• 제목/요약/키워드: Performance Year

검색결과 2,416건 처리시간 0.032초

사우디아라비아 태양광 발전 시스템의 성능 분석 (Performance Analysis of Photovoltaic Power System in Saudi Arabia)

  • 오원욱;강소연;천성일
    • 한국태양에너지학회 논문집
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    • 제37권1호
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    • pp.81-90
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    • 2017
  • We have analyzed the performance of 58 kWp photovoltaic (PV) power systems installed in Jeddah, Saudi Arabia. Performance ratio (PR) of 3 PV systems with 3 desert-type PV modules using monitoring data for 1 year showed 85.5% on average. Annual degradation rate of 5 individual modules achieved 0.26%, the regression model using monitoring data for the specified interval of one year showed 0.22%. Root mean square error (RMSE) of 6 big data analysis models for power output prediction in May 2016 was analyzed 2.94% using a support vector regression model.

Prediction of elementary school academic performance abilities for young children's academic abilities and preparation for learning, which the mothers and the teachers rated

  • Lee, Kyoung-Jin;Park, Ji-Hee
    • International Journal of Advanced Culture Technology
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    • 제9권1호
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    • pp.136-142
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    • 2021
  • This study was conducted by researchers to compare the differences between the ratings of mothers and teachers on young children's academic ability and learning ability, and to confirm their influence on elementary school academic performance ability. This study was conducted using data from the 7th year(2 014) and 10th year(2017) of the panel study on Korean children. The analysis data were individual basic background, academic ability, preparation for learning, and academic performance ability. 600 children were used for the study. We suggests that close interaction and cooperation between mother and teacher are necessary to support young children's academic ability and learning preparation.

Relationships between Milk Yield, Post-Partum Body Weight and Reproductive Performance in Friesian × Bunaji Cattle

  • Oni, O.O.;Adeyinka, I.A.;Afolayan, R.A.;Nwagu, B.I.;Malau-Aduli, A.E.O.;Alawa, C.B.I.;Lamidi, O.S.
    • Asian-Australasian Journal of Animal Sciences
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    • 제14권11호
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    • pp.1516-1519
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    • 2001
  • The data consisted of 369 lactation records for calvings over a sixteen-year period (1972-1987) and included only cows that had normal milk records. The data were analysed using a linear model containing the fixed effects of parity, year of calving and season of calving. The least squares means${\pm}$S.E. were $1,273{\pm}58.4kg$ for milk yield, and for post-partum body weight (kg) at 2, 3 and 4 months after calving were $343.40{\pm}3.96$, $346.10{\pm}4.10$ and $352.54{\pm}4.26$, respectively. With the exception of season of calving, the effects of parity and year of calving were significant (p<0.01) on the performance of the animals. Thus, the mean-milk yields 1162, 1351 and 1350, were similar for pre-, peak- and post rainy seasons, respectively. On the other hand, as parity increased from 1 to 3, milk yield also increased, but thereafter, there was a gradual decline in milk yield. Similarly, post-partum body weight also increased with parity. However, no consistent pattern for year effect was observed which probably was a reflection of the variation in climatic conditions, or forage quality and/or availability. The phenotypic correlations between milk yield and post-partum body weights were negative and small (ranging from -0.01 to -0.08). However, high milk production in cows was associated with longer calving interval. The implications from the phenotypic correlations are suggestive of one or two possibilities. Firstly, selection for increased body weight may actually result in decreased milk yield. Also, a substantial genetic antagonism may exist between milk yield and fertility in the crossbred cows. Therefore, it is important that selection to improve milk production should take into consideration the reproductive performance of the cows.

Longitudinal music perception performance of postlingual deaf adults with cochlear implants using acoustic and/or electrical stimulation

  • Chang, Son A;Shin, Sujin;Kim, Sungkeong;Lee, Yeabitna;Lee, Eun Young;Kim, Hanee;Shin, You-Ree;Chun, Young-Myoung
    • 말소리와 음성과학
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    • 제13권2호
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    • pp.103-109
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    • 2021
  • In this study, we investigated longitudinal music perception of adult cochlear implant (CI) users and how acoustic stimulation with CI affects their music performance. A total of 163 participants' data were analyzed retrospectively. 96 participants were using acoustic stimulation with CI and 67 participants were using electrical stimulation only via CI. The music performance (melody identification, appreciation, and satisfaction) data were collected pre-implantation, 1-year, and 2-year post-implantation. Mixed repeated measures of ANOVA and pairwise analysis adjusted by Tukey were used for the statistics. As result, in both groups, there were significant improvements in melody identification, music appreciation, and music satisfaction at 1-year, and 2-year post-implantation than a pre-implantation, but there was no significant difference between 1 and 2 years in any of the variables. Also, the group of acoustic stimulation with CI showed better perception skill of melody identification than the CI-only group. However, no differences found in music appreciation and satisfaction between the two groups, and possible explanations were discussed. In conclusion, acoustic and/or electrical hearing devices benefit the recipients in music performance over time. Although acoustic stimulation accompanied with electrical stimulation could benefit the recipients in terms of listening skills, those benefits may not extend to the subjective acceptance of music. These results suggest the need for improved sound processing mechanisms and music rehabilitation.

체장기반 수산자원평가모델에 적용되는 체장-체중 관계의 연도별 변동성의 중요성 (Importance of Considering Year-to-year Variability in Length-weight Relationship in a Size-based Fish Stock Assessment)

  • 김진우;현상윤
    • 한국수산과학회지
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    • 제52권6호
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    • pp.719-724
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    • 2019
  • This study is an extension of our previous model for a size-based fish stock assessment. In the previous model, we applied an allometric length-weight relationship (W=α·Lβ) to convert lengths of fish to weights, and estimated those parameters α and β, using data about lengths and weights aggregated over years. In this study, we focused on whether consideration of temporal (e.g., year-to-year) variability in those estimates (i.e., ${\hat{\alpha}}$ and ${\hat{\beta}}$) would contributive. After calculating year-specific estimates (i.e., year-specific pairs of ${\hat{\alpha}}$ and ${\hat{\beta}}$) by applying data about lengths and weights separated by year, we evaluated the contribution of those year-specific pairs of ${\hat{\alpha}}$ and ${\hat{\beta}}$ to the performance of the size-based stock assessment model. The model with such year-to-year variability being considered (lower AIC) outperformed that with the variability being ignored (higher AIC). We illustrated this study using data on Korean chub mackerel Scomber japonicus from 2005-2017.

오정보와 심상 재연 단서가 아동의 회상 정확도에 미치는 영향 (The Effect of Misinformation and a Mental Reinstatement on Children's Recall Accuracy)

  • 강민희;최경숙
    • 아동학회지
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    • 제24권2호
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    • pp.1-14
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    • 2003
  • In this test for the effect of misinformation and mental reinstatement on accuracy of recall in children, misinformation or neutral informations was presented to each of 80 five- and 80 nine - year - old children(Total : 160). Two days later they were asked to recall original information in one of two conditions; free recall or mental reinstatement. For 5-year-old children, mental reinstatement enhanced memory performance and increased the accuracy despite the presentation of misinformation. For 9-year-old children, there was no significant difference between free recall and mental reinstatement condition. For younger children, mental reinstatement may be an effective way of enhancing memory performance.

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제4차 건설기술진흥기본계획 성과평가체계 분석에 관한 연구 (An evaluation system analysis of 4th master plan for Improvement of Construction Technology)

  • 이두헌;이교선;손태홍
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2012년도 춘계 학술논문 발표대회
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    • pp.177-180
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    • 2012
  • Korean government has developed and implemented a five-year master plan in order to enhance construction technology competitiveness and its level of development. However, without detailed assessment of past plans it is not likely to retain feasibility and sustainability of a new five-year plan, This study analyses adequacy of the 4th five-year master plan in terms of evaluation strategies such as indicators, methods, targeted performance through benchmarking various construction policies utilized by developed countries. In addition, this manuscript provides the basis structure and critical factors for establishing future construction policies or plans.

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Performance Based Seismic Design State of Practice, 2012 Manila, Philippines

  • Sy, Jose A.;Anwar, Naveed;HtutAung, Thaung;Rayamajhi, Deepak
    • 국제초고층학회논문집
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    • 제1권3호
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    • pp.203-209
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    • 2012
  • The purpose of this paper is to present the state of practice being used in the Philippines for the performance-based seismic design of reinforced concrete tall buildings. Initially, the overall methodology follows "An Alternative Procedure for Seismic Analysis and Design of Tall Buildings Located in the Los Angeles Region, 2008", which was developed by Los Angeles Tall Buildings Structural Design Council. After 2010, the design procedure follows "Tall Buildings Initiative, Guidelines for Performance-Based Seismic Design of Tall Buildings, 2010" developed by Pacific Earthquake Engineering Research Center (PEER). After the completion of preliminary design in accordance with code-based design procedures, the performance of the building is checked for serviceable behaviour for frequent earthquakes (50% probability of exceedance in 30 years, i.e,, with 43-year return period) and very low probability of collapse under extremely rare earthquakes (2% of probability of exceedance in 50 years, i.e., 2475-year return period). In the analysis, finite element models with various complexity and refinements are used in different types of analyses using, linear-static, multi-mode pushover, and nonlinear-dynamic analyses, as appropriate. Site-specific seismic input ground motions are used to check the level of performance under the potential hazard, which is likely to be experienced. Sample project conducted using performance-based seismic design procedures is also briefly presented.

DEA 분석 기법을 이용한 안전관리체제 운영효율성 분석 (A Analysis on the Operation Efficiency of Safety Management System using DEA method)

  • 양형선;김철승;노창균
    • 해양환경안전학회:학술대회논문집
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    • 해양환경안전학회 2006년도 춘계학술발표회
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    • pp.15-20
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    • 2006
  • 본 연구에서는 국내 해운회사의 안전관리를 위한 여러 가지 투입요소와 산출요소들에 대한 자료를 설문조사하고 각 해운 회사간의 안전관리체제 이행에 따른 효율성을 DEA 분석법을 사용하여 분석하였다. 1998년$\sim$2004년까지 각 해운회사의 안전관리체체의 운영효율성을 DEA 모형으로 분석한 결과 효율성 평균지수가 매년 감소하는 추세를 나타내었다. 효율성 평균지수가 매년 낮아지는 경향을 보이는 이유는 해양사고 건수, PSC 지적 건수, 선박보험료, P&I 보험료는 매 년 감소하는 것에 비해 선박수리비, 선용품비와 선박 불가동일수는 매년 감소하지 않고 오히려 증가하는 경향을 보이고 있는 것이 그 주요한 원인으로 분석되었다.

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건물일체형 투명 PV복층창의 설치조건에 따른 단위출력당 발전특성 분석연구 (A Study on the Power Performance Measurement of Transparent Thin-film PV Windows of BIPV Depending on the Inclined Angle)

  • 안영섭;송종화;김석기;이성진;윤종호
    • 한국태양에너지학회:학술대회논문집
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    • 한국태양에너지학회 2008년도 춘계학술발표대회 논문집
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    • pp.55-60
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    • 2008
  • This study is on the analysis of power output of transparent thin-film PV windows which are integrated into the building envelope instead of traditional windows. 3 installation angles of vertical, horizontal and $30^{\circ}C$ inclination are investigated. To measure power output of PV windows, full scale mock-up house was designed and constructed. The power performance of PV window system was analyzed for horizontal angle, declination angle and vertical angle according to incline angle. Monitoring data are gathered from November 2006 to August 2007 and statistical analysis is performed to analysis a characteristics of power performance of transparent PV windows. Results show that annual power output of PV window with horizontal angle is 844.4kWh/kWp/year, declination angle 1,060kWh/kWp/year and vertical angle 431.6 kWh/kWp/year.

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