• 아동학회지
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• 제33권3호
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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.

• 생약학회지
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• 제1권1호
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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%.

• 한국자원식물학회지
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• 제12권1호
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• pp.27-30
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• 1999

야생 약초인 세신의 재배년수별 생육특성과 수량성을 구명하고 주요 정유 성분인 methyleugenol과 safrole함량 변화를 조사하여 세신의 상품적 가치를 높이고 품질의 규격화를 위한 기초자료를 얻고자 1993년부터∼1997년까지 5년간에 걸쳐 시험을 실시하였던 결과를 요약하면 다음과 같다. 1. 재배년차별 생육은 재배년수가 경과함에 따라 지하부 생육의 신장차이가 크게 나타났으며 특히 근장의 크기에 따라 수량변화에 영향을 미쳤다. 2. 10a당 건근 수량은 3년재배(127kg/10a)에 비하여 4년재배 191%, 5년재배 259% 순으로 증수되었다. 3. 재배기간별 정유함량은 재배 기간에 따라 3년 5%, 4년 4.5%, 5년은 4.3% 순이었다. 4. 주요 정유 조성성분인 methyleugenol은 재배년수가 길어질수록 증가하였으나 safrole함량은 점차 감소하여 methyleugenol과 safrole 함량은 서로 상반된 관계를 나타내었다.

• 한국식품과학회지
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• 제9권1호
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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.

• 아동학회지
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• 제31권4호
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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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• 제12권3호
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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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• 제3권1호
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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.

• 아동학회지
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• 제31권6호
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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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• 제31권3호
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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.

• 한국약용작물학회지
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• 제27권6호
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• pp.383-389
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• 2019

Background: Ginseng has been used as a medicine and functional food since ancient times. It is a perennial crop, and its whose commercial valuse increases with growing period and is affected by the atmosphere and soil environment. Methods and Results: In a selected field, we measured air temperature under a shade structure and soil physicochemical properties, and determied plant and root growth as well as ginsenoside and total polyphenol content of one- to five-year-old ginsengs plants. Although air temperature above 30℃ was recored for more than 37 days, no marked growth inhibition of ginseng was detected. Among all soil physicochemical properties, except for pH, were within the allowable range the shortage increases with ginseng years. In five-year-old ginseng, the quantity is about 9.7% higher than the average weight by standard, indicating that is not affected by temperature when grown under a shade structure. Three-year-old ginseng contained the highest total ginsenoside and total polyphenol levels and exhibited the greatest DPPH radical scavenging activity. Conclusions: The total ginsenoside and protopanaxadiol/protopanaxatriol ratio were both low at five-year-old ginseng plants, which was attributed to rapid growth of the root system in five-year-oid plants. There were no significant differences in total polyphenol content and antioxidant activity between.