• Korean Journal of Child Studies
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• v.33 no.3
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• pp.131-148
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• 2012

This study examines the scientific concept development of young children in terms of the day-night cycle. The subjects consisted of 180 three-, four-, and five-year-old children from two kindergartens and one children's center located in Seoul and Jeju. Individual interviews were conducted to collect verbal and pictorial responses on the day-night cycle. The scientific concepts on the day-night cycle are classified five stages including : no recognition, egocentric concept, initial mental models, synthetic mental models, and scientific mental models. Using two-way ANOVA, scores for the types of concept on the day-night cycles were then analyzed according to both the ages and genders of the children. The results reveal the existence of significant differences in terms of the types of concept of young children according to age. Most three-year-olds children had no recognition. Most three, four, and five-year-old children revealed egocentric concepts. Four-year-old children revealed that were in the initial stages of experiencing the mental models and synthetic mental models of the day-night cycle. Five-year-old children revealed that they were in the early stages of experiencing the initial, synthetic, scientific mental models of the day-night cycle. The results suggest appropriate ways of science education for young children based on the development of scientific concepts of the day-night cycle.

• Korean Journal of Pharmacognosy
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• v.1 no.1
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• pp.33-34
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• 1970

The cultivation of Italian liquorice root was carried out and the three-year-old roots of average wet weight 800g were harvested. In early April the cut root was transplanted and the rate of survival was $50{\sim}60%$. The treatment of it with dilute Atonic solution increased the rate to 96%. The glycyrrhizin content in the root was: five-year-old root 7%, four-year-old 7.5%, three-year-old 6.7%, and two-year-old 4.7%.

• Korean Journal of Plant Resources
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• v.12 no.1
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• pp.27-30
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• 1999

This experiment was conducted to investigate the change of root yield and essential oil contents by cultivated year in Asaram siebold Mio. Growth of aerial part such as plant height, leaf length and leaf width increased rapidly in two to three-year-old. Root length and root weight per plant were increased as cultivation year passed. Especially the speed of development was very fast in two and three-year-old alike aerial part. Root yield was the highest at five-year-old. The content of essential oil was decreased gradually as cultivation year passed. Methyleugenol content was increased, while safrole content was decreased by cultivated years. The increasing of methyleugenol content in four to five-year-old was not higher than three to four-year-old. In the result, it concluded that the optimum harvest time of Asarum sieboldi MiO is five-year-old cultivated based on root yield and effective medical components.

• Korean Journal of Food Science and Technology
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• v.9 no.1
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• pp.19-23
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• 1977

The variation of the amount of starch, size and shape of the starch granules, amylose content, and blue value of the starch in the Korean ginseng roots from one year old to five year old cultivated at Kumsan was studied. The results obtained were as follows; 1) The starch content of the ginseng root(dried) was increased with the age of the root; that is, 9.62% for one-year-old roots, 10.35% for two-year-old root, 15.50% for three-year-old root, 17.05% for four-year-old root, and 18.32% for five-year-old root. 2) The shape of the ginseng starch granules was round or short oval, and in the latter case the ratio of minor axis to major axis was 1 to 1.1. Diameter of the starch granules was in the range of $1.48\;{\mu}\;to\;8.14\;{\mu}$ and the most frequent granule size was $3\;{\mu}\;(32.1{\sim}35.7%)$. The number of big size starch granules was increased during the five years of growing, while, the number of small size granules was decreased. 3) The amylose content in the ginseng starch was varied with the age of the root, in the range of $53.6{\sim}70.5%$. 4. The blue value of the ginseng starch was in the range of 0.60 to 0.71.

• Korean Journal of Child Studies
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• v.31 no.4
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• pp.49-60
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• 2010

This study sought to investigate and assess the development patterns of children, aged from 3 to 5, by means of a longitudinal approach. The children's developmental patterns are classified according to five curriculum areas; physical health, social skills, expression, language, and exploration-. The developmental patterns are analyzed in detail according to the observation period, children's ages, and their genders. The subjects consisted of 108 children in A city. A research assistant was asked to observe and keep records of the children's behaviors at three distinct times -early, middle, and late in the school year. The 'observational scale for children' was used as the measurement tool. The data which was thus collected was then subject to statistical analysis. The major findings of the study are as follows. First, there were significant differences in all five curriculum areas according to the children's age and observation period. That is, five-year-old children showed higher scores than three- and four-year-old children. Second, there were significant differences in the social development within five curriculum areas according to the children's gender and the observation period. That is, girls exhibited higher scores than boys.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.3
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• pp.348-353
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• 1999

Ten Australian Stock Horses colts (five yearling and five 3-year old colts) of which 2 yearlings and 2 three year old colts served as control animals while 3 yearlings and 3 three year old colts received two GnRH immunizations within 4 weeks interval were used in this study. By the 5th to 6th week after immunization, the GnRH antibody titres in the plasma rose above 1:1000 and attained peak levels of 1:6500 by the 8th week and gradually declined to about 1:3000 by the 10th week in both the age groups. The testosterone and androstenedione concentrations of the control colts in both age groups were significantly greater (p<0.05) than that of the vaccinated groups. During the immunosuppression period, the vaccinated colts behaved like geldings. Semen could not be collected from 2 of the 3 three-year old vaccinated colts. The testicular dimensions, testicular weight, parenchymal weight, seminiferous tubule volumes, interstitial space volumes, Leydig cell volume, seminiferous tubule % of the control colts were significantly greater than those of the vaccinated colts in both the age groups. The 3-year old control colts had a significantly (p<0.05) greater % of Leydig cells than the control and vaccinated 1-year old colts. There was arrest of spermatogenesis with complete absence of sperm in the testes of the vaccinated colts while there was various stages of spermatogenesis in those of the control colts. Morphometric analysis demonstrated that the 3-year old colts had significantly (p<0.05) greater DSP/gm of testis and DSP/testis than those of the 1-year old control colts. This study elucidated that the GnRH immunization could suppress the testicular function of the 3-year old and yearling colts.

• Earthquakes and Structures
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• v.3 no.1
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• pp.83-95
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• 2012

Seismic damage and vulnerability of five historical masonry structures surveyed after the 1999 Kocaeli and Duzce, Turkey earthquakes are discussed in this paper. The structures are located in two neighboring cities that have been struck by five very large ($M_s{\geq}7.0$) earthquakes during the $20^{th}$ century alone. Older masonry mosques with arches and domes and their masonry minarets (slender towers) were among the most affected structures in this highly seismic region. While some of the religious and historical structures had virtually no damage, most structures suffered significant damage or collapsed. In the city of Bolu, for example, approximately 600-year-old Imaret, 500-year-old Kadi, 250-year-old Sarachane, and 100-year-old Yildirim Bayezid mosques suffered substantial structural damage after the 1999 earthquakes. Another historical mosque surveyed in Duzce partially collapsed. Most common factors contributing to deterioration of historical structures are also presented. Furthermore, a brief overview of issues associated with analysis and modeling of historical masonry structures is provided.

• Korean Journal of Child Studies
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• v.31 no.6
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• pp.153-166
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• 2010

The purpose of this study was to examine Korean young children's acquisition of honorific expressions. The participants of the present study were 297 young children (ages 3-5 years) from Kyunggi province. The results of the study showed that young children acquire honorific markers in the order of hearer-honorific expressions, subject-honorific expressions, and then object-honorific expressions. Five-year old children acquired at least 75% of the hearer-honorific expressions. The result can be explained by the fact that most of them were used in greetings. Even though more than 90% of five-year old children acquired the subject-honorific marker si, the acquisition rates of subjecthonorific nouns and subject-honorific verbs were less than 10%. Finally, the acquisition rates of objecthonorific expressions were less than 20%, with the exception of the object-honorific noun ce. The results of the study suggest that educational programs should be developed in order to facilitate the acquisition of honorific markers in young children.

• Journal of Plant Biology
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• v.31 no.3
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• pp.169-185
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• 1988

Vessel elements in lateral root, tap root, transition region, stem and mid vein of 1-year old, 3-year old and 5-year old ginseng (Panax ginseng C.A. Meyer) are studied with light microscope to clarify the distribution and differentiation of several kinds of vessel elements. Vessel elements are classified into five types such as ring vessel, spiral vessel, scalariform vessel, reticulate vessel and pitted vessel according to the secondary thickenings of cell wall. All of the five types are not observed in each organ, but diverse kinds of vessels are present in stem and mid vein compared with the underground organs such as tap root and lateral root. The length of vessel elements is longest (680$\mu$m) in stem and shortest (143$\mu$m) in tap root. The diameter of vessel elements is 19.0$\mu$m in tap root and the angle of perforation plate comes under 22$^{\circ}$-60$^{\circ}$. The degree of differentiation of vessel elements according to the length, diameter and angle of perforation plate of vessel elements is highest in tap root regardless of the age of ginseng. Three types of perforation plate such as scalariform, intermediate type of simple and scalariform, and simple perforation plate are observed. The vascular tracheids are characteristically observed in mid vein of 1-year old ginseng, and in transition region of 3 and 5-year old ginseng.

• Journal of Ginseng Research
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• v.25 no.2
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• pp.101-105
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• 2001

Identification of the age of ginseng root is very important in commercial market as well as in research field. However, any criterion abut it has not been clearly established yet. We studied to find a clear morphological key for identification of ginseng root\\`s age using the histochemical staining method. Fresh sections of 3, 4, 5, and 6 year old roots were stained with 1% nile blue, observed under the light microscopy, and compared each other. The number of secretory duct layers(SDL) is a useful key to confirm the age of ginseng root as follow; three-year-old root has two, four-year-old one has three, fie-year-old one has four, and six-year-old one has five resin duct layers on each cortical region of roots. Secretory ducts are thought to be formed by the vascular cambium every year. Unlike the surrounding parenchyma cells, secretory epithelial cells lack starch grains in the cytoplasm.