• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.2
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• pp.324-334
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• 2017

The simulators for a plant unit master control (UMC) developed by domestic or overseas researchers have been developed for operator-training purposes. UMC simulators normally constructed at the end of the plant construction, despite the UMC logics, should be simulated to pre-check many signal interfaces within the power generation systems. Because of the differences in construction schedule, it is difficult for logic designers or commissioning engineers to simulate the UMC logic during the design or commissioning stage. In this background, this paper proposes a simulation method that can be used easily by plant logic designers or operators in the MATLAB Simulink programming environment. The core of the UMC is realized with a unique simulation algorithm based on mathematical analysis and functional blocks combination. In addition, an integer-based configuration was proposed to realize the plant target value control for the equipment in the logic. With these simulation methods, functions, e.g., load distribution, high-low limitations, frequency compensation, etc. were simulated. The results showed that the plant UMC logic can be simulated in Simulink without a plant simulator. The various functions proposed in this paper can provide useful information about Simulink-based simulation design for plant logic designers or commissioning engineers during the power plant construction period.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.2
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• pp.230-235
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• 2020

Objective: This study was realized to evaluate the nutritional value of rice grains as a replacement for corn grains in the diet of growing Hanwoo steers. Methods: Two experimental diets were prepared: i) Corn total mixed ration (TMR) consisting of 20% corn grains and ii) Rice TMR consisting of 20% rice grains, in a dry matter (DM) basis. These treatments were used for in vitro rumen fermentation and in vivo growth trials. In the rumen fermentation experiment, the in vitro DM digestibility (IVDMD), in vitro crude protein digestibility (IVCPD), in vitro neutral detergent fiber digestibility, pH, ammonia nitrogen, and volatile fatty acids (VFA) were estimated at 48 h, and the gas production was measured at 3, 6, 12, 24, and 48 h. Twenty four growing Hanwoo steers (9 months old; body weight [BW]: 259±13 kg) were randomly divided into two treatment groups and the BW, dry matter intake (DMI), average daily gain (ADG), and feed conversion ratio (FCR) were measured. Results: The in vitro experiment showed that the IVDMD, IVCPD, and VFA production of the Rice TMR were higher than those of the Corn TMR (p<0.05). The growth trial showed no differences (p>0.05) in the final BW, ADG, DMI, and FCR between the two TMRs. Conclusion: The use of rice grains instead of corn grains did not exhibit any negative effects on the rumen fermentation or growth performance, thereby rice grains with a DM of less than 20% could be used as a starch source in the diet of growing steers.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.23 no.3
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• pp.135-141
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• 2013

Mechanical alloying was carried out to produce $CrSi_2$ thermoelectric compound using a mixture of elemental $Cr_{33}Si_{67}$ powders. An optimal milling and heat treatment conditions to obtain the single phase of $CrSi_2$ compound with fine microstructure were investigated by X-ray diffraction and differential scanning calorimetry measurement. $CrSi_2$ intermetallic compound with a grain size of 70 nm could be obtained by MA of $Cr_{33}Si_{67}$ powders for 70 hours and subsequently annealed at $650^{\circ}C$. Consolidation of the MA powders was performed in a spark plasma sintering (SPS) machine using graphite dies at $600{\sim}1000^{\circ}C$ under 60 MPa. The shrinkage of MA samples during SPS consolidation process increased gradually with increasing temperature up to $1000^{\circ}C$ and relatively significant at about $600^{\circ}C$. We tend to believe that these behaviors are deeply related to form a $CrSi_2$ compound during heating process, as can be realized from the DSC measurement. Electrical conductivity and Seebeck coefficient of sintered bodies were measured up to $900^{\circ}C$. Seebeck coefficient and power factor of $Cr_{33}Si_{67}$ compact prepared by MA and SPS at $1000^{\circ}C$ showed the maximum value of $125{\mu}V/K$ at $400^{\circ}C$ and $4.3{\times}10^{-4}W/mK^2$ at $350^{\circ}C$, respectively.

• Journal of the korean academy of Pediatric Dentistry
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• v.47 no.3
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• pp.266-276
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• 2020

The purpose of this study was to compare the remineralization effect of 38% silver diamine fluoride (SDF) and 5% sodium fluoride (NaF) varnish on artificially induced enamel caries. The present study standardized the physiochemical characteristics of the tooth structure using bovine teeth, realized the wash-off action of agents using a saliva, reproduced an environment similar to mouth through pH-cycling, and comparatively assessed the remineralization effect of 38% SDF and 5% NaF varnish in a non-destructive method using micro-CT. And the remineralized enamel surface structure was analyzed by scanning electron microscopy (SEM) and energy dispersive X-Ray spectroscopy (EDS). In both SDF and NaF varnish, mineral density (△Hounsfield unit value) and the volume of enamel restored to normal mineral density through remineralization gradually increased with time. And the SDF showed a much higher level of increase in mineral density at all depths and remineralized volume than NaF varnish. According to SEM analysis, the surface roughness decreased in the order of artificial saliva, NaF varnish and SDF. In addition, EDS analysis showed that silver ion was precipitated on the enamel surface in SDF group. In conclusion, SDF had a greater remineralization effect than NaF varnish on demineralized enamel.

• Journal of Korean Home Economics Education Association
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• v.22 no.4
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• pp.155-183
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• 2010

The purpose of this study is to obtain a suggestion for writing, revising, and reorganizing for the current Korean Home Economics Textbook. To achieve this goal, the housing unit in the Home Economics curriculums from eight kinds of Japanese textbooks were analyzed. The subject of analysis was Technology Home Economics textbook Home Economics Part 2 volumes used in middle school 2009 and Home Economics Synthesis 6 volumes in high school. Contents of main text, terminology, reading material, tables and activities were analyzed. The suggestions of this analysis are as followings. First according to the increase of the level of school, if the field of housing is organized to be intensified systematically with relation to education, the goal of the subject would be clearly realized to the students. Thus, the middle school curriculum and textbook of housing field should be constructed with the consideration of education level according to the grade and the level of school. The method of intensive education in single point of time would result in low efficiency so the current curriculum should be re-considered. Second, perspective of resident, local community, terrain environment, housing culture should be included in housing education so that the learner may value the relationship between him and the society, think of the earth environment, succeed and advance the traditional culture. Third, the curriculum of the housing field should be organized with the consideration of understanding the level of middle, high school students. Middle school, with their student's low understanding, should include more experiential activity such as experiment and practice in their curriculum. On the other hand, curriculum which can enable student to research problems on their own and to apply them in their real life is required in high school course.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.4
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• pp.73-84
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• 2014

This research has conducted historical data analysis and on-site investigation on Chungam Pavilion and Seokchun Valley in Bonghwa. Based on the results, the original planting form was identified, and the vegetation management were drawn up. The results of this study can be summarized as follows. First of all, The Book of Seokchun states that there used to be forest trees such as pine tree, saw-leaf zelkova and maple tree, and flowering trees such as peony, royal azalea, rose, chrysanthemum, and lotus, planted around Chungamjeong. Around Seokchunjeongsa, there used to be boxwood, bamboo, maple, peach, gooseberry and peony planted in the area. Through this discovery it can be realized that the vicinity of Chungam Pavilion and Seokchunjeongsa provided not only the grand aesthetics of four clear seasons, but also planting landscapes with various symbolistic significance and meanings. The description of the planting situation in the historical records offers a useful reference for future vegetation management in Chungam Pavilion, Seokchunjeongsa and surrounding valleys. Furthermore, it holds critical value in the identification of planting pattern in late Chosun dynasty. Second, the planting landscape in and around Chungam Pavilion and Seokchunjeongsa will have to be maintained as described in the historical records The Book of Seokchun. Also, the once famous colony of pine trees in the area is gradually reducing in its scale, which calls for active management measures such as elimination of broadleaf trees.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.31 no.2
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• pp.82-91
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• 2013

This study was performed in order to analysis the landscape change and cause of scenic sites and surrounding environment is located in the Urban Residential Area since modern. The study was carried out using of field observations, literature review, cadaster map analysis from 1962 to 2010, and survey. It trace about Seongnagwon, Mapo Choi Sa-Young's old house, Seoul Seonjamdanji, Seoul Hanyang castle and those can be process of change per period. Also, it examine to original view of cultural assets and analysis about lots alteration with landscape alteration. Seongnagwon has original view which constructed the Songseokjeong and pond in 1954. Mapo Choi Sa-Young's old house has original view that move to Sungbook-dong and restore an old house. Seoul Seonjamdanji has it define original view that remained ruins by 1960's development. Seoul Hanyang castle has original view that stone fortress. Seongnagwon's landscape was changed by institutional factors. Mapo Choi Sa-Young house's landscape was changed by society economic factors. Seoul Seonjamdanji was changed by society economic and institutional factors. Seoul Hanyang castle was changed by technical and institutional factors. Generally cultural heritage of Sungbook-dong was changed by institutional and society economic factors. It is guessed that Seoul urban planning influenced Sungbook-dong development. The establishment of capitalistic economy system was backgrounds to it. Therefore, it expect to realized desirable landscape alteration that recognized potential value as culture resources.

• Cartoon and Animation Studies
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• s.49
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• pp.87-112
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• 2017

Overlap what images are laid on top of each other performs various purposes of artistic expressions. Especially, overlap to describe motion has been placed on lots of art fields analysing and connecting each part of motion. This kind of overlap is called as 'Locomotive overlap' and it is defined as 'Technique for multiplication to arrange simultaneously motions of single object on one screen'. Locomotive overlap was started from fine art and photography, so this static kind of it is classified as 'Static locomotive overlap'. Afterwards, film and animation succeeded static locomotion overlap and realized real dynamic locomotive overlap with moving images, so this dynamic kind of it is classified as 'Dynamic locomotive overlap'. Most of all, by Norman McLaren accomplished its own artistic value and aesthetics in locomotive overlap has been placed in the center of the history of locomotive overlap, so to analyze this work and to research before and after it will confirm context and artistic achievements of locomotive overlap. Nowdays locomotive overlap is extending its technology and dimension more and more on the strength of development of digital technology. Some of works using digital technology show new possibilities of locomotive overlap by reinterpreting original media and concept of . Ultimately, this research for locomotive overlap focusing on the analysis of confirms artistic achievements of locomotive overlap and suggests to contemplate the meaning and new possibilities of it.

• Sijohaknonchong
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• v.30
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• pp.9-20
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• 2009

The purpose of this study is to consider factors such as one's sight of viewing afar, expressional principles, and basic aesthetic category, which are treated importantly by the poets of the Joseon Dynasty era in appreciating nature. 'Afar' of the viewing afar is actual distance and aesthetic distance at the same time. Viewing afar is to find geographical features, depth, and details of a mountain, seeing the whole nature at a high place. Also, it can make possible escape from the external limitation of nature and get mental superiority and enhancement. Ultimately, viewing afar is to find out everlasting change of the nature and reason of natural creation. One's sight in viewing afar makes an appreciator's mind empty and calm, and it makes chance to harmonize human with nature. Viewing afar is to unite human nature to naturality beyond realistic value, idea, and artificiality. The mind from viewing afar has peacefulness and it is a state of serenity without any secular atmosphere. Viewing afar is an eye for beauty to leap toward an endless free state from narrow sight about objects. It rejects modification and technics in achieving an world of harmony. It means that objects should not be restrained by human's recognition. There are three expressions, which are high, horizontal, and transcendental viewing afar. The aesthetic category and beauty of peaceful mental state are realized by the expressions. The peaceful mental state makes peaceful mind from realistic conflicts and makes us experience a profound reason of nature.

• Atmosphere
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• v.16 no.2
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• pp.97-110
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• 2006

This study investigates the response of a typhoon model to the change of the sea surface temperature (SST) throughout the model integration. The SST change is parameterized as a formulae of which the magnitude is given as a function of not only the intensity and the size but the moving speed of tropical cyclone. The formulae is constructed by referring to many previous observational and numerical studies on the SST cooling with the passage of tropical cyclones. Since the parameterized cooling formulae is based on the mathematical expression, the resemblance between the prescribed SST cooling and the observed one during the period of the numerical experiment is not complete nor satisfactory. The agreements between the prescribed and the observed SST even over the swath of the typhoon passage differ from case to case. Numerical experiments are undertaken with and without prescribing the SST cooling. The results with the SST cooling do not show clear evidence in improving the track prediction compared to those of the without-experiments. SST cooling in the model shows its swath along the incomplete simulated track so that the magnitude and the distribution of the sea surface cooling does not resemble completely with the observed one. However, we have observed a little improvement in the intensity prediction in terms of the central pressure of the tropical cyclone in some cases. In case where the model without the SST treatment is not able to yield a correct prediction of the filling of the tropical cyclone especially in the decaying stage, the pulling effect given by the SST cooling alleviates the over-deepening of the model so that the central pressure approaches toward the observed value. However, the opposite case when the SST treatment makes the prediction worse may also be possible. In general when the sea surface temperature is reduced, the amount of the sensible and the latent heat from the ocean surface become also reduced, which results in the weakening of the storms comparing to the constant SST case. It turns out to be the case also in our experiments. The weakening is realized in the central pressure, maximum wind, horizontal temperature gradient, etc.