• Title/Summary/Keyword: Development History

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Development History and Trend of High-Capacitance Multi-layer Ceramic Capacitor in Korea (우리나라 고용량 MLCC 기술 개발의 역사와 전망)

  • Hong, Jeong-Oh;Kim, Sang-Hyuk;Hur, Kang-Heon
    • Journal of the Korean Ceramic Society
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    • v.46 no.2
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    • pp.161-169
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    • 2009
  • MLCC (Multi-layer Ceramic Capacitor) is the most important passive component in electronic devices such as HHP, PC and digital display. The development trend of MLCC is a miniaturization with increasing the capacitance. In this paper, a development history of the high capacitance MLCC in Korea was introduced, and the necessity of the finer $BaTiO_3$ was explained in the viewpoint of the issued electrical and dielectric properties of high capacitance MLCC. The bottleneck technologies to realize the high capacitance was shortly introduced, followed by the prediction of the development trend of MLCC in near future.

Research Trends of Records and Archives Management History in Korea: Retrospect and Prospect (기록관리의 역사에 관한 국내의 연구 동향 - 회고와 전망 -)

  • Kang, Soon-Ae
    • Journal of Korean Society of Archives and Records Management
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    • v.13 no.3
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    • pp.41-65
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    • 2013
  • This study aims at reviewing the research trends of records and archives management history published during the past 12 years, analyzing issues, and suggesting future tasks in related research areas. It starts with categorizing research areas of records and archives management history in archival sciences. All 31 articles have been selected from the 2 journals on archival science and 6 journals on related research areas. In quantitative measurement, the paper draws up 31 kinds of article bibliographies and looks at the current status of subject areas by year and author. In content analysis, selected articles are categorized into 3 subject areas, that is, general history, domestic history, and foreign history. For each subject area, research trends of the historical and regional studies are analyzed. This study concludes with emphasis on a new research direction between practice and points out that academic theory should be required for the future development in records and archives management history.

The Influence of Change in Climatic Environment during the Song-Yuan Dynasty Had on the Development of Medical Science and Disease Emergence (송원(宋元)시대 기후환경변화가 질병과 의학발전에 미친 영향)

  • Kim, Ji-Soo;Jung, Ji-Hun;Park, Hae-Mo
    • The Journal of Korean Medical History
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    • v.31 no.2
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    • pp.53-62
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    • 2018
  • It is known that the development of medical science is influenced by various social environmental factors. Historically, Chinese Medicine developed the most during the Song Yuan dynasty, and the reason for this was known to be due to socio-political factors. According to recent studies, however, this period also had severe changes in climate and environment. Therefore, this study was conducted under the premise that this change in climate and environment influenced medical development. When looking at the coldness of the 11th~12th century and data indicating warming before and after this period, the Song Yuan dynasty went through drastic periods of climate change. Therefore, diseases related to heat such as bubonic plague, measles, and malaria were common. Furthermore, due to occasional wars during the Song Yuan dynasty, social unrest was aggravated and infectious diseases spread due to land development and environmental pollution. As the health of people were threatened due to these factors, the printing and distribution of medical text were encouraged, and during this process, the great 4 doctors of Jin-Yuan appeared. The reason why they studied cures for infectious diseases due to heat was related to climatic environment change. The development in medical science is closely related to socio-political factors, however the change in climatic environments are inevitably related to disease emergence as well. Therefore, it should always be taken into consideration as an important factor that promotes development in medical science.

Development of the concept of complex number and it's educational implications (복소수 개념의 발달과 교육적 함의)

  • Lee, Dong-Hwan
    • Journal for History of Mathematics
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    • v.25 no.3
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    • pp.53-75
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    • 2012
  • When imaginary numbers were first encountered in the 16th century, mathematicians were able to calculate the imaginary numbers the same as they are today. However, it required 200 years to mathematically acknowledge the existence of imaginary numbers. The new mathematical situation that arose with a development in mathematics required a harmony of real numbers and imaginary numbers. As a result, the concept of complex number became clear. A history behind the development of complex numbers involved a process of determining a comprehensive perspective that ties real numbers and imaginary numbers in a single category, complex numbers. This came after a resolution of conflict between real numbers and imaginary numbers. This study identified the new perspective and way of mathematical thinking emerging from resolving the conflicts. Also educational implications of the analysis were discussed.

Development of Eggs and Early Life History of Korean Bitterling, Rhodeus pseudosericeus (Acheilognathinae) (한강납줄개, Rhodeus pseudosericeus (Acheilognathinae)의 난 발생과 초기생활사)

  • Kim, Chi-Hong;Kang, Eon-Jong;Kim, Jong-Hwa
    • Korean Journal of Ichthyology
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    • v.18 no.3
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    • pp.266-272
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    • 2006
  • The egg development and early life history of Korean endemic bitterling Rhodeus pseudosericeus were observed under the controlled water temperature, $17.0{\pm}0.5^{\circ}C$. Fertilized eggs are opaque yellow in color, measuring 2.9~3.1 mm in length and 1.6~1.9 mm in breadth. The eggs of this species began to hatch about seventy hours after insemination and the range of total length of larvae were 3.2~3.4 mm. The larvae reached at the heterotrophic stage about twenty-five days after hatching. R. pseudosericeus had a pair of wing-shaped yolk projection during the prelarval stage that is a common character of the genus Rhodeus.

The History, Present and Convergent Development Plan in Sport-Climbing (스포츠클라이밍의 역사, 현황 및 융합적 발전 방안)

  • Han, Gun-Soo;Park, Jae-Ahm
    • Journal of the Korea Convergence Society
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    • v.12 no.4
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    • pp.179-190
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    • 2021
  • This study tried to provide the way of development in sport-climbing base on the history and present of Korean sport climbing. In terms of the policy, single sport climbing association needs to be formed and separated from Korean Alpine Federation. School teams and athletes are required to expand, college teams in particular. These athletes could be sport instructors and professional athletes vitalizing competition and sport climbing after graduation. Public sport climbing facilities need to be counted accurately. Ministry of Culture, Sports and Tourism needs to administrate the public sport blimbing facilities by counting and checking the facilities with the responsibility.

History of Radiation Therapy Technology

  • Huh, Hyun Do;Kim, Seonghoon
    • Progress in Medical Physics
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    • v.31 no.3
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    • pp.124-134
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    • 2020
  • Here we review the evolutionary history of radiation therapy technology through the festschrift of articles in celebration of the 30th anniversary of Korean Society of Medical Physics (KSMP). Radiation therapy technology used in clinical practice has evolved over a long period of time. Various areas of science, such as medical physics, mechanical engineering, and computer engineering, have contributed to the continual development of new devices and techniques. The scope of this review was restricted to two areas; i.e., output energy production and functional development, because it is not possible to include all development processes of this technology due to space limitations. The former includes the technological transition process from the initial technique applied to the first model to the latest technique currently used in a variety of machines. The latter has had a direct effect on treatment outcomes and safety, which changed the paradigm of radiation therapy, leading to new guidelines on dose prescriptions, innovation of dose verification tools, new measurement methods and calculation systems for radiation doses, changes in the criteria for errors, and medical law changes in all countries. Various complex developments are covered in this review. To the best of our knowledge, there have been few reviews on this topic and we consider it very meaningful to provide a review in the festschrift in celebration of the 30th anniversary of the KSMP.

The Development Progress of Korean Aviation Industry and its Investment Strategy Based on the Evidence and the 4th Industrial Revolution

  • Kim, Jongbum
    • International Journal of Aerospace System Engineering
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    • v.5 no.2
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    • pp.1-7
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    • 2018
  • This study examines the history of Korean aviation industry and presents the investment strategy based on the evidence and the 4th industrial revolution. Looking at the evolution of the Korean aviation industry and its technological development will be a great help to support industrial and technological innovation in the future. The modern aviation industry is divided into stages of development, focusing on maintenance of equipment introduced in advanced countries, localization through license assembly, production of products based on technology, and international joint development. The development of aeronautics technology has been progressing towards a general improvement of economic efficiency, aircraft safety efficiency through environmental-friendliness, unmanned operation, and downsizing. The Korea Aerospace Research Institute has secured key technologies through development of several aircrafts such as Experimental Aircraft Kachi, EXPO Unmanned Airship, Twin-engine Composite Aircraft, Canard Aircraft, Multi-Purpose Stratosphere unmanned-airship, Medium Aerostats, Smart UAV, Surion, EAV-2H, KC-100, and OPV. The development strategy is discussed at the level of the evidence-based investment strategy that is currently being discussed, and so the investment priorities in aircraft is high. Current drone usage and development direction are not only producing parts using 3D printer, but also autonomous flight, communication (IoT, 5G), information processing (big data, machine learning). Therefore, the aviation industry is expected to lead the fourth industrial revolution.

Effects of Climate and Human Aquatic Activity on Early Life-history Traits in Fish (기후변화와 수상레저활동 인구변화가 어류의 초기생활사에 미치는 영향)

  • Lee, Who-Seung
    • Korean Journal of Ecology and Environment
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    • v.46 no.3
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    • pp.395-408
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    • 2013
  • Environmental condition can induce changes in early life-history traits in order to maximise the ecological fitness. Here I investigated how temperature change and variation in human aquatic activity/behaviour affect early life-history consequences in fish using a dynamic-state-dependent model. In this study, I developed a general fish's life-history model including three life-history states depend-ing on foraging activity, such as body mass, mass of reproductive tissue (i.e., gonadal development) and accumulated stress (i.e., cellular or physiological damage). I assumed the level of foraging activity maximises reproductive success-ultimately, fitness. The model predicts that growth rate, development of reproductive tissues and damage accumulation are greater in higher temperature whereas higher human aquatic activity rapidly reduced the growth rate and development of reproductive tissue and increased damage accumulation. While higher foraging activity in higher temperature is less affected by human aquatic activity, the foraging activity in lower temperature rapidly declined with human aquatic activity. Moreover, lower survival rate in higher temperature or human aquatic activity was independent on mortality rate due to human aquatic activity or mortality rate when foraging activity, respectively. However, the survival rate in lower temperature or human aquatic activity was dependent on these mortality rates. My findings suggest that including of early life-history traits in relation to climate-change and human aquatic activity on the analysis may improve conservation plan and health assessment in aquatic ecosystem.

Shmuel N. Eisenstadt and the Comparative Political History of Pre-Eighteenth-Century Empires

  • De WEERDT, Hilde
    • Asian review of World Histories
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    • v.4 no.1
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    • pp.133-163
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    • 2016
  • This essay critically analyses the legacy of Eisenstadt's The Political Systems of Empires for the comparative political history of pre-industrial empires. It argues that Eisenstadt has given us a rich toolkit to conceptualize the formation, maintenance, and dissolution of empires by theorizing the structural relationships between social groups in large-scale polities and among such polities, and by analysing global patterns of development in the distribution of the sources of social power. The Political Systems of Empires provides an inventory of key questions and dynamics that a comparative history of power relationships in empires cannot ignore. This essay, furthermore, discusses three methodological problems in Eisenstadt's work which have had a significant impact on comparative empire studies between the 1980s and the 2000s. The essay argues that certain shared features of comparative studies of pre-industrial empires help perpetuate Eurocentric analyses: the foregrounding of select empires and periods as ideal types (typicality), the focus on macro-historical structures and dynamics without the integration of social relationships and actions in historical conjunctures (the lack of scalability), and the search for convergence and divergence. These features need to be overcome to make Eisenstadt's legacy viable for comparative political history.