• Journal of agriculture & life science
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• v.45 no.6
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• pp.73-80
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• 2011

To investigate the characteristics of plant growth and flower quality of gerbera 'Sunny Lemon' by amount of nutrient solution, young seedling plants, 'Sunny Lemon' were transplanted to rock-wool and medium of peat moss and perlite mixed with 1 to 2 and they were acclimatized in greenhouse during about 1 month. Nutrient solution supplied to the plants is sonneveld solution of 1/2 concentration and treatments launched June 24, 2010 when average plant height was $20{\pm}1cm$. Nutrient contents as a standard for starting point of irrigation by time domain reflectometry (TDR) were determined with 60-65%, 70-75%, and 80-85%. Results of growth during vegetative growth, plant height, leaf width and leaf number increased by 10% in rockwool, but they were not significantly different. As for plant growth depending on nutrient content, 80-85% treatment showed the highest values. Leaf number increased by 60%, and leaf width and plant height had a about 40% increase than initial growth. Effectiveness for flower quality, yield and days to flowering were superior when nutrient content of media was higher than in the others. Especially, average days to flowering in 80-85% content was advanced by 7-10 days compared to the day in 60-65% treatment. The total amount of nutrient supply per plant was higher in mixed medium than in rockwool, but change patterns of EC and pH were enhanced in rockwool. Based on our results, we recommended that growth, cut flower, and yield of gerbera 'Sunny Lemon' were more effective when nutrient content of mixed medium was maintained at 80-85%.

• Journal of the Korean earth science society
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• v.25 no.4
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• pp.242-250
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• 2004

The purpose of this study is to examine the interactive effects of teaching methods (expository and discovery) and learner's cognitive styles on the retention of learned content in Earth Science three weeks after an instruction is given. The subjects of this study were 1st graders of a boys' high school (n = 185) and co-educational high school (n = 189) in Gwangiu Metropolitan City of Korea. 92 students of the boys' high school and 95 students of the co-ed high school were assigned to the expository teaching group, and the rest of the boys' high school students and the co-ed high school students were to the discovery teaching group. The students were classified into field-independent learners, medium learners, and field-dependent learners based on their cognitive styles. The results of the study can be summarized as follows: First, the discovery teaching was more effective than expository teaching in terms of comprehension and application related to post-instruction retention of learned content. But there was no noticeable difference in knowledge domain. Second, the field-independent cognitive style was more effective than its counterpart, the field dependent cognitive style. Third, in the post-instruction retention test, not so much relevance was found between teaching methods and learner's cognitive style.

• Journal of the Korean earth science society
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• v.42 no.1
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• pp.88-101
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• 2021

The purpose of this study was to qualitatively examine the meaning of students' drawings in outdoor classes and modeling-based learning cycles. Ten students were observed in a gifted education center in Seoul. Under the theme of the Hantan River, three outdoor classes and three modeling activities were conducted. Data were collected to document all student activities during field trips and classroom modeling activities using simultaneous video and audio recording and observation notes made by the researcher and students. Please note it is unclear what this citation refers to. If it is the previous sentence it should be placed within that sentence's punctuation. Hatisaru (2020) Ddrawing typess were classified by modifying the representations in a learning context in geological field trips. We used deductive content analysis to describe the drawing characteristics, including students writing. The results suggest that students have symbolic images that consist of geologic concepts, visual images that describe topographical features, and affective images that express students' emotion domains. The characteristics were classified into explanation, generality, elaboration, evidence, coherence, and state-of-mind. The characteristics and drawing types are consecutive in the modeling-based learning cycle and reflect the students' positive attitude and cognitive scientific domain. Drawing is a useful tool for reflecting students' thoughts and opinions in both outdoor class and classroom modeling activities. This study provides implications for emphasizing the importance of drawing activities.

• Applied Chemistry for Engineering
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• v.10 no.1
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• pp.148-153
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• 1999

In situ composites containing a thermotropic liquid crystalline polymer were prepared by polycondensation of 1,4-bis(p-hydroxy-benzoyloxy)butane with 2-bromoterephthaloyl chloride in a poly(methyl methacrylate) solution. Morphology and mechanical, thermal properties of the composites were examined by differential scanning calorimeter(DSC), dynamic mechanical thermal analyser(DMTA), optical microscope and scanning electron microscope(SEM). The TLCP domains showed nematic phase. The glass transition temperature($T_g$) and mechanical properties of the PMMA in the composites increased with increasing the content of TLCP. The TLCP domains were finely dispersed in the PMMA matrix. The 20 wt % TLCP/PMMA composite prepared by in situ polymerization showed more improved mechanical property with finely well dispersed morphology compared with that prepared by solution blending of the same composition.

• Journal of the Korean Society for Library and Information Science
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• v.38 no.4
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• pp.85-104
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• 2004

This study is supposed to the way to add and enlarge the elements related to educational domain in metadata of school library information system (DLS) by using the concept of learning object which the education information service agencies have adapted. This study is to propose the methods which can be accessed according to the units of learning content in order that they can be applied to the teaching and learning situations, and describe and index the total traits of interior data elements included in the information resources. Thus, the metadata of the existing DLS through the additional elements : , , and was made to access the information resources according to the teaching and learning situations and to accept the concept of interior learning units by means of the element.

• Journal of the Korean Operations Research and Management Science Society
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• v.23 no.2
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• pp.131-156
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• 1998

Cooperative query answering is a research effort to develop a fault-tolerant and intelligent database system using the semantic knowledge base constructed from the underlying database. Such knowledge base has two aspects of usage. One is supporting the cooperative query answering Process for providing both an exact answer and neighborhood information relevant to a query. The other is supporting ongoing maintenance of the knowledge base for accommodating the changes in the knowledge content and database usage purpose. Existing studies have mostly focused on the cooperative query answering process but paid little attention on the dynamic knowledge base maintenance. This paper proposes a multi-level knowledge representation framework called Knowledge Abstraction Hierarchy (KAH) that can not only support cooperative query answering but also permit dynamic knowledge maintenance. The KAH consists of two types of knowledge abstraction hierarchies. The value abstraction hierarchy is constructed by abstract values that are hierarchically derived from specific data values in the underlying database on the basis of generalization and specialization relationships. The domain abstraction hierarchy is built on the various domains of the data values and incorporates the classification relationship between super-domains and sub-domains. On the basis of the KAH, a knowledge abstraction database is constructed on the relational data model and accommodates diverse knowledge maintenance needs and flexibly facilitates cooperative query answering. In terms of the knowledge maintenance, database operations are discussed for the cases where either the internal contents for a given KAH change or the structures of the KAH itself change. In terms of cooperative query answering, database operations are discussed for both the generalization and specialization Processes, and the conceptual query handling. A prototype system has been implemented at KAIST that demonstrates the usefulness of KAH in ordinary database application systems.

• Journal of Science Education
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• v.44 no.1
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• pp.38-49
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• 2020

The purpose of this study is to analyze the paper test items of high school physics I 'Space-Time and the Universe' unit and how similar the textbook goals are to the cognitive and content areas. This study analyzed paper test items used from nine high schools and KICE about the unit. In order to analyze the distribution of items, they were classified by contents and by cognitive level which is knowledge, comprehension and application levels. As conclusion, application level items were a few, and unbalanced contents distribution appeared in school items. In comparison through the ratio difference index, the objectives of the textbook and the school items were very similar, but the similarities were low when comparing the school items with the KICE items. Based on the above, we suggested some ways to increase the validity of test items.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.6
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• pp.683-688
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• 2018

In the 21stcentury, teachers must welcome new technology to ensure the best learning in virtual classrooms, aside from the physical classroom. Google Classroom provides a vital chance to promote blended learning and professional development. The purpose of this study is to specify the procedures in problem design when employing blended problem-based learning (BPBL) and to design problems for learning the contents of the subject. The design of problems is crucial for effective BPBL. The underlying theory of BPBL is that learning is most effectively initiated and facilitated by posing and solving real-life problems that interest the learner, because working on such problems makes learning meaningful and motivates students. Ineffective problem-based learning (PBL) could affect students when acquiring sufficient domain knowledge, activating appropriate prior knowledge, and properly directing their own learning. The procedures for designing good problems are composed of the selection of educational content, figuring out the learner's characteristics, finding problems, setting up roles and situations, and writing down problems. Using these procedures, we designed five integration problems covering the contents of management subjects. Planned management subjects based on BPBL in a Mongolian university focuses on the process of designing problems.

• Journal of Korean Academy of Nursing
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• v.46 no.2
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• pp.293-304
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• 2016

Purpose: This methodological study was conducted to develop and psychometrically test the Transcultural Self-efficacy scale (TCSE-scale) for nurses. Methods: Initial 41 items for the TCSE-scale were generated based on extensive literature reviews and in-depth interviews with 18 nurses who had experience in caring for foreign patients. Cultural Competence and Confidence model was used as a conceptual framework. Content validity was evaluated by an expert panel. Psychometric testing was performed with a convenience sample of 242 nurses recruited from four general hospitals in the Seoul metropolitan area and Gyeonggi-do province of South Korea. To evaluate the reliability of TCSE-scale, a test-retest reliability and an internal consistency reliability were analyzed. Construct validity, concurrent validity, criterion validity, convergent validity and discriminative validity were used to evaluate the validity. Results: The 25-item TCSE-scale was found to have three subscales-Cognitive, Practical, and Affective domain-explaining 91.5% of the total variance. TCSE-scale also demonstrated a concurrent validity with the Cultural Competence Scale. Criterion-related validity was supported by known-group comparison. Reliability analysis showed an acceptable-to-high Cronbach's alpha-.88 in total, and subscales ranged from .76 to .87. The ICC was .90, indicating that the TCSE-scale has internal consistency and stability of reliability. Conclusion: This preliminary evaluation of the psychometric scale properties demonstrated an acceptable validity and reliability. The TCSE-scale is able to contribute to building up empirical and evidence based on data collection regarding the transcultural self-efficacy of clinical nurses. We suggest further testing of the applicability of TCSE-scale in different settings and community contexts.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.45 no.5
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• pp.32-37
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• 2008

To ensure access to rapidly growing video collection, video indexing is becoming more and more important. In this paper, video ontology system for retrieving a video data based on a scene unit is proposed. The proposed system creates a semantic scene as a basic unit of video retrieval, and limits a domain of retrieval through a subject of that scene. The content of semantic scene is defined using the relationship between object and event included in the key frame of shots. The semantic gap between the low level feature and the high level feature is solved through the scene ontology to ensure the semantic-based retrieval.