• 제목/요약/키워드: combination method

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염료감응형 태양전지 광전류 향상을 위한 $TiO_2$ 광전극 제작방법에 관한 연구 (A study on the method of manufacturing $TiO_2$ photoelectrode for improving the photocurrent of dye-sensitized solar cells)

  • 백형렬;한정희;박경희;구할본
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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    • pp.354-355
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    • 2006
  • We manufactured photoelectrode of dye-sensitized solar cells (DSC) by using three methods such as squeeze method, spray method, and combination method (squeeze method first, spray method second). We examined how the morphology of an electrode's surface, the pore between particles, and condensation have an effect on an open-circuit voltage, photocurrent, fill factor, and energy conversion efficiency. Open-circuit voltage of dye-sensitized solar cells manufactured by using three methods is about 0.66V when the photoelectrode of the three DSCs is about $5{\mu}m$ thick. Photocurrent and fill factor and conversion efficiency of DSC manufactured by using squeeze method is 18.5 and 34 and 7.8, respectively. Photocurrent and fill factor and conversion efficiency of DSC manufactured by using spray method is 3.62 and 62 and 2.8, respectively. Photocurrent and fill factor and conversion efficiency of DSC manufactured by using combination method is 10.7 and 46 and 5.9, respectively. In conclusion, we find that the combination method is better than the other two methods in such respects as energy conversion efficiency and fill factor.

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Combination of Schwarz Information Criteria for Change-Point Analysis

  • 김종태
    • Journal of the Korean Data and Information Science Society
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    • 제13권2호
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    • pp.185-193
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    • 2002
  • The purpose of this paper is to suggest a method for detecting the linear regression change-points or variance change-points in regression model by the combination of Schwarz information criteria. The advantage of the suggested method is to detect change-points more detailed when one compares the suggest method with Chen (1998)'s method.

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층지진하중분포 예측을 위한 모드조합법 (Modal Combination Method for Prediction of Story Earthquake Load Profiles)

  • 엄태성;이혜린;박홍근
    • 한국지진공학회논문집
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    • 제10권3호
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    • pp.65-75
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    • 2006
  • 건물의 지진응답을 평가하기 위하여 비선형 푸시오버 해석을 수행한다. 구조물의 비탄성 지진응답을 정확히 예측하기 위해서는, 비선형해석에 사용되는 층하중분포가 구조물의 시간이력 지진응답 동안 실제로 발생되는 지진하중분포를 나타낼 수 있어야 한다. 본 연구에서는 건축물의 지진하중분포를 예측하기 위하여 새로운 모드조합법을 개발하였다. 개발된 모드조합법에서는 모드조합계수를 곱한 각 모드의 스펙트럼응답을 조합하여 다수의 지진하중분포를 예측한다. 모멘트 골조와 켄틸레버 벽체에 대한 변수연구를 수행하였다. 변수연구 결과를 토대로, 각 고유모드가 구조물의 지진응답에 미치는 영향을 나타내는 모드조합계수를 정의하였다. 다양한 정형 및 수직 비정형 구조물에 대하여 제안된 계수모드조합법을 적용하였다. 그 결과 제안된 모드조합법은 시간이력 응답 동안 구조물에 실제로 발생되는 지진하중분포를 정확히 예측할 수 있었다.

제산제, 소화효소제 및 생약제를 함유한 시판 복합소화효소제의 효력시험(I) : in vitro 및 초 vivo 제산력 시험 (Efficacy Test of Commercial Digestives Containing Antacids, Digestive Enzyme and Herbal Drug(I): In vitro and In vivo Evaluation)

  • 김종국;장정윤
    • Journal of Pharmaceutical Investigation
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    • 제20권3호
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    • pp.115-119
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    • 1990
  • The reaction rates, duration times and neutralizing capacities of the antacids which are frequently used in Korean market and three different commercial combination products were evaluated in vitro by Fuchs method and Johnson-duncan method, respectively. In vivo tests of combination products were determined in the fasted state of rat by Aspiration method. Comparing the result of in vitro test with that of in vivo test, the maximal pH was lowered by 2-3 value and the durational time increased by two folds in vivo test. Each antacid composition and combination products from three phamaceutical companies (A, B, and C) were studied, respectively. The duration times measured by Fuchs method were double compared to those by Johnson-Duncan method. A and C preparation maintained the pH range from 3 to 7 for 60 min by Fuchs method. In vovo test, maximum pH of A, B and C preparation was 6.50, 3.65, 2.65 and duration time of those was 200, 500, 0 min, respectively.

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A Study on the Optimum Scheme for Determination of Operation Time of Line Feeders in Automatic Combination Weighers

  • Keraita James N.;Kim Kyo-Hyoung
    • Journal of Mechanical Science and Technology
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    • 제20권10호
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    • pp.1567-1575
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    • 2006
  • In an automatic combination weigher, the line feeders distribute the product to several weighing hoppers. The ability to supply appropriate amount of product to the weighing hoppers for each combination operation is crucial for the overall performance. Determining the right duration of operating a line feeder to supply a given amount of product becomes very challenging in case of products which are irregular in volume or specific gravity such as granular secondary processed foods. In this research, several schemes were investigated to determine the best way for a line feeder to approximate the next operating time in order to supply a set amount of irregular goods to the corresponding weighing hopper. Results obtained show that a weighted least squares method (WLS) employing 10 data points is the most effective in determining the operating times of line feeders.

PSS Evaluation Based on Vague Assessment Big Data: Hybrid Model of Multi-Weight Combination and Improved TOPSIS by Relative Entropy

  • Lianhui Li
    • Journal of Information Processing Systems
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    • 제20권3호
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    • pp.285-295
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    • 2024
  • Driven by the vague assessment big data, a product service system (PSS) evaluation method is developed based on a hybrid model of multi-weight combination and improved TOPSIS by relative entropy. The index values of PSS alternatives are solved by the integration of the stakeholders' vague assessment comments presented in the form of trapezoidal fuzzy numbers. Multi-weight combination method is proposed for index weight solving of PSS evaluation decision-making. An improved TOPSIS by relative entropy (RE) is presented to overcome the shortcomings of traditional TOPSIS and related modified TOPSIS and then PSS alternatives are evaluated. A PSS evaluation case in a printer company is given to test and verify the proposed model. The RE closeness of seven PSS alternatives are 0.3940, 0.5147, 0.7913, 0.3719, 0.2403, 0.4959, and 0.6332 and the one with the highest RE closeness is selected as the best alternative. The results of comparison examples show that the presented model can compensate for the shortcomings of existing traditional methods.

에코 패션디자인에 나타난 색채 배색 연구 (The Research of Color Combination Presented in Eco Fashion Design)

  • 최정윤;이경희;김새봄
    • 복식문화연구
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    • 제20권1호
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    • pp.62-71
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    • 2012
  • The purpose of this research is to analyze the characteristics of the color combination in Eco fashion design. 532 pictures related to eco was collected through Eco brand web sites from 2008 through 2011. The characteristics for analysis include color combination and tone. The method of research is content and statistical analysis. The result of the research is summed up below. First, achromatic color was most frequently presented in Eco fashion. Also monotone color or single color combination were displayed often. Secondly, many dresses were of single color combination and T-shirt items displayed contrast color combination created by luminosity difference. Third, the outcome of comparing seasons was that both seasons presented single color and contrast color combination. The difference between countries proved slight as single color coloration dominated. This considered the process which was non-chemical manufacture for eco-friendly. For the combination of colors, the same coloration with single colors or contrast coloration due to the differences of brightness were presented quite often, generally, the modern image fashion without fancy factors have shown a lot. These results that minimalism trend was included in eco-friendly image.

Synergistic Effects of Exemestane and Aspirin on MCF-7 Human Breast Cancer Cells

  • Hu, Li-Xia;Du, Ying-Ying;Zhang, Ying;Pan, Yue-Yin
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권11호
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    • pp.5903-5908
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    • 2012
  • Objective: The purpose of this study is to investigate the combined effects of exemestane and aspirin on MCF-7 human breast cancer cells. Methods: Antiproliferative effects of exemestane and aspirin, alone and in combination, on growth of MCF-7 human breast cancer cells were assessed using the MTT assay. Synergistic interaction between the two drugs was evaluated in vitro using the combination index (CI) method. The cell cycle distribution was analyzed by flow cytometry and Western blotting was used to investigate the expression of cyclooxygenase-1, cyclooxygenase-2 and Bcl-2. Results: MTT assays indicated that combination treatment obviously decreased the viability of MCF-7 human breast cancer cells compared to individual drug treatment (CI<1). In addition, the combination of exemestane and aspirin exhibited a synergistic inhibition of cell proliferation, significantly arrested the cell cycle in the $G_0/G_1$ phase and produced a stronger inhibitory effect on COX-1 and Bcl-2 expression than control or individual drug treatment. Conclusion: These results indicate that the combination of exemestane and aspirin might become a useful method to the treatment of hormone-dependent breast cancer. The combination of the two inhibitors significantly increased the response as compared to single agent treatment, suggesting that combination treatment could become a highly effective approach for breast cancer.

제약하의 예측조합 방법을 활용한 산업별 고용비중 예측 (Prediction of the employment ratio by industry using constrainted forecast combination)

  • 김정우
    • 한국융합학회논문지
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    • 제11권11호
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    • pp.257-267
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    • 2020
  • 본 연구는 우리나라 수출 분야의 산업별 고용비중을 다양한 머신러닝 기법을 활용하여 예측하고, 예측성능을 높이기 위하여 머신러닝 기법 예측값들에 예측조합 기법을 적용하였다. 특히, 본 연구에서는 각 머신러닝 기법 예측값들에 부여되는 가중치의 합을 1로 설정하는 제약하의 예측조합 기법을 사용하여 예측의 정확성과 안정성을 확보하고자 하였다. 또한, 본 연구는 산업별 고용비중에 영향을 주는 다양한 변수를 고려하기 위하여 재귀적특성제거 방법을 사용하여 주요 변수를 선별한 후, 머신러닝 기법에 적용함으로써 예측과정 상에서의 효율성을 높였다. 분석결과, 예측조합 방법에 따른 예측값은 머신러닝 기법의 예측값들보다 실제의 산업 고용비중에 근접한 것으로 나타났으며, 머신러닝 기법의 예측값들이 큰 변동성을 보이는 것과 달리 제약하의 예측조합 기법은 안정적인 예측값을 나타내었다.

전력계통의 페이저 측정기 최적배치 (Optimal Placement of the Phasor Measurement Units in Power System)

  • 김재훈;조기선;김회철;신중린
    • 대한전기학회논문지:전력기술부문A
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    • 제49권7호
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    • pp.313-322
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    • 2000
  • This paper presents optimal placement of minimal set of Phasor Measurement Units (PMU's) and observability analysis of the network with PMU's. In order to find a observable system, a symbolic method which directly assigns an appropriate symbol for measurement or pseudo-measurement to every entry of node-branch incidence matrix is proposed. It is much simpler and easier to analyze the observability of the network with PMU's than the conventional ones. For the optimal PMU placement problem, two approaches which are based on a modified Simulated-Annealing (SA) method and a Direct Combination method are proposed. Some case studies with IEEE sample system are made to show the performance of the proposed methods are almost alike and more effective than the conventional simulated-annealing method. It is also shown that the Direct Combination method is more effective than the modified simulated-annealing one in the sense of computation burden. The results of this study showed also that the accuracy of power system estimation and system observability can be improved the proposed PMU placements.

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