• Journal of The Korean Association For Science Education
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• v.35 no.4
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• pp.629-648
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• 2015

This study is a case study examining how research-based 'authentic' science education program contextually facilitates students' learning on NOS as a process. We developed 'Becoming a Scientist' mentor-mentee program and applied it to six Korean 7th graders for 8 months. A mentor, who is also a researcher, provided scaffolding and coaching, and her mentees were to perform the whole process of science research, including selecting the research subject and questions, planning research design, doing experiments, collecting and analysing data, writing research paper, and experiencing poster presentation at an academic conference. The research questions are 1) What would the students experience at every step of their research process?, and 2) Which perceptions would they construct NOS as a process? Data include classroom observations, interview, mentor's journal, and students' learning products. The results show that the mentees have experienced their views of NOS as a process in various ways such as role of research question and purpose, validity of measured value, researcher's subjectivity in interpreting data, experience of making public and peer review, and significance of academic conference. This study has shown that students' actual experience in scientific research enhanced their views about NOS as process without explicit and reflective approaches. We defined 'authenticity' associated with not only with its similarity to what scientists do but to learner's identity as scientific researcher. Based on the situated learning theory, this study sheds light on the necessity of reconsideration about the meaning of authenticity and embodying authentic context in science education for better NOS learning.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.39 no.1
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• pp.33-43
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• 2003

The midwater pair trawl which is being used at present in Korea have several problems. Firstly, it is difficult to control the net height on high towing speed. Secondly, net breaking often occurs owing to floats and thirdly, the volume of net on the net drum is so large. This study is aiming for examining the possibility of application for the Korean midwater pair trawl through the model experiment of non-float midwater pair trawl. The model of non-float midwater pair trawl was manufactured as 1/100 of the full scale net which is being used in bottom pair trawl for 850ps class considering the Tauti's Similarity law. The model experiment was carried out to analyze the opening efficiency according to the variation of lower warp length and the opening efficiency was investigated between th proto type and non-float type. The results obtained can be summarized as follows ; 1. The hydrodynamic resistance of non-float type was about 10~20% smaller than that of the proto type and it increased about 1ton according to the increase of dL at the condition of the same flow speed. The resistance acting on the lower warp decreased about 5% but that of the upper warp increased according to the increase of lower warp length (dL) at the condition of the same flow speed. 2. The net height of the non-float type decreased almost linearly according as the increased of flow speed and it increased in a logarithmic functional form with the increase of the lower warp length at the condition of the same flow speed. On the decreasing rate of the net height, the non-float type was lower than the proto type and the difference of the decreasing rate was about 12% at 3.0 knot, 25% at 4.0 knot, 25% at 4.0 knot respectively when dL was 30m. 3. The net width of non-float type was not varied so much as only 2m range and was larger than that of proto type. 4. The mouth area of non-float type decreased in a exponential functional form. On the decreasing rate of the mouth area, the non-float type was lower than the proto type. The filtering volume increased in a logarithmic functional form with increasing flow speed and the filtering volume of proto type decreased steeply over 3.0knot, but that of non-float type increased until 4.0knot. 5. The optimal length of lower warp was when the value of dL was about 30m and the optimal position of front weight was at the connection point of four net pendants.

• Journal of Wetlands Research
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• v.12 no.3
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• pp.1-13
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• 2010

Most of investigations about the effects of dam construction on the surrounding environments have focused mainly on the change of climate conditions and crop production. In order to research the effect of dam construction on the surrounding vegetation, we chose the Soyanggang dam whose storage capacity is the largest in Korea, and was built 33 years ago. We surveyed and analyzed the surrounding vegetation by using quadrat method and measured the soil moisture content among floodplain (FP), 5m above the flood plain (AFP) and control group (CG) which is 3km far from the lake through ridge. The largest value of mean importance percentage of the canopy~understory layer at FP was Salix koreensis (87.9%) and those of AFP and CG was Quercus mongolica (38.9% and 40.4% respectively) and the largest important percentage of the herb layer at FP was Artemisia capillaris (34.2%) and those of AFP and CG was Oplismenus undulatifolius var. undulatifolius (9.4% and 24.6% respectively). The Shannon-Wiener diversity index of shrub~canopy layer at FP (0.26) was lower than AFP (2.34) and CG (2.23) and there was not any significant difference in the herb layer among three groups. The S${\o}$rensen similarity index between FP and AFP, FP and CG was 0, and that of AFP and CG was relatively high. The highest density of tree and subtree with the DBH level of FP was S. koreensis of 5~10cm (240/ha), and that of AFP and CG was Quercus spp. of 15~20cm (400/ha and 466/ha respectively). And the highest density of seedlings of FP was Pinus densiflora (7,040/ha), and that of AFP and CG was Quercus spp. (720/ha and 400/ha respectively). The soil water content of FP (6.28%) was relatively lower than AFP and CG (11.13% and 10.14% respectively; p<.01). These results indicated that construction of Soyanggang dam changed the vegetation of the floodplain, without showing a change in its upland areas.

• Korean Journal of Ecology and Environment
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• v.50 no.1
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• pp.137-147
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• 2017

The identity of toxin producers remains only hypothesis unless there were identified by strain isolation and analytical confirmation of both the cyanotoxin production and the genetic identity of the monoculture. The purposes of this study were to identify a morphologic and phylogenetic classification in Aphanizomenon flos-aquae strains isolated from the Nakdong River and to investigate the potential ability of the strains to produce toxins such as saxitoxin and cylindrospermopsin using target genes. The 16S rRNA and sxtA, sxtI, cyrA, cyrJ genes were analyzed on two strains (DGUC001, DGUC003) isolated from the Nakdong River. Morphological features of the strains were observed a shape of aggregated trichomes in parallel fascicles which can reach up to macroscopic size and a hyaline terminal cell without aerotope. In addition, the 16S rRNA phylogenetic analyses showed that the strains were identified as the same species with high genetic similarity of 98.4% and grouped within a monospecific andsupported cluster I of Aphanizomenon flos-aquae selected from GenBank of the NCBI. The cyrA and cyrJ genes encoding for the cylindrospermopsin-biosynthesis were not detected in the present study. The sxtA gene was in detected both the two strains, whereas the sxtI gene which had been suggested as a suitable molecular marker to detect saxitoxin-producing cyanobacteria was not found both the strains. Thus, the two strains isolated from Nakdong River were identified as the same species of Aphanizomenon flos-aquae Ralfs ex Bornet et Flahault 1888, the two strains were confirmed as potential non-producing strains of the saxitoxin and cylindrospermopsin.

• Food Science and Preservation
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• v.20 no.4
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• pp.524-531
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• 2013

We investigated the quality characteristics of the Korean and American blueberry. There was a similarity between the general composition and sugar content of the Korean and American values. The pH values showed a low of 3.46 in American blueberries to a high of 4.49 in Korean blueberries. The L (lightness), a (redness), and b (yellowness) value scores of the American blueberry were higher than the Korean blueberry. The levels of total phenol content and DPPH radical scavenging abilities were 205 mg%, 93.48% in the Korean blueberry and 182 mg%, 84.32% in the American blueberry, respectively. The free sugar levels showed fructose 2,514 mg%, glucose 2,315 mg%, and sucrose 69 mg% in the Korean blueberry, while the free sugar levels of the American blueberry showed fructose 2,106 mg%, glucose 1,825 mg%. The contents of organic acid were lactic acid and tartaric acid in the Korean blueberry, while the organic acid in the American blueberry contained tartaric acid, succinic acid, oxalic acid, and lactic acid. The Korean blueberry has 12 kinds of free amino acids, while the American blueberry has 9 kinds of free amino acids. Furthermore, the Korean blueberry contains 390 mg% of total amino acids, which was higher than 32% in the American blueberry with 295 mg% of total amino acids. The fatty acid contents of the American blueberry (2,897 mg%) was higher than that of the Korean blueberry (2,783 mg%) as well as in the oleic acid, linoleic acid, and palmitic acid. The mineral contents of all the samples were P>K>Ca>Mg, respectively. Given the above results, the Korean blueberry bioactive chemicals or properties were thought to be somewhat higher than the American blueberry.

• Economic and Environmental Geology
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• v.8 no.3
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• pp.147-164
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• 1975

19 amphibolite samples from the Precambrian Sobaegsan metamorphic belt including the Ogbang mine amphibolites were analyzed for 24 elements each, by wet chemical and emission spectroscopic methods. All the chemical data were evaluated by the methods outlined by Evans and Leake(1960) and Leake(1964) and by Shaw and Kudo(1965). The chemical similarity of all the studied rocks analyzed to basic igneous rocks is consistently indicated particularly by trace element abundance and variation trends. Petrography and oxidation ratios were also considered in attempting to determine the nature of the parent rocks. 3 analyses of W-bearing mafic metamorphic rocks from Sangdong area of the Ogcheon geosynclinal zone are also presented and discussed. Geochemical data for these latter rocks have been possibly derived from mafic tuffs deposited in an area of carbonate deposition.

• Journal of Korean Society of Transportation
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• v.23 no.1
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• pp.93-102
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• 2005

An Origin-Destination (O/D) is considered as one of the important information in route choices and trip assignments. A household interview survey is deemed to be the traditional and the most widely used method in making sample O/D and its conversion to the total O/D. Some researchers have studied to estimate dynamic O/D from the relationship between link volumes and trip assignment model. Nowadays, owing to the recent rapid spread of cellular phones. Location information of the cellular phone through the Base Station(BS) is considered as an alternative to O/D estimation. In this study, the methodology of generating BS-based O/D and the methodology of converting this O/D into an administrative district-based O/D are proposed. The information of GPS positions and cellular BS positions have acquired by establishing GPS equipment and cellular phone on taxies in Cheongju. Three weeks data are collected and used in estimating O/D by matching them on a digital map. Scatter diagram and sample correlation coefficients are used to investigate the similarity of the GPS-based O/D pattern among weeks, among days, and among times in day. The results show that there are few significant differences among weeks. But there is a difference in O/C pattern between weekday and weekend. Furthermore, there is a difference between morning peak and afternoon peak. Two methodologies are proposed to convert BS-based O/D into an administrative district-based O/D. The first one is to use the distribution pattern of GPS coordinates, the other is to use the coverage area of the BSs. To validate such converted O/D, GPS O/D is used as a true value. The statical analyses through scatter diagram, MAE and RMSE shows that there is few significant defference of pattern between the estimated BS-based O/D and GPS O/D. In the case of using only cellular information, the methodology using coverage area of the BSs is recommended for estimating O/D.

• Korean Journal of Plant Resources
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• v.13 no.3
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• pp.227-242
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• 2000

Site characteristics, vegetation structure and dynamics of Kalopanax septemlobus forests in Mt. Heungjeong, Mt. Balwang and Mt. Gariwang were studied to provide the information need for national resources conservation and restoration of K. septemlobus forest in Gangwon-do of Korea. The K. septemlobus forests were distributed at 780m to 1,300m in altitude, steep slope, ridges-slope areas with facing northeast to northwest in good nutrition area. The annual diameter growth of those trees ranged 1.60mm to 2.41mm. Forty-three plots(20$\times$20m) were set up at three natural population of Kalopanax septemlobus forest and TWINSPAN method was used for vegetation structure analysis. The result of TWINSPAN ordination show that geographical features played a role in determining community types in the study areas. Community type of the study areas classified into three groups by TWINSPAN; K. septemlobus-Quercux mongolica- Acer mono community(Mt. Balwang), K. septemlobus-Q. mongolica- Tilia amurensis community(Mt. Heungjeong), K. septemlobus-Betula costata-Q. mongolica community(Mt. Gariwang). In most of the K. septemlobus forests, major woody species appeared predominantly were Q. mongolica, T. amurensis, Acer pseudo-sieboldianum, Lindera obtusiloba, A. mono, Magnolia sieboldii, Ulmus davidiana var. japonica. And also, Those species were surveyed in all the areas. Species diversity(H') of investigated areas ranged 0.3124~0.13992 and this value relatively higher than that of other forests with similar site. The range of similarity indices between surveyed areas was 64.1~64.54%. The distribution pattern of Morista's index show that Kalopanax septemlobus distributed randomly in tree and concentrated a few sample plots in subtree layer and shurb layer. K. septemlobus occupied 37.1~58.8% of tree layer story, 8.4~17.6% of subtree layer, 0~0.38% of shurb layer each surveyed area. The association analysis showed that Kalopanax septemlobus positively associated with Betula ermani, Deutzia glabrata, Carpinus cordata, Fraxinus mandshurica and negatively associated with Symplocos chinensis var. pilosa, Styrax obassia, Acer mono, Euonymus macroptera, Ulmus davidiana var. japonica. According to the diameter distribution of Kalopanax septemlobus community, the community of Mt. Gariwang will gradually decline and replaced by Quercus community. The communities of Mt. Heungjeong and Mt. Balwang has its seedlings and saplings, so it may be sustained.

• Korean Journal of Remote Sensing
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• v.34 no.6_1
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• pp.953-968
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• 2018

In order to understand the change of surface water temperature in the East China Sea (ECS), this study analyzed the relationship between sea surface temperature (SST), air temperature (AT) and heat flux using satellite and model reanalysis data from 2003 to 2017. SST in the ECS showed the lowest (average : $13.72^{\circ}C$) in March and the highest (average : $28.12^{\circ}C$) in August. AT is highly correlated with SST and shows a similar seasonal change. In August, SST is higher than AT and then continuously higher than AT until winter. To analyze the change of the summer SST in the ECS, we used the SST anomaly value in August to classify the periods with positive (04', 06', 07', 13', 16', 17') and negative (03', 05', 08', 09', 10', 11', 12', 14', 15') values. Spatial similarity between the two periods indicates that SSTs are relatively larger variations in the northern part than in the southern part, and in the western part than in the eastern part in the study area. AT and net heat flux values also show similar changes with SST. However, the periods of the positive SST anomaly have the relatively increasing SST, AT and heat flux values compared to the periods of the negative SST anomaly in the summer season of the ECS. Although the change of SST in the summer season generally well correlates with AT, there were the periods when it was different from general trends between SST and AT (10', 12', 15', 16'). SST in August 2010 and 2012 decreased by $0.5^{\circ}C$ from AT. It suggests that the decreasing SST was considered to be caused by the effects of the typhoon passing through the study area. In August 2015, AT was relatively lower than SST (> $0.5^{\circ}C$), which is might be weakening of the East Asian Summer Monsoon. In August 2016, SST and AT show the highest values during the whole study periods, but SST is higher than AT (> $1^{\circ}C$). From satellite and heat flux data, the variations of SST have been shown to be relatively higher in the area of the expansion Changjiang Diluted Water (CDW) originated from the China coast. More research is needed to analyze this phenomenon, it is believed as not only the effect of rising AT but also the expansion of the low-salinity water.

• Journal of the Korean Society of Floral Art and Design
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• no.45
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• pp.77-95
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• 2021

This study considers the problem of reality that our floral art has to overcome as a loss of the floral art spirit caused by the expansion of Western-centered formalism flower culture, and considers the discussion on the deformality of distancing and the free spirit of nomadism. The floral art, which works on the creator's aesthetic mental world through flowers, is an art of mental image that values the free mental world of the creator. It also refers to the importance of artist consciousness as an art of self-imago that makes the target world beyond the "expression of similarity" that reproduces the target world. In this context, the lack of concern about the identity of Korean floral art appears to be the creative training and work of Korean floral artists who are biased toward Western expression techniques and creative methods. It also expresses a problem with our cultural consciousness, which is dominated by the Western flower culture of flower design. Here, we are obliged to understand the reality of Korean floral art biased by Western flower design and to organize discussions to solve the problem. Therefore, this study examines the problems that our floral art has to overcome as part of seeking the identity of Korean floral art and enhancing the cultural value of Korean floral art through criticism of Western cultural acceptance. This is a historical consideration of the nature of Korean floral art to recover, while also a process of identifying the meaning of the free creative spirit that the artist should maintain as an aesthetic art. Furthermore, such criticism of the Korean floral art culture and discussion of introspection are expected to serve as an opportunity to further expand the academic discourse system for the floral art while embodying the "identity" of Korean floral art.