• 제목/요약/키워드: rapid growth

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강유전체게이트 전계효과 트랜지스터의 정보저장특성 향상을 위한 $SrBi_2Nb_2O_9$ 박막의 급속 결정성장방법 (Rapid Grain Growth of $SrBi_2Nb_2O_9$ Thin Films for Improving Programming Characteristics of Ferroelectric Gate Field Effect Transistor)

  • 이창우
    • 마이크로전자및패키징학회지
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    • 제12권4호통권37호
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    • pp.339-343
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    • 2005
  • Pt-$SrBi_2Nb_2O_9(SBN)-Pt-Y_2O_3-Si$ 게이트 전계효과 트랜지스터 (MFMISFETs)의 정보저장 특성향상을 위하여 SBN 박막을 산소 플라즈마 내에서 급속열처리 하였다. 그 결과 SBN 박막의 결정크기는 $700^{\circ}C$의 동일한 열처리조건에서 급속열처리한 SBN 결정립의 크기가 전기로 열처리에 의한 SBN 결정립보다 4배 이상 성장하였다. 또한 분극 특성을 비교한 결과 잔류분극은 2배이상 급속열처리 방법으로 제조된 SBN 박막을 이용한 MFMISFET의 메모리윈도우 (memory window)와 on/off상태의 정보저장특성(programming characteristics)은 월등히 향상되었다.

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Cultivation of Nostoc flagelliforme on Solid Medium

  • Su Jianyu;Jia Shiru;Qiao Changsheng;Kim Jung-Gyu;Hong Wan-Hae;Cho Ki-An;Choi DuBok
    • 환경생물
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    • 제23권2호
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    • pp.135-140
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    • 2005
  • In order to construct an artificial cultivation of Nostoc flagelliforme on solid medium, we attempted to assess the viability of approaches, which utilized either BG-11 agar or sand medium using both sterile and non-sterile algal segments. In the trial in which the BG -11 agar medium was inoculated with the non-sterile algal segments, the algae exhibited the rapid growth in the initial 4 days of cultivation. However, after 4 days of cultivation, the growth rate of the algae slowed, and the algal growth was completely stopped by 7 days of cultivation. When the BG -11 medium was inoculated with the sterile algal segments, the algae exhibited the rapid growth for a longer period of 8 days, reaching a length of 24.9 mm. The growth rate during this period was measured to be $24.5\%$. After the 8 days of cultivation, the algal growth rate began to slow and had almost stopped by the 13 days of cultivation. On the other hand, when the sterile algal segments were inoculated onto a sand plate, the algal segments decomposed, reaching total decomposition after 11 days of cultivation. By way of contrast, the desiccation treatment samples continued to grow for 14 days of cultivation. After 14 days of cultivation, the algae achieved a length of 26.1 mm, with a growth rate of $30.6\%$. Our results indicate that periodic desiccation may constitute an effective strategy for the prevention of algal decomposition.

Comparison of Yield and Growth Characteristics of Korean High Yielding Cultivars and IRRI's New Plant Type Rice Line

  • Lee, Byun-Woo;Ha, Jong-Ryuk
    • 한국작물학회지
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    • 제44권1호
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    • pp.59-63
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    • 1999
  • Yield and growth characteristics were compared for five rice cultivars; a new Tongil-type, so called "super-rice", Dasanbyeo, an old Tongil-type Milyang 23, two japonicas Dongjinbyeo and Ilpumbyeo, and a new plant type (NPT)line IR65600-27-1-2. The objective of this stusy was to clarify the high yielding capacity of Dasanbyeo in terms of growth characteristics. The average grain yield (9 t/ha) of Dasanbyeo was higher than that of Milyang 23 by ca. 9% that of japonicas by 20 to 30%, and that of NPT line by ca. 100%. The higher grain yield of Dasanbyeo was attributable not only to the greater dry matter production but also to the higher harvest index (HI). Dasanbyeo showed the greatest dry matter at harvest owing not only to the rapid leaf expan-sion at early growth stage and the resulting high LAI through the entire growth stage but also to the high NAR despite the high LAI. The rapid leaf expansion of Dasanbyeo at early growth stage seemed to be related in part to the profuse tillering capacity. HI was 0.53 in Dasanbyeo, 0,51 in Milyang 23, 0.41 in japonicas, and 0.35 in NPT line. Dasanbyeo was indebted for its higher HI to the relatively high grain filling ratio in spite of a much greater sink size than the other cultivars. Dasan had a greater source to sink ratio during grain ripening as measured by LAD/spikelet and dry matter production/spikelet which showed positove correlations with the grain ripening ratio. New plant type (NPT) line showed the lowest grain yield owing to the small sink size and the low grain filling ratio which seemed to have resulted from the abundant occurrence of weak-strength spikelets. The weak sink strength, in turn, seemed to have suppressed photosynthesis during the grain ripening stage.

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도서관장서의 폐기기준에 관한 고찰 (A Study on Welding Criteria of Library Collections)

  • 이은철
    • 한국도서관정보학회지
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    • 제9권
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    • pp.213-240
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    • 1982
  • Today, one of the major pressures that libraries have been facing is the rapid growth of publications. Due to the rapid growth of publications, libraries have been faced the shortage of stack as well as quality deterioration of library collections. Naturally, these disa n.0, ppointed the users and made the present library activities weak and inadequate. One of the desirable actions in remedying these problems is to weed library collections properly and regularly. Weeding methods used in libraries are derived from the judgement by subject specialists, from the examining the imprint date and the past use patterns of a volume. Among these methods, the past use patterns are highly predictive of the future use, and can be used to create meaningful weeding criteria. Since the libraries in Korea have emphasized on numbers of library collection in the past, the libraries have neglected weeding library collections. Now, we must turn our concern toward the weeding library collections, and the attitude of the library services to the users must change from passive to active.

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Rapid Propagation through Tissue Culture of Cudrania tricuspidata, Medicinal Plant

  • Lee, Cheul-Ho;Min, Ji-Yun;Jung, Ha-Na;Kim, Kyu-Sick;Choi, Myung-Suk
    • 한국약용작물학회지
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    • 제15권5호
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    • pp.315-318
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    • 2007
  • An effective rapid propagation method was established through in vitro cultures of the medicinal plant, Cudrania tricuspidata. In vitro plantlets were obtained from in vitro germinated seeds. The various levels of cytokinins (BAP, Kinetin and TDZ) were tested on multiple shoot formation from plantlets. BAP (1.0 mg/l) treatment induced highest number of multiple shoots. Single shoot cultures gave higher initial shoot numbers than 5 shoots per culture. Among the various culture media, the shoot elongation was optimal on 2 MS basal medium without growth regulators. The IAA (2.0 mg/l) treatment induced highest number of roots. IBA (2.0 mg/l) treatment more promoted in vitro root growth than other concentrations. Rooted shoots were transferred directly to small pots with an artificial soil and successfully acclimatized.

Preparation of composite particles by Rapid Expansion of Supercritical fluid Solutions and Release behavior

  • Ryu, Han-Won;Kim, Jung-Hwan;Kim, Young-Do;Shin, Kun-Chul
    • 한국결정성장학회:학술대회논문집
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    • 한국결정성장학회 1998년도 PROCEEDINGS OF THE 15TH KACG TECHNICAL MEETING-PACIFIC RIM 3 SATELLITE SYMPOSIUM SESSION 4, HOTEL HYUNDAI, KYONGJU, SEPTEMBER 20-23, 1998
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    • pp.117-121
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    • 1998
  • The Rapid Expansion of supercritical fluid Solutions (RESS) process was applied to particles coating. Experiments were conducted in a fluidized bed with an internal nozzle in the center of the reaction tube. Microcapsules (mean particle size : 49$\mu\textrm{m}$) prepared by spray drying method were used as the core particles. Supercritical CO2 solutions of paraffin were expanded through the nozzle in to the bed that was fluidized by air. Surface morphology prepared particles was observed by SEM. For the inspection of particle size change, particle size distributions were measured before and after coating. The releasing behavior of Mg2+ ions inspected by AA.

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Nanostructure Ceramics of Silicon Nitride Produced by Spark Plasma Sintering

  • Hojo, Junichi;Hotta, Mikinori
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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    • pp.323-324
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    • 2006
  • The nanostructure control of $Si_3N_4$ ceramics can be achieved by using fine starting powder and retardation of grain growth. The spark plasma sintering technique is useful to retard the grain growth by rapid heating. In the present work, the change of microstructure was investigated with emphasis on the particle size of starting powder, the amount of sintering additive and the heating schedule. The rapid heating by spark plasma sintering gave the fine microstructure consisting of equiaxed grains with the same size as starting particles. The spark plasma sintering of $Si_3N_4$ fine powder was effective to control the microstrucutre on nano-meter level.

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신흥공업국의 기초연구능력 축적과정의 특성에 대한 탐색연구 -한국 사례를 중심으로- (An Exploratory Research on the Accumulation of Basic Research Capability in the Newly Developing Countries)

  • 황혜란
    • 기술혁신학회지
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    • 제7권1호
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    • pp.42-63
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    • 2004
  • Recent trend of rapid growth in the basic research activities in East-Asian newly industrialized countries bring about the change in the world knowledge production structure. Particularly, Korea showed the changing patterns not only in the number of publication, but also in the aspect of structural change of basic research activities. The stylized facts of basic research activities in Korea can be summarized in three aspects; first, selective development patterns, second, reverse pattern of evolution, and finally, the rapid growth of basic research activities in major firms. This paper analyse the evolutionary patterns of basic research activities in empirical base and propose the policy implication for supporting basic research activity in newly industrializing countries.

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Global Service Innovation: A Case Study of Ajisen Ramen

  • CHO, Myungrae
    • The Journal of Asian Finance, Economics and Business
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    • 제8권3호
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    • pp.967-976
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    • 2021
  • This study aimed to investigate the mechanism by which service companies transfer their services overseas and create new value while interacting with local characteristics. A narrative analysis method was used in a case study of Ajisen Ramen, a Japanese service company that created a Japanese-style ramen restaurant, which experienced rapid growth in China. This study analyzed the restaurant as global service innovation and constructed a causal mechanism to explain the resulting rapid growth. In the pre-entry stage, the tangible value source core service facilitated its successful overseas transfer. In the post-entry stage, value source core service standardization and value sharing were interrelated and locally accepted factors. Knowledge of the local characteristics influenced the local storefront format that allowed contact with local customers. This local front format made it possible to offer local customers new value. The global service innovation mechanism developed through this study reflects a causal diagram that correlated the theoretical concepts of these events.

조선시대(朝鮮時代) 도작농업(稻作農業)의 발전(發展)과 인구증가(人口增加) (Rice Cultivation and Demographi Development in Korea : 1429-1918)

  • 이호철
    • Current Research on Agriculture and Life Sciences
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    • 제7권
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    • pp.201-219
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    • 1989
  • Rice culture in Korea has a long history ranging over two thousand years. In the agriculture economy of pre-mordern Korea, however, its importantce was not as great as generally assumed. In fact, rice culture reached full development only after the 1920s when the Japanese colonial government carried out its drive to increase rice production in the Korea peninsula. It was not until the mid-1930s that rice became the staple in Korean diet. This can be attributed to two factors : (1) a mountainous topography that provides little irrigated fields and (2) a climate characterized by droughts in spring and heavy precipitation in summer. The present paper attempts to answer some of these questions. Specifically it will focus on these : Did the development of rice culture actually result in population growth? What are the salient features of agricultural develdpment and population grow in traditional Korea? Does the case of Korea conform the prevailing generalization about the agriculture in East Asia? I have discussed the development of rice culture and population growth in the Chos$\breve{o}$n dynasty, focusing on the relation between the rapid spread of transplanting and the rapid growth of population from the seventeenth to the nineteenth century. Here are my conclusions. (1) The spread of transplanting and other technological innovationsc contributed to the rapid growth of population in this period. However, we should also note that the impact of rice culture on population growth was rather limited, for rice culture was not the mainstay of agricultural economy in pre-modern Korea. Indeed we should consider the influence of dry field cropsn population growth. Nevertheless, it is obvious that the proliferation of rice culture was a factor crucial to population growth and regional concentration. (2) How should we characterize the spread of rice culture in the whole period? Evidently rice culture spread from less then 20% of cultivated fields in the fifteenth century to about 36% of them in the early twentieth century. Although rice as a single crop outweighed other crops, rice culture was more then counter-balanced by dry field crops as a whole, due to Korea's unique climate and geography. Thus what we have here in not a typical case of competition between rice culture and day field culture. Besides, the spread of rice culture in the seventeenth and eighteenth centuries accomplished by technological innovations that overcame severe springtime drought, rather than extensive irrigation. Althougt irrigarion facilities did proliferate to some extent, this was achieved by local landlords and peasants rather than the state. This fact contradicts the classical thesis that the productivity of rice culture increased through the state management of irrigation and that this in turn determined the type of society. (3) We should further study other aspects of the transition from the stable population and production struture in the fifteenth and sixteenth centuries to the rapid population growth and excessive density of population thereafter. We should note that there were continuing efforts to reclaim the land in order to solve the severe shortage of land. Changes also took place in the agricultural production relations. The increase in land producrivity developed tenancy based on rent in kind, and this in turn increased the independence of tenants from their landlords. There were changes in family relations-such as the shift to primogeniture as an effort to prevent progressive division of property among multiplying offspring. The rapid population growth also produced a great mass of propertyless farm laborers. These changes had much to do with the disintegration of traditional social institutions and political structure toward the end of the Chos$\breve{o}$n dynasty.

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