonmun. Besides its enchanting meaning and the locational value of Bangseonmun, geological features of the valley and river and ecological value prove its unique value as a natural scenic beauty. Not to mention the locational identity and enchanting meaning of the poets carved in Meeaegak of Bangseonmun and the scenic view of 'Youngguchunhwa' as the subject of 10 famous scenes of Youngju, it is the place for communing with nature with the natural beauty of Bangseonmun Valley. As the cultural place for being together with Jeju people, it simultaneously shows the typical model as a scenic spot in our living. Viewing the scenic value and standard from the aspect of the Cultural Properties Protection Law, Bangseonmun Valley in Jeju must be the typical place and space that meet the requirements to become scenic sites.