• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.2
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• pp.97-102
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• 2000

This experiment was conducted to investigate the changes of harvest index and the relationship between harvest index and yield determination factors by different planting times in the determinate soybean cultivars, Shinpaldal and Danbaeg. Optimum planting were 23 May in 1995 and 1996. Late planting were 13 June in 1995 and 6 June in 1996. Growth period from planting to physiological maturity (R7) was shortened as planting time was delayed in two cultivars due to shortening of reproductive growth period in Shinpaldal, and of vegetative growth period in Danbaeg. Stem weight was distinctly decreased in late planting compared to optimum planting, but seed weight of both cultivars was not different between planting times. Also, seed number per pod and harvest index were significantly increased in late planting and the high correlation was found between two factors. It was suggested that increase of harvest index in late planting would be related with high assimilate use efficiency due to increase of sink capacity. The results of correlation and principal component analysis for yield determination factors showed that main factor on yield determination was pod number per plant at R5 stage associated with dry matter accumulation during early reproductive growth period, seed number per pod and harvest index were the second factor, and one hundred seed weight was the third factor. The result of this experiment indicated that yield determination in soy-bean was dependent mainly on pod number per plant related to dry matter accumulation by early reproductive growth period, and the increase of seed number per pod and harvest index could compensate for yield decrease by shortening of vegetative growth period in late planting. Such result suggests that optimum planting date can be delayed from mid May to early June in improved soybean cultivars in Korea.

• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.4
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• pp.694-699
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• 2007

Delayed tooth eruption is the most commonly encountered deviation from normal eruption time. Racial, ethnic, sexual, and individual factors can influence eruption and are usually considered in determining the standards of normal eruption. Delayed tooth eruption was affect to the dentition and facial growth, so that when it occurred careful evaluation should be performed to establish the cause and the treatment plan accordingly. Present 3 cases of delayed tooth eruption by periapical lesion, underdevelopment of incisior and compound odontoma were successfully treated. In these cases, we could observe spontaneous eruption of the delayed erupting tooth after removal of interrupting factor and space regaining with maintaining.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.5
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• pp.13-20
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• 2012

In order to clarify the effect of overload on crack growth behaviors, fatigue tests for overload were carried out for round plain specimens of SM45C steel. In the experiment, typical semi-elliptical crack shape was found and further crack growth behaviors were tested. Using three types of single overload fatigue tests, Crack growth retardation phenomenon were examined. The growth rate of surface crack(da/dN) during retardation period was analyzed in terms of ${\Delta}K$ and ${\Delta}K_{eff}$. On the growth rate of surface crack analyzed by ${\Delta}K$, the dependence of overload stress levels appears. However, on the growth rate by ${\Delta}K_{eff}$ obtained by Willenborg analysis, there is a non-liner relationship between da/dN and ${\Delta}K_{eff}$ with narrow scatter band.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.6
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• pp.366-369
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• 2000

This study was conducted to determine the effect of seeding date on the days and the accumulated temperatures to development stages, leaf emergence, and yield in spring-planted barley. Two barley varieties, Sacheon #6 in spring type (growth habit I) and Saechalssalbori in winter type (growth habit IV), were seeded on four seeding date, Feb. 23, March 4, March 13, and March 24. Growth periods to emergence, heading and maturity were shorten when seeding dates were delayed, except for the heading date of Saechalssalbori (winter type barley)at the later seeding date. The rate of leaf emergence was 0.1915 in a day, and was slightly high when seeding was delayed. The accumulated temperatures were 111-142$^{\circ}C$ for emergence, 683-756$^{\circ}C$ for heading, and 1274-1326$^{\circ}C$ for maturity. In general, the accumulated temperature to heading was higher in Saechalssalbori than in Sacheon #6 because the winter growth habit of Saechalssalbori was not removed perfectly, One-thousand grain weight and yield were reduced by delayed seeding. In order to reduce the yield when barley were planted in spying, it is desirable to select the spring type varieties, and to plant them as early as possible.

• Korean Journal of Weed Science
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• v.30 no.4
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• pp.396-404
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• 2010

Phenolic compounds, which are products of secondary metabolism, have been demonstrated to be widespread growth substances in plants. The objectives of this study were to identify the phenolic compounds in common ragweed (Ambrosia artemisiifolia var. elatior) by HPLC and to evaluate their effects on germination and seedling growth of three weed species. Under controlled conditions in Petri dishes at $25^{\circ}C$, $10^{-3}$ and $10^{-4}$ M solutions of phenolic compounds were evaluated in seed germination tests. Four phenolic compounds (caffeic acid, O-coumaric acid, ${\rho}$-coumaric acid and ferulic acid) in common ragweed plant were identified and their concentration was increased from the stage before flowering through full flowering stage. Treatment of O- and ${\rho}$-coumaric acids delayed the seed germination of Digitalia ciliaris, while the treatment of caffeic acid delayed the seed germination of Echinochloa crus-galli. In time to 50% germination ($T_{50}$), phenolic compounds at $10^{-4}$ M promoted in Cyperus microiria and E. crus-galli but the level of $10^{-3}$ M delayed the $T_{50}$ of those weeds. The O-coumaric acid inhibited seed germination and seedling growth of the tested weeds and especially it perfectly inhibited the root growth of E. crus-galli.

• Tunnel and Underground Space
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• v.24 no.1
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• pp.67-80
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• 2014

Long-term stability and delayed failure of granite were evaluated through the laboratory test based on Wilkins method and Brazilian disc test (BDT) which yields tensile strength, mode I fracture toughness and subcritical crack growth parameters. Then, the long-term strength of granite was estimated by using analytical models and long-term stability of compressed air-energy storage (CAES) pilot cavern pressurized up to 5 ~ 6 MPa was evaluated using numerical code, FRACOD with the determined subcritical crack growth parameters. The results of test and analyses showed that the subcritical crack growth index, n was determined as 29.39 and the inner pressure of 5 ~ 6 MPa had an insignificant effect on the long-term stability of pilot cavern. It was also found that the measurement and analysis of acoustic emission events can describe the accumulation of damage due to subcritical crack growth quantitatively. That is, AE monitoring can provide the current status of rock under loading if we make an identical installation condition in the field with that of the laboratory test.

• Journal of The Korean Society of Grassland and Forage Science
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• v.2 no.2
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• pp.16-20
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• 1981

To cultivate Dystaenia takesimana as a fodder crop, Its problems and solutions are summarized follows : 1. There are a wax layer and wings on the out side of seed coat of D. takesimana seeds, which seems to inhibit imbibition and cause delayed germination. 2. The root and shoot growth of D. takesimana are very poor in the early stage and weed control is quite troublesome. 3 The growth of D. takesimana is very poor the soil of low fertility and much depressed in summer. 4 . The percent germination could be increased by removing wings, soaking, high temperature treatment or by chemical scarification. 5. Compost is most effective for the growth of D. takesimana and lime dressing is desired in the soil of low pH. 6 . The seedling growth could be improved selecting and breeding the strains with better germination and root growth, at the germination and growth characteristics of D. takesimana are variable.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.4
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• pp.82-89
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• 2012

In order to clarify the effect of overload on crack growth behaviors, fatigue tests for overload were carried out for round plain specimens of SM45C steel. In the experiment, typical semi-elliptical crack shape was found and further crack growth behaviors were tested. Using three types of single overload fatigue tests, Crack growth retardation phenomenon were examined. The growth rate of surface crack(da/dN) during retardation period was analyzed in terms of ${\Delta}K$ and ${\Delta}K_{eff}$. On the growth rate of surface crack analyzed by ${\Delta}K$, the dependence of overload stress levels appears. However, on the growth rate by ${\Delta}K_{eff}$ obtained by Willenborg analysis, there is a liner relationship between da/dN and ${\Delta}K_{eff}$ with narrow scatter band.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.3
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• pp.343-348
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• 2015

Soybean is one of the important food crop around the world. Especially in East Asia, it is the main ingredient for traditional food like soy sauce and soy paste. The double cropping system including soybean following onion, Chinese cabbage, and potato is widely adopted in Southern region of Korea. In this system, sowing date of second crop (soybean) can be delayed depending on first crops' growth period and weather condition. When planting date is delayed it is known that soybean yield is declined because of shorter vegetative growth period and earlier flowering induced by warm temperature and changes in photoperiod. The objective of this study was to determine soybean growth and yield responses as plant populations at late planting date. Field experiment was conducted at Department of Functional Crop, National Institute of Crop Science, RDA located in Miryang, Gyeongsangnam-Do for two years ('13-'14) in upland field with mid-late maturity cultivar Daewon. A split-plot block design was used with three replications. Main plots were three sowing dates from June 20 to July 20 with 15 days intervals, and subplots were 4 levels of planting densities. Data of maturity (R8) was recorded, yield components and yield were examined after harvesting. Experimental data were analyzed by using PROC GLM, and DMRT were used for mean comparison. Optimum planting population for maximizing soybean yield in late planting which compared with standard population. In mid-June planting, higher planting density causes increased plant height and decreased diameter which lead to higher risk of lodging, however, reduced growth period due to late planting alleviated this problem. Therefore higher seeding rates can provide protection against low seedling emergence caused by late planting in this region.

• Journal of Korean Academy of Nursing
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• v.15 no.3
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• pp.62-73
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• 1985

The problems of growth & development due to maladjustment are gradually increasing while need for the treatment of children's diseases is decreasing. The level of developmental deficiency or delay correlates with neonatal birth weight and also with gestational age, i.e. degrees of prematurity. There-fore, developmental defects and potential risk factors' are more Common in premature infants than in full term infants. The purpose of this study is to define the difference in the growth at developmental status between premature and full term infants, and to define the relation between the developmental status and the physical growth during the first 3 years' Data were collected from January 10, 1985 to April 6, 1985 at 3 hospitals including St. Mary's Hospital, and through home visiting. The subjects of this study consisted of 79 Premature infants (G.A. <37wks. & B.W. <2.5kg) and 94 full term infants (G.A.≥37 wks. & B.W.≥2.5kg). The study method used was a questionnaire, anthropometric assessment and DDST for normative data of growth & development. The collected data were analyzed using descriptive statistics, chi-square test and t-test. The results of the study were as follows: Hypothesis: 1 : That the prematures will differ from the full term infants in the physical growth status during the first 3 years was partially supported (p＜0.02) : The prematures reached up the full term infants in the physical growth status in the first 6 months. And, the first hypothesis was supported (P<0.01) : There are more cases which is below‘the Korean children's physical. growth standards’in prematures than in full term infants. Hypothesis 2 : That the prematures will differ from the full term infants in the developmental status during the first 3 years was supported (P< 0.001)；‘Normal’developmental status due to DDST was less in prematures than in full term infants. And, the second hypothesis was Partially supported (P<0.02) : The developmental status of the pre-matures was different from that of the full term infants within the first 3 months by analysis of passed items in DDST, Hypothesis 3 : That the prematures' developmental status will relate to their physical growth during the first 3 years was supported (P<0.001) : If the prematures' developmental status is in delayed status, then, their physical growth status is also in delayed status. This study shows that the prematures differed significantly from the full term infants in the growth at developmental status during their infancy. This means that the nurse can foster the growth & development of the prematures by supportive care during their infancy. Further longitudinal study is needed to verify these findings for the environmental factors.