http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : 유충현 (검색결과 135 건)
- 무료
- 기관 내 무료
- 유료
-
유충현,오주미 한국수학사학회 2024 Journal for history of mathematics Vol.37 No.2
본 논문에서는 선형대수학을 이루는 주요 개념인 행렬, 벡터, 일차변환이 어떻게 발생하고 연결되어가며 하나의 영역으로 통합되어 가는지에 대한 역사 발생적 과정을 살펴본다. 이 과정에서 대수적 ·기하학적 관점에 대한 선형성이 어떻게 인식되고 통합되어 가는지에 대해 논의하고자 한다. 나아가 이와 같은 역사 발생적 과정을 바탕으로 학교 수학에서 통합적 개념으로서의 선형대수의 역할에 대해 고찰하고자 한다. In this article, we study the historical development of how the main concepts of linear algebra - matrices, vectors, and transformations - arise, are connected then integrated into a category. Also we study how linearity is recognized and integrated into algebraic and geometric viewpoint. Furthermore, we discuss, based on this, the role of linear algebra as a unifying concept in a school mathematics.
-
-
대기압 MOCVD 시스템을 이용하여 Si 기판 위에 자발적으로 형성된 InAs 양자점에 대한 연구
유충현,Yoo, Choong-Hyun 한국전기전자재료학회 2005 전기전자재료학회논문지 Vol.18 No.6
Fully coherent self-assembled InAs quantum dots(QDs) grown on Si (100) substrates by atmospheric pressure metalorganic chemical vapor deposition(APMOCVD) were grown and the effect of growth conditions such as growth rate and growth time on quantum dots' morphology such as densities and sizes was investigated. InAs QDs of 30 - 80 nm in diameters with densities in the range of (0.6 - 1.7) x $10^{10}\;cm^{-2}$ were achieved on Si substrates and InAs layer was changed from 2 dimensional growth to 3 dimensional one at a nominal thickness less than 0.48 ML. This is attributed to the higher ambient pressure of APMOCVD suppressing of In segregation from the 2 dimensional InAs layer. This In segregation looked to disturb the dot formation especially when the growth rate was low so that the dots became less dense and bigger as the growth rate was lower.
-
GaAs 기판 위에 EDMIn과 TBP로부터 성장되고 양극산화 처리된 InP Schottky Diode
유충현 한국전기전자재료학회 2003 전기전자재료학회논문지 Vol.16 No.6
Au/oxide/n-InP Schottky diodes were fabricated from heteroepitaxial InP layers grown on GaAs substrates by the metalorganic vapor phase epitaxy (MOVPE) method from a new combination of source materials: ethyldimethylindium (EDMIn) and tertiarybutylphosphine (TBP). Anodic oxidation technique by using a solution of 10 g of ammonium pentaborate in 100 cc of ethylene glycole as the electrolyte was used to deposit a thin oxide layer. The barrier heights determined from three different techniques, current-voltage (I-V) measurements at room temperature and in the temperature range of 273 K - 373 K, and room temperature capacitance-voltage (C-V) measurements are in good agreement, 0.7 - 0.9 eV which is considerably high as compared to the 0.45 - 0.55 eV in Au/n-InP Schottky diode without a Passivation layer. The ideality factors of 1.1 - 1.3 of the Schottky diodes were also determined from the I-Y characteristics. Deep level transient spectroscopy (DLTS) studies revealed only one shallow electron state at 92.6 meV below the bottom of the conduction band and no deep state in the heteroepitaxial InP layers grown from EDMIn and TBP.
-
-
유충현 청주대학교 2009 産業科學硏究 Vol.26 No.2
Effect of high-temperature annealing on structural and optical characteristics of fully coherent self-assembled InGaAs quantum dots grown on GaAs substrates grown at 500 ℃ by atmospheric pressure metalorganic chemical vapor deposition(APMOCVD) was investigated. There was no appreciable change in structural and optical characteristics of dots when a rapid cooling at room temperature for 10 min. was performed between the growth and high-temperature annealing while quantum dots were almost diminished when annealed without a rapid cooling step after the growth, which may indicate that a rapid cooling is a key factor to maintain the structural and optical characteristics of dots. And photoluminescence measurements revealed that annealing temperature was found more critical to the structural and optical characteristics of dots than annealing time, which may indicate that the morphological and optical change due to thermal annealing is done instantly when the dots are exposed to high temperature annealing.
-
朝鮮 算學의 피타고라스 정리, 句股術의 분석을 통한 朝鮮 算學의 性格과 수학교육적 가치에 대한 연구
유충현 동아대학교 석당학술원 2011 石堂論叢 Vol.0 No.51
In view of the status of Korea in the World, Korea traditional mathematics is not introduced properly to the world. It is neglect that interest and research in Korea traditional mathematics not be enough dealt with. Chosun mathematics in the history of Korea traditional mathematics is the largest share. Chosun mathematics was not dependent on Chinese mathematics, rather than it has been developed by itself. Chosun mathematics was also sometimes higher rather than the level of Chinese mathematics. China has even surpassed the math. One of the most important areas in Chosun mathematics, Gou Gu Shu was not in a matter of simple right triangle, rather than it was the most important an instrumental concept to study the nature of the mathematics in the algebra and geometry. This paper explore value of mathematics education and the nature of Chosun mathematics through the analysis of Gou Gu Shu, Pythagorean Theorem of Chosun mathematics. 세계 속의 한국의 위상에 비추어 본다면 한국 전통수학이 세계에 제대로 소개되지 않고 있음은 안타까운 일이 아닐 수 없다. 한국 전통수학에 대한 관심과 연구는 소홀이 다루어질 수 없는 일이다. 한국 전통수학의 역사에 있어서 朝鮮 算學이 가장 많은 비중을 차지하고 있다. 朝鮮 算學은 중국 算學을 그대로 답습하기보다는 자체적인 연구를 통하여 朝鮮 算學 자체의 발전을 이룩하기도 하였으며 때로는 朝鮮 算學의 수준이 중국 算學을 능가하기도 하였다. 朝鮮 算學에서 가장 주요한 분야 중의 하나인 句股術은 단순한 직각 삼각형의 문제에서 벗어나 代數學에서 가장 중요한 방정식 이론과 도형의 성질을 연구하는 데 가장 많이 사용되는 도구적 개념으로서 算學 전반의 발전과 함께 발전하였다. 본 논문은 朝鮮 算學의 피타고라스 정리인 句股術을 분석하고 이를 바탕으로 朝鮮 算學의 性格과 그 수학교육적 가치를 탐색한다.
-
TiW/Au/TiW 구조 내 Au 박막의 노이즈 특성에 관한 연구
유충현 청주대학교 2011 産業科學硏究 Vol.28 No.2
The noise properties of gold films and the applicability of the noise measurement technique to determine the parameters associated with the electromigration process of gold films have been studied. Excess noise of gold films was investigated at various temperatures. These films were found to have excess noise spectral densities which were frequency dependent between 1 and 40 Hz and may be represented by k/fα with . These films also presented temperature dependency of the normalized magnitude of excess noise. However, unlike aluminum films, no temperature at which the normalized magnitude showed any noticeable peak was detected. Because of lack of a peak, it was not possible to determine the activation energy of gold via noise measurements.
-
AlGaAs로 둘러싸인 InGaAs 양자점의 열적 안정성
유충현 청주대학교 2013 産業科學硏究 Vol.31 No.1
Thermal stability of InGaAs quantum dots embedded in an AlGaAs layer was investigated. AlxGa1-xAs embedding layer was found to be helpful to the thermal stability of quantum dots and it was most enhanced when the Al composition in AlGaAs was 0.5. However AlGaAs embedding layer was found to be not good enough, because that had to be grown at high temperature after the growth of InGaAs quantum dots and their structural and optical characteristics were deteriorated instantly when they were exposed to high temperature.
-
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
