• Journal of The Korean Association For Science Education
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• v.38 no.4
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• pp.495-504
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• 2018

This study was conducted to develop items to measure scientific core competency based on statements of scientific core competencies presented in the 2015 revised national science curriculum and to identify the validity and reliability of the newly developed items. Based on the explanations of scientific reasoning, scientific inquiry ability, scientific problem-solving ability, scientific communication ability, participation/lifelong learning in science presented in the 2015 revised national science curriculum, 25 items were developed by five science education experts. To explore the validity and reliability of the developed items, data were collected from 11,348 students in elementary, middle, and high schools nationwide. The content validity, substantive validity, the internal structure validity, and generalization validity proposed by Messick (1995) were examined by various statistical tests. The results of the MNSQ analysis showed that there were no nonconformity in the 25 items. The confirmatory factor analysis using the structural equation modeling revealed that the five-factor model was a suitable model. The differential item functioning analyses by gender and school level revealed that the nonconformity DIF value was found in only two out of 175 cases. The results of the multivariate analysis of variance by gender and school level showed significant differences of test scores between schools and genders, and the interaction effect was also significant. The assessment items of science core competency based on the 2015 revised national science curriculum are valid from a psychometric point of view and can be used in the science education field.

• Journal of Bio-Environment Control
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• v.26 no.4
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• pp.333-339
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• 2017

This research was aimed to establish rapid analysis technique for the determination of nitrate ($NO_3{^-}$) concentration in the leaves of paprika, which has key role for the stable vegetative and reproductive growth. Leaf petiole and blade sap of two paprika cultivars ('Raon red' and 'Raon yellow') were used for the determination of $NO_3{^-}$ concentration, separately using rapid detection kit (RQ-flex) and spectroscopy quantification methods. In addition, two paprika cultivars namely, 'Nicole' and 'TP2001' were used to determine the status of $NO_3{^-}$ concentration in leaf of each fruiting group. $NO_3{^-}$ concentration in leaf blade sap and the content in leaf showed significant correlation ($R^2=0.8628$), analysed by RQ-flex and spectroscopy methods, respectively. Furthermore, leaf petiole sap and the content in leaf also showed significant correlation ($R^2=0.6734$) but the relationship was poor compared to leaf blade sap and the leaf content. $NO_3{^-}$ concentration in petiole sap decreased in all the cultivars from early to late fruiting group. The higher concentration in the lower leaves and the continuous decrease towards the upper leaves in the both years were found through the analysis of $NO_3{^-}$ concentration in different leaf position. In addition, daily short-term fluctuation of $NO_3{^-}$ in petiole sap could be rapidly monitored. These results showed that long-term or short-term monitoring by test strip-based rapid analysis technique might be useful tool for the diagnosis of nutritional status for the stable of nutritional management in paprika.

• Journal of Bio-Environment Control
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• v.26 no.4
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• pp.368-377
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• 2017

This study investigated the possibility of application of the recently introduced cylindrical paper pot seedlings in hot pepper (Capsicum annuum L.) cultivation. The seedling growth, initial rooting after planting and accumulated fruit yield were investigated with the treatments of tray type (paper pot and plug) as a main factor, tray cell number (40 cell and 50 cell) as a sub-factor, and fertigation method (continuous fertigation and fertigation after 35 days sowing) as a sub-sub factor, respectively. The growth of pepper seedlings was significantly affected by tray type and fertigation method showing the highest value at 50 cell plug tray with continuous fertigation, and the effect of fertigation was greater than that of trays. 'Cheongyang', 'Daekwonseoneon' and 'Longgreenmat' cultivar showed all the same pattern in seedling growth. These three-cultivar seedlings were planted in plastic house and in open field in Jeonju area, respectively, and another 'Daekwonseoneon' seedlings raised Yeongyang local area was also planted at the same area. There was no difference in the rooting of 'Cheongyang' pepper at 2 weeks after planting in plastic house. The accumulated fruit weight was not significantly different between paper pot seedlings and plug seedlings in three cultivar grown in plastic house. However, that of 'Cheongyang' pepper showed higher at paper pot seedlings than plug seedlings and the other two cultivar were higher at plug seedlings in open field. 'Daekwonseoneon' pepper yield grown in open field in 'Yeongyang' area was not significant between paper pot seedlings and plug seedlings. In conclusion, the pattern of seedlings growth grown in the cylindrical paper pot was the same as those of the conventional plug seedlings and also fruit yield was similar between paper pot seedlings and plug seedlings even though minute difference among cultivars. These results suggest that pepper seedlings grown in paper pot should be highly applicable to pepper cultivation.

• Communications of Mathematical Education
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• v.20 no.2 s.26
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• pp.295-326
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• 2006

Despite the importance of mathematics education, many students in high school have lost their interests and felt difficulties and they don't have 'mathematical' experience with meanings attached because of the entrance examination. This paper attempted to resolve these problems and find the teaching-method with which students can study by themselves with more confidence. Nowadays students' use of Internet is very popular. After develop 'the development of mathematical power' program based on mathematics history, history, science, the application of problems in real world, and self-evaluation, I made students repeat them after making teaching lessons in classroom as moving pictures. Through this processes, I attempted to develop the Self-Directed Learning' ability by making public education substantial. First of all I analyzed the actual conditions on 'Self-Directed Learning' ability in mathematics subject, the conditions of seeing and hearing in Internet learning program, and students' and their parents' interests in Internet education. By analyzing the records, I observed the significance of the introducing mathematics history in mathematics subject in early stager, cooperative-learning, leveled-learning, self-directed learning, and Internet learning. Actually in aspect of applying 'the development of mathematical power' program, at first I made up the educational conditions to fix the program, collected the teaching materials, established the system of teaching-learning model, developed materials for the learning applying Internet mail and instruments of classroom, and carried out instruction to establish and practice mathematics learning plan. Then I applied the teaching-learning model of leveled cooperation and presentation loaming and at the same time constructed and used the leveled learning materials of complementary, average, and advanced process and instructed to watch teaching moving pictures through Internet mail and in the classroom. After that I observed how effective this program was through the interest arid attitude toward mathematics subject, learning accomplishment, and the change of self-directed learning. Finally, I wrote the conclusion and suggestion on the preparation of conditions fur the students' voluntary participation in mathematics learning and the project and application on 'the development of mathematical power' program and repeated learning with the materials of moving pictures in classroom.

• Korean Journal of Ecology and Environment
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• v.46 no.2
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• pp.145-153
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• 2013

It is a global trend that the water management policy is shifting from a water quality-oriented assessment to the aquatic ecosystem-based assessment. The majority of aquatic ecosystem assessment systems were developed solely based on physicochemical factors (e.g., water quality and bed structure) and a limited number of organisms (e.g., plankton and benthic organisms). Only a few systems use plants for a health assessment, although plants are sensitive indicators reflecting long-term disturbances and alterations in water regimes. The development of an assessment system is underway to evaluate and manage lakes as ecosystem units in the Korean Ministry of Environment. We reviewed the existing multivariate health assessment methods of other leading countries, and discussed their applicability to Korean lakes. The application of multivariate assessment methods is costly and time consuming, in addition to the correlation problem among variables. However, a single variable is not available at this moment, and the multivariate method is an appropriate system due to its multidimensional evaluation and cumulative data generation. We, therefore, discussed multivariate assessment methods in three steps: selecting metrics, scoring metrics and assessing indices. In the step of selecting metrics, the best available metrics are species-related variables, such as composition and abundance, as well as richness and diversity. Indicator species, such as sensitive species, are the most frequently used in other countries, but their system of classification in Korea is not yet complete. In terms of scoring metrics, the lack of reference lakes with little anthropogenic impact make this step difficult, and therefore, the use of relative scores among the investigated lakes is a suitable alternative. Overall, in spite of several limitations, the development of a plant-based multivariate assessment method in Korea is possible using mostly field research data. Later, it could be improved based on qualitative metrics on plant species, and with the emergence of further survey data.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.1
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• pp.27-41
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• 2016

This study was performed to investigate the community structure and health assessment of macrobenthic assemblages in Geoje-Hansan Bay, Southern Coast of Korea. Macrobenthos were collected by van Veen grab sampler at May (spring) and August (summer) 2013. The total species number and mean density were 300 species $7.6m^{-2}$ and $1,994ind.\;m^{-2}$, respectively. The major dominant species were the polychaetes Lumbrineris longifolia ($299{\pm}164ind.\;m^{-2}$), Aphelochaeta monilaris ($100{\pm}57ind.\;m^{-2}$), the bivalve Musculista senhousia ($91{\pm}96ind.\;m^{-2}$) and the polychaete Praxillella affinis ($80{\pm}66ind.\;m^{-2}$). From the community statistics [cluster analysis and nonmetric multidimentional scaling (NMDS) ordination], the macrobenthic community was distinguished into two groups of inner bay (farming ground of near Sandal Island) and channel station(from Hansan Island to Chubong Island) group. In this study, the ecological status was assessed by four biotic indices Shannon's H', the ATZI Marine Biotic Index (AMBI), multivariate-AMBI (M-AMBI) and the Environment Conservation Index (ECI). The ecological status of the macrobenthic community in Geoje-Hansan Bay were poorer in the inner bay station than in the channel station. The results of the present study showed that three biotic indices (Shannon's H', M-AMBI and ECI) were valid as an index for evaluating the ecological status than the AMBI.

• Horticultural Science & Technology
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• v.30 no.5
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• pp.586-595
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• 2012

This study was conducted to determine the effects of horticultural therapy (HT) program using hydroponics on work adjustment skills of students with mental retardation. Based on the critical role transitional model and special education curriculum for agriculture, especially hydroponics, HT program (total 22 sessions) using hydroponics procedure for Lettuce (Lactuca sativa L. 'Asia Heuk Romaine') was developed. Fourteen (10 males, 4 females) graded $1^{st}$ to $2^{nd}$ with intellectual disabilities were recruited from a special education class in a high school located in Inchon, Korea and then a special farm for hydroponics in Inchon, Korea was offered for the HT program. The students with intellectual disabilities participated in the HT program for 4-month (from September to December of 2011, twice a week, approximately 60 minutes per session). Before and after the HT program, the McCarron assessment neuromuscular development, emotional behavioral checklist, interpersonal negotiation strategies, and KEPAD picture vocational interest test were performed by the teachers and horticultural therapists. As the results, the students significantly improved motor performance (p = 0.002), emotional behavioral strategies (p = 0.00), and interpersonal negotiation strategies (p = 0.05). However, no significant difference between before and after the HT program for vocational interest was observed. In conclusion, the HT program using hydroponics, consists of simple and easy tasks so that it would be applicable for the students with intellectual disabilities positively affected to work adjustment skills by improving the motor performance, emotional behavioral strategies, and interpersonal negotiation strategies. Additionally, HT programs using hydroponics with various kinds of vegetables are required to develop and to apply in practical settings for improving work adjustment skills.

• Korean Journal of Ecology and Environment
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• v.41 no.3
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• pp.283-293
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• 2008

The objectives of the study were firstly to provide fundamental data for establishment of total maximum daily load (TMDL) management in Ulsan City, and secondly to make practical application of stream health assessment with tolerance range by each species when physiochemical and fish investigations were carried out together. A total of 44 sites in Taehwa River, Hoiya River, Dong Stream, and Cheongryang Stream were selected to monitor water qualities seasonally and fish investigation was performed in August 2006. Among the parameters of water quality, biological oxygen demand (BOD) and dissolved oxygen (DO) related to respiration, total nitrogen (T-N) and total phosphorus (T-P) related to nutrient and eutrophication, and total suspended solids (TSS) and $NH_4$-N were compared with vertical box plot by 8 dominant species. According to the fish investigation, 12 families 33 species were found including endangered species (Pungitius kaibarae) and introduced species (Lepomis macrochirus, Micropterus salmoides), and appearance rate of Korean endemic species was greater in Taehwa River (29.2%) than others. As the results of tolerance range by species, Zacco koreanus, Rhynchocypris oxycephalus, Iksookimia longicorpa, and Squalidus gracilis majimae had limited low range by water quality parameters indicating preference of good water quality. Whereas, Carassius auratus and Pseudorasbora parva were found downstream and urban-streams which were exposed from frequent inflow of pollutants. It concludes that the results help distinguishing sensitive, intermediate, and tolerant species when we evaluate stream health assessment with fish, and further making practical application for conservation and restoration of aquatic ecosystem.

• Korean Journal of Ecology and Environment
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• v.41 no.3
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• pp.402-411
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• 2008

Grazing effects of two freshwater shellfish, Unio douglasiae (UNIO) and Cipangoplaudina chinese malleata (CCM), on the hibernal diatom communities in eutrophic water was examined in a laboratory. Two animals having different feeding types used in the study were collected from Keum River (Boryeong, Korea), acclimatized in the artificial management system in a laboratory over at least one month, and starved in a laboratory for 2 days before the experiment. Experimental waters, which dominated by Synedra ulna-Scenedesmus sp. (ca. 80%), was collected from eutrophic lake, Lake Ilgam (Seoul) in Feb., 19, 2008 at AM 10:00, and used in the study after the filtration with 1 mm Nylon mesh. Feeding experiments were largely divided into three kinds of animal treatments; five densities of UNIO (U0, U1, U2, U3, U4) and CCM (C0, C1, C2, C3, C4), and four combined densities of two shellfish (M0, M1, M2, M3). U0 and C0 were control (no addition of UNIO or CCM), U1 or C1 (each animal density at 0.5 ind. $L^{-1}$), U2 or C2 (1.0 ind. $L^{-1}$), U3 or C3 (1.5 ind. $L^{-1}$), and U4 or C4 (2.0 ind. $L^{-1}$), respectively. Four combined treatments were consisted of M0 (no animals), M1 (U1+C3), M2 (U2+C2), and M3 (U4+C1), respectively. Under the presence of animal, the concentration of Chl-a and algal abundance were clearly decreased with the increase of UNIO density and the treated time, while in combined group a strong decrease of algal density showed with the increase of UNIO density. Total phytoplankton density shifted as the similar patterns to that of Chl-a concentration (r=0.6527, p<0.0001), however, there showed the differences following a species. There were strong decreases of dominant species Synedra ulna, Scenedesmus sp., Ankistrodesmus falcatus in UNIO treatment group, Diatoma vulgare in combined group, while Cryptomonas ovata in high density of CCM increased about 20% in algal density. Grazing rates (GRs) based on the concentration of Chl-a was depend on the kind of shellfish and treatment time; a strong feeding of CCM showed in the initial stage, and four hours later, UNIO and combined group with high UNIO density showed the high GRs. Interestingly, faeces production of shellfish was highest in combined group with high density of CCM, while their size over 60 ${\mu}m$ was much higher in production magnitude than that less 60 ${\mu}m$. Collectively, these results suggest that two domestic shellfish and its combined treatment have a strong potential as an effective biological controller of diatom bloom in cold eutrophic waters.

• Korean Journal of Environmental Biology
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• v.26 no.3
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• pp.159-169
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• 2008

This study was aimed to classify the intertidal macrozoobenthic community status after 2 years of Sea Prince oil spill, and oil spill effects along oil spreading track from heavily impacted to unaffected reference site. Field sampling was initiated in late February and continued through November 1998 seasonally, after 2.5 years of oil spill. 7 rocky sampling sites were selected among coastal regions coated and/or affected by the Sea Prince spilled oil. Identified species was 158 species, 65 family, 24 order, 9 class, 5 phylum. Mollusca was the dominant faunal group comprising 100 species (63.3%), and followed by 38 species of Crustacea (24.1%), 12 species of Echinodermata (7.6%), 5 species of Porifera (3.2%), and 3 species of Cnidaria (1.9%). On Dugpo of Sori Island, the fewest species was collected from 28 species to 35 species seasonally among sampling stations. But far away Dugpo toward Gamak Bay, the number of species increased, collecting the maximum on Sohwoenggan Island. At the wreck site of Sori Island, especially the species number of attached animals such as poriferans and anthozoans was very low compared to another site. The density and biomass on the higher tidal zone increased toward the low affected sites, but biomass on middle tidal zone decreased. The invertebrate biomass of study area was dependent on the sessile animals. The major dominant species were small-sized barnacles, Chthmallus challengeri, periwinkles, Littorina brevicula, mussels, Septifer virgatus, and so on. The biomass of C. challengeri and L. brevicula on the higher tidal zone was highest in the wreck site of Sori Island and decreased further and further. However, mussels on the middle tidal zone showed the inverse trends because of the larger individual size of mussel inhabited in Sori Island than those of another sites. As a result of community analysis, the effect of oil spill was not found distinctly. Several ecological indices and cluster analysis did not show the meaningful variation with oil track despite of the conspicuous differences among tidal heights. These indicate that the macrozoobenthic community level of oil spreaded zone recovered in some degree after the Sea Prince oil spill accident, but population or individual levels of dominant sessile animals took more recovery times.