• Journal of Ocean Engineering and Technology
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• v.23 no.6
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• pp.61-66
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• 2009

For a spread-moored FPSO (Floating Production, Storage, & Off-loading) subjected to environmental excitation from waves, current, and wind, a procedure to determine optimum length and stiffness of mooring lines is suggested using quasi-static frequency domain response analyses. Coupled relations between design parameters are closely examined. In consideration of this, optimized design parameters are proposed based on minimum weight condition. The initial design parameters for numerical analyses are calculated using the static catenary equation of mooring lines. It is demonstrated the line tension and vessel's offset are influenced by the mooring line length and stiffness. Accordingly it is suggested the optimum vessel's offset range should be determined considering line fatigue damage. The availability and limitation of the application of quasi-static analysis method for spread mooring system are explained by comparing the result of time domain analysis with one of frequency domain analysis.

• Journal of Environmental Science International
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• v.23 no.5
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• pp.771-780
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• 2014

Tetragonia tetragonides is a medicinal plant native to ocean sand soil of southern provinces and has significant effects on the prevention and curing of gastroenteric disorders. Despite of its popularity, supply of the plant has never met the level of demand because of the absence of an adequate culturing method. The present study, thereby, was conducted for classifying the plants with geographically different characteristics, studying growth habits, developing a new culturing method and establishing a large scale propagation system of selected superior individual plants. The study was also aimed for revealing optimum conditions for seed treatment, fertilization, and efficient culturing system and thereby, for utilizing the plant as a new income source for rural communities. The seed was elongated with size of 2.6 mm (width) ${\times}$ 1.8 mm (length). No difference in seed size was observed depending on different inhabitate. Each flower produced about 4.5~4.8 seeds. Germination rate was high for seeds matured for 40 days after fertilization, but deceased to 50% for seeds matured only for 20 or 30 days. Seed dormancy lasted 6 months and seed storage at humid $5^{\circ}C$ facilitated germination. Mechanical obstruct of seed germination was due to seed coat and removal of seed coat enhanced the germination rate. Optimum temp. for seed storage was $5^{\circ}C$, and high germination rate was maintained for 350 days. However, for stratification condition or at room temperature, germination was significantly reduced as storage time increased Optimum treatment of plant growth regulators was soaking in $GA_3$ 250 mg/L for 1 hr. The priming treatment with 50 mM $Ca(NO_3)_2$ at $20^{\circ}C$ for two days improved the seed germination with 10% compared to non-treated control. The treatment of 20% NaOCl for 3 hr. improved the seed germination rate up to 10% and 1 day ahead.

• Applied Biological Chemistry
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• v.41 no.2
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• pp.141-146
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• 1998

In order to determine the optimmum harvest time of Citrus unshiu Marc. var. miyagawa and C. unshiu Marc. var. okitsu produced in Cheju, citrus fruits sampled at packing houses or harvested directly on citrus tree in south and north area of Cheju were analyzed. The fruits were grown in size till middle of October, and soluble solids were increased continuously after that. The fruits size were different by positional directions on the tree, the quality of citrus fruits in central southern positions on the tree was good for fresh fruit consumptions. Compared with only the quality of citrus fruits as a factor of soluble solids, total sugar, pH, and color index, the optimum harvest time were supposed to be reasonable at late of November for C. unshiu Marc. var. okitsu, and at early of December for C. unshiu Marc. var. miyagawa. The results obtained from citrus fruits sampled at packing houses were supposed to be not suitable for determing the optimum harvest time, because of storage after harvest at ordinary harvesting time.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.41 no.4
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• pp.73-81
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• 2009

The document archives like official documents, books, maps and historic paper artifacts are primarily based on the organic cellulosic materials. As the passage of time, these organic cellulosic materials are slowly deteriorated by various aging factors, like light, polluted air and biological fungi. Many researchers have been carried out the examination method of deteriorating origins, the mechanism of aging hysteresis, and the preserving method of archival materials. One of the most simple and easiest ways for conservation of organic archival documents is the proper storage under environmental control. Corrugated board for archival quality container has been developed and already used in advanced country, like Japan, USA, German, UK and Europe. In case of Korea, corrugated board for archival quality container has been used a decade ago, but totally imported. This study was tried to develop the corrugated board for archival quality container. Liner and corrugated medium were specially produced and finally manufactured to E flute corrugated board. The physical and strength properties of permanent base paper and corrugated board were evaluated, and compared with imported corrugated board. 4 kinds of corrugating adhesives were considered various in order to investigate optimum adhesive for flute development between liner and corrugating medium, and evaluate adhesion strength under conditions of storage and curing temperatures.

• Korean Journal of Medicinal Crop Science
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• v.27 no.6
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• pp.390-396
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• 2019

Background: Usually ginseng seeds are sown during autumn and spring. Sowing in spring often results in poorer seedling establishment than in autumn. One of the reasons for poor germination could be cold-treatment condition for breakage of physiological dormancy during winter. Here we tested the effects of storage temperature used during cold treatment on germination. Methods and Results: Germination properties were observed after dehiscent seeds were stored as wet and dry at 2℃, -2℃, -3.5℃ and alternating temperature (AT). Seed dryness and storage temperature affected germination properties (p < 0.01). Wet and AT condition germinated highest, and wet and -3.5℃ condition germinated lowest, which was 91.2% and 1.4% respectively. Mean germination time (MGT) of the wet and AT condition was faster than other treatments at 2.4 days, and the dry and -2℃ condition was the longest. Germination performance index (GPI) was highest for wet and AT condition (37.7%) and the lowest for wet and -3.5℃ condition (0.5%). The growth of above-ground and below-ground were the best for wet and 2℃ condition, and wet seeds showed better growth than dry seeds (p < 0.01). Conclusions: For cold treatment, ginseng seeds may not be stored below -2℃ for successful germination during spring sowing.

• Korean Journal of Agricultural Science
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• v.43 no.3
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• pp.340-345
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• 2016

The kiwi fruit (Actinidia deliciosa cv. 'Hayward') should be ripened at any step during postharvest handling before consumer consumption. This is essential for freshly harvested kiwi fruit. But, this requires correct temperatures and ethylene concentrations. More testing of a newly developed ethylene generator using charcoal for commercial purposes is needed. This study was conducted to investigate the optimum storage temperatures and the effect of ethylene on the postharvest quality of kiwi fruit. Three different ethylene concentrations of 10, 50, and $100{\mu}L{\cdot}L^{-1}$ were used on fresh kiwi fruit stored at different temperatures of 10, 15, and $20^{\circ}C$. The quality changes of the fruits were assessed by sensory evaluation and by measuring firmness, soluble solids content, titratable acidity, and ethylene production. Higher storage temperatures and ethylene concentrations softened the kiwi fruit quickly and led to the rapid loss of acidity while soluble solid contents of fruit increased to a significant extent during the same storage period. Similarly, the firmness of ethylene-treated fruits stored at 20 and $15^{\circ}C$ dramatically decreased in the experiment while treated fruits stored at $10^{\circ}C$ decreased only slightly. Quality characteristics of kiwi fruits stored at 15 and $20^{\circ}C$ were better than those of fruits at $10^{\circ}C$. With regards to the effect of temperature, fruits stored at lower temperatures took a longer time to ripen and retained their quality longer. The newly developed ethylene generator maintained the ethylene concentration in the 5 kg box at $40-400{\mu}L{\cdot}L^{-1}$. The ethylene generator could also be used to soften persimmons.

• Journal of the Korean Society of Food Science and Nutrition
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• v.5 no.1
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• pp.19-24
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• 1976

A determination of proper maturity is a significant factor for a good quality and storage. This study is aimed at a determination of optimum harvest date related to a decisive measuring of maturity in Spur Golden Delicious. In this case, respiratory status and other characteristics are taken as a indicator for maturing determination. The results are as follows. 1. Respiratory rate has been decreased through a fruit development and come to its minimized point on Sep. 25. at last. On the contrary its tendency has been increased after Sep. 25. It is also estimated that the former is pre-climacteric, the latter climacteric rise based on dimacteric minimum Sep. 25. 2. A flesh hardness has maintained comparably high value until Sep. 18. But in the point of climacteric minimum, Sep. 25, curve of flesh firmness has rapidly been broken down, and after Sep. 25, tendency has slowly decreased at the sucessive date. 3. Pectin content, optimum acidity are remarkably decreased after Sep. 25, Oct. 2 respectively. 4. When water soluble sugar content shows to be swung from climacteric minimum, any resonable tendency are not found. 5. In this experiment, optimum harvest time is found by Oct. 2, in time of 145 days after flowering.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.1
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• pp.45-49
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• 2002

This study was conducted to enhance the value of chamnamul (Pimpinella brachycarpa (Komarov) $N_{AKAI}$) as an useful food resource. Hunter L, a, b values (lightness, redness, yellowness) of chamnamul leaf were 33.28$\pm$1.94, -10.98$\pm$0.74, 14.05$\pm$1.29 and shearing force was 2745.2g. Contents of tannin and dietary fiber were 100.9 mg%, 24.0% (freeze drying base). The minerals identified in chamnamul were Ca 7.85 g/kg, K 76.31 g/kg, Mg 4.78g/kg, Fe 0.35g/kg, Na 2.35 g/kg. Chamnamul kimchi was packed in polyethylene film (200g) and fermented at 2$0^{\circ}C$ and 4$^{\circ}C$. In color changes kimchi fermented at 2$0^{\circ}C$ showed more increase in Hunter L, a, b values than kimchi fermented at 4$^{\circ}C$. The pH of kimchi decreased and acidity increased with storage time at both temperature. Ascorbic acid contents decreased sharply with storage time. Loss of ascorbic acid contents was about 81.9% in kimchi fermented at 2$0^{\circ}C$ after 5 days, and kimchi fermented 4$^{\circ}C$ lost 77.3% of ascorbic acid after 30 days. Also reducing sugar contents decreased with storage time at 2$0^{\circ}C$ and 4$^{\circ}C$. The results of sensory evaluation showed that optimum ripening time of chamnamul kimchi was 1~3 days at 2$0^{\circ}C$ and more than 20 days at 4$^{\circ}C$.>.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.2
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• pp.235-244
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• 2011

The physicochemical properties and quality changes in salted and dried brown croaker products using deep seawater salt were investigated for preparation with different pretreatment, salting and drying conditions. Optimum salt concentration, salting time and drying time for product were 20% of body weight, 12 hrs at room temperature ($25{\pm}2^{\circ}C$), and 24 hrs at $30{\pm}2^{\circ}C$, respectively. The volatile basic nitrogen (VBN), peroxide value (POV), viable cell count and acid value (AV) of viscera and blade removed products were 18.9~22.4 mg%, 21.0~32.5 meq/L, and 2.3~4.4 mg/mL, $2.0\sim3.5{\times}10^3$ CFU/g, respectively and only viscera removed products were 31.2~38.1 mg%, 40~55.2 meq/L, 7.0~11.5 mg/mL, $4.1\sim5.5{\times}10^3$ CFU/g, respectively. Changes in quality of salted and dried brown croaker products were investigated during storage at room temperature and $5{\pm}2^{\circ}C$. The POV, AV and viable cell counts of salted and dried brown croaker products increased in commercial salt used and only viscera removed products compared with deep seawater salt used and viscera and blade removed products during storage time. Results in this study showed that the deep seawater salt was very effective for quality control of salted and dried brown croaker products and pretreatment method was a very important factor for preparation products. The optimum conditions for preparation of salted and dried brown croaker product were 20% of body weight for salt concentration, 12 hrs at $25{\pm}2^{\circ}C$ for salting time, and 24 hrs at $30{\pm}2^{\circ}C$ for drying time. Optimum storage time for quality maintenance was 14 days at $5{\pm}2^{\circ}C$.

• Food Science and Preservation
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• v.21 no.4
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• pp.468-472
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• 2014

The effect of pre-storage treatments was investigated to control the occurrence of fruit skin stain in 'Niitaka' pears. The incidence of fruit skin stains was significantly reduced when the fruits were stored in paper bags with a yellow inner color, compared to when they were stored in paper bags with blue and red inner colors. Additionally, the pear fruits that were harvested seven days earlier than their optimum maturity date developed less fruit skin stains in cold storage and retained their quality. Storage in polyethylene (PE) bags did not control the occurrence of fruit skin stains as effectively as did bag-free storage or storage in calcium-coated bags. The dipping of the pear fruits in a chlorine dioxide and calcium solution was highly effective in reducing the fruit skin stains compared to when they were not dipped or when they were dipped only in distilled water. In particular, a 1,500 times diluted solution of sodium dichloroisocyannurate (NaDCC) reduced the incidence of fruit skin stains and the size of the lesions. No stain was observed on the skin of the fruit with a water content lower than 67.7% (w/v) during its storage. In conclusion, packaging pear fruits in bags with an inner calcium coat and dipping them in a chlorine dioxide, calcium, or NaDCC solution can effectively reduce their skin stains during their storage.