• Journal of Radiation Protection and Research
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• v.29 no.3
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• pp.165-172
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• 2004

Rice plants were exposed to $I_2$ vapor for 80 min at different growth stages in an exposure box to investigate the parameters concerning direct plant contamination. Deposition velocity $(m\;s^{-1})$ of the $I_2$ vapor for the straws was in the range of $1.4{\times}10^{-5}-1.3{\times}10^{-4}$ depending on the exposure time, being comparatively low during the earlier part of the plant growth. Ear deposition velocity was in the range of $2.5{\times}10^{-5}-6.7{\times}10^{-5}$. Whole-plant deposition velocity was in the range of $1.4{\times}10^{-5}-1.8{\times}10^{-4}$ with the highest from the exposure performed on Aug. 18 (7 d after the start of heading). The time-dependent variation generally decreased when the deposition velocity was normalized to the biomass density No noteworthy tendency in the deposition velocity was observed with regard to the temperature, sunlight and humidity. Translocation factor for the hulled seeds was $3.3{\times}10^{-5}-4.7{\times}10^{-4}$ with the highest from the Aug. 23 exposure. It was found that a leaf deposition even before the ear emergence resulted in a considerable seed translocation.

• Journal of The Korean Association For Science Education
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• v.35 no.1
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• pp.143-157
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• 2015

The purpose of this study is to examine the possibility of science education using Korean TSK(Traditional scientific knowledge). In this study, we have developed five Korean TSK units including science concepts, historical knowledge and cultural experience and applied them to 10th graders. The five units are as follows: (1) Calendars(western and eastern), (2) Our traditional sundial, Angbuilgu, (3) A great scientist in the King Sejong Era, (4) Data interpretation of ancient record of natural phenomenon in Korea, and (5) Gyeongbokgung Palace. The analyses included a pre- and post test of students' perception, classroom observation, students' activity sheets, and interview. The results show that the students' perception of Korean TSK has changed toward recognizing the value of Korean TSK as a kind of natural science. They expressed their expectation of Korean TSK in scientific, practical, and emotional perspectives, wherein some students thought the practical and emotional perspectives of Korean TSK as non-scientific characteristics. Students showed five types of worldview about the relationship between Korean TSK and WMS(western modern science). Most students favored and cherished the Korean TSK but at the same time, they were confused about its scientific value. The results support the rethinking of the meaning of science and what students learn in school. We should consider how we teach the Korean TSK to students. It is important that a profound research of the Korean TSK should be continued to make our science education varied.

• Journal of The Korean Association For Science Education
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• v.32 no.10
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• pp.1537-1550
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• 2012

This study aims to explore the differences between Korean and United States college students regarding their degree of religiosity, interest in, understanding and acceptance of evolution, and the effects of their interaction on these variables. A total of one thousand and fifteen Korean and US biology majors and non-majors college students participated in this study and a sub sample of 516 students were randomly selected for statistical tests. The results illustrated that Korean college students harbored significantly lower degrees of religiosity and interest in evolution but significantly higher degrees of knowledge and acceptance of evolution than US college students. The path analysis uncovered that the knowledge of and interest in evolution played a mediating role between religiosity and acceptance of evolution. Korean college students' interest in evolution was less correlated to other variables than US college students' interest. The acceptance of evolution was less predicted by knowledge of evolution in the Korean biology major sample than in the US biology major sample. The acceptance of evolution was predicted more by religiosity in the Korean non-major sample than in US non-major sample. This study suggests that future Korean science curriculum for evolution needs to enhance the degree of students' interest in evolution. In addition, future Korean science curriculum needs an instructional strategy in developing students' ability to make scientific decisions, such as the acceptance of evolution, without interference from their personal religious belief.

• Journal of The Korean Association For Science Education
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• v.32 no.10
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• pp.1524-1536
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• 2012

Science attitudes affect the quality of learning, and they are considered as one of the major concerns in science education. It is necessary to analyze the proximity between concepts with science attitudes. Accordingly, this study was designed to analyze the proximity of the concept related to photosynthesis as it changed after class according to the levels of science attitudes. A survey on the concept of photosynthesis and science attitudes before and after class was conducted on 270 7th-grade students. The concept of photosynthesis was composed of 'the place of photosynthesis,' 'products of photosynthesis,' 'reactants of photosynthesis,' and 'environmental factors.' The proximity of the concept of photosynthesis was analyzed through the utilization of multidimensional scaling (MDS). The research results were as follows: (1) Students changed the proximity between concepts by acquiring concrete concepts through class. (2) The upper group in science attitudes tends to be closer to the proximity between scientific concepts through class, compared to the intermediate and lower groups. (3) In all students with entire levels of science attitudes, non-scientific concepts continued to exist even after class, and the non-scientific concepts were deemed to interfere with the proximity between scientific concepts related to photosynthesis. (4) Students turned out to be aware of the concepts related to each other in four areas associated with photosynthesis. That is, it can be said that students are closely aware of the place where photosynthesis can occur and the materials needed as well as materials generated as a result of photosynthesis and the materials needed in terms of concepts related to photosynthesis.

• Journal of The Korean Association For Science Education
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• v.30 no.6
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• pp.752-769
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• 2010

The purpose of this study was to apply the microgenetic analysis method for development of information on an individual's change in a certain area during a consistent time period to seek change in scientific questions that elementary school students create. The study subjects were six 6th graders in I elementary school located in Kyunggido with the students conducting 6 sessions of two observational tasks about dry grapes contained in soda pop and candlelight. Information were collected through students' scientific question development paper, record of field observation and interviews. The results of this study are as follows: first, the number of scientific questions that the elementary school students developed showed a tendency for reduction; second, the changes in type of scientific questions bring different results, which depend on a particular characteristic of the tasks; third, By observing pattern changes in scientific questions of each individual, it was found that different results show for each time for the same task, which in other words means that there exists variability within an individual. Also, variability between individuals were shown by confirming that the change pattern for each person were diverse. Thus, the result of this study shows the following implications on education of scientific question development. For students, scientific question development mean more opportunities to increase the process of developing and acquiring knowledge. Therefore, it is important to create situations where one can come up with scientific questions. In addition, analysis in tasks' nature when selecting tasks would be necessary to develop diverse scientific questions.

• Culinary science and hospitality research
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• v.16 no.4
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• pp.28-42
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• 2010

The purpose of this study is to examine consumers' recognition, purchase intention, price acceptability of carving decoration, which can be said to be one part of food-space presentation, food styling, and table decoration. For this, a survey was carried out to target adults in over 20 years old who use a bus and a subway during morning and evening time in Daegu area from May 18, 2009 to May 22, 2009, and 296 copies were used for the final analysis. As a result of the research, over 50% of the consumers know about carving, saying they have come to mow it mostly through TV. Carving was mentioned to be probably used the most in buffet restaurants and other types of restaurants, and to be likely to be used the most in buffet restaurants and Japanese-style food Also, they responded that flower-butterfly carving & Japanese-style food, animal-form carving & Chinese-style food, and watermelon carving & buffet are harmonized the most. In addition, consumers with high recognition of carving decoration were indicated to be high in purchase intention and price acceptability. Also, Consumers with low recognition of carving decoration perceive very low price acceptability even if being high in purchase intention. However, when purchase intention of consumers with high recognition of carving decoration was high, price acceptability was indicted very highly.

• Culinary science and hospitality research
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• v.21 no.5
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• pp.98-108
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• 2015

The provincial education office considers providing school lunch as a foodservice and intends to improve consumer satisfaction. This study investigates the effect of student food habits and perceived food quality on satisfaction with school lunch based on Oliver's expectancy disconfirmation theory. We test the moderating effect of student gender and school conditions, such as the location of the school, job positon of the nutrition teacher, renovating kitchen and food distributing place. Questionnaires were collected from 240 sixth graders in the eight elementary schools in Gyeonggi province from August to September 2014. Excluding inadequate questionnaires, 208 were analyzed. PLS (Partial Least Square) and bootstrap t-tests were conducted for this study. The results showed food habits affected satisfaction directly (p<0.01). The perceived food quality of the school lunch service mediated this relationship in part (p<0.01). Moderating effects identified were gender (p<0.1), nutrition teacher's position(p<0.05), and renovating kitchen (p<0.1), but not location of school or distributing place. The study revealed the importance of student food habits and perceived food quality, which had an influence on satisfaction. We make a distinction between the concepts of satisfaction and quality so as to improve student satisfaction. When it comes to offering education program about food habits, the schools with old-fashion kitchen is given priority to than renovating one.

• Journal of Dental Rehabilitation and Applied Science
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• v.16 no.2
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• pp.105-112
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• 2000

In-Ceram system is one of contemporary esthetic all ceramic restorations and has relatively high flexural strength. The purpose of this study was to evaluate the marginal fit of In-Ceram crown according to shoulder width and measuring position. In this study, twenty seven In-Ceram crowns devided into three groups, each prepared with shoulder width of 0.6mm, 0.9mm and 1.2mm. All specimens were cemented with glass ionomer cement. After cementation, specimens were measured marginal gap between the margin of the In-Ceram crown and the finishing line of resin master die by using a refrective microscope. Marginal gaps were recorded at the labial, lingual, mesial and distal measuring points on the resin master die. The results of this study were as follows: 1. Mean marginal fits of each group were $81.28{\mu}m$ in 0.6mm shoulder width, $70.78{\mu}m$ in 0.9mm shoulder width and $67.75{\mu}m$ in 1.2mm shoulder width. 2. There was significant difference between group 0.6mm and 0.9mm, 1.2mm.(p<0.05). 3. In comparison of marginal fit according to the measuring points, there was no significant difference.

• The Journal of the Acoustical Society of Korea
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• v.21 no.4
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• pp.361-373
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• 2002

In this paper, we propose a channel normalization method to improve the performance of CMS (cepstral mean subtraction) which is widely adopted to normalize a channel variation for speech and speaker recognition. CMS which estimates the channel effects by averaging long-term cepstrum has a weak point that the estimated channel is biased by the formants of voiced speech which include a useful speech information. The proposed Formant-broadened Cepstral Mean Subtraction (FBCMS) is based on the facts that the formants can be found easily in log spectrum which is transformed from the cepstrum by fourier transform and the formants correspond to the dominant poles of all-pole model which is usually modeled vocal tract. The FBCMS evaluates only poles to be broadened from the log spectrum without polynomial factorization and makes a formant-broadened cepstrum by broadening the bandwidths of formant poles. We can estimate the channel cepstrum effectively by averaging formant-broadened cepstral coefficients. We performed the experiments to compare FBCMS with CMS, PFCMS using 4 simulated telephone channels. In the experiment of channel estimation, we evaluated the distance cepstrum of real channel from the cepstrum of estimated channel and found that we were able to get the mean cepstrum closer to the channel cepstrum due to an softening the bias of mean cepstrum to speech. In the experiment of text-independent speaker identification, we showed the result that the proposed method was superior than the conventional CMS and comparable to the pole-filtered CMS. Consequently, we showed the proposed method was efficiently able to normalize the channel variation based on the conventional CMS.

• The Journal of the Acoustical Society of Korea
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• v.34 no.1
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• pp.12-19
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• 2015

In this paper, temporal variations of acoustic transmission loss (TL) affected by internal tide are studied by computer simulation using oceanic data measured in the southern sea of Jeju Island in summer. Temperature was measured with depth (bottom depth are nearly 80 m) in two sites near Seogwipo coast every one hour for 25 hours during July 27 and 28, 2009. The periodic fluctuation of temperature due to the internal tide was observed and its vertical displacement was more than 10 m. In order to investigate temporal variation of TL by internal tide, acoustic propagation between two measurement sites (3.8 km distance) was simulated with a source depth of 10 m. TL variation for 1/3 octave band of 100 Hz center frequency highly coincided with tidal period but more complex variation with indistinct tidal period was observed for 1 kHz. Maximun standard deviation of TL variation was 4.2 dB for 100 Hz at 2.8 km distance from a source and it was 3.7 dB for 1 kHz. The tidal variation was also shown in detection range and its maximum variance was less than 1 km. These results imply that temporal variation of TL should be considered for acoustic researches at the southern sea of Jeju Island.