• Journal of Bio-Environment Control
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• v.6 no.1
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• pp.34-42
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• 1997

Effects of DIF on stem elongation in plug seedlings of mini tomato ‘Mini Carol’ and on the growth and flowering after transplanting were investigated. Stem elongation of seedlings was mainly influenced by day temperature rather than night temperature. When the effect of ＋DIF was compared to that of -DIF under the same average daily temperature(ADT), day temperature had greater impact on internode elongation than night temperature. On the other hand, leaf unfolding rate increased and compactness decreased as ADT in creased. Differences in internode length affected by DIF during seedlings stage DIF progressively diminished during growth period after transplanting. Node position at which first flower was initiated was lowered as ADT decreased. It was concluded that DIF treatment was an applicable tool for control of stem elongation, particularly to reduce stem length without a noticeably adverse effect on the growth and development of plant after transplanting.

• Journal of Bio-Environment Control
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• v.12 no.1
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• pp.22-25
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• 2003

Seedlings of ‘Nokgwang’ and ‘Kwari’ green pepper were cultured in 32-cell plug trays in TK$_2$ medium to find out optimal concentrations of phosphate. Seedling growth of both ‘Nokgwang’ and ‘Kwari’ cultivars was affected by phosphate strength. Applying P fertilizer to the plug system caused a marked increase in plant height and leaf area at 1.0 phosphate strength. On the other hand, total dry weight increased with increasing phosphate strength. Higher chlorophyll content was observed in ‘Nokgwang’ than ‘Kwari’ in all treatments. Phosphate strength greater than 0.5 gave similar chlorophyll content. Photosynthetic rate was higher for plants fertilized with 1.0 strength for ‘Nokgwang’ and 0.5 strength for ‘Kwari’than the other treatments. Higher concentrations of phosphate reduced photosynthesis in both cultivars. With ‘Nokgwang’increasing concentration of phosphate up to 1.0 strength resulted in increase in stomatal conductance and transpiration rate.

• Journal of Bio-Environment Control
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• v.12 no.1
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• pp.26-29
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• 2003

Experiments were conducted to estimate optimal potassium strength in the nutrient solution for ‘Nokgwang’and‘Kwari’green pepper seedlings cultured in small plug-cell trays. Plant height, stem diameter, and leaf area increased with increasing K concentration, with greater effect on ‘Kwari’ than ‘Nokgwang’. Total dry weight increased by increasing potassium strength.‘Kwari’had heavier dry weight than ‘Nokgwang’Chlorophyll content differed by cultivars and potassium strength. The highest chlorophyll content was obtained at 2.0 strength potassium in‘Nokgwang’, but not in‘Kwari’Net photosynthesis was greater in plants fertilized with 1.5 strength potassium for‘Nokgwang’and 2.0 strength potassium for ‘Kwari’than the other treatments.

• FLOWER RESEARCH JOURNAL
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• v.17 no.4
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• pp.256-261
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• 2009

This study was carried out to examine the effects of cutting condition on the rooting and their subsequent growth of cut flower in plug cutting of summer-flowering chrysanthemum 'Iwanohakusen'. The more leaves were attached to the cutting, the higher shoot growth and rooting were. Shoot growth of cuttings was not affected by cutting length, but rooting was better in over 5 cm long cutting. Shoot growth was enhanced by increasing thickness of cutting, and 5.5 mm thick cutting was favored in rooting. When the many leaves were attached on the cutting, the length and weight of cut flower increased. Over 7 cm long cutting showed higher values in growth of cut flower and ray flower number. Cutting of 5.5 mm diameter showed more favorable growth of cut flower than the other treatments. Therefore, it is concluded that rooting of cutting and consecutive growth of cut flower was improved when 7 cm long and 5.5 mm diameter cutting with 4 leaves was used in plug cutting of chrysanthemum 'Iwanohakusen'.

• Journal of the Korean Society of Earth Science Education
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• v.14 no.2
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• pp.80-94
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• 2021

In this study, teaching-learning activities were developed based on computational thinking (CT) in high school Earth Science I Solid Earth domain. And their effects and implications were examined. To this end, 8 sessions unplugged activities based on problem solving were developed, and applied it to 65 high school students. As a results, significant changes have been were confirmed in both student's perception about CT and CT. After that, based on student's responses to self-reports and interview, the affecting factors for perception about CT and CT in the earth science problem solving process were investigated. In addition, implication that should be considered in terms of design and progress of teaching-learning based on CT were derived. Based on these results, the necessity and operation of teaching-learning activities was suggested for developing CT through various subjects including earth science.

• Journal of The Korean Association of Information Education
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• v.23 no.1
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• pp.9-18
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• 2019

In this study, the contents of the Software Education area included in the Practical Art textbooks of the elementary school were analyzed based on the achievement standards of the Software Education in the 2015 revised curriculum for exploring the characteristics of the Software Education and the direction to go. According to the results of the analysis, the five achievement standards presented by the Ministry of Education were assigned to 17 or 18 times according to the textbooks. Unplugged activities related to Algorithm and unplugged activities related to Computer Science were included in textbooks. Contents of [6P04-09] and [6P04-10] standards were shown differently according to textbooks.Based on the results, it is suggested that Subsequent studies with quantitative and qualitative analysis for six kinds of textbooks should be continue.

• Journal of The Korean Association of Information Education
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• v.25 no.6
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• pp.987-994
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• 2021

Computational Thinking is an analytical thinking ability that is necessary for everyone and everywhere. The existing Computational Thinking development education provided in Practical textbooks leads to block-based programming languages from unplugged activities. Many unplugged activities focus on practicing sequential order, which may lack the learning of abstractions or automation concepts. In block-based programming languages, concepts such as coordinate planes, which are not introduced in elementary school curriculum, appear, making students feel burdened by the block-based programming language itself. In this study, a curriculum was designed for elementary student's computational thinking through game-based programming language education. The results and their effectiveness were analyzed through the beaver challenge. As a result of analyzing the pre-test and post-test scores, it was confirmed that students' computational thinking skills improved.

• Journal of Software Assessment and Valuation
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• v.13 no.2
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• pp.9-17
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• 2017

Software compliance is an essential process when Open Source Software is included in software development to avoid such as license violation issue. However, analyzing quite big software which involves many developers requires enormous time and hard difficulty. To resolve these kinds of problem, SPDX formalizes and standardize the metadata about the software package. When the use of SPDX is activated, software package analysis would be simple and could contribute fair Open Source Software distribution. In this paper, we develop blockchain based SPDX distribution platform which fulfills the requirement of SPDX lifecycle to provide SPDX database which does not depend on particular centralized service but serve as distributed ledger and control by user's certification and their purpose. Moreover, to contribute invigoration of blockchain based SPDX distribution platform, we develop SPDX document generation plug-in for integrated development environment such as Visual Studio.

• The Journal of the Convergence on Culture Technology
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• v.10 no.1
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• pp.495-500
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• 2024

The purpose of this study is to evaluate the accessibility of the SI-Bass Guitar for the visually impaired who uses the Sense Reader which is a screen reader software. An evaluation was performed for the Sense Reader users to do the [Virtual Instrument Editing] task on the NCS(National Competency Standards) using the SI-Bass Guitar. This study shows that the SI-Bass Guitar has no basic accessibility. But the visually impaired can do above task using the Sense Reader's Mouse Pointer and Position Memory Function. Several Propositions are suggested to develop a fully accessible SI-Bass Guitar for the screen users.

• Horticultural Science & Technology
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• v.34 no.5
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• pp.727-735
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• 2016

This research was conducted to investigate the influence of various pre-planting $NO_3:NH_4$ ratios in the coir dust+peatmoss+perlite (3.5:3.5:3, v/v/v) medium on the growth of tomato plug seedlings (cv. Dotaerang Dia), changes in chemical properties of root media, and tissue nutrient contents. With the fixation of N concentration to $300mg{\cdot}L^{-1}$, the $NO_3:NH_4$ ratios were adjusted to 100:0, 73:27, 50:50, 27:73, 0:100. Then, root media containing various $NO_3:NH_4$ ratios and equal concentration of other essential nutrients were filled into 50-cell plug trays and the seeds of 'Dotaerang Die' tomato were sown. The investigation of seedling growth and tissue analysis for mineral nutrient contents based on the dry weight of above-ground tissue were conducted 6 weeks after sowing. As seedlings grew, the EC decreased quickly and pH increased gradually in the all treatment media. The plant height, fresh weight and dry weight of seedlings in the treatment of 50:50 ($NO_3:NH_4$) were 29.0 cm, 13.7 g, and 1.21 g, respectively, which were the highest among treatments tested. However, the seedlings in the treatment of 0:100 ($NO_3:NH_4$) had 26.5 cm, 11.2 g, and 0.92 g in plant height, fresh weight and dry weight, respectively. These were the poorest among the treatments tested. The tissue contents of N were 2.77 to 3.22% in all the treatments. The treatment of 27:73 ($NO_3:NH_4$) had the highest contents of Fe, Mn and Zn and that of 0:100 ($NO_3:NH_4$) had the lowest contents of Mg, Na, Cu, Mn and Zn among the treatments tested. The results indicate that $NH_4$ ratio should be lower than 50% in the coir dust+peatmoss+perlite (3.5:3.5:3, v/v/v) medium for seedling growth of tomato and the optimum ratio will be used to draw up guide lines for plug seedling production.