• Horticultural Science & Technology
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• v.31 no.6
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• pp.666-676
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• 2013

The study was carried out to examine the initial point of dormancy, breaking time of internal dormancy, and to find out the accumulated hours of low temperature (under $7.2^{\circ}C$ from $0.0^{\circ}C$ to $7.2^{\circ}C$) for bud-breaking. Over-all, the chilling requirement for breaking of internal dormancy in the commercial apple cultivars ('Fuji' and 'Tsugaru') and apple cultivars bred in Korea ('Hongro', 'Sunhong', 'Honggeum', 'Hongan', 'Hongso', 'Gamhong', 'Summer dream') at the Gunwi region for 4 years (from 2009 to 2012) was investigated. Also, the breaking time of internal dormancy in the field at the Gunwi region and the breaking time of dormancy if air temperature of Gunwi region rises $4^{\circ}C$ higher than the current one were investigated using the same data. The initial point of dormancy was set at the time when the lateral bud breaking did not occurred (when heading back cutting was done in the middle of terminal shoots). The occurrence of the breaking of internal dormancy was decided if the breaking of the terminal bud of bourse shoot occurred within 15 days or not in growth chamber. About 100 bourse shoots were collected by cultivar classification in early December every year and were stored at $5.0^{\circ}C$, and they were placed in growth chamber at one week interval. The chilling requirement of cultivars was expressed in accumulated hours in the field and in the growth chamber under $7.2^{\circ}C$ and $0.0-7.2^{\circ}C$ from the initial point of dormancy to the breaking time of internal dormancy. The results showed that the initial point of dormancy in selected cultivars could occur at the end of September. The breaking time of internal dormancy could occur from the end of January to the early of February. The accumulated hours under $7.2^{\circ}C$ for breaking of internal dormancy were 1,600-2,000 hours, while those of $0.0-7.2^{\circ}C$ were 1,300-1,800 hours. In comparing the different apple cultivars, the chilling requirement of the early flowering cultivars seemed lower than that of the late-flowering cultivars. Based on these results, if the air temperature of Gunwi region rises about $4.0^{\circ}C$ higher than the current one, the breaking time of internal dormancy will be delayed by 2-4 weeks.

• Korean Journal of Agricultural and Forest Meteorology
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• v.11 no.2
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• pp.52-60
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• 2009

This study was conducted to quantify the soil respiratory $CO_2$ emission (SR) in an apple orchard and to determine its relationship with key environmental factors such as air temperature, soil temperature and soil moisture content. Experiment was made over the period from 23 April 2007 to 31 March 2008 in 'Fuji' apple orchard of National Institute of Horticultural and Herbal Science in Suwon, Gyeonggi-do, Korea. The SR was measured by using the automatic opening/closing chamber system based on a closed method. Diurnal variations in SR showed an increase around 0700 hours with increasing soil temperature, its peak between 1400 and 1500 hours, and then a gradual decrease thereafter. Daily variations in SR depended largely on soil and air temperatures over the year, ranging from 0.8 to 13.7 g $CO_2$ $m^{-2}d^{-1}$. During the rainy spell in summer (July$\sim$Autumn) with higher temperature and more precipitation, the SR was lower than that in the spring (May$\sim$June) with moderate temperature. The SR showed a significant exponential relationship with soil temperature ($r^2=0.800$) and air temperature ($r^2=0.805$), but not with soil moisture content ($r^2=0.160$). The $Q_{10}$ values of SR with annual soil temperature and air temperature were 2.0 and 1.9, respectively. The annually integrated SR was 19.6 ton $CO_2$ $ha^{-1}$.

• Journal of Sensor Science and Technology
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• v.11 no.1
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• pp.9-17
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• 2002

The forming conditions of X-ray storage phosrhors $BaFBr_{1-x}I_x:Eu^{2+}$, $Na^+$ have been investigated, and measured the PSL emission spectra and its intensity, fading characteristics and does dependence of the prepared phosphors. These characteristics were compared with those of commercial image plate (ST-III) obtained from Fuji Photo Film Co. The optimal preparing conditions of $BaFBr_{1-x}I_x:Eu^{2+}$, $Na^+$ Phosphor were 0.5 mol% of $EuF_3$, 4.0 mol% of NaF and composition ratio x=0.3, and the sintering temperature were $950^{\circ}C$ in $H_2$ atmosphere. When the composition ratio x was equal to 0, the spectral range of the luminescence of $BaFBr_{1-x}I_x:Eu^{2+}$, $Na^+$ phosphor was $365{\sim}420\;nm$, and its maximum luminescence intensity appeared at 390 nm. When composition ratio x was not equal to 0, the wavelength ranges and peak of the spectra were shifted to the longer wavelength with the growth of composition ratio x. A good linearity was shown between the PSL intensity and X-ray irradiation dose. The phosphor sample with x=0.3 exhibited better fading characteristics than that of other $BaFBr_{1-x}I_x:Eu^{2+}$ phosphor samples, and the fading characteristics of the PSL intensity at room temperature were shown poorer with increasing $I^-$ ion concentration. The lattice constant of the phosphor becomes larger with increasing the $I^-$ ion concentration.

• Food Science and Preservation
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• v.19 no.3
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• pp.413-419
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• 2012

Fermentation of ice apple wine from freeze-concentrated Fuji apple juice to 36 $^{\circ}Brix$ was carried out using Saccharomyces cerevisiae SS89, a sugar-tolerant wine yeast strain. The characteristics of the fermentation and the properties of ice apple wine were compared with those of S. cerevisiae W-3, an industrial wine yeast that was used as a control in this study. During the fermentation, the alcohol content increased more rapidly by S. cerevisiae SS89 together with the decrease of the soluble solid content, compared to S. cerevisiae W-3. It reached 12% (v/v) after 15 days of fermentation by S. cerevisiae SS89 (12.4%, v/v) and 21 days by S. cerevisiae W-3 (12.6%, v/v). The soluble solid contents of the SS89 and W-3 wines were 24.0 and 23.6 $^{\circ}Brix$, respectively. Lactic acid was detected at the highest level, followed by malic aid, among the organic acids in both wines. No big differences in the organic acid contents were observed based on the strains. In the SS89 wine, higher levels of methanol, propanol, butanol, and isoamyl alcohol were detected, together with a lower isobutanol content, compared with the W-3 wine. The SS89 wine showed higher level of intensity as well as higher Hunter's L and b color values compared to the W-3 wine. In the sensory evaluation, similar scores in color, flavor, taste, and overall preference were obtained in the two wines. Therefore, S. cerevisiae SS89 was thought to be useful for the rapid fermentation of ice apple wine.

• Food Science and Preservation
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• v.18 no.4
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• pp.559-566
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• 2011

In this study, the good brewing conditions for the 24 $^{\circ}Brix$ freeze-concentrated apple wine were investigated. The four selected Saccharomyces cerevisiae strains MM10, SS89, SS812, and WW108, could ferment quickly when brewed with high sugar levels. During the fermentation, the reducing sugar contents slowly declined while the total acid in all the yeasts increased and the final alcohol content was 12-13%, a typical wine's alcohol content. The viable counts were shown to be 6-6.8 log cfu/ml. During the fermentation, the organic acid content was shown to be within the range of 2.36-3.11%, and the free sugar content, except for the SS89 and WW108 strains, was shown to consist only of sorbitol, although fructose was somewhat detected in the SS89 and WW108 strains. Methanol was not detected, or only a trace of it was detected, and the aldehyde content was 107.68-114.27 ppm. As for the fusel oil contents, a trace of propanol was detected. Isobutanol and butanol were present in 40.16-54.65 and 25.47-27.73 ppm, respectively. The isoamy1 alcohol content was shown to be the highest (108.88-217.26 ppm). The final total phenolic compounds were shown to be 0.1-0.16%. The final Hue values were shown to be 1.3-3.6, and the final intensity was 0.1-0.45. The lightness (L) was within the range of 91.78-98.51, the redness (a) was at a neutral position at red and green, and the yellowness (b) was within the range of 2.38-7.7. In the sensory evaluation, the SS812 strain was found to be the best in terms of color, the SS89 strain in terms of odor, and the WW108 strain in terms of taste. Overall, SS812 was found to be the best apple wine.

• Korean Journal of Agricultural and Forest Meteorology
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• v.19 no.4
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• pp.252-269
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• 2017

This study was carried out to examine the base temperature to flowering and the average days to flowering by accumulated hours of low temperature ($5.0^{\circ}C$) or changing temperature after bud breaking. Over-all, the prediction of flowering time in the commercial apple cultivars ('Fuji' and 'Tsugaru') and apple cultivars ('Chukwang', 'Gamhong', 'Hongan', 'Honggeum', 'Hongro', 'Hongso', 'Hwahong', 'Summer dream', 'Sunhong') bred in Korea at the Gunwi region for 4 years (from 2009 to 2012) was investigated. Also, this study estimated the flowering time when the air temperature of Gunwi region rises at $5.0^{\circ}C$ was investigated using the same data. The range of accumulated hours of low temperature (chilling requirement) was from 0 hour to 1,671 hours, and the range of high temperature (heat requirements) to flowering after low temperature treatment was from $5.0^{\circ}C$ to $29.0^{\circ}C$. The treatments of changing temperature after bud breaking were classified as constant temperature treatment (control) and $5.0{\sim}10.0^{\circ}C$ elevation or descent treatments. The results show that the average days to flowering was longer with shorter accumulated hours of low temperature, and the average days from bud breaking to flowering of 0 hour treatment was longer about 2~4 weeks than that of 1,335~1,503 hours treatments. In comparing to apple cultivars, the all cultivars were not flowered under $10.0^{\circ}C$ after bud breaking, and the cultivars with low chilling requirements needed low heat requirements for flowering. The average days to flowering of treatments that the air temperature after bud breaking was controlled about $15.0^{\circ}C$ was shorter about 1~3 weeks than that of treatments was controlled about $10.0^{\circ}C$. In the treatment of changing temperature after bud breaking, the average days from bud breaking to flowering of temperature elevation treatment was shorter than that of constant temperature treatment. By use of these results, the base temperature to flowering of main apple cultivars in Korea was seemed to $10.0^{\circ}C$, and if the air temperature of Gunwi region rises about $5.0^{\circ}C$ than that of current, the flowering time was estimated to be delayed by 1 week.

• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.90-98
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• 1996

The mineral contents were analyzed for 12 varieties of Korean apples and 9 commercial apple juices by atomic absorption spectrophotometry. On the fresh matter basis, the ash contents of tested apples ranged 0.21-0.48%, Mn 0.20-2.52 ppm, Cu 0.10-1.03 ppm, Fe 0.24-9.88 ppm, Zn 0.09-1.06 ppm, Mg 21.08-99.00 ppm, Ca 15.16-99.56 ppm, K 842.10-1788.10 ppm, Na 10.32-40.53 ppm, P 24.43-90.07 ppm, Pb nd-98.05 ppb, Cd nd-36.08 ppb and Cr 2.25-123.76 ppb. Overally mineral contents of Aori and Jonathan were higher than those of Fuji. The mineral contents of apple cultivated at Wonju, Kangwon and Taegu, $Ky{\check{o}}ngbuk$ were higher than those of the other growing region. The mineral contents of commercial apple juice were ash 0.13-0.36%, Mn 0.24-0.99 ppm, Cu 0.10-0.61 ppm, Fe 0.19-3.70 ppm. Zn 0.20-1.77 ppm, Mg 18.16-49.56 ppm, Ca 14.42-42.30 ppm, K 785.07-1440.30 ppm, Na 14.71-52.58 ppm, P 16.57-63.56 ppm, Pb nd-95.55 ppb, Cd nd-17.65 ppb and Cr 8.60-110.98 ppb, respectively. Comparing mineral contents of apples and commercial apple juices, Cu, Mg, K, Ca and Fe contents of apples were higher and Zn, Na contents were lower than those of apple Juices.

• Research in Plant Disease
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• v.28 no.4
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• pp.221-230
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• 2022

The fire blight caused by Erwinia amylovora (Ea) was first reported in 2015 in Korea, and the disease has rapidly spread to 22 regions until 2021. In Korea, all host plants in the apple and pear orchards where fire blight occurred should be eliminated and buried by the Plant Protection Act. To prevent the spread of the disease, all burial sites were prohibited from planting the new host plants for the next three years. To confirm the eradication efficiency of Ea and the reoccurrence of fire blight, the surveillance facilities were established on three burial sites from 2019 to 2020 in Anseong-si, Gyeonggi-do, and Chungju-si, Chungcheongbuk-do. As host plants, five apple trees of fire blight-susceptible cultivar 'Fuji', were planted in each facility. All facilities were enclosed with fences and nets and equipped with two CCTVs, motion sensors, and several other sensors for recording weather conditions to monitor the environment of the sentinel plants in real-time. The sentinel plants were checked for the reoccurrence of fire blight routinely. Suspicious plant parts were collected and analyzed for Ea detection by loop-mediated isothermal amplification polymerase chain reaction and conventional polymerase chain reaction. Until November 2022, Ea has not been detected in all sentinel plants. These results might support that the burial control of infected plants in soil works efficiently to remove Ea and support the possibility to shorten the prohibition period of host plant establishment in the burial sites.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.4
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• pp.406-415
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• 2009

Purpose: The purpose of this study was to compare the marginal fitness and fracture load of the zirconia copings according to the design with different thickness and coloration. Material and methods: The evaluation was based on 80 zirconia copings. Zirconia copings were fabricated in design with different thicknesses using CAD/CAM system (Everset, KAVO dental GmbH, Biberach, Germany). The designs of copings were divided into four groups. The first group consisted of copings with uniform thickness of 0.3 mm. The thickness in the second group was 0.3 mm on the buccal surface and 0.6 mm on the lingual surface. The third group consisted of coping with uniform thickness of 0.6 mm. The thickness in the fourth group was 0.6 mm on the buccal surface and 1mm on the lingual surface. Each group consisted of 10 colored and 10 uncolored copings. Half of the copings (40) processed with a milling system according to the specific design were sent to be given a color (A3) through saturation in special dye by a manufacturing company. Just after sintering, the marginal discrepancies of copings were measured on the buccal, lingual, mesial and distal surfaces of metal die, under a Video Microscope System (sv-35, Sometech, Seoul, Korea) at a magnification of $\times$ 100. It was remeasured after the adjusting of the inner surface. Next, all copings were luted to the metal dies using reinforced cement {GC FujiCEM (GC Corp. Tokyo, Japan)} and mounted on the testing jig in a Universal Testing Machine (Instron 4467, Norwood, MA, USA). The results were analyzed statistically using the one-way ANOVA test. Results: The obtained results were as follow: 1. The measured value of marginal discrepancy right after sintering was the greatest in the contraction of the buccal area in all groups, except for group I2. 2. There was no significant difference of marginal fitness among the groups in the colored zirconia group (P<.05). 3. When the marginal fitness among the groups in the uncolored zirconia group was considered, group II2 had the smallest marginal discrepancy. 4. When the colored and uncolored groups with the same design were compared, there was a significant difference between I1 and II1 groups. In group 2, 3, and 4, the uncolored zirconia had the greatest marginal fitness (P<.05). 5. After adjustment of inner surface, there was no significant difference in the marginal fitness in all groups when color and design of the zirconia coping were compared. 6. The fracture load of CAD/CAM zirconia copings showed significant difference in group 1, 2, 3, and 4. I4 and II4 had the strongest fracture load. 7. When groups with different color and same design were compared, all colored groups showed greater fracture load (P>.05), with no significance. Conclusion: There was difference in the marginal fitness according to the design and coloration of zirconia copings right after sintering, but it was decided that the copings may well be used clinically if the inner surface are adjusted. The copings should be thick enough for the reinforcement of fracture strength. But considering the esthetics of the visible surfaces (labial and buccal surface), the thickness of copings may be a little thin, without giving any significant effect on the fracture strength. This type of design may be considered when giving priority to preservation of tooth or esthetics.