• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.4
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• pp.330-336
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• 2022

It is likely that the heading would occur early when air temperature increases. In 2022, however, the heading date was delayed unusually, e.g., by 3 to 5 days although temperature during the vegetative growth stage was higher than normal years. The objective of this study was to identify the cause of such event analyzing weather variables including average temperature, sunshine hours, and day-length for each growth stage. The observation data were collected for medium-late maturing varieties, which has been grown at crop yield experiment sites including Daegu, Andong, and Yesan. The difference in heading date was compared between growing seasons in 2021 and 2022 because crop management options, e.g., the cultivars and cultivation methods, were identical at those sites during the study period. It appeared that the heading date was delayed due to the difference in temperature responsiveness under a given day-length condition The effect of the temperature increase on the heading date differed between the periods during which when the day-length was more than 14.3 hours before and after the summer-solstice.. The effect of the temperature decrease during the period from which the day-length decreased to less than 14.3 hours to the heading date was relatively greater. This merits further studies to examine the response of rice to the temperature change under different day-length and sunshine duration in terms of heading.

• Korean Journal of Veterinary Research
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• v.37 no.4
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• pp.899-909
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• 1997

The aim of this study was to assess the estimates of the time of ovulation and mating derived by plasma progesterone concentration. The 40 mature Korea Jin-do bitches were monitored to determine the plasma progesterone concentrations from proestrus to parturition. Gestation length in the 30 pregnant bitches was $63.9{\pm}2.3$ ($mean{\pm}SD$) days in multiparous bitches and $61.8{\pm}3.6$ days in primiparous bitches when Day 0 was timed from the first day of male acceptance, and $61.4{\pm}1.8$ days and $61.3{\pm}2.7$ days when Day 0 was timed from the day of first mating, respectively. Also, gestation length was $63.1{\pm}1.4$ days, $62.4{\pm}1.1$ days and $61.5{\pm}0.9$ days in multiparous bitches, and $62.6{\pm}1.4$ days, $62.4{\pm}2.0$ days and $61.6{\pm}2.3$ days in primiparous bitches when Day 0 was timed from the day that plasma progesterone concentration was first increased above 2.0, 3.0 and 4.0ng/ml, respectively, and $53.8{\pm}3.1$ days and $54.8{\pm}2.6$ days when Day 0 was timed from the last day of male acceptance, respectively. In 30 pregnant bitches, plasma progesterone concentration was $0.2{\pm}0.2ng/ml$ in multiparous bitches and $0.7{\pm}0.8ng/ml$ in primiparous bitches at the first day of vulval bleeding, $1.9{\pm}1.0$ and $3.3{\pm}2.7ng/ml$ at the first day of male acceptance, $7.0{\pm}4.0$ and $9.3{\pm}6.2ng/ml$ at the day of first mating, and $25.1{\pm}6.3$ and $22.8{\pm}10.3ng/ml$ at the last day of male acceptance, respectively. When Day 0 was timed from the day of parturition, plasma progesterone concentration at Day -62, Day -63 and Day -64 was $4.7{\pm}2.7ng/ml$, $3.5{\pm}2.2ng/ml$ and $1.7{\pm}0.9ng/ml$ in multiparous bitches, and $5.3{\pm}4.4ng/ml$, $3.2{\pm}3.7ng/ml$ and $2.0{\pm}1.9ng/ml$ in primiparous bitches, respectively. When Day 0 was timed from the day that plasma progesterone concentration was first increased above 3.0ng/ml after the first day of vulval bleeding, plasma progesterone concentration at Day 61 and Day 62 was $2.7{\pm}2.2ng/ml$ and $1.4{\pm}1.9ng/ml$ in multiparous bitches, and $3.4{\pm}5.2ng/ml$ and $3.7{\pm}5.6ng/ml$ in primiparous bitches, and $0.8{\pm}0.7ng/ml$ and $0.9{\pm}0.4ng/ml$ at Day 63, respectively. It was that bitches were mated when plasma progesterone concentraion was 1.9 to 14.2ng/ml and 3.5 to 20.0ng/ml in multiparous and primiparous bitches, which was between first day before ovulation and fourth day after ovulation. And pregnancy rate was 92% (23/25). From these data, ovulation was estimated to occur the day when plasma progesterone concentration was first increased above 3.0ng/ml after the first day of vulval bleeding. It was estimated that mating time was the day when plasma progesterone concentration was between 1.9 and 20.0ng/ml, and best time for mating was between 3.0 and 8.0ng/ml of plasma progesterone concentration.

• Korean Journal of Plant Resources
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• v.10 no.1
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• pp.50-57
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• 1997

Using a bioassay for tuber enlargement activity, which was carried out with culture of microtuber of nodal stem segments in vitro, the endogenous substances was detected from leaves of yam(Diosorea alata L., cv. Solo Yam) treated under the short and the long day length condition. Tuber enlargement activity was found in both the aqueous and ethyl acetate phase of extract obtained from leaves of yams. Those activity was found in both the aqueous and ethyl acetate phase of extract obtained from leaves of yams. Those activities increased under the short day length, whereas not increased under the long day length. Guided by bioassay, the active substances in the ethyl acetate phase were purified by charcoal adsorption chromatography. The result obtained indicated that the 40% ethanol fraction contained the most prominent tuber enlargement activity. In seasonal changes of the leaves, tuber enlargement activity remained almost constant during summer(June-August), but after. the middle of September, the activity increased gradually and then reached a maximum in early October. Jasmonic acid (JA) was isolated with the guidance of microtuber test and identified by gas chromatography. The level of endogenous JA in the leaves of plants was more than $290{\mu}g/kg$ at the 10 hr day length. These results seem evidences for the occurrence of the tuber enlargement activity which is formed in leaves under the short days and transmitted to under ground part to induce growth and enlargement of tuber.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.4
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• pp.386-393
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• 1984

This study was carried out to identify the ecological characters easily changeable with the conditions of temperature and day-length and to ascertain the managable means which can optimize the barley plants to secure the maximae yield and early heading under controlled condition. Yield and yield components were greatly varied with temperature. Especially, effective tiller formation and grain filling of sub-tillers were more favorably affected by thermal treatment than those of main tiller. In thermic response, 'Kangbori' was less susceptible than others, while 'Sacheon #6' showed particular susceptability. The varietal differences of photoperiodic response were recognized on all investigated traits and their degree of response were similar to those with temperature. Among varieties, 'Kangbori' was comparably sensitive on several characters while 'Sacheon #6' displaying low light-sensitivity. The turning point at which heading might be radically stimulated was estimated as about 10.5 hour day-length in 3 tested varieties and above 18 hours of irradiance was considered ineffective for more rapid heading. The condition under which barley varieties may obtain maximal yield and resonably early heading was 15$^{\circ}C$ in temperature and 12 to 15 hours of day-length, regardless of varieties. of day-length, regardless of varieties.

• The Korea Journal of Herbology
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• v.25 no.1
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• pp.75-81
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• 2010

Objectives : It was investigated new herbal prescription HT005 supported by traditional Korean medicine has a activity on the longitudinal bone growth of rats. HT005 were consisted of the root of Angelica sinensis, the fruit of Alpinia oxyphylla, the root of Astragalus membranaceus, the stem of Eleutherococcus senticosus, and the root of Dioscorea japonica, and Poria cocos. Method : To investigate the effect on longitudinal bone growth in adolescent male Sprague-Dawley rats, the longitudinal length of growth plate was measured directly by the tetracycline fluorescent labeling method and chondrocyte staining method. HT005 administered orally for four days, and the tetracycline was injected twice on the growth plate of the animals for fluorescent dying. The rate of longitudinal bone growth was measured the length between the tetracycline bands which fixed on the 3rd day and 5th day after injection. Cresyl violet was also used to stain the chondrocytes in the growth plate. The length of growth plate after administration was compared. Expression of IGF-1 and BMP-2 in the growth plate was investigated by immunohistochemistry. Results : HT005 showed a significant longitudinal bone growth which was $301.0{\pm}6.1\;{\mu}m/day$ at the dose of 100 mg/kg and $283.8{\pm}1.25\;{\mu}m/day$ (p < 0.001)at the dose of 10 mg/kg of HT005, compared to control group by the tetracycline fluorescent labeling method. HT005 showed a significant chondrocyte length on growth plate which was measured $797.19{\pm}3.31\;{\mu}m$ (p < 0.001) at the dose of 100 mg/kg and $720.14{\pm}2.19$ (p < 0.001) ${\mu}m$ at the dose of 10 mg/kg compared to the control group by cresyl-violet staining method. Both the number and intensity of BMP-2 and IGF-1 positive cells were increased in the hypertrophic zone of growth plate. There was a significant correlation between BMP-2 and IGF-1 expression and heights of chondrocytes in growth plate. Conclusions : Treatment of HT005 on Sprague-Dawley rats markedly increased the longitudinal bone growth. Therefore, HT005 may be an alternative herbal source to growth hormone as it promotes bone growth in children afflicted by growth retardation.

• FLOWER RESEARCH JOURNAL
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• v.16 no.3
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• pp.161-167
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• 2008

Eight species of Korean native lilies were used as plant materials and investigated for the effect of temperature, day length, and sucrose on enlargement of bulblet in vitro. enlargement of bulblet was enhanced at $25^{\circ}C$ in most of Korean native lilies tested, meanwhile it was promoted at $20^{\circ}C$ in L. davuricum and L. hansonii. Moreover, enlargement of bublet was promoted under dark in L. concolor var. parthneion, L. distichum, L. amabile, and L. davuricum, to the contrary fresh weight was increased under longer day length in L. hansonii and L. maximowitzii. That of L. concolor var. parthneion and L. cernuum was not affected by light or dark condition. Fresh weight of the bulblets produced in vitro of most Korean native lilies tested was increased with increasing sucrose concentration and best at $120g{\cdot}L^{-1}$ sucrose in medium. However, enlargement of bublet was promoted by $60g{\cdot}L^{-1}$ sucrose in L. tsingtauense and L. cernuum and by $90g{\cdot}L^{-1}$ in L. davuricum. Bulblet enlargement tended to promote by lower rate of scaly leaf occurrence or separating bulblet and it was affected by occurrence of scaly leaf rather than separation of bulblet. However, occurrence of scaly leaf, separation of bulblet, and enlargement of bulblet were more significantly affected by genetic factors, species rather than culture conditions.

• Korean Journal of Optics and Photonics
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• v.12 no.2
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• pp.77-82
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• 2001

Error characteristics of a mirror loss measurement system using an exponential decay method were studied, with the two samples having about 200-ppm-loss and 30-ppm-loss, respectively. In order to minimize the decay signal deviation from an exponential curve due to cavity length fluctuation, a data average method was tried. The data average method significantly improved the exponential curve fitting error of the decay signal, so that for a 6 decay signal data average the loss measurement error was reduced by about 2.4 times for the 200-ppm-loss mirror and 1.3 times for the 30-ppm-loss mirror compared with a single shot measurement. Day-to-day mirror loss repeatability error for the two samples was investigated. The repeatability error was measured to be about 5% for the 200-ppm-loss mirror and about 26.4% for the 30-ppm-loss mirror. Low decay signal average effect and high repeatability error in the low loss mirror measurement were explained with non-uniform spatial loss distribution of the sample and contamination from the environment, in addition to the error sources of the mirror loss measurement system itself. The influence of cavity length fluctuation and cavity length measurement error on the mirror loss measurement system performance was theoretically calculated. It confirmed that the requirement for the cavity length parameters was not so strict in the mirror loss measurement system of several ppm resolution. ution.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.4
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• pp.433-440
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• 2009

Korean sweetpotato, Ipomoea batatas, varieties were examined for their flowering response as a fundamental research to improve breeding efficiency by hybridization of this crop. Under 10.0~10.5 hours short day condition, self-rooted plants of three varieties such as Shinmi, Hongmi and Hwangmi flowered sparsely or moderately, and those of fourteen varieties including Eunmi flowered very sparsely. Under 10.6~12.0 hours day length condition, self-rooted plants of three varieties such as Shinmi, Hongmi and Hwangmi flowered very sparsely. Under the day length longer than 12 hours, none of the tested plants flowered. In all the sweetpotato plants grafted on morning glory, flowering occurred with varying degrees by varieties and day lengths. Under 10.0~10.5 hours day length, thirty two varieties including Hongmi flowered moderately or profusely, and one variety such as Mokgye 1 flowered sparsely. Under 10.6~12 hours day length, twenty three varieties including Sinchunmi flowered moderately or profusely, nine varieties including Jeungmi flowered sparsely, and Mokgye 1 didn't flower at all.

• Journal of architectural history
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• v.25 no.4
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• pp.7-18
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• 2016

This thesis mainly deals with how 'count of Ryang' was used in Joseon dynasty. Count of Ryang means how many purlins were used in the building with longitudinal section. As a result, the notion of Ryang in Joseon dynasty does not differ from now one. But the usages of that are slightly different to the present day. In Joseon dynasty, count of Ryang mainly was appeared with another word, count of Kan. Count of Kan has two meanings. One is the length, and the other is the area of building. When they used the count of Ryang combined with Kan, count of Kan had the meaning of length. By doing that, count of Ryang indicates the size of flank, count of Kan indicates the length of front. In the 19th century, count of Ryang looks similar to the past, but count of Kan shows another aspect. It did not indicate the length but the area of building. Through this study, although the usages of Ryang were different to the present, the concepts of Ryang were similar in Joseon dynasty.

• Magazine of the Korean Society of Agricultural Engineers
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• v.41 no.3
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• pp.59-65
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• 1999

This study has been performed to confirm the three dimensional effect of the crack reduction and the restrained effect of crack growth for the synthetic fiber reinforced soil. Two types of polyrpropylene fiber and low plastic clay(CL) were used for the test. And the test variable were fiber length and so on. The results of the study were summarized as follows ; 1) The mixing of synthetic fiber was effective in reducing crack growth due to adhesion between soil partlcles and synthetic fiber.l Especially initlal crack was delayed, as compared with the pure soil, for about 1 day in case of mono filament synthetic fiber and for about 1 or 2 days in case of fibrillated syntetic fiber. 2) As the content and length of synthetic fiber were increased , the effect of crack reduction was increased. It was found that 0.5% fibrillated synthetic fiber with 40mm length reinforced soil had about 3 times more effective than natural soils. 3) In case of the same fiber content and fiber length, the fibrillated synthetic fiber has nmore effective than the mono filament synthetic fiber for crack reduction.