• Title/Summary/Keyword: day length

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Seasonal Changes in Jasmonic Acid Contents of Yam Leaves

  • Chang, Kwang-Jin;Mitsuru Hayashi;Michilo Onjo
    • Plant Resources
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    • v.1 no.1
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    • pp.49-52
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    • 1998
  • This study confirmed that the initiation time of tuberization was well consistent with the cativation time of JA. The consistency was also cinfirmed in the tuberization of yam plants under the altered condition of natural day length. The final yield of JA from 500g fresh leaves was $89.3{\mu}g$.

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Observational Arc-Length Effect on Orbit Determination for Korea Pathfinder Lunar Orbiter in the Earth-Moon Transfer Phase Using a Sequential Estimation

  • Kim, Young-Rok;Song, Young-Joo
    • Journal of Astronomy and Space Sciences
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    • v.36 no.4
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    • pp.293-306
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    • 2019
  • In this study, the observational arc-length effect on orbit determination (OD) for the Korea Pathfinder Lunar Orbiter (KPLO) in the Earth-Moon Transfer phase was investigated. For the OD, we employed a sequential estimation using the extended Kalman filter and a fixed-point smoother. The mission periods, comprised between the perigee maneuvers (PM) and the lunar orbit insertion (LOI) maneuver in a 3.5 phasing loop of the KPLO, was the primary target. The total period was divided into three phases: launch-PM1, PM1-PM3, and PM3-LOI. The Doppler and range data obtained from three tracking stations [included in the deep space network (DSN) and Korea Deep Space Antenna (KDSA)] were utilized for the OD. Six arc-length cases (24 hrs, 48 hrs, 60 hrs, 3 days, 4 days, and 5 days) were considered for the arc-length effect investigation. In order to evaluate the OD accuracy, we analyzed the position uncertainties, the precision of orbit overlaps, and the position differences between true and estimated trajectories. The maximum performance of 3-day OD approach was observed in the case of stable flight dynamics operations and robust navigation capability. This study provides a guideline for the flight dynamics operations of the KPLO in the trans-lunar phase.

A Study on the Distance Ratio between Apartment Houses for Sunshine Time of Apartment Houses (focused in Seoul metropolitan city and six metropolitan cities) (공동주택(共同住宅)에서 일조시간(日照時間)에 따른 인동거이비(隣棟距離比)에 관한 연구(硏究) (서울특별시 및 6대 광역시 중심으로))

  • Lee, Hyang-Rim;Son, Cheol-Soo
    • Journal of the Korean housing association
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    • v.17 no.5
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    • pp.39-46
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    • 2006
  • This study was conducted in seven metropolitan cities in south korea containing Seoul and Busan etc and used DevC++ language program in the process to get datas of the distance ratio between apartment houses by the length of time accepting sunshine during the day time. Basically by inputting information such as a certain date, longitude, latitude etc, it was possible to get outputs of the length of shadow. This study obtained the data from the model experiment and computer programs which analysis of the sunshine environment. As mentioned above, by analysing relations between sunshine-ralated laws in each cities and those influential factors, it is possible to suggest the fundamental data of distance ratio between apartment houses when designing a new building with more optimized way.

The Development of Preschoolers′ Narrative Competence (3, 4, 5세 유아의 이야기 구성능력 발달)

  • 한유진;유안진
    • Journal of the Korean Home Economics Association
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    • v.39 no.7
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    • pp.71-84
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    • 2001
  • The purpose of this study was to investigate the development of preschoolers'narrative competence. The subject were 60 preschoolers aged 3 through 5 years who were enrolled in the day care center All the subjects were asked to produce a new story. All the story children toad were recorded on audiotape. The data were analyzed Qualitatively and quantitatively using content analysis and the statistical package for Social Science 9.0. The main results of this study were as follows. 1) Significant age difference was observed in preschooler's narrative structure. Older children produced structurally more complex stories containing setting, character, initiating event, attempt and consequence than younger children. 2) Significant age difference was observed in preschooler's narrative length. Older children used significantly more words and sentence when they produced stories than younger children.3) Preschooler'narrative structure was significantly correlated with narrative length.

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Studies on the Response to Day-length and Temperature and their Effects on the Yield of Perilla (Perilla ocimoides L.) (들깨의 일장 및 온도에 대한 감응성과 그의 수량에 미치는 영향에 관한 연구)

  • Ik-Sang Yu
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.17
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    • pp.79-114
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    • 1974
  • Experiments were conducted to clarify the variations of the ecological characteristics under different day-length and temperature conditions inperilla varieties from 1972 to 1973 in the experimental fields of Crop Experiment Station, O.R.D, Suwon. Thirty-six varieties were tested in the field in 1972 under 6 growing seasons differing seeding dates. from April 5th to June 20th with 15-day interval between each seeding. Pot-experiment also were conducted in 1972 and 1973. The seeds of the 6 varieties tested were sown on May 25th. In this pot-experiment natural condition was regarded as a short-day treatment and 100-W incandescent lamps were used for long-day treatment. Three selected varieties were grown under different. temperature treatments in phytotron in Crop Experiment Station. The results obtained are summarized as follows: 1. Most varieties tested flowered around September 6. The days required to flower were shortened gradually as the planting time was delayed. 2. The varieties used were matured around October 6, but the maturity was shortened when planted early. The days required for maturity after flowering was 26 to 30. 3. The growing period was also shortened gradually when planting time was delayed. 4. Plant height was reduced when planting time was delayed. 5. There were little differences in number of valid branches among planting time I, II and III, while the branch number was reduced as the planting time was delayed. 6. The dry matter weight was gradually increased from planting time I to III, while it was rapidly decreased after planting time IV. 7. It was found that the flowering of perilla was little affected by temperature. The varieties, however, were more sensitive to day-length. 8. No clear tendency was found in the plant height, number of valid branches and dry matter weight by the time and period of day-length and temperature treatments. 9. The highest yield was obtained at planting time III(May 5th) and the yield was decreased at either earlier or later planting. 10. 1, 000 grain weight appeared to be heavier as the planting time was delayed. 11. The number of flower cluster was largest at planting time III (May 5th) and it was decreased as planting time was earlier or later than III. 12. The oil content was also highest at planting time III (May 5th). 13. Days to flowering, days to maturity and total growing period and flowering period did not affect the yield much. 14. The number of valid branches, flower clusters, 1, 000-grain weight and dry matter weight were positively correlated with yield. The relationship between these characters and yield were variable depending upon the planting time.

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EXPRESSION PATTERN OF RUNX2 IN MURINE TOOTH DEVELOPMENT (Mouse의 치아 발육시 Runx2의 발현 양상)

  • Kim, Tae-Wan;Ryoo, Hyun-Mo;Nam, Soon-Hyeun;Kim, Young-Jin;Kim, Hyun-Jung
    • Journal of the korean academy of Pediatric Dentistry
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    • v.31 no.4
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    • pp.651-658
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    • 2004
  • Runx2 is a transcription factor in homologous with Drosophila runt gene and it is essential for bone formation during embryogenesis and a critical gene for osteoblast differentiation and osteoblast function. Runx2-haploinsufficency causes cleidocranial dysplasia (CCD). CCD is an autosomal-dominant inherited disorder characterized by hypoplastic clevicle and delayed ossification in fontanelles and wormian bones. Dental defects are possibly shown to CCD patients : multiple supernumerary teeth, irregular and compressed permanent tooth crowns, hypoplastic and hypomineralized defects in enamel and dentin, an excess of epithelial root remnants, the absence of cellular cementum, and abnormally shaped roots. In addition, delayed eruption of the secondary dentition is a constant finding. The aim of this study is to evaluate the role of Runx2 in the tooth development and eruption through analyzing the expression pattern of Runx2 by in situ hybridization during crown (late bell stage) and root formation of tooth, using postnatal day 1, 4, 7, 14 and 21 mice mandibular molar teeth. mRNA of Runx2-full length is expressed in dental follicle and surrounding tissue at postnatal day1 and 4. At postnatal day 7, it is expressed in ameloblasts of occlusal surface of enamel and bone area surrounding the tooth. In comparison with previous stage, at postnatal day 14, it is expressed in ameloblasts of proximal surface of enamel. At postnatal day 21 it's expression is observed only in bone area. mRNA of Runx2-typeII is not expressed. At postnatal day 1 and 7. At postnatal day 14 and 21, it's expression is observed in the bone area. In this study, we suggest that Runx2 have a relation of ameloblasts differentiation and an important role to tooth eruption made by dental follicle during intraosseous eruption stage. Also we can confirm that Runx2 has a role to bone formation.

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