• Korean Journal of Microbiology
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• v.39 no.4
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• pp.272-276
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• 2003

Sapgyo Lake is an artificial freshwater reservoir which is located to the midwest of Korea and is the main water reservoir for industry and agriculture of the region. In this study we investigated environmental factors and the change of bacterial community with the influence of surrounding inflow water and the seasonal variation using the molecular ecological approach. Water samples were collected at front of the dike in May and August, 2001. Bacterial genomic DNAs were extracted directly and purified for the amplification of bacterial 16S rDNA. Clone libraries of the 16S rDNA were constructed using pGEM-T easy vector and RFLP analysis was performed to make a group as OTUs with 4 base recognizing enzymes (MspI and HaeIII). The estimated values of richness in August sample was higher than in May. Thirty-three of 153 clones in May and thirty-eight of 131 clones in August were sequenced from forward region of bacterial 16S rDNA for about 600~800 bp. Proteobacteria, Cytophaga, gram positive bacteria and Verrucomicrobia were observed both months. Especially, Planctomyces, cyanobacteria and chloroplast appeared in August when algal bloom occurred. On the whole investigation, Sapgyo lake showed a typical community structure of estuarine and was influenced by heterochthonous organic matters from the surrounding stream.

• Korean Journal of Plant Resources
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• v.35 no.1
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• pp.29-35
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• 2022

Elsholtzia byeonsanensis is a Korean native plant of the Lamiaceae family, and was first introduced in the Korean Journal of Plant Taxonomy. This plant has a short plant length of 20-35 cm, with leathery and glossy leaves. The purple flowers bloom in November, so they are highly useful as potted or ground cover ornamental plants. In this study, tray cell size (128, 162, and 200-cell trays), soil composition [horticultural soil (HS): decomposed granite (DG) 1:1, 1:2, and 1:4 (v:v)], seeding rate (1, 2, and 3 seeds per cell) and additional fertilizer concentrations (0, 250, 500, and 1000 mg/L Hyponex) were tested to find out the optimum seedling growth conditions. As a result of the study, E. byeonsanensis growth increased proportionally as the cell size of the tray increased. The growth was inhibited as the percentage of DG increased. As for the growth according to the seeding rate, plant height, plant width, leaf length, and leaf width decreased as the seeding rate increased, but there was no difference in the number of leaves, stem diameter, and root length. There was an increasing trend in seedling growth as the additional fertilizer concentration increased. Therefore, for producing E. byeonsanensis seedling, it is most effective to fill HS or HS:DG 1:1 in 128-cell trays, sow one seed per cell, and spray the seedling at 1000 mg/L for additional fertilizer.

• The Journal of the Convergence on Culture Technology
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• v.9 no.4
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• pp.153-160
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• 2023

The process of verifying design concepts and ideas by producing real or equivalent model is essential in the product development process. Against this background, the purpose of this study is to consider the case of developing subjects that can systematically cultivate the ability to produce model from the basic stage to a certain level or higher, focusing on design engineering majors. As a theoretical consideration for this, prior studies related to making such as modeling or prototyping in related areas and majors such as industrial design are considered, followed by Bloom's revised taxonomy model and Hioshi Ishikawa's industrial design program as a methodological consideration for curriculum development. Finally, by applying this, we propose a new course that includes a lecture plan corresponding to the 16th week of learning, which is a general semester of university education. As a result of the study, it was confirmed that producing a physical model was still essential for the development of a new design, and accordingly, it was also necessary to establish a systematic curriculum suitable for the major area. Since the scope of this study extends to the development of subjects, in subsequent studies, it is necessary to consider the contents such as verification and reflection of the utility as competency education through actual application and suggestion of improved subject design.