• Journal of Bio-Environment Control
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• v.32 no.4
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• pp.319-327
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• 2023

To harvest marketable cucumbers, high quality seedlings must be used. Producing seedlings in the greenhouse during the low radiation period decreases marketability due to insufficient light for growth. Supplemental lighting with artificial light of different quality can be used to improve low light conditions and produce high quality seedlings. Therefore, this study was conducted to select the appropriate supplemental light sources on the growth and seedling quality of grafted cucumber seedlings during the low radiation period. Three cultivars of cucumber were used as scions for grafting; 'NakWonSeongcheongjang', 'Sinsedae', and 'Goodmorning baekdadagi'. Figleaf gourd (Cucurbita ficifolia) 'Heukjong' was used as the rootstock. The seeds were sown on January 26, 2023, and grafted on February 9, 2023. After graft-taking, cucumbers in plug trays were treated with RB light-emitting diodes (LED, red and blue LED, red:blue = 8:2), W LED (white LED, R:G:B = 5:3:2), and HPS (high-pressure sodium lamp), respectively. Non-treatment was used as the control. Supplemental lighting was applied 2 hours before sunrise and 2 hours after sunset for 19 days. The stem diameter and fresh and dry weights of roots did not differ significantly by supplemental light sources. The plant height and hypocotyl length were decreased in W LED. However, the leaf length, leaf width, leaf area, and fresh and dry weights of shoots were the highest in the RB LED. Seedling qualities such as crop growth rate, net assimilation rate, and compactness were also increased in RB LED and W LED. After transplanting, most of the growth was not significant, but early yield of cucumber was higher in LED than non-treatment. In conclusion, using RB LED, W LED for supplemental light source during low radiation period in grafted cucumber seedlings improved growth, seedling quality, and early yield of cucumber.

• Journal of Bio-Environment Control
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• v.32 no.4
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• pp.405-415
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• 2023

This study was conducted to investigate optimal conditions for cutting propagation of the strawberry cultivar "Sulhyang" through the collection methods of cuttings (runners tips), leaf number of cuttings, and cutting time. Cuttings were collected from the mother plant in the nursery bed (MP) and plants after fruit harvest (HP); the leaf number of cuttings was 0, 1, and 2, and the cutting time was at one-week intervals from June 4 to July 9. The survival rates for MP and HP cuttings were notably high, reaching 99.5% and 98.7%, respectively, but no significant difference was found. The number of roots were higher in MP cuttings, and there was no significant difference in crown and leaf growth. The fruit yields were 419.2 and 428.4 g, for MP and HP cuttings, respectively. The survival rates according to leaf number of cuttings were 98.1% and 98.3% for 1 and 2 remaining leaves, respectively, and remarkably lower at 25.3% for no remaining leaves. The root numbers were 26.0 and 26.3 for 1 and 2 remaining leaves, respectively, compared with 23.5 for no remaining leaves, with no significant differences in crown and leaf growth. The fruit yields were 424.4 and 421.5 g for 1 and 2 remaining leaves, respectively, and 396.7 g for no remaining leaves. The survival rates according to cutting time was over 97.2% in all cutting time without any difference in each treatment. The root, shoot, and crown of the nursery plant before planting showed the best growth in the cuttings on June 4 and 11, resulting in the highest fruit yields of 433.3 and 426.4 g, respectively, with the lowest yields at 384.5 g for cutting time on July 9. Both MP and HP materials proved suitable for strawberry cuttings. The optimal leaf number for cuttings was at least 1, and the optimal cutting time in Gyeongnam area was evaluated as around June 4-11.

• Journal of Bio-Environment Control
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• v.32 no.4
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• pp.257-266
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• 2023

This study was conducted to investigate the growth characteristics of cucumber (Cucumis sativus L. 'Joeunbaekdadagi') and tomato (Solanum lycopersicum L. 'Dotaerang Dia') seedlings by light intensities and CO₂ concentrations in a closed-type plant production system (CPPS). Cucumber and tomato seeds were sown in 50-cell trays and germinated in CPPS at air temperature 25 ± 1℃ and relative humidity 50 ± 10% for 4 days. After germination, the CO₂ concentrations and light intensity treatment were treated at 500 (ambient), 1,000, and 1,500 µmol·mol^-1 and 100, 200, and 300 µmol·m^-2·s^-1 photosynthetic photon flux density (PPFD), respectively. The leaf area of cucumber showed the highest value in CO₂ 1,500 μmol·mol^-1. However, the leaf area of the tomato had no significant difference in CO₂ concentrations and light intensities treatments. In cucumber and tomato both seedlings, the growth and quality such as compactness and leaf area rate were increased with the increase of light intensity, and there were highest in 300 µmol·m^-2·s^-1. The root surface and number of root tips of cucumber and tomato seedlings were significantly increased with the increase in light intensity. In conclusion, the regulation of the CO₂ concentrations and light intensity can control the growth and quality of cucumber and tomato seedlings in CPPS, especially, increasing the light intensity can improve more significantly the growth and quality of seedlings.

• Journal of Bio-Environment Control
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• v.33 no.1
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• pp.12-21
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• 2024

The aim of this research was to investigate the effect of gibberellin on improving seedling growth characteristics and enhancing strawberry quality in cutting propagation. Cuttings of the cultivar 'Seolhyang' were treated with GA₃ for 30 and 60 minutes at concentrations of 50, 100, and 150 mg·L^-1, with distilled water used for dipping as the control. Evaluation of seedling growth showed a positive correlation between the duration of gibberellin dipping and growth characteristics such as leaf number and SPAD value. Plant height, petiole length, leaf length and width, and leaf area varied significantly based on the interaction between dipping time and concentration. Crown diameter exhibited differences depending on the dipping time, with cuttings producing superior seedlings having a diameter of 8.0 mm or more for all treatments except the 30-minute, 100 mg·L^-1 treatment. The T/R ratio was significantly lower in the 30-minute, 50 mg·L^-1 treatment, indicating the highest plant vigor. Quantum yield was lower at a concentration of 150 mg·L^-1, showing a decreasing trend with increasing gibberellin concentration. Nonphotochemical quenching was significantly smaller in the 30-minute, 150 mg·L^-1 treatment, indicating an effective reduction of stress in the cuttings. Antioxidant content was highest in the 30-minute, 50 mg·L^-1 treatment and the 60-minute, 150 mg·L^-1 treatment. Moreover, the results of post-transplanting growth assessment showed no negative effect of gibberellin on flowering induction. Therefore, it was confirmed that gibberellin treatment during the cutting propagation of 'Seolhyang' strawberries had a positive effect on the production of high-quality seedlings. Dipping the cuttings in 50 mg·L^-1 gibberellin for 30 minutes is considered to be the most suitable method for improving growth and quality compared to the control.

• Journal of Bio-Environment Control
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• v.33 no.1
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• pp.22-29
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• 2024

This study was carried out to analyze the growth of grafted seedlings produced in a container-type farm system and a greenhouse to stably produce high-quality seedlings. For 14 days after graft-taking, the characteristics of korean melon grafted seedlings were compared by container farm and greenhouse. The container seedling system maintained a stable day/night temperature (25/20℃), relative humidity (70%), and light environment (PPFD 200µmol·m^-2·s^-1, photoperiod (16/8h). The difference between day and night temperature (DIF) was relatively large, with a mean temperature of 28.1/15.4℃ in the high-temperature greenhouse. Plant height of the korean melon seedling was longer in the greenhouse than in the closed seedling system, and the average SPAD value was 30.5 and 41.1 in the greenhouse and closed seedling system, respectively. To calculate the compactness of the graft seedlings, the shoot dry weight was divided by the plant height, and the value was 44.9±2.64 mg/cm and 24.4±1.56 mg/cm in the closed seedling system and the greenhouse treatment, respectively, 7 days after graft-taking. To produce high-quality seedlings during high-temperature or low-photo periods, it will be necessary to analyze the key factors that affect growth characteristics and transplanting growth and to verify the effects of the closed seedling system based on post-transplanting growth and yield.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.19 no.4
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• pp.231-241
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• 2024

Discovering innovative startups that use public technologies from universities and government-funded research institutes is crucial for maintaining national competitiveness. Advancing public R&D technology, discovering entrepreneurs from research institutes, and fostering and investing in deep-tech startups are very important at the national level. However, there is a lack of research on activating startups using public technologies, and research analyzing each governance entity is needed to activate the innovation startup ecosystem. Therefore, this study conducted an empirical analysis of the priorities for revitalizing the innovation startup ecosystem among researchers, research institutes, innovative startups, and the government, which constitute the public technology governance. The results of this study revealed that the sustainability of innovative startups (0.308), government innovation startup activation (0.298), research institutions discovering and fostering startups (0.221), and researcher's characteristics (0.173) were the most significant factors in the public R&D technology innovation startup ecosystem. And the sub-factors of researcher's characteristics, seizing business opportunities (0.305) was most important, and creating a startup-friendly culture (0.293) was most important among the sub-factors of research institutions discovering and fostering startups. Investment funds and procurement (0.373) was the most critical sub-factor for the sustainability of innovative startups, while a dedicated fund for public technology (0.305) was the most important among the sub-factors of government schemes for promoting innovative startups. A total of 20 factors were analyzed sequentially according to their importance in the weights for evaluation factors and sub-factors. By sub-factor, investment and financing for innovative startups (0.115), dedicated government fund for public technology (0.091), securing high-quality human resources for innovative startups (0.078), improving government regulations and permits related to innovative technologies (0.074), and creating a startup-friendly culture in research institutions (0.065) were the most important. This result emphasizes the significance of securing competitiveness to become a sustainable public technology startup. In addition, based on entrepreneurship experience, 'dedicated funding for public technology' was most important for the group with startup experience, while the group with no experience needed more 'investment and funding'. Furthermore, By region, 'improving government regulations and permits' was the highest priority in the Seoul metropolitan area, while 'attracting investment and financing' was the most important in Daejeon. Therefore, the results of this research, it is important to give policy priority to innovative startup companies in order to activate the innovation startup ecosystem in the public technology sector. The political and practical implications were derived that long-term (10 years or more) investment and funding for deep tech companies and the establishment of public technology-only funds are the most urgent and important.

• Microbiology and Biotechnology Letters
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• v.52 no.3
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• pp.255-263
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• 2024

In this study, antioxidant and anti-inflammatory activity was studied to confirm the value of kailan (Brassica oleracea L.) as a natural material for cosmetics. For this study measure the antioxidative activity, total polyphenol content was measured, and DPPH and ABTS scavenging activity assays were conducted. As a result of measuring the total polyphenol content of hot water extract of kailan (KRD) and 70% ethanol extract of kailan (KRE), it was found to contain 124.3 mg TAE/100 g and 144.1 mg TAE/100 g, respectively. As a result of DPPH and ABTS radical scavenging ability, it was confirmed that the efficacy was concentration dependent. After treating the cells with LPS, a stimulant, for 2 hours, an experiment was conducted by treating RAW 264.7 cells with KRD and KRE at concentrations of 10, 50, and 100 ㎍/ml. The nitric oxide production inhibitory activity of KRD and KRE showed an inhibitory effect of about 30% at a concentration of 100 ㎍/ml. Cells cultured for 18 hours after stimulant treatment were obtained and used in experiments. The cells obtained in this way were lysed, protein and mRNA were extracted, and the expression of inflammatory mediators' inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) was confirmed. It was confirmed that the protein mRNA expression of iNOS and COX-2, measured through western blot and reverse transcription-PCR, was inhibited in a concentration-dependent manner. Based on this, it is judged that has the potential to be used as a natural material in cosmetics.

• Journal of Korea Port Economic Association
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• v.40 no.3
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• pp.175-186
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• 2024

This study analyzes the changes in the coastal ferry transport network in South Korea due to the significant impact of the COVID-19 pandemic on the domestic shipping and logistics sector. Focusing on the small-sized ports network distributed across mainland and islands that make up the coastal ferry transport network, the research employs Social Network Analysis (SNA) methods to examine the structural changes and characteristics of the network from 2018 to 2021, distinguishing between the periods before and after the COVID-19 pandemic. By utilizing centrality indices such as the degree centrality, closeness centrality, and betweenness centrality, the study assesses the changes in the influence of small-sized ports within the network before and after the COVID-19 pandemic. The scope of this study focuses on Mokpo and Wando region in the Jellanamdo province, which have the largest coastal ferry transport networks and notable passenger transport performance in South Korea. It examines the primary ports in these regions and the small-sized ports located on the islands. Analysis of the Mokpo coastal ferry transport network indicates that the number of connected islands decreased before and after the pandemic, and connectivity to other islands within the network diminished. Factors such as the decline in tourist numbers due to COVID-19, the connecting with land bridges between the mainland and islands, and subsequent closure of ferry sea routes are believed to have impacted these network changes. In the Wando region, the sharp decrease in both island residents and tourists after the pandemic led to the suspension of ferry operations, resulting in disrupted connectivity with some small-sized ports on the coastal ferry transport network. This has affected network characteristics such as concentration and average path length in the Wando region. This study aims to analyze the changes in the domestic shipping and logistics, coastal ferry, network due to the COVID-19 pandemic, providing insights to predict potential network changes caused by uncertain events in the future and contributing to the formulation of proactive policies for effective responses.

• KOMUNHWA
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• no.93
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• pp.153-184
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• 2019

The Yunggimuntogi(Treasure No. 597) has been known to be recovered at Yeongseondong Shell Mounds, Busan in 1933 during the Japanese colonial period. This artifact is characterized by a short spout attached to one side of the mouth rim as well as a V-shaped clay stripe on the upper body part, which is the only earthenware designated as national cultural heritage from the prehistoric period. In order to prepare for the earthquakes that have recently become more frequent, this study has precisely diagnosed the conservation status and stabilized the artifact through scientific conservation treatment. As a result of the precise diagnosis of the preservation status, cracks and losses were observed in the spout, the mouth rim, and the base. In some portion of the raised pattern decorations, loss of fine pieces raised concerns over the secondary damage. The C·T image analysis has shown that the earthenware had been once glued and restored from dozens of broken pieces. From the sites restored in the past, the peeling of surface colored layer and the fine cracks between the restoration material and the earthenware clay were observed due to the aging of the restoration material. Furthermore, the inherent color and texture of the earthenware was altered by excessive color matching. The damaged and restored sites were concentrated on the left side, the rear side, and the right side. The damages were more severe on the base than the body portion. In the past, gypsum(CaSO4) had been mainly used as restoration material, and synthetic resin had been partially used for joining and reinforcing the pieces. On the surface of the restoration sites, it is presumed that lead chromate(PbCrO4) yellow modern pigment was used for color matching. The precise diagnosis has revealed that the restoration material in the past has been stabilized by interlocking with the earthenware clay for a long time. Therefore, in this conservation treatment, the coloring layer of the excessively painted surface was washed to recover the original color and texture of the earthenware, and the physically vulnerable parts of the sites restored in the past were mainly targeted for joining and restoration. The conservation treatment has proceeded in the order of cleaning, joining and restoration, and color matching, and materials and methods suitable for the artifacts were selected and applied through a preliminary experiment. The survey on conservation status before the treatment as well as the conservation treatment process have been systematically recorded and documented to provide basic data for further continuous conservation and maintenance by collecting institutions.

• Journal of Technologic Dentistry
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• v.10 no.1
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• pp.55-66
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• 1988

The great sudden change of circle of dental laboratory technology brought many discord between the new growing environmental group and the old group. In order to know the satisfactory degree of Dental Laboratory Heads about all and woman dental technicians who graduated from junior college, this study was conducted for 41 dental laboratory heads in Pusan area during Aug. to Sep. 1986 by means of a questionaire. The results are obtained as follows : 1. By born place, the dental laboratory heads’ satisfactory degree mean of items about all dental technician who graduated from junior college were Pusan group 3.55, Kyungnam group 2.94. The difference among the groups was significant enough(P<0.05). The satisfactory degree about woman dental technician graduated from junior college were Pusan group 3.45, Kyungnam group 2.72. 2. By age, The degree of satisfaction of items about all graduate dental technician were 30$\sim$34 age group 3.13, 40$\sim$44 age group 2.71. The degree of satisfaction about woman graduate dental technician were 30$\sim$34 age group 3.13, 40$\sim$44 age group 2.71. The degree of satisfaction about woman graduate dental technician were as follow : 35$\sim$39 age group 3.50, 45$\sim$49 age group 3.16, 30$\sim$34 age group 2.86, 40$\sim$44 age group 2.43. 3. By job career, the highest degree item out of satisfaction about all graduate dental technician was 6$\sim$10 years group 3.58, the other items were 1$\sim$15 years group 2.90, 16$\sim$20 years group 2.71. The satisfactory degree item about woman graduate dental technician was 6$\sim$10 years group 3.43, 16$\sim$20 years group 3.15, 11$\sim$15 years group 2.82 respectively. 4. By managing term of respondents’ dental laboratory, the satisfactory degree of items about all graduate dental technician were below 2 years group 3.25, 3$\sim$6 years group 3.14, 7$\sim$10 years group 2.93 in order. The satisfactory degree items about woman graduate dental technician were 11$\sim$14 years group 3.25, 3$\sim$6 years group 3.14 7$\sim$10 years group 2.80 in order. 5. By acquired qualification of licence test, the satisfactory degree of dental laboratory heads about all graduate dental technician were job career group 3.07, graduated from Dept. of Dental Technology group 3.00. The satisfactory degree about woman graduate dental technician were job career group 3.03 and graduated from Dept. of Dental Technology group 2.57. 6. By dental technician numbers of respondents’ dental laboratory. the satisfactory degree of items was as follow: 10$\sim$13 persons group is 2.86, 6$\sim$9 persons group 3.25, below 5 persons group 3.11. There was significant enough.(P<0.01). The satisfactory degree items about woman graduate dental technician were below 5 persons group is 3.00, 10$\sim$13 persons group 2.79, 6$\sim$9 persons group 2.67. 7. by the outlook of occupation, the satisfactory degree of dental laboratory heads about all dental technicians who graduated from junior college were neither good norbad group 3.20 bad group 2.59, good group 3.13. The difference among the groups was significant enough(P<0.01). The satisfactory degree about woman dental technicains graduated from junior college were good group 3.25, neither good nor bad group 2.80, bad group 2.75. The difference among the groups was significant enough.(P<0.01) 8. By occupational satisfaction, The satisfactory degree of items about all graduate dental technician were neither satisfied nor dissatisfied group 3.08, satisfied group 3.17, dissatisfied group 2.89. The satisfactional degree of items about woman graduate dental technician were satisfied group and neither satisfied mor dissatisfied group each 3.00 9. By the outlook of employment, the satisfactory degree of items about all graduate dental techician were bad group and neither good nor bad group 3.00. There was significant enough.(p<0.02) About woman graduate dental technician were good group 3.80, neither good nor bad group 3.00, bad group 2.84. The difference among the groups was significant enough.(P<0.01) 10. By cognition of the number of graduate dental technician, the satisfactory degree of dental laboratory heads about all graduate dantal technician were too many group 2.86, many group 3.32. There was significant enough.(P<0.05) About woman graduate dental techician were too many group 2.60, many group 3.20 The difference among the groups was significant enough.(P<0.01) 11. As compared with the items ut of satisfaction and improvement about all dental technician who graduated from junior college, the rate of satisfaction item was for as follow : dental technological theory is 5.21%, ability of adaptation and sincerity each 17.1%. The rate of improvement items was as follow : sincerity is 39%, ability of work and ability of basical work each 24.4%. 12. As compared with the items out of satisfaction and improvement about woman dental laboratory technician who graduated from junior college, the rate of satisfaction item was as follow : atmosphere of the office is 56.1%, sincerity 22%. The rate of improvement items was as follow : ability of adaptation is 36.6%, ability of work 31.7%.