• Journal of Life Science
• /
• v.10 no.6
• /
• pp.591-597
• /
• 2000

An investigation was conducted to elucidate the effect of sucrose, germicides and abscisic acid (ABA) in the preservatives on postharvest quality, such as fresh weight, solution uptake, vase life, diameter and thickness of flower, and chlorolhyll of leaf in cut chrysanthemum 'Kyoungsubang`. Fresh weight of cut chrysanthemum was highest in 250mg/L aluminum sulfate [{TEX}$Al_{2}(SO_{4})_{3}${/TEX}]+3% sucrose and 250 mg/L 8-hydroxyquinoline sulfate (8-HQS)+ 3% sucrose. Addition of sucrose and germicides inhibited microorganisms growth in solution, and apparently promoted solution uptake. The increased fresh weight seems to attribute to the elevated uptake. Germicide 8-HQS was more effective than {TEX}$Al_{2}(SO_{4})_{3}${/TEX} in the aspect of solution uptake and fresh weight. Treatment of 250 mg/L 8-HQS +3% sucrose showed the longest vase life (24.67±2.52 days) and the lowest rate of leaf chlorosis (or senescence). Addition of {TEX}$Al_{2}(SO_{4})_{3}${/TEX} and sucrose accelerated leaf chlorosis and increased diameter of flower, respectively. Sucrose treatment prolonged the vase life of flowers. Except control and 250 mg/L 8-HQS, content of chlorophyll was rapidly decreased after 6 days at upper, middle and lower leaves in order.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1997.04a
• /
• pp.900-904
• /
• 1997

A problem in the grinding process using the machining center(MC) with a small diametric wheel is the machining error due to due to decrease of quill diameter. In this paper, a side-cut grinding is performed with a vitrified bonded CBN wheel by the MC, and the relation between grinding force and machining error for grinding conditions is investigated experimentally. It is show that the normal force has a significant effect on the machining error.

• Horticultural Science & Technology
• /
• v.30 no.6
• /
• pp.718-724
• /
• 2012

Sugars play important roles in petal senescence of cut flowers. In the Expt. 1 of this study, the effects of different concentrations of glucose (60, 90, and $120g{\cdot}L^{-1}$) and sucrose (30, 60, and $90g{\cdot}L^{-1}$) application on the vase life, rate of flower diameter increase, rate of flower weight increase and ethylene production of cut tree peony (Paeonia suffruticosa 'Luoyang Hong') were evaluated. At the earlier stage, treatments of different concentrations of glucose and sucrose all retarded the process of flower opening and inhibited the increase of flower diameter and weight, while senescence of flowers fed with different concentrations of glucose was delayed at later stage. Flowers treated with $90g{\cdot}L^{-1}$ glucose displayed the longest vase life, which showed significant difference (P < 0.05) from those of flowers with the control and sucrose treatments. All treatments with glucose or sucrose not only retarded the decrease of flower diameter and weight, but also suppressed the ethylene production at the earlier stage and delayed the peak of ethylene evolution. In order to study the effect of exogenous sugar on the postharvest response of cut tree peony to ethylene, Expt. 2 was conducted. Cut flowers were treated with $90g{\cdot}L^{-1}$ glucose for 4 hours before (GE) or after (EG) exposed to $10{\mu}L{\cdot}L^{-1}$ ethylene for 4 hours. Generally, the opening process of flowers with GE and EG treatments was similar to that of the control, however GE treatment delayed flower senescence. Both GE and EG treatments improved flower diameter and weight, and GE treatment delayed the time of flower weight decrease. Besides, GE delayed climacteric ethylene evolution for 8 hours. All above suggest that exogenous sugars delay tree peony 'Luoyang Hong' cut flower senescence and extend flower vase life through their roles in the decrease of water loss and the suppression of sensitivity to ethylene and ethylene production.

• Journal of Biosystems Engineering
• /
• v.28 no.3
• /
• pp.231-238
• /
• 2003

Rose and chrysanthemum are the most popular flowers in Korean floriculture. Sorting flowers is a labor intensive operation in cultivation of the cut flowers and needed to be mechanized. Machine vision is one of the promising solutions for this purpose. This study was carried out to develop hardware and software of a cut flower sorting system using machine vision and to test its performance. Results of this study were summarized as following; 1. Length of the cut flower measured by the machine vision system showed a good correlation with actual length of the flower at a level of the coefficients of determination (R$^2$) of 0.9948 and 0.9993 for rose and chrysanthemum respectively and average measurement errors of the system were about 2% and 1% of the shortest length of the sample flowers. The experimental result showed that the machine vision system could be used successfully to measure length of the cut flowers. 2. Stem diameter of the cut flowers measured by the machine vision system showed a correlation with actual diameter at the coefficients of determination (R$^2$) of 0.8429 and 0.9380 for rose and chrysanthemum respectively and average measurement errors of the system were about 15% and 7.5% of the shortest diameter of the sample flowers which could be a serious source of error in grading operation. It was recommended that the error rate should be considered to set up grading conditions of each class of the cut flowers. 3. Bud maturity of 20 flowers each judged using the machine vision system showed a coincidence with the judgement by inspectors at ranges of 80%∼85% and 85%∼90% for rose and chrysanthemum respectively. Performance of the machine vision system to judge bud maturity could be improved through setting up more precise criteria to judge the maturity with more samples of the flowers. 4. Quality of flower judged by stem curvature using the machine vision system showed a coincidence with the judgement by inspectors at 90% for good and 85% for bad flowers of both rose and chrysanthemum. The levels of coincidence was considered as that the machine vision system used was an acceptable system to judge the quality of flower by stem curvature.

• Journal of Korean Society for Atmospheric Environment
• /
• v.17 no.E1
• /
• pp.9-16
• /
• 2001

To evaluate the correct separation capacity of cascade impactor for liquid aerosol, theoretical and experimental calculations of 50% cut-off diameter(ECOD(sub)50) were performed. A recalculation method of original diameter for hemispheric liquid aerosol collected on casecad impactor is also proposed newly using fixation technique. Calculated values for theoretical (ECOD(sub)50) of 40stage cascade impactor are 20, 6.4, 2.8, and 1.4$\mu\textrm{m}$ at 1st- ,2nd-, 3rd- and 4th-stage, respectively. A good agreement between the result of theoretical (ECOD(sub)50) and that og experimental ones was obtained at Stage 2 and 3. On the other hand, relatively large differences were found at Stage 1 and 4. Fixation for liquid aerosols using ${\alpha}$-cyanoacrylate monomer was performed successfully. The orignal diameter of liquid aerosols collected on each stage was calculated. The maximum levels of number size distribution curves at each stage are 19.8, 6.5, 3.1 and 1.5 $\mu\textrm{m}$ at 1st-, 2nd-, 3rd- and 4th-stage, respectively. The distortion of separation capacity of cascade impactor due to the split, merger, disappearance, and evaporation of liquid aerosols in the fluid did not occur.

• Journal of the Korean Geotechnical Society
• /
• v.23 no.8
• /
• pp.87-95
• /
• 2007

This study analyzed ground settlement and ground stress depending on tunnel excavation and the ground reinforcing grouting methods for double line road tunnel through deep weathered zone. Diameter of double line road tunnel was approximately 12m and umbrella arch method and side wall reinforcing grouting were applied. The ring-cut split excavation method and CD-cut excavation method for excavation method were applied. Analyses of failure rate and vertical stress ratio show that the tunnel for which the height of the cover (H) was higher than four times the diameter, can be considered a deep tunnel. Comparisons of various excavation and ground reinforcement methods showed that CD-cut method results in lower surface and crown settlement, and lower failure rate than that obtained by Ring-cut split method. In addition, the side wall reinforcing grouting resulted in reduction of tunnel displacement and settlement.

• Journal of Practical Agriculture & Fisheries Research
• /
• v.25 no.4
• /
• pp.78-83
• /
• 2024

This study was carried out to analyze the effect of changes in the light environment caused by the daylight disturbance on the growth, flowering, and cut flower quality of spray chrysanthemums. The spray chrysanthemum 'Yellow Cap' and 'Pitch PangPang' cultivars for cut flowers were artificially shaded to interfere with 66% of sunlight compared to the non-shading, and then the growing and flowering characteristics, and cut flower yield were investigated accordingly. There was no significant difference in the cut flower yield per unit area between the shading and the non-shading treatments. However, the number of days to flowering was 72.1 days for the 'Yellow Cap' and 65.2 days for the 'Pitch PangPang', which were delayed by 14.1 and 8.9 days, respectively, compared to the non-shading light. In the shading treatment, the flower diameter and the number of flowers also decreased by 10% and 15%, and 30% and 28% for both 'Yellow Cap' and 'Pitch PangPang', respectively. The stem length also decreased by 10% and 20%, the stem diameter by 23% and 37%, and fresh weight by 32% and 33%, respectively. The shading treatment delayed the flowering of chrysanthemums and reduced the growth such as flower diameter, number of flowers, and the length and weight of cut flowers. Based on these results, the daylight disturbance by artificial buildings is expected to reduce the productivity and quality of cut flowers by limiting the light intensity needed for chrysanthemum growth, flower bud differentiation, and flower development. Therefore, further research is needed on the rate of decrease in yield and market value according to the degree of shading to relieve damage to chrysanthemum growers caused by the daylight disturbance.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.11 no.3
• /
• pp.98-103
• /
• 2012

One of the problems in the grinding process using the machining center(MC) with a small diametric wheels is machining error due to decrease of the quill diameter. In this thesis, side-cut grinding is performed with a vitrified bonded CBN wheel on the machining center to establish the basis of the grinding using MC. The grinding force and machining error are investigated experimentally for the change of the machining condition. It is possible to estimate the machining performance by the ratio of the setting depth of cut and actual depth of cut. In addition, the relation between normal grinding force and machining error is presented by the experimental formula.

• Proceedings of the KSME Conference
• /
• 2001.11b
• /
• pp.365-370
• /
• 2001

In order to minimize unstable flow occurred at a multiblade fan/scroll system, optimal angle and shape of cut-off was determined by using two-dimensional turbulent fluid field analyses and neural network. The results of CFD analyses were used for learning as data of input and output of neural network. After learning neural network optimization process was accomplished for design variables, the angle and the shape of cut-off, in the design domain. As a result of optimization, the optimal angle and shape were obtained as 71 and 0.092 times the outer diameter of impeller, respectively, which are very similar values to previous studies. Finally, it was verified that the fluid field is very stable for optimal angle and shape of cut-off by two-dimensional CFD analysis.

• Journal of Bio-Environment Control
• /
• v.32 no.1
• /
• pp.15-22
• /
• 2023

Roses are one of the most produced flower species in the world, and cut roses are produced in the greenhouses all year round. Recently, due to the increase in the temperature in the greenhouses in summer, the quality of cut roses is seriously deteriorated, such as shortening the stem length. This study was conducted to investigate the effects of the growing seasons on the qualities of cut roses and also to test the effect of cooling at night in high temperature season on the cut flower qualities of roses. Comparing the qualities and yields of cut roses for each season, the major cut flower qualities such as flower stem length, stem diameter and fresh weight were statistically significantly decreased in roses ('Pink Beauty' and 'Pink Shine') produced in summer. The yields didn't show a statistically significant difference in both cultivars. Investigating the cut flower qualities, the flower stem length increased by 15% for 'Pink Beauty', 11% for 'Ararat', and 12% for 'Pink Shine' when treated with cooling at night in warm season than the untreated control. In addition, when treated with cooling at night in warm season, the fresh weight of all three cultivars increased by 20-30% statistically significantly than conventionally cultivated control. It is expected that cooling at night in warm season will be helpful to improve the cut flower quality deterioration in summer.