• Title/Summary/Keyword: 형성조건

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실리콘 태양전지의 후면 점접촉 구조를 위한 Al 확산에 의한 국부 후면전계의 제조

  • Lee, Jun-Seong;Gwon, Sun-U;Song, Cheong-Ho;Park, Seong-Eun;Park, Ha-Yeong;Song, Ju-Yong;Park, Hyo-Min;Yun, Se-Wang;Kim, Dong-Hwan
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2009.05a
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    • pp.54.2-54.2
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    • 2009
  • 결정질 실리콘 태양전지의 알루미늄 후면전극이 패시베이션층의 공극을 통하여 확산됨으로써 국부 후면전계(local back surface field)가 형성되는 후면 점접촉 구조를 제조하였으며, 이에 대한 공정조건 및 특성을 연구하였다. 후면 패시베이션층은 실리콘 기판과 금속전극사이에 삽입됨으로써 표면 재결합속도를 낮추고, 후면 반사도를 높여 광흡수 경로를 증가시킬 수 있다. 고가의 사진식각기술 대신에 저가의 단순한 공정인 레이저 식각기술을 사용하여 후면 패시베이션층에 균일하고 잘 정렬된 공극 패턴을 형성할 수 있었다. 레이저 식각 조건 및 소성조건에 따른 Al 확산 국부 후면전계의 단면 형상을 주사전자현미경(SEM)을 사용하여 관찰하였으며 이에 대한 전기적, 광학적 특성 변화를 조사하였다.

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Interspecific Variation in the Protoplast Formation of the Genus Cellulomonas (Cellulomonas속 종간의 원형질체 형성조건의 차이에 대하여)

  • Lee, Eun-Ju;Bae, Moo
    • Korean Journal of Microbiology
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    • v.24 no.2
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    • pp.154-160
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    • 1986
  • In order to develope interspecific fusion of the genus Cellulomonas capable of assimilation cellulose, the optimun conditions for the protoplast formation was investigated to examine the susceptibility of cell wall, between different species of the same genus using scanning electron microscope. The variation in the susceptibilities of Cellulomonas sp. CS 1-1 and C. flavigena to lysozyme treatment were considerably remarkable, although they belong to the same genus. The rate of protoplast formation of CS1-1 was 99.9% being treated with lysozyme $(100{\mu}g/ml)$ for 30 minute and that of C. flavigena was about 80% being treated at the concentration of $600{\mu}g/ml$ of lysozyme for 6 hours. The susceptibility of cell wall to the lysozyme treatment on protoplast formation of the strain, CS1-1 seems not to be depend on the cultural periods of cells. On the contrary, that of C. flavigena was considerably depend on the periods. Cells of C. flavigena at mid exponential phase could be more efficiently converted to protoplast cells than those at late exponential phase be done. The rate of the protoplast formation was 95%, when cells of C. flavigena at mid exponential phase were treated with lysozyme $600{\mu}g/ml$ for 6 hours and observed by SEM. In the evalution of protoplast formation of the CS1-1 results of counting method in plate after osmotic shock treatment were similar to the results of the direct observation method by means of SEM. But in the case of C. flavigena the latter method was much more reliable than the former, because the differences between the number of spheroplasts and protoplasts were not able to figure out on conuting the number of protoplast after osmotic shock tretment.

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CGI 클러스터 형성조건과 효율적 구축방안(광주지역을 중심으로)

  • 한창완
    • Korea Information Processing Society Review
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    • v.11 no.1
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    • pp.62-70
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    • 2004
  • 디지털콘텐츠산업은 70년대와 80년대의 하드웨어 중심의 산업 시대와 90년대의 네트워크 중심의 시대를 거치면서, 21세기에 이르러 핵심 산업으로 급부상하였고, 급속도로 발전한 첨단의 하드웨어와 네트워크에 고부가가치를 창출할 수 있는 실제적인 동력으로 자리매김하고 있다.(중략)

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Assessment of Long-Term Performance of Geotextiles by Field Test (현장시험에 의한 지오텍스타일의 장기성능 평가)

  • 전한용;안양님;유중조;류원석
    • Proceedings of the Korean Fiber Society Conference
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    • 2003.04a
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    • pp.366-367
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    • 2003
  • 토목합성재료의 내후성은 사용되는 원료 물질, 기후조건, 하중조건, 노출 기간 등에 따라 상이한 결과를 나타내며, 이러한 영향인자에 대한 많은 연구가 국내외적으로 이루어졌으나 이는 각 적용지역의 환경조건을 고려하여 실시된 경우로 지역적인 조건과 기후 차이로 국내 여건에 적합한 데이터라 할 수 없다. 본 연구에서는 임시구조물로 적용된 분리형 보강토 옹벽의 전면체를 형성하는 부직포 지오텍 스타일에 대해 현장 적용 노출시험을 실시하였으며 약 1년 간의 지속적인 계측을 통해 실제 국내 현장에서 나타나는 부직포 지오텍스타일의 내후성 거동에 대해서 평가하였다. (중략)

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Modeling of Combustion and Pollutant Emissions in IC Engines (내연기관 연소 및 pollutant 모델링)

  • Huh Kang Y.
    • Journal of the Korean Society of Visualization
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    • v.3 no.2
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    • pp.14-20
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    • 2005
  • 내연기관 연소는 난류유동, 분무, 연소, 열전달의 복합적인 현상으로서 열역학적 해석이 주류를 이루어 왔으나 컴퓨터의 발전에 따라 효율 개선과 공해 저감을 목표로 전산유체해석 기법이 적극적으로 도입되고 있다. 내연 기관 연소의 근간을 형성하는 난류 연소 모델링의 기본 개념으로서 가솔린엔진에서의 예혼합연소와 디젤엔진에서의 확산연소에 대한 영역조건평균(zone conditional averaging) 모델과 조건평균닫힘(conditional moment closure) 모델에 대해 설명하였으며 $NO_x$와 soot 예측에 대한 적용과 엔진응용 사례를 소개하였다.

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Effects of Acylase Treatment Episodes on Multispecies Biofilm Development (Acylase의 처리 시기 및 기간이 다종 생물막 형성에 미치는 영향)

  • Ji Won, Lee;So-Yeon, Jeong;Tae Gwan, Kim
    • Microbiology and Biotechnology Letters
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    • v.50 no.4
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    • pp.548-556
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    • 2022
  • Acylases can have a significant effect on biofilm formation owing to their quorum quenching activity. In this study, we investigated the effects of acylase treatment episodes on multispecies biofilm development. A consortium composed of 9 species belonging to different genera was allowed to form biofilms for 5 days under various treatment episodes (different treatment periods, 1, 2, 3, or 4 days; and two application timings, beginning or later) at 1, 5, 10, 20 and 50 mg·l-1 acylase concentrations. The acylase treatment for 5 days showed that acylase concentration was negative with biofilm development (linear regression, Y = -0.05·x + 2.37, p < 0.05, R2 = 0.88). Acylase was more effective in reducing biofilm formation when it was applied in the beginning (vs. in later development stage) at all acylase concentrations (p < 0.05). ANOVA indicated that treatment period was significant on biofilm formation in both application timings at ≥ 10 mg·l-1 (p < 0.05). Linearity test results showed that all slope values between period and biofilm were negative in both timings at ≥ 10 mg·l-1 (p < 0.05, except for the later application at 20 mg·l-1). When temporal biofilm dynamics were monitored at 20 mg·l-1, biofilms gradually increased with time at all treatment episodes (p < 0.05), and slope values in linear regression between biofilm and time were lower when acylase was applied in the beginning (p < 0.05). Our findings suggest the importance of the acylase treatment period and application timing on biofilm control.

Ettringite/Thaumasite Formation, Stability and Their Effect on Deterioration of Concrete (에트린자이트/사우마사이트의 형성 및 안정도와 콘크리트 성능저하에 미치는 영향)

  • 이효민;황진연
    • Journal of the Mineralogical Society of Korea
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    • v.16 no.1
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    • pp.75-90
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    • 2003
  • Ettringite and thaumasite were observed in some concrete. The morphology and occurrence of these minerals were closely examined by performing SEM/EDAX analyses. We also experimentally induced the concrete deterioration using $Na_2SO_4$ solution with application of various environmental conditions. The stability of these minerals and deterioration characteristics under applied experimental conditions were determined. Abundant ettringite formed by“through solution reaction”occurred in many open spaces, and some microscopic ettringite formed by "tophochemical replacement" of calcium aluminate also occurred in cement paste. Severe cracking of cement paste causing premature deterioration was often associated with ettringite location. Under specific condition, ettringite was transformed to thaumasite, tricthloroaluminate, or decomposed. Thaumasite occurred with association of ettrinsite in concrete containing carbonate aggregate being subject to dedolomitization or in some concrete being subject to carbonation. Thaumasite appears to be formed under the similar condition to the general ettringite forming condition, but it formed solid solution with ettringite by substituting pre-existing ettringite. Ettringite can also be transformed to trichloroaluminate in the presence of abundant chlorides, but trichloroaluminate changed back to ettringite in late sulfate attack. It is considered that the substitution reaction direction solely depend on the concentration of chloride and sulfate ion.

A Study on the Formation and the Change of the CDM(Clean Development Mechanism) Industry in the Republic of Korea from the Change in Industrial Networks (한국 청정개발체제 네트워크 변화에 따른 산업 형성과 변화 연구)

  • Lee, Jin-Hyung
    • Journal of the Economic Geographical Society of Korea
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    • v.20 no.4
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    • pp.486-502
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    • 2017
  • This study investigated the formation process and networks of Korean Clean Development Mechanism(CDM) industry. It aimed to reveal the factors and the drivers for the formation processes of this industry in the specific place. Based on the analysis of the Project Design Documents(PDDs) of the CDM projects and the collected project data by international institutions, surveys, and interviews were done. On the basis of these data, the analysis on the industrial change as complex emergent effects by the network evolution caused by adaptive activity of firms is conducted. In the time of the genesis, a kind of serendipity that the industrial activities of Korean firms meet to new system, CDM, In the changing process of the Korean CDM industry, the role of policies fo Korean Government was important to promote the new and renewable energy projects of the power companies. In the time of restructuring, Korean government policies formed new initial conditions for the new domestic GHGs reduction industry. In this processes, the localization of knowledge acted as a key driver for the formation of the Korean CDM industry.

Three Models of Decision-Making (의사결정의 세 가지 모델)

  • Lee, Sang-hyung
    • Journal of Korean Philosophical Society
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    • v.144
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    • pp.257-283
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    • 2017
  • The purpose of this paper is primarily to examine models of collective decision-formation and decision-making. The goal is to propose a model of decision-formation and decision-making that is appropriate for a democratic society. Habermas distinguishes these models of decision-formation and decision-making by liberal, republican, and deliberative political models according to their justification types. Axel Honneth, on the other hand, is divided into three models of liberalism, proceduralism, and republicanism. I want to divide the model of possible decision-making in democratic society into three, that is, the model based on force, the model based on procedure, and the republican model. This distinction will identify the characteristics of each decision-making model and this confirmation will help us find the best decision-making model for a democratic society. In the end, I will combine the republican model with the procedural model. For this synthesis, I will also propose three conditions in modern society. I will argue that the three conditions of collective intelligence, active freedom, and horizontal networks are necessary.