• 제목/요약/키워드: multi-cells

검색결과 837건 처리시간 0.027초

대면적 다결정 실리콘 태양전지 제작을 위한 건식식각에 관한 연구 (A study on Dry Etching for Lage Area Multi-Cystalline Silicon Solar Cell)

  • 한규민;유진수;유권종;권준영;최성진;이희덕
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2010년도 하계학술대회 논문집
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    • pp.243-243
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    • 2010
  • This paper two different etching, HF : HNO3 :DI and RIE were used for etching in multi-crystalline Silicon(Mc-Si) solar cell fabrication. The wafers etched in RIE texture showed low reflectance compared to the wafers etched in Acid soultion after SiNx deposition. In light current-voltage results, the cells etched in RIE texture exhibited higher short circuit current and open circuit voltage than those of the cells etched in acid solution. We have obtained 15.1% conversion efficiency in large area($156cm^2$) Multi-Si solar cells etched in RIE texture.

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복수 패턴 인식을 위한 변형된 네오코그니트론 (Modified neocognitron for recognizing multi-patterns)

  • 김태우;최병욱
    • 전자공학회논문지B
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    • 제31B권10호
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    • pp.140-148
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    • 1994
  • 본 논문에서는 입력영상에 존재하는 복수 패턴을 한번의 패스(pass)로 인식할 수 있는 변형된 네오코그니트론을 제안한다. 변형된 네오코그니트론은 특징을 추출하는 S세포층 및 V세포층과 패턴의 크기, 이동, 회전 등 변형에 덜 민감하게 하는 C세포층으로 구성된 계층적 신경망이다. S세포와 V세포들은 DCC(don't care condition)을 적용하여 영상에 존재하는 모든 패턴에 대한 특징을 추출하는 역할을 하며, S세포와 C세포는 추출된 패턴에 대한 위치정보도 함께 가진다. 위치정보는 추출된 특징들이 서로 간섭을 받지 않고 올바른 특징만이 추출되도록 하는 데 이용된다. 제안한 방법은 피드백이 존재하는 선택적 주의 방법과는 달리 단일패스로 인식이 가능하므로 인식시간이 짧으며, DCC와 위치정보를 이용하므로 서로 접촉되어 있는 복수 패턴의 인식도 가능하다.

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광 포획 향상을 위한 다중 아키텍처 식각 기술을 적용한 박막 실리콘 태양전지에 관한 연구 (A Study on Thin-Film Silicon Solar Cells with Multi-Architecture Etching Technique to Improve Light Trapping)

  • 박형기;이준신
    • 한국전기전자재료학회논문지
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    • 제37권3호
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    • pp.337-344
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    • 2024
  • This work focuses on improving the light-harvesting efficiency of thin-film silicon solar cells through innovative multi-architecture surface modifications. To create a regular optical structure, a lithographic process was performed to form it on a glass substrate through various etching processes, from Etch-1 to Etch-3. AZO was deposited on top of the structures and re-etched to create a multi-architectural surface. These surface-modified structures improved the light absorption and overall performance of the solar cell through changes in optical and physical properties, which we will analyze. In addition, we investigated the effect of post-cleaning on the etched glass structures through EDX analysis to understand the mechanism of the etching action. The results of this study are expected to provide important guidelines for the design and fabrication of solar cells and other photovoltaic devices.

Allocation in Multi-way Stratification by Linear Programing

  • NamKung, Pyong;Choi, Jae-Hyuk
    • Communications for Statistical Applications and Methods
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    • 제13권2호
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    • pp.327-341
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    • 2006
  • Winkler (1990, 2001), Sitter and Skinner (1994), Wilson and Sitter (2002) present a method which applies linear programing to designing surveys with multi-way stratification, primarily in situation where the desired sample size is less than or only slightly larger than the total number of stratification cells. A comparison is made with existing methods both by illustrating the sampling schemes generated for specific examples, by evaluating sample mean, variance estimation, and mean squared errors, and by simulating sample mean for all methods. The computations required can, however, increase rapidly as the number of cells in the multi-way classification increase. In this article their approach is applied to multi-way stratification using real data.

Multi-Target Cytotoxic Actions of Flavonoids in Blood Cancer Cells

  • Sak, Katrin;Everaus, Hele
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권12호
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    • pp.4843-4847
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    • 2015
  • To date, cytotoxic effects of flavonoids in various cancer cells are well accepted. However, the intracellular signaling cascades triggered by these natural compounds remain largely unknown and elusive. In this mini-review, the multiplicity of molecular targets of flavonoids in blood cancer cells is discussed by demonstrating the involvement of various signaling pathways in induction of apoptotic responses. Although these data reveal a great potential of flavonoids for the development of novel agents against different types of hematological malignancies, the pleiotropic nature of these compounds in modulation of cellular processes and their interactions certainly need unraveling and further investigation.

미시역학을 고려한 복합재료의 유한요소해석 및 유효 물성치 평가 (Micromechanical Finite Element Analysis and Effective Material Property Evaluation of Composite Materials)

  • 이승표;정재연;하성규
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2003년도 춘계학술발표대회 논문집
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    • pp.220-223
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    • 2003
  • The methodology of micromechanical finite element method (MFEM) is proposed to calculate the micromechanical strains on fiber and matrix under mechanical and thermal loadings. For micromechanical analysis, composite structure is idealized the square and hexagonal unit cells. Boundary conditions are determined to calculate the effective material properties of composites and the strain magnification matrix. And they are verified by comparing with the results from multi cells, and the strain distributions of the unit cells are in accordance with those of the multi cells. Finally, the effective material properties of composite structure are obtained with respect to its fiber volume fraction and compared with results from rules-of-mixture.

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레이저를 이용한 결정질 실리콘 태양전지의 Double Texturing 제조 및 특성 (Characteristics of Double Texturization by Laser and Reactive Ion Etching for Crystalline Silicon Solar Cell)

  • 권준영;한규민;최성진;송희은;유진수;유권종;김남수
    • 한국재료학회지
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    • 제20권12호
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    • pp.649-653
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    • 2010
  • In this paper, double texturization of multi crystalline silicon solar cells was studied with laser and reactive ion etching (RIE). In the case of multi crystalline silicon wafers, chemical etching has problems in producing a uniform surface texture. Thus various etching methods such as laser and dry texturization have been studied for multi crystalline silicon wafers. In this study, laser texturization with an Nd:$YVO_4$ green laser was performed first to get the proper hole spacing and $300{\mu}m$ was found to be the most proper value. Laser texturization on crystalline silicon wafers was followed by damage removal in acid solution and RIE to achieve double texturization. This study showed that double texturization on multi crystalline silicon wafers with laser firing and RIE resulted in lower reflectance, higher quantum yield and better efficiency than that process without RIE. However, RIE formed sharp structures on the silicon wafer surfaces, which resulted in 0.8% decrease of fill factor at solar cell characterization. While chemical etching makes it difficult to obtain a uniform surface texture for multi crystalline silicon solar cells, the process of double texturization with laser and RIE yields a uniform surface structure, diminished reflectance, and improved efficiency. This finding lays the foundation for the study of low-cost, high efficiency multi crystalline silicon solar cells.

Effect of Ultrasound-Induced Hyperthermia on Cellular Uptake of P-gp Substrate and Non-P-gp Substrate in MDR Cells

  • Cho, Cheong-Weon;Kim, Dong-Chool;Shin, Sang-Chul
    • Journal of Pharmaceutical Investigation
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    • 제37권3호
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    • pp.131-135
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    • 2007
  • A previous report recently demonstrated that ultrasound-induced hyperthermia (USHT:0.4 watts (W)/$cm^2$ at $41^{\circ}C$) could increase cellular uptake of P-glycoprotein (P-gp) substrates in P-gp expressing cancer cell lines. Since P-gp plays a major role in limiting drug permeability in the multi-drug resistant (MDR) cells, studies were conducted to elucidate the mechanism of USHT on cellular accumulation of P-gp and non-P-gp substrate in MDR cells. To accomplish this aim, we studied the effects of USHT on the accumulation of P-gp substrate, R123 and non-P-gp substrate, antipyrine in MDR cells. We demonstrated that USHT increased permeability of hydrophobic molecules (R123 and $[^{14}C]$-antipyrine). The enhanced permeability is reversible and size-dependent as USHT produces a much larger effect on cellular accumulation of $[^{14}C]$-antipyrine (MW 188) than that of R123 (MW 380.8). These results suggest that USHT could affect MDR cells more sensitive than BBMECs. Also, the present results point to the potential use of USHT to increase cellular uptake of P-gp recognized substrates, mainly anti-cancer agents into cancer cells.

3차원 동적 다중물리 모델 기반 암세포 증식과정 예측기술 개발 (A STUDY ON CANCER CELL INVASION WITH A THREE-DIMENSIONAL DYNAMIC MULTI-PHYSICS MODEL)

  • 송지환;;김동철
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2010년 춘계학술대회논문집
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    • pp.556-561
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    • 2010
  • This paper proposes a three-dimensional haptotaxis model to simulate the migration of the population of cancer cells. The invasion of the cancer cells relates with the hapto- and the effect of the energy between cells and (ECM). The diffuse interface model is employed, which incorporates haptotaxis mechanism and interface energies. The semi-implicit Fourier spectral scheme is adopted for efficient complications. The simulation results reveal rich dynamics of cancer cells migration.

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다중 셀 MIMO 네트워크를 위한 Hadamard 행렬 Interstream 전송 기반 Blind 채널 추정 (Blind Channel Estimation based on Hadamard Matrix Interstream Transmission for Multi-Cell MIMO Networks)

  • 양재승;모하마드 아부 하니프;박주용;이문호
    • 한국인터넷방송통신학회논문지
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    • 제15권4호
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    • pp.119-125
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    • 2015
  • 본 논문에서는 다중 셀 MIMO (multiple-input and multiple-output) 네트워크를 위한 Hadamard 행렬 인터스트림 (interstream) 전송기반 blind 채널추정을 소개한다. 제안 방법은 다중 셀로 된 이동 단말 네트워크를 기반으로 연구된다. MS (mobile station) 는 양 셀로부터 신호를 받는 것으로 가정한다. 가까운 셀로부터 받은 신호는 원하는 신호로 간주되고, 다른 셀로부터 받은 신호는 간섭신호로 간주된다. 채널은 blind이기 때문에 채널을 추정하기 위해 Hadamard 행렬 패턴의 파일럿 (pilot) 스트림 (stream) 을 전송하면, 대규모 MIMO 채널에 대해 보다 쉽고 빠른 채널 추정이 가능하게 된다. Hadamard 행렬 기반시스템의 계산은 오직 복소 가산 (complex addition) 만 필요하기 때문에, 복소 승산 (complex multiplication) 이 필요한 Fourier 변환을 이용한 방법보다 복잡도가 훨씬 줄어든다. 수치적 분석을 통해 본 결과 제안한 방법이 완벽함을 보여준다.