• Title, Summary, Keyword: Growth

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A Study on the Morpholgies and Mechanical Properties of Sn-Zn Eutectic Alloys (Sn-Zn 공정합금(共晶合金)의 응고속도(凝固速度)에 따른 조직(組織)과 기계적(機械的) 성질(性質)에 관한 연구(硏究))

  • Lee, J.H.;Lee, K.W.
    • Journal of Korea Foundry Society
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    • v.5 no.4
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    • pp.258-270
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    • 1985
  • The structures and mechanical properties of undirectionally solidified Sn-Zn eutectic alloys have been examined over the growth range 7mm/h to 6,000mm/h. The structures of unidirectionally solidified Sn-Zn eutectic alloys were primarily broken-lamellar at growth rates below 760mm/h and became fibrous at higher growth rates above that. At a growth rate 3,084mm/h the structures were fibrouse only. There is no dendrites at any growth rates, but occasionally ribbon-like morphologies were seen. The under cooling increased parabolically with growth rate increase. The hardness of specimes increased with growth rates increase but heat-treated specimen decreased after growth rates 760mm/h and became constant value. The effect of heat-treatment was good at lower growth rate. At room temperature tensile strength increased with growth rates up to R=990mm/h and then tensile strength became near-constant value. The effect of heat-treatment was well at lower growth rate.

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Growth rate and growth steps of 6H-SiC single crystals in the sublimation process

  • Kang, Seung-Min;Lim, Chang-Sung;Auh, Keun-Ho
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.11 no.4
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    • pp.166-169
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    • 2001
  • 6H-SiC bulk crystals were grown by sublimation method with different conditions in term of gaseous pressures ad source temperatures. In order to optimize the growth rate, pressure at growth period and source and substrate temperatures were investigated as experimental variables. the results were compared with each other and finally the optimum growth conditions were discussed. Furthermore the relation of the growth steps and defects formation was evaluates in the point of reducing the micropipes. Subsequently the growth steps and defects formation was evaluated in the point of reducing the micropipes. Subsequently the growth steps were observed leading to the lower step height with the lower growth rate.

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Mechanism of Growth Hormone Action : Recent Developments - A Review

  • Sodhi, R.;Rajput, Y.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.12
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    • pp.1785-1793
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    • 2001
  • The interaction of growth hormone with it's receptor results in dimerization of receptor, a feature known in action of certain cytokines. The interaction results in generation of number of signalling molecules. The involvement of Janus kinases, mitogen activated kinases, signal transduction and activator of transcription proteins, insulin like substrate, phosphatidylinositol 3-kinase, phospholipase C, protein kinase C is almost established in growth hormone action. There are still many missing links in explaining diversified activities of growth hormone. Amino acid sequence data for growth hormones and growth hormone receptors from a number of species have proved useful in understanding species specific effects of growth hormone. Complete understanding of growth hormone action can have implications in designing drugs for obtaining desired effects of growth hormone.

A Study of Vision Algorithm Development for Growth Monitoring of Potato Microtubers (인공씨감자 생육상태 모니터링을 위한 화상처리 알고리즘 개발에 관한 연구)

  • Choi, J.W.;Chung, G.J.;Lim, S.J.;Choi, S.L.;Chung, H.;Nam, H.W.
    • Journal of Biosystems Engineering
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    • v.23 no.4
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    • pp.373-380
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    • 1998
  • The contribution of this paper is to provide the methods for the production automation of potato microtuber using the vision process in growth monitoring. The first method deals with computation for the growth density in the primary growth process. The second method addresses cognition process to identify the number and the volume of potato microtuber in secondary growth process. The third is to decide whether potato microtubers are infected by a virus or bacteria in growth process. The computation for the growth density in the primary growth process uses the method of Labeling. The second and third methods use template matching based on color patterns. With the developed method using vision process, this experiment is capable of discriminating weekly growth-rate in primary growth process, 85% cognition rate in secondary process and identifying whether there are infections. Therefore, we conclude that our experimental results are capable of growth monitoring for mass production of potato microtubers.

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Investigation of carbon nanotube growth termination mechanism by in-situ transmission electron microscopy approaches

  • Kim, Seung Min;Jeong, Seojeong;Kim, Hwan Chul
    • Carbon letters
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    • v.14 no.4
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    • pp.228-233
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    • 2013
  • In this work, we report in-situ observations of changes in catalyst morphology, and of growth termination of individual carbon nanotubes (CNTs), by complete loss of the catalyst particle attached to it. The observations strongly support the growth-termination mechanism of CNT forests or carpets by dynamic morphological evolution of catalyst particles induced by Ostwald ripening, and sub-surface diffusion. We show that in the tip-growth mode, as well as in the base-growth mode, the growth termination of CNT by dissolution of catalyst particles is plausible. This may allow the growth termination mechanism by evolution of catalyst morphology to be applicable to not only CNT forest growth, but also to other growth methods (for example, floating-catalyst chemical vapor deposition), which do not use any supporting layer or substrate beneath a catalyst layer.

Efficient Procedural Modeling of Trees Based on Interactive Growth Volume Control

  • Kim, Jinmo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.9
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    • pp.2232-2245
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    • 2013
  • The present study proposes efficient procedural modeling methods for enabling the growth and creation of various trees with minimal user control. Growth volume algorithms are utilized in order to easily and effectively calculate many parameters that determine tree growth, including branch propagation. Procedural methods are designed so that users' interactive control structures can be applied to these algorithms to create unique tree models efficiently. First, through a two-line-based interactive growth volume control method, the growth information that determines the overall shape of the tree is intuitively adjusted. Thereafter, independent branch control methods designed to control individual branches are added to the growth deformation in order to enable the growth of unique trees. Whether the growth processes of desired trees can be easily and intuitively controlled by the proposed method is verified through experiments. Methods that can apply the proposed methods are also verified.

A STUDY ON THE BODY HEIGHT AND WEIGHT OF STUDENTS IN SEOUL (서울 지역 학생의 신장 및 체중에 관한 연구)

  • Zun, Kee Hwan
    • The korean journal of orthodontics
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    • v.4 no.1
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    • pp.31-40
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    • 1974
  • The age of maximum growth increments-the adolescent spurt-is not only of developmental interest but is used as a marker for timing other growth events. And the mandibular growth rate follows the general growth curve, it is essential for an orthodontist to take the current and exact information about physical growth of patients. The author measured and studied the body height and weight of 11,694 children living in Seoul, and calculated out the mean, standard deviation, coefficient value, annual increments, percentage increments of each value, and made diagram to compare it with others. 1. The growth curve shows linear increment tendency until 17 years of age in male, 15 years in female. 2. The annual increment curves of body height and weight reveals the most peak value in 14-16 years in male and 11-14 years in female. 3. During 11-14 years of age, female growth exceed the male growth in the body height growth. And in weight growth, female growth exceed the male growth during 6-7 years and 11-12 years to show twice crossing. 4. It seemed that until 11-12 years in male and until 9-10 years in female the height growth show the priority to weight growth. And from 17 years in male and 15 years in female the body growth reveals the balanced growth pattern. 5. The time of changes of standard deviation curves of body height and weight coincided with that of annual increments. 6. The prominent high value of body height and weight in the comparison with other data may be due to the secioeconomical and nutritional, environmental influence. 7. The growth accerlation phenomena was detectable.

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Regeneration Process after Disturbance of the Pinus densiflora Forest in Korea (한국 소나무림에서의 교란 후 재생과정)

  • Lee, Chang-Seok
    • The Korean Journal of Ecology
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    • v.18 no.1
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    • pp.189-201
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    • 1995
  • In order to clarify regeneration processes and mechanisms of the disturbed Pinus densiflora forest, responses of Pinus densiflora to gap formed by disturbance were analysed by growth of saplings and mature and growth equations were obtained from branch growth of mature trees and height growth of saplings, and age distribution of saplings and young trees recruited within gap was analysed in relation to gap age. Height growth of saplings within gaps was accelerated after gap formation. Such abrupt increases of growth of saplings after the gap formation might be resulted in the difference of growth of saplings between gap and non-gap areas. In fact, height and diameter of saplings in the central part of gap were larger than those of saplings in marginal parts of gap and non-gap area. However, density of saplings was not different in both parts. In addition, growth of annual rings of mature trees bordering on gap also increased after gap formation. Branch growth of mature trees bodering on gap was 6.3 - 6.5 cm /year and the mean radius of gaps created by death of only one canopy tree was about 3 m. Therefore, for those gaps to be closed by branch growth it will take 46 years. Growth of saplings within gap showed exponential equation. Fifty years will be required for the saplings to enter the forest canopy by the exponential growth equation. Therefore, gap created by only one tree might be closed by branch growth of surrounding canopy trees in advance of being done by height growth of saplings. But gaps created by death of trees more than 2 will be closed by the growth of saplings. Among the regenerating saplings and young trees within gaps, individuals established in advance of gap formation were more than those established after the gap formation. From these results, it was assumed that the disturbed Pinus densiflora forests in these sites were regenerated by height growth of saplings recruited in advance of gap formation.

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Growth Responses of Lettuce Seeds Germinated in Aqueous Solutions of Sulfur Dioxide (아황산 수용액에서 발아시킨 상치 종자의 생장반응)

  • 이미순
    • Journal of Plant Biology
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    • v.18 no.4
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    • pp.155-160
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    • 1975
  • Growth responses of lettuce seeds germinated in aqueous solutions of $SO_2$ were investigated for mode of action studies of this gas. The concentration and pH of $SO_2$ solution greatly affected the growth of germinating seeds. Root growth was more sensitive to $SO_2$ than hypocotyl growth. The sensitivity of total seedling growth lay between root and hypocotyl growth. Growth inhibition of germinating seeds appeared more serioius when $SO_2$ was added during the early stage of germination.

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Modeling of Typical Microbial Cell Growth in Batch Culture

  • Jianqiang Lin;Lee, Sang-Mok;Lee, Ho-Joon;Koo, Yoon-Mo
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.5 no.5
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    • pp.382-385
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    • 2000
  • A mathematical model was developed, based on the time dependent changes of the specific growth rate, for prediction of the typical microbial cell growth in batch cultures. This model could predict both the lag growth phase and the stationary growth phase of batch cultures, and it was tested with the batch growth of Trichoderma reesei and Lactobacillus delbrueckii.

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