• Korean Journal of Environmental Biology
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• v.29 no.4
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• pp.362-372
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• 2011

The relationships among total epiphytes, algal epiphytes and eelgrass ($Zostera$ $marina$ L.) were studied at eelgrass medows from July, 1998 to July, 1999 in Yulim-ri, Yeosu, Korea. Epiphytic diatoms on eelgrass leaves were observed from July to December 1998. From the results of this study, we inferred the following three (3) conclusions : 1) As eelgrass grew older, biomass of epiphytes increased, according to relationships between the leaf length and area of eelgrass and biomass (DW, AFDW and Chl. $a$) of epiphytes. 2) According to the ratio of dry weight, ash-free dry weight and Chlorophyll of epiphytes, the algae with calcareous or siliceous skeletons, such as coralline algae or diatoms, were dominated in the epitphytic algae community. 3) The autotrophic index (AI) calculated from AFDW and Chl. $a$ of epiphytes varied from 151 to 375. However, the period of autotrophic community was shorter than heterotrophic community and the value of AI was high. From these results, we inferred that heterotrophic community, including detritus or microorganisms were dominated in the most of research period.

• School Mathematics
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• v.18 no.4
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• pp.749-771
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• 2016

The purpose of this study is to analyze mathematical tasks of Korea and the USA textbooks focused on conditions for parallelograms. In this study, structures of task, types of proof and reasoning, and levels of cognitive demand are investigated. The conclusion is as follows: First, with respect to structures of task, structures presented in the USA textbooks are more diverse. Second, with respect to types of proof and reasoning, Korea and the USA prefer IC task and DA task. And task types presented in the USA textbooks are more diverse. Third, with respect to levels of cognitive demand, in both Korea and the USA textbooks, PNC task and PWC task account most. And compared to the USA, Korea prefer algorithms. In addition, we find out implications for reconstruction of Korea textbook. It is as follows: First, with respect to structures of task and types of proof and reasoning, the diversity of composition needs to be raised. Second, with respect to levels of cognitive demand, the concentration in PNC task needs to be declined. And levels of cognitive demand on types of tasks need to be reconsidered. Third, with respect to tasks' topic and material, internal and external connectivities of mathematics need to be strengthened.

• Journal of Navigation and Port Research
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• v.33 no.3
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• pp.181-191
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• 2009

In general, seafarer's human error is considered to be the preponderant muse for the majority of maritime transportation accidents in a merchant ship. The implementation techniques for Human Error Model (HEM) to assess possible accident risk by deck officers including captain, chief officer, second mate and third mate are described in this study. The scope of this work is focused to 642 deck officers in the ship management company with 130 vessels. At first, HEM can be constructed through the statistical analysis and expert's brainstorming process with human data to 642 deck officers. Then the variables $\upsilon$ for the human factors, the evaluation level EP($\upsilon$) for $\upsilon$, the weight $\alpha$ of $\upsilon$, and the title weight $\beta$ of each deck officers can be decided. In addition, through the analysis of ship's accident history, the accident causation ratios by human error ${\gamma}_H$ and by external error ${\gamma}_B$ can be found as 0.517(51.7%) and 0.483(48.3%), respectively. The correlation coefficients to $\upsilon$ are also shown significant for a 95% confidence interval (p < 0.05) for each coefficient. And the validity of HEM is also surveyed by the analysis of normal probability distribution of risk level RL to each deck officer.

• Review of Culture and Economy
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• v.21 no.2
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• pp.29-51
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• 2018

The Korea-USA FTA was activated in 2012 and evaluated highly on market-opening among FTA agreements which the Korea government has signed. This paper empirically examines the impact of the Korea-USA FTA on the Korea content industry trade performance with USA. Using ANOVA analysis, the study tested primarily whether there are difference in content exports and imports in a korea-US trade between before and after of Korea-USA FTA in 2012, the year of the entry into force of Korea-USA FTA. Using content industry exports and import data over the period 2007-2015, we find that Korea content export to US after 2012 is significantly different from one before 2012, and there is no difference in import. Based on a regression analysis, we also tested the impact size of Korea content export performance in Korea-USA FTA. The result is that coefficient of FTA dummy variable is not significant, meaning that even though there are some difference in korea content export to US between before and after of Korea-USA FTA, the Korea-USA FTA agreement itself is not a key factor which increase the Korea content export volume to USA market.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.5
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• pp.352-362
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• 2019

The study investigates one of the long-standing, but still controversial issues in modern finance from the international and domestic perspectives. That is, financial components and differences on corporate profitability are identified and compared under the primary hypotheses. Empirical research settings include the sample data as KOSPI-listed chaebol firms, time reference covering the post-era of the global financial turmoil and two differently defined profitability indices measured by the market- and the book-value bases. A majority of total 7 explanatory variables except firm size and leverage ratio reveal their statistically significant power to explain profitability indices for the chaebol firms in the first hypothesis. The results are generally compatible with those obtained from their counterparts of non-chaebol firms. In the second hypothesis applying multinomial logistic model, the chaebol firms are classified into three groups according to the level of profitability. It is then confirmed that variables to represent the market-valued debt ratio, business risk and growth potential are financially discriminating factors among the three groups. The study may provide a new vision to identify financial factors of corporate profitability for Korean chaebol firms after the global financial crisis, which can enhance the benefits of interested parties at the government or corporate level in a virtuous cycle.

• Journal of The Korean Association For Science Education
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• v.28 no.1
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• pp.32-46
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• 2008

The purpose of this study was to analyse the qualitative and quantitative characteristics of paper-pencil tests for exploring its appropriateness as a selection tool of the gifted in science. For this purpose, we developed two (internal and external) item analysis frameworks, and applied these frameworks to analyse qualitative characteristics. Also, we analysed the relationship between two characteristics. The results of analysing qualitative characteristics revealed that the portion of items with acceleration context exceeding middle school curriculum level was relatively large, which caused low content validity. Furthermore, there was considerable deviation in content and context by subject matter and year, which caused test unstability. Items measuring knowledge domain was the most prevalent, and too much weight on data interpretation & analysis domain in inquiry process skills. In case of creativity test, the portion of items measuring convergent thinking was much larger than that of divergent or associative thinking. Most of these items were represented by using pictures and tables rather than using graphs. Item types of multiple-choice and short answers were superior to essay types. Discrimination index, on the whole, was appropriate (above 0.3), but item difficulty showed a vast deviation ($0.01{\sim}0.90$). Correlation coefficients among subject matters and test tools were very low, and test reliabilities were also low. Low item difficulty & high discrimination index item types were distinguishable. Items with acceleration context were more discriminating than enrichment context. Implications of developing quality paper-pencil test items in the selection of gifted students are discussed.

• Journal of The Korean Association For Science Education
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• v.27 no.3
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• pp.201-211
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• 2007

The purposes of this study were to examine trends in Korean middle school students' attitudes toward science and the differences in boys' and girls' attitudes toward science as well as to analyze Korean middle school students' attitudes toward science compared to those in Singapore, Chinese-Taipei, Hong Kong, and Japan. In order to achieve these purposes, we analyzed students' survey data on self-confidence in science, interests in science, external motivation for science, and career preference for science collected from TIMSS 1995, TIMSS 1999, and TIMSS 2003. Korean students' interests in science and external motivation for science reduced in TIMSS 1999 and increased again in TIMSS 2003. The amount of change was greater in interests in science. On the other hand, self-confidence in science and career preference for science consistently declined from TIMSS 1995 to TIMSS 2003. Self-confidence in science among boys and girls was similar in TIMSS 1995 and 1999. But self-confidence of girls in science declined rapidly from TIMSS 1999 to 2003, while self-confidence of boys in science remained almost the same. Trends of interests in science were similar between boys and girls; they declined in TIMSS 1999 and increased again in TIMSS 2003. External motivation for science of both boys and girls increased, and the increase among girls was greater. The percentage of boys who wanted to have a job using science consistently declined from TIMSS 1999 to TIMSS 2003, while the percentage of girls declined in TIMSS 1999 and increased in TIMSS 2003 again. The results from an international comparison with other Asian countries having similar cultures showed that Korean students' self-confidence in science, career preference for science of middle school students was the lowest.

• Korean Journal of Ecology and Environment
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• v.44 no.3
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• pp.264-271
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• 2011

At the Jangheung multipurpose dam, which is on the Tamjin River, a trapping and trucking operation was established to maintain continuous upstream migration of fish,. To facilitate fish gathering, installation of an effective fishing trap was required. In this study, we evaluated the fish trap, established at the Jangheung dam, using PIT (Passive Integrated Transponder) telemetry. A total of 254 individuals from 15 species were monitored. Among these tagged species, 36 individuals from 6 species (Carassius auratus, C. cuvieri, Zacco temminckii, Z. platypus, Pungtungia herzi, and Pseudobagrus koreanus) were detected; a 14.2% detection rate. C. auratus recorded the highest detection rate of 44.2% while P. herzi was 14.3%. Z. temminckii and Z. platypus showed relatively low detection, 5% and 7.7% respectively. Some of individuals from C. auratus and Z. platypus did not pass through the antenna at the first attempt but were continuously detected on multiple days. There were no statistical differences in body size (total length, standard length and body weight) of individuals that did or did not swim into the trap (Mann-Whitney U test, p>0.05). Fish mainly swam into the trap during outflow of water from the dam (Mann-Whitney U test, p<0.001) and showed a higher detection frequency in daytime than nighttime (Mann-Whitney U test, p<0.001). Thus, for fish movement into the trap, external factors such as outflow from dam and time of day have important roles. Based on detection rate, not all fishes showed upstream migration but represented selective migration. Consequently, the establishment of flexible outflow strategies that take into consideration ecological characteristics of fishes should required for improving the efficiency of fishway.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.34 no.1
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• pp.53-70
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• 2016

Korean temple gardens have very high preservation value as the place reflecting ancestral wisdom in harmony with nature. Not only as a religious place but also as a beautiful landscape place, many people including foreigners are visiting traditional Korean temples. However, current many Korean temple gardens lost their original value and meaning because of the inappropriate planting in traditional places. In this study, for maintaining the representativeness of traditional Korean temple, we researched the current planting status of traditional Korean temple. After the research of 51 traditional Korean temples, a total of 207 species of plants was investigated, and among them 128 species (61.84%) were Korean native plants, 76 species (36.71%) were cultivar plants, 2 species (0.97%) were naturalized plants, and 1 species (0.48%) is introduced plant. Korean red pine (46 temples), sawleaf zelkova (38 temples), and ginkgo (36 temples) were the high rank species among 207 species. Korean rare plants including black-fruit hackberry and Korean fir form 5.3% of total species, and Korean endemic plants including Korean weigela and Korean paulownia form 3.4% of total species in traditional Korean temples. On the other hand, plants that have religious meaning such as lotus, musa, and guelder rose form slightly. There is a higher proportion of traditional Korean plants than religious meaning plants in traditional temple gardens, so that temple gardens are highlighted as historic places. Based on the planting status, maintenance plans were established reflecting characteristics of each spaces: entry space, the precincts of a shrine, and flower stairs. As a result, we suggest that selecting a suitable plant species with regard to the religious meaning of the plant symbolism for newly designing Korean temple gardens.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.12
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• pp.1865-1872
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• 2015

This study attempted to investigate consumer perceptions and attitudes towards reducing sugar intake by providing data to develop guidelines for the government and food-related industries to encourage Korean consumers to maintain appropriate levels of sugar intake. A survey was conducted on 238 adult consumers regarding their purchasing power for products with high sugar content in Seoul and Bundang, Gyeonggi area from September 1~30, 2013. Nutritional information on sugary products had a greater impact than media and others' recommendations on consumer awareness regarding need to reduce sugar intake. External factors such as health and weight control were stronger reasons for consuming reduced amounts of sugar or sugar-free products than internal factors such as sweetness. However, internal factors-such as taste-did not have a greater effect on consuming reduced amounts of sugar or sugar-free products than environmental factors-such as absence of purchase channels. Consumers indicated higher acceptance for 50% reduction in sweetness of existing commercial products. Regarding methods of lowering sugar intake, sugar replacement and reducing sugar consumption both generally and at home were preferred. In addition, consumers were likely to pay 10~14% more for sugar-reduced products than for existing products. Overall, consumers expressed positive attitudes towards reducing sugar intake in the future, although those in their twenties tended to be more passive than other age groups.