• Horticultural Science & Technology
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• v.19 no.1
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• pp.71-77
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• 2001

Experiments were conducted to evaluate quality and vase life of cut rose 'Rote Rose' cultivated in soil or hydroponically in rockwool. Rose flower stems harvested in commercial greenhouses in Kimhae on May 27 and June 14, 1998 were transported for about two hours to a laboratory and recut in water to an uniform stem length of 45cm. The rose flowers harvested on the same day were displayed at a density of $10cm{\times}10cm$ and were subjected to the same environmental conditions in a growth chamber. The stems were put in four different preservative solutions, 0.5% Chrysal RVB, BS (2% sucrose+200ppm 8HQS+0.3% Chrysal RVB), Sonk1 (BS+0.1mM ethionine), and double distilled $H_2O$. Flower stems harvested on May 27 were displayed at $18{\pm}1^{\circ}C$, RH 60-70%, and light intensity of 220lux provided by fluorescent lamps for $16h{\cdot}d^{-1}$. Flower stems harvested on June 14 were displayed at $25{\pm}1^{\circ}C$, RH 70-80%, and light intensity of 220lux provided by fluorescent lamps for $16h{\cdot}d^{-1}$. Fresh weight and flower diameter were affected by cultivation method, and were greater in hydroponically-grown roses than in soil-grown roses. Among the preservative solutions, BS and Sonk1 were superior to Chrysal RVB in terms of prolonging vase life. Vase life extension in Chrysal RVB, BS and Sonk1 over the control was about one day in both display temperatures. At $18^{\circ}C$ vase life was maintained for three to four additional days as compared to that at $25^{\circ}C$.

• Fire Science and Engineering
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• v.18 no.2
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• pp.20-26
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• 2004

The purpose of this study is to investigate the transition mechanism and prevention mechanism of gas explosion to fire. Transition phenomena of explosion to fire of LPG in the explosion vessel of its size of TEX>$100 cm {\times} 60 cm {\times} 45 cm$ was visualized using the high speed video camera and the mechanism was analysed from the videograph. Newspaper size of $30cm {\times} 20cm$ was used for combustible sample in this experiments and LPG-air mixture was ignited by 10 ㎸ electric spark. Experimental parameter was gas concentration, size of vent area and position of combustible solid. Size of vent area were varied as $10cm {\times} 9cm, 13cm {\times} 10cm, 27cm {\times} 20cm, 40cm {\times} 27cm$, and the position of combustible was varied in 4 point. Carbon dioxide was used to study the prevention mechanism of explosion to fire transition of LPG. Based on this experiment we can find that transition possibility of explosion to fire on solid combustible from explosion is depends on concentration of LPG-air mixture and the exposure time of solid combustibles in high temperature atmosphere of flame and burnt gas. And cooling or inerting of the atmosphere after explosion can be prevent the transition of explosion to fire on solid combustibles from gas explosion.

• Review of Culture and Economy
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• v.19 no.2
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• pp.29-50
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• 2016

This paper is to apply an individual travel cost method(TCM) to estimate demand functions for cultural services enjoyed by visiting 3 branches of the National Museum of Modern and Contemporary Art located in the Seoul Metropolitan area. This paper extends the standard TCM by incorporating opportunity costs of leisure time and two different data generating process - 398 respondents from an on-site survey and 600 respondents from a general household survey. Negative binomial models reflecting the non-negative integer nature of visiting frequency with over-dispersed variance were best fitted for demand functions, in which residents of Seoul metropolitan area surveyed from on the site exhibited higher visitation demand for the national art museum. Price elasticity and income elasticity differed by respondents' residency. Price elasticity of long distance visitors (-0.21) was more inelastic from those of Seoul residents (-0.34 ~ -0.5). Moreover, regional residents outside of Seoul area seemed to consider that services from the national art museum is a normal good with income elasticity of 0.5, whereas the Seoul residents seemed to perceive it to be an inferior good with income elasticity of -0.05.

• Journal of Bio-Environment Control
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• v.31 no.2
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• pp.98-103
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• 2022

Non-destructive estimation of leaf area is a more efficient and convenient method than leaf excision. Thus, several models predicting leaf area have been developed for various horticultural crops. However, there are limited studies on estimating the leaf area of strawberry plants. In this study, we predicted the leaf areas via nonlinear regression analysis using the leaf lengths and widths of three-compound leaves in five domestic strawberry cultivars ('Arihyang', 'Jukhyang', 'Keumsil', 'Maehyang', and 'Seollhyang'). The coefficient of determination (R²) between the actual and estimated leaf areas varied from 0.923 to 0.973. The R² value varied for each cultivar; thus, leaf area estimation models must be developed for each cultivar. The leaf areas of the three cultivars 'Jukhyang', 'Seolhyang', and 'Maehyang' could be non-destructively predicted using the model developed in this study, as they had R² values over 0.96. The cultivars 'Arihyang' and 'Geumsil' had slightly low R² values, 0.938 and 0.923, respectively. The leaf area estimation model for each cultivar was coded in Python and is provided in this manuscript. The estimation models developed in this study could be used extensively in other strawberry-related studies.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.2
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• pp.363-368
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• 2021

Ship engine rooms have improved automation systems owing to the advancement of technology. However, there are many variables at sea, such as wind, waves, vibration, and equipment aging, which cause loosening, cutting, and leakage, which are not measured by automated systems. There are cases in which only one engineer is available for patrolling. This entails many risk factors in the engine room, where rotating equipment is operating at high temperature and high pressure. When the engineer patrols, he uses his five senses, with particular high dependence on vision. We hereby present a preliminary study to implement an engine-room patrol robot that detects and informs the machine room while a robot patrols the engine room. Images of ship engine-room equipment were classified using a convolutional neural network (CNN). After constructing the image dataset of the ship engine room, the network was trained with a pre-trained CNN model. Classification performance of the trained model showed high reproducibility. Images were visualized with a class activation map. Although it cannot be generalized because the amount of data was limited, it is thought that if the data of each ship were learned through transfer learning, a model suitable for the characteristics of each ship could be constructed with little time and cost expenditure.

• Journal of Life Science
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• v.33 no.1
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• pp.8-14
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• 2023

Peroxidasin (PXDN), a multidomain heme peroxidase containing extracellular matrix (ECM) motifs, as well as a catalytic domain, catalyzes the sulfilimine crosslink of collagen IV (Col IV) to reinforce Col IV scaffolds. We previously reported that PXDN is required for endothelial cell (EC) survival and growth signaling through sulfilimine crosslink-dependent matrix assembly. In this study, we examined whether peroxidase activity is required for PXDN function in ECs. First, we constructed a mutant PXDN by point mutation of two highly conserved amino acids, Q823 and D826, which are present in the active site of the peroxidase domain. After isolation of HEK293 clones highly expressing the mutant protein, conditioned medium (CM) was obtained after incubating the cells in serum-free medium for 24 hours and then analyzed by Western blot analysis under nonreducing conditions. The results revealed that the mutant PXDN formed a trimer and that it was cleaved by proprotein convertase-like wild-type (WT) PXDN. However, peroxidase activity was not detected in the CM containing the mutant PXDN, in contrast to that of WT PXDN. In addition, the sulfilimine crosslink ability of the mutant PXDN was lost. Moreover, the CM containing the mutant PXDN failed to promote the growth of PXDN-depleted ECs, unlike the CM containing WT PXDN. These results suggest that the peroxidase activity of PXDN affects EC growth by forming a sulfilimine crosslink.

• Korean Journal of Construction Engineering and Management
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• v.24 no.5
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• pp.52-62
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• 2023

The objective of this study is to propose an automated algorithm for precise cutting length of slab rebar complying with regulations such as anchorage length, standard hooks, and lapping length. This algorithm aims to improve the traditional manual quantity take-off process typically outsourced by external contractors. By providing accurate rebar quantity data at BBS(Bar Bending Schedule) level from the bidding phase, uncertainty in quantity take-off can be eliminated and reliance on out-sourcing reduced. In addition, the algorithm allows for early determination of precise quantities, enabling construction firms to preapre competitive and optimized bids, leading to increased profit margins during contract negotiations. The proposed algorithm not only streamlines redundant tasks across various processes, including estimating, budgeting, and BBS generation but also offers flexibility in handling post-contract structural drawing changes. In particular, the proposed algorithm, when combined with BIM, can solve the technical problems of using BIM in the early phases of construction, and the algorithm's formulas and shape codes that built as REVIT-based family files, can help saving time and manpower.

• Research in Plant Disease
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• v.30 no.2
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• pp.194-198
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• 2024

Pathogens of fire blight can survive for a long time on pruning tools, etc., and fire blight can be spread through agricultural implements. In particular, in Korea, pruning is frequently performed to remove flowers, immature fruits, and succulent shoots, and this farm work is known to be a major factor of the spread of fire blight. Therefore, in this study, in order to completely sterilize pathogens on pruning shears, we verified the disinfection effect of disinfectants distributed domestically and used them to identify an effective disinfection method. When disinfecting by immersion after inoculating Erwinia amylovora TS3128 on the scissor blade, 70% ethanol and 1% and 0.2% sodium hypochlorite sterilized immediately 10 sec after immersion, while 30% chlorine dioxide showed little disinfection effect. When disinfecting by spraying, 70% ethanol sterilized bacteria 1 sec after spraying, but 1% and 0.2% sodium hypochlorite disinfected bacteria after 10 and 60 sec, respectively. After cutting the naturally disease occurring branches five and 100 times, the bacteria were not hardly sterilized in immersion treatment in 70% ethanol for 30 sec but perfectly disinfected over 60 sec. Considering these results, pruning shears should be disinfected by frequently immersing them in 70% ethanol for at least 60 sec during pruning work in the field.

• Journal of the Korean Applied Science and Technology
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• v.41 no.2
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• pp.292-304
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• 2024

This study compared and evaluated the antioxidant activities of Symphoricarpos albus(S. albus) extract and fermented extract. Antioxidant activity was measured by DPPH radical scavenging, FRAP, and ABTS. Concentrations were measured at 200, 100, 50, and 10 ㎍/mL, and antioxidant activity increased in a concentration-dependent manner. S. albus leaves fermented extracts had the highest antioxidant activity. And this study evaluated the safety and tail regeneration of S. albus extract using zebrafish model embryos. Zebrafish are in the spotlight as an alternative animal and can be used for cosmetic research. Zebrafish embryos were collected and evaluated for coagulation rate, hatching rate, and cardiotoxicity. As a result, it was toxic at concentrations above 100 ㎍/ml. The tail was cut and the regenerative effect was observed for 3 days. As a result, from 72 hours, S. albus 200ug/ml leaf extract showed a 17% regenerative effect compared to the control group. These results suggest that S. albus can be used as a natural material for antioxidant and regeneration for skin improvement.

• Horticultural Science & Technology
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• v.33 no.6
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• pp.883-890
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• 2015

The soilborne fungus Fusarium oxysporum f. sp. lilii (Fol) is a serious threat to all lily cultivars, especially infecting bulbs and flowers. It has become increasingly important to develop varieties resistant against the bulb rot disease. Genetic diversity of cultivars and reliable screening methods are required for this purpose. Here, an efficient in vitro screening system for evaluating resistance to Fol in 38 in vitro-grown lily plants was investigated. Various factors including culture conditions of Fol, inoculum density, appropriate plant materials, inoculation method and duration, and incubation period of plant materials after inoculation were combined to optimize the screening method. As a result, we suggest optimal conditions for an in vitro screening system for the selection of Fol-resistant lily cultivars as follows. Fol was grown on potato dextrose agar (PDA) medium for 6 days at $25^{\circ}C$ in darkness and used as working inoculation. Spore suspensions were prepared (inoculum density: $1.0{\times}10^4$ $spores{\cdot}mL^{-1}$), and then leaf segments $1.5{\times}2.0cm^2$ were inoculated by dipping for 22 hours at $25^{\circ}C$ in dark. Later, leaves were cultured on 0.6% agar plates at $25^{\circ}C$ and 50% humidity with a photoperiod of 16 hours light/8 hours dark (fluence rate of $40{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) to examine the progress of bulb rot. After 7 days, disease levels were classified into indices 1 (no symptom) to 6 (serious bulb rot). Soil inoculation of Fol carried out with resistant or susceptible lily cultivars that had been selected through in vitro screening confirmed the reproducibility of results. Therefore, the in vitro screening method established in this study is efficient and reliable for selection of lily cultivars resistant against bulb rot disease.