• Title/Summary/Keyword: SI이론

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A study on the theory of "zhong-hua" in the Sung dynasty (송대 "중화(中和)" 사상에 관한 일고찰 - 사마광(司馬光)과 한유(韓維)의 서신 교환을 중심으로 -)

  • Lim, Myunghee
    • The Journal of Korean Philosophical History
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    • no.38
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    • pp.251-273
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    • 2013
  • This paper deals with mind and human nature dispute between Si-Ma guang and Han-Yu in the Northern Sung Dynasty, focused upon the "zhong-hua". The letter exchange between Si-Ma guang and Han-yu, which were the mind and human nature debate between a representative intellectually of the Confucianism and a scholar who absorbed in the Buddhism, can provide the discussion on various ideological origins that affected the development of the mind and human nature theory. Moreover, the contents of a letter from both of them can be used as an important cue to observe the discussion under what ideological foundations the mind and human nature theory could be embodied in the future and what advance it has made and what is its philosophical meaning.

Does City Function Depend on City Size? (도시의 기능은 규모에 의존하는가? - 네트워크 도시이론의 적용가능성을 중심으로 -)

  • Nam, Kichan;Kim, Brian Hong-Sok
    • Journal of the Korean Regional Science Association
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    • v.31 no.1
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    • pp.3-20
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    • 2015
  • The objective of this study is to identify the applicability of urban network theory. The degree of network and city size of 163 Si-Guns in Korea are used to perform an empirical analysis for 2005 and 2010. The result indicates that the effect of city size (based on central place theory) is still larger than the network effect (based on urban network theory). However, the effects are different according to the industrial types. The size-based effectis more efficient in manufacturing sector, whereas the network-based effect is more efficient in service industry. The trend from 2005 to 2010 indicates that there is an increasing pattern in network-based effect and decreasing patternin size-based effect. It is necessary to recognize continual benefit of the sized-based effect, however it is also important to distinguish different characteristics of the functional form by the size and network. The feasibility of the urban network theory is tested in this study with the empirical analysis and recommends the importance of policy implication with recognition of the distinction between size and network-based effects.

A study of internal reflectance enhancement for crystalline silicon solar cell adopted with Bragg mirror structure using TCAD simulation

  • Jeong, Sujeong;Kim, Soo Min;Lee, Kyung Dong;Kim, Jae eun;Park, Hyomin;Kang, Yoonmook;Lee, Hae-seok;Kim, Donghwan
    • Proceedings of the Korean Vacuum Society Conference
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    • 2016.02a
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    • pp.421.2-421.2
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    • 2016
  • 고효율 태양전지에서 후면 반사 방지막은 장파장대(900nm~1200nm) 빛의 내부 반사를 증가시켜 광흡수도를 개선한다. 태양전지 후면에 박형 절연층 구조를 구성함으로써 특정 파장에서 높은 반사도를 얻을 수 있는 Bragg mirror 구조를 이론적으로 계산할 수 있다. Bragg mirror 구조를 이용하여 태양전지의 후면 반사층(Rear reflector layer)을 형성함으로써 태양전지 내부의 광흡수도를 개선할 수 있다. 후면 반사 방지막(Rear anti-reflection coating)으로 사용되는 Al2O3와 SiOxNy 또는 이러한 두 가지 물질의 겹층 구조를 구성하여 장파장대 빛의 반사도 차이에 의한 광흡수도 개선 정도를 광학 시뮬레이션을 통해 계산하였다. 광학 시뮬레이션은 TCAD를 이용하였으며 두 가지 겹층 구조에서 각 반사 방지막의 두께에 따른 단락 전류(Jsc)의 개선 정도, 후면 반사층 두께의 최적화 조건을 계산하였다. 후면 반사방지막을 제외한 기본적인 태양전지 구조는 n-type PERC 구조를 사용하였으며, 후면 반사방지막만의 광학적 특성을 살펴보기 위해 전극은 광학적으로 투명하다고 가정하였다. 반사방지막 두께의 범위는 Al2O3(5-30nm), SiNx(150-300nm), SiOxNy(150-300nm)에서 수행하였으며, 각각 1nm, 2nm 간격으로 진행하였다. Al2O3/SiOxNy 구조에서는 단락 전류가 32.45-32.87mA/cm2 값을 가진다. Al2O3/SiNx 구조에서는 단락 전류가 32.59-32.87mA/cm2 값을 가진다. 결론적으로, 후면 반사방지막의 겹층 구조를 통해 광흡수도를 증가 시킬 수 있으며, TCAD 시뮬레이션을 통하여 입사되는 태양광 스펙트럼에 최적화된 구조를 설계할 수 있다.

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FABRICATIO0N OF NASICON ELECTROLYTES

  • Choi, Soon-Don;Park, Jung-Woo
    • Journal of Sensor Science and Technology
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    • v.4 no.1
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    • pp.35-42
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    • 1995
  • Conventional ball-milling technique was used to synthesize NASICON powders. The NASICON powders were made from three kinds of component powders : coarse($ZrO_{2}$, $Na_{3}PO_{4}$, $SiO_{2}$), fine ($ZrO_{2}$, $Na_{3}PO_{4}$, $SiO_{2}$) and fine ($ZrSiO_{4}$, $Na_{3}PO_{4}$) powders. The fine component powders were easily reacted to form the desired product at $1100^{\circ}C$ or higher, whereas incomplete reaction due to the coarse component powders occurred even at $1170^{\circ}C$. The finer the grain size of the starting powders was, the higher the bulk density of NASICON electrolyte after sintering was observed. Almost single phase NASICON electrolytes with more than 95% of the theoretical density, $3.27g/cm^{3}$, could be fabricated by sintering for $40{\sim}60$ hours at temperatures between 1150 and $1170^{\circ}C$.

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Data Measurement for the Volumetric Efficiency of SI Engines (가솔린 엔진의 흡기효율 데이터 측정)

  • Jang, Hyun-Tak
    • Proceedings of the KAIS Fall Conference
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    • 2010.05b
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    • pp.1163-1165
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    • 2010
  • 가솔린 기관의 체적 효율은 흡기 장치의 효율의 척도로 표현된다. 현재 체적효율은 4행정 가솔린 엔진의 흡기장치의 특성과 공연비 제어를 위한 중요한 파라미터로 사용되고 있다. 체적 효율은 이론적으로 실린더로 흡입 가능한 양에 대한 실제로 실린더로 흡인한 공기량의 비율이다. 체적효율은 엔진회전 속도와 흡기다기관 부압에 따라 결정되는 종속변수이다. 체적 효율은 정상상태와 과도상태와 같은 엔진의 모든 운전조건을 시험하는데 한계와 제약이 매우 크다. 이 논문에서는 선형 알고리즘을 사용하여 체적 효율의 파라미터를 규명하여 선형 다항식 모델을 개발한다. 그리고 실험으로 구한 체적효율 데이터와 다항식 모델을 비교하고 객관적인 타당성을 평가 하였다.

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Theoretical analysis of grainboundary recombination velocity in polycrystalline Si solar cell (다결정규소(多結晶硅素) 태양전지(太陽電池)의 입계면(粒界面) 재결합(再結合) 속도(速度)에 관(關)한 이론적(理論的) 분석(分析))

  • Choi, B.H.;Bark, I.J.;Chea, Y.H.
    • Solar Energy
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    • v.5 no.2
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    • pp.54-59
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    • 1985
  • Due to the grainboundary recombination and the poor diffusion length, the polycrystalline cell efficiency is lower than the singlecrystalline cell. In order to define the effect of grains and grain-boundaries, 2 - dimensional differential diffusion equations of minority carrier are modelled. To solve them, two theoretical formulas are derived, which can be evaluated the grainboundary recombination velocity and the grain diffusion length. Also computer-aided numerical analysis is given.

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가시광 무선 통신 기반의 응용 서비스 모델 개발 동향

  • Hwang, Jun-Ho;Ryu, Di-Si;Yu, Myeong-Sik
    • Information and Communications Magazine
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    • v.30 no.1
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    • pp.77-83
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    • 2012
  • 가시광 무선 통신 기술은 발광소자인 LED와 수광 소자를 이용한 차세대 무선 통신 기술로서 많은 관심을 받고 있다. 더욱이 최근들어 연구 초장기의 이론적 연구를 벗어나 실제 상용 모델에 대한 개발 및 구현 결과가 발표되고 있다. 이에 본 보고에서는 가시광 무선 통신 기반의 실내외 응용 서비스 모델 개발을 위한 최근의 연구 개발 동향을 소개한다.

Study on the Relationship Among Children's Theory of Mind, Social Competence, and Emotional Intelligence (유아의 마음이론, 사회적 능력, 그리고 정서 지능 간의 관련성 연구)

  • Ahn, Hyo Jin;Kim, Sang Lim;Lee, Si Ja
    • Korean Journal of Childcare and Education
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    • v.8 no.5
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    • pp.179-202
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    • 2012
  • This study examined the relationship among children's theory of mind, social skills, and emotional intelligence. A total of 76 five-year old children in the Seoul area participated in this study. Children were tested on three different type of theory of mind tasks and teachers rated their children's emotional intelligence and social competency. SPSS 18, t-test, correlation analysis, and step-wise of multilateral regression were performed for data collection. The results were as follows: First, 40.8% of participants passed the task of theory of mind. There were significant differences in total score of theory of mind, social competence skills, and emotional intelligence between successors and failures. Second, by gender, there were significant differences in total score of theory of mind, social competence skills, and emotional intelligence. Third, there was a relationship between theory of mind and social competence skills, social competence skills and emotional intelligence, and theory of mind and emotional intelligence.

Measurements of X-Ray Production Cross-Sections for 0.5¡­1.2-MeV Proton Beam (0.5~l.2-MeV 양성자빔에 대한 X-선 발생단면적의 측정)

  • Hae-ill BAK;Jun-Gyo BAK
    • Nuclear Engineering and Technology
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    • v.22 no.2
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    • pp.108-115
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    • 1990
  • The measurements of X-ray production cross-sections for 0.5~1.2-MeV proton beam are carried out on Cu and Au. For this experiment, the proton tram generated from the SNU 1.5-MV Tandem Van do Graaff accelerator is Incident on the target. The X-rays and the backscattered protons from the irradiated target are detected simultaneously by the Si(Li) X-ray detector and the SSB (Silicone Surface Barrier) charged particle detector The measured values of X-ray production cross-sections are compared with other experimental values and theoretical values such as the PWBA (Plane Wave Born Approximation) and the ECPSSR(Perturbed Stationary State corrected Energy loss, Coulomb deflection, Relativistic effects) values. For measured cross-sections near 1.0- MeV proton energy, the ECPSSR (D.D. Cohenet al., 1985) shows better agreement than the PWBA. Particularly, that of Au for 1.2 MeV proton beam is 9.69$\pm$ 0.39 barns which deviates from the ECPSSR by less than 5%. and the experimental data for 0.5~1.2- MeV proton agree with most of other experimental values within 30%.

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What Factors Make the Delay of the Information System Project Implementation? (무엇이 정보시스템 프로젝트 일정을 지연시키는가?)

  • Seoung, Byung Ook;Park, Sang Cheol;Koh, Joon
    • Knowledge Management Research
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    • v.22 no.1
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    • pp.1-19
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    • 2021
  • Large-scaled hospital information system projects are often delayed than originally planned. Regarding project management, it is necessary to examine main factors triggering the schedule delay and to analyze the causality of such delay. This study tries to find the delay factors and causal relationship between them based on the case of the hospital information system development project by using the grounded theory method. It turned out that 'unrealistic scheduling' affects overall schedule delays like domino phenomenon, and 'poor analysis of existing systems' leads to poor quality of work analysis while 'poor subsystem integrated interface' triggers poor design quality. This study found out the factors affecting the delay of a project, analyzing cause-and-effect relationships between them in the academic side. From the practical view, it shows a solution to minimize delays in the project schedule for each of SI companies, hospitals and project managers.