• 제목/요약/키워드: Weighting average

검색결과 169건 처리시간 0.021초

원영상의 기울기 성형을 이용한 경계강조 오차확산법 (Edge Enhanced Error Diffusion based on Gradient Shaping of Original image)

  • 강태하;황병원
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 하계종합학술대회 논문집(4)
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    • pp.70-73
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    • 2000
  • The error diffusion is good for reproducing continuous image to binary image. However the reproduction of edge characteristics is weak in power spectrum analysis of display error. It is suggested for us an edge-enhanced error-diffusion method that is included pre-processing algorithm for edge characteristic enhancement. Pre-processing algorithm is organized horizontal and vertical directional 2nd order differential values and weighting function of pre-filter. The improved Error diffusion using pre-filter, presents a good results visually which edge characteristics is enhanced. The performance of the proposed algorithm is compared with that of the conventional edge-enhanced error diffusion by measuring the RAPSD of display error, the egde correlation and the local average accordance.

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Asymmetric Semi-Supervised Boosting Scheme for Interactive Image Retrieval

  • Wu, Jun;Lu, Ming-Yu
    • ETRI Journal
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    • 제32권5호
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    • pp.766-773
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    • 2010
  • Support vector machine (SVM) active learning plays a key role in the interactive content-based image retrieval (CBIR) community. However, the regular SVM active learning is challenged by what we call "the small example problem" and "the asymmetric distribution problem." This paper attempts to integrate the merits of semi-supervised learning, ensemble learning, and active learning into the interactive CBIR. Concretely, unlabeled images are exploited to facilitate boosting by helping augment the diversity among base SVM classifiers, and then the learned ensemble model is used to identify the most informative images for active learning. In particular, a bias-weighting mechanism is developed to guide the ensemble model to pay more attention on positive images than negative images. Experiments on 5000 Corel images show that the proposed method yields better retrieval performance by an amount of 0.16 in mean average precision compared to regular SVM active learning, which is more effective than some existing improved variants of SVM active learning.

OFDM 시스템에서의 GD방식과 Radix-2 DIF IFFT를 이용한 효과적인 PAPR 감소 방식 (A New PAPR Reduction Method in the OFDM System Using GD and Radix-2 Dif IFFT)

  • 이선호;이해기;김성수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 학술대회 논문집 전문대학교육위원
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    • pp.70-73
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    • 2007
  • Many methods have been developed to overcome the PAPR(peak-to-average power ratio) problem. Selective mapping(SLM) partial transmit sequence(PTS), subblock phase weighting(SPW) and gradient descent(GD) are used widely to reduce the PAPR. In this paper, we present a effective PAPR reduction method, decrease the calculation through Radix-2 DIF IFFT procedure and GD method. and can transmit selecting data sequence that satisfy threshold value as one part of proposed method, in case satisfy fixed threshold value, or transmit selecting data sequence with the lower papr operating remained part for performance improvement.

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EFFECT OF RECOMBINANT BOVINE SOMATOTROPIN ON GROWTH PERFORMANCE AND CARCASS CHARACTERISTICS OF FINISHING KOREAN NATIVE BULLS

  • Kwak, B.O.;Ha, J.K.;Chang, B.S.
    • Asian-Australasian Journal of Animal Sciences
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    • 제9권1호
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    • pp.101-106
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    • 1996
  • This experiment was conducted to investigate the effect of bST administration on growth performance and carcass characteristics of finishing Korean native bulls. Fifty four Korean native bulls of about 14 months of age weighting an average 420 kg were assigned to receive no injection of bST, 250 mg of bST s.c. injection every week, or 500 mg bST s.c. injection every 2 weeks (Control, 250ST, 500ST) in a $3{\times}3$ randomized block design for a period of 20 weeks Animals administered with bST responded with decreased feed DMI by 8%(p < 0.01), increased ADG by 12%(p < 0.05), and increased gain/feed ratio by 20%(p < 0.01). But there was no significant difference in the growth performance between 250ST and 500ST. Administration of bST increased dressing percentage by 1.8%(p < 0.05), and tended to increase longissimus muscle area and decrease backfat thickness and marbling score.

공간 데이터와 시계열 데이터로부터 유도된 공분산행렬을 결합한 강수량 결측값 추정 모형 (Development of a Model Combining Covariance Matrices Derived from Spatial and Temporal Data to Estimate Missing Rainfall Data)

  • 성찬용
    • 한국환경과학회지
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    • 제22권3호
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    • pp.303-308
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    • 2013
  • This paper proposed a new method for estimating missing values in time series rainfall data. The proposed method integrated the two most widely used estimation methods, general linear model(GLM) and ordinary kriging(OK), by taking a weighted average of covariance matrices derived from each of the two methods. The proposed method was cross-validated using daily rainfall data at thirteen rain gauges in the Hyeong-san River basin. The goodness-of-fit of the proposed method was higher than those of GLM and OK, which can be attributed to the weighting algorithm that was designed to minimize errors caused by violations of assumptions of the two existing methods. This result suggests that the proposed method is more accurate in missing values in time series rainfall data, especially in a region where the assumptions of existing methods are not met, i.e., rainfall varies by season and topography is heterogeneous.

원영상의 기울기 성형을 이용한 경계강조 오차확산법 (Edge Enhanced Error Diffusion based on Gradient Shaping of Original Image)

  • 강태하
    • 한국통신학회논문지
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    • 제25권10B호
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    • pp.1832-1840
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    • 2000
  • The error diffusion algorithm is good for reproducing continuous images to binary images. However the reproduction of edge characteristics is weak in power spectrum an analysis of display error. In this paper an edge enhanced error diffusion method is proposed to improve the edge characteristic enhancement. Spatial gradient information in original image is adapted for edge enhance in threshold modulation of error diffusion. First the horizontal and vertical second order differential values are obtained from the gradient of peripheral pixels(3x3) in original image. second weighting function is composed by function including absolute value and sign of second order differential values. The proposed method presents a good visual results which edge characteristics is enhanced. The performance of the proposed method is compared with that of the conventional edge enhanced error diffusion by measuring the edge correlation and the local average accordance over a range of viewing distances and the RAPSD of display error.

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연소시험법에 의한 산화성물질의 위험성 평가 (Risk Evaluation of Oxidizing Substances by Burning Test Method)

  • 정국삼
    • 한국안전학회지
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    • 제7권3호
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    • pp.73-82
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    • 1992
  • This paper was concerned with the risk evaluation of oxidizing substances by burning test method. The samples were prepared the heaped cone-shaped mixtures of solid oxidizing sub-stance with sawdust, and ignition of the sample was made on contact with heating wire inside the combution chamber that the temperature and humidity of atmosphere can be kept at $25^{\circ}C$ and 60% respectively. Accordingly, it were measured the combustivity effect of mixing ratio and amount of sample weight on the burning rate. As a result of burning test of these samples, it could be noticed that the case when the sawdust has so and 30 wt.% in the mixing ratio shows effective combustivity, and as the amount of sample weight was increasing, It showed more rapid burning time. So the average burning time could be obtained by considering the weighting factors to the parameters of the mixing ratio and the amount of sample weight. Finally, it was compared with the effects of cation and anion of oxidizing substances and also applied analytically to the classification and evaluation of oxidizing sub-stances as dangerous goods.

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가변 크기 문맥과 거리가중치를 이용한 동형이의어 중의성 해소 (Word sense disambiguation using dynamic sized context and distance weighting)

  • 이현아
    • Journal of Advanced Marine Engineering and Technology
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    • 제38권4호
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    • pp.444-450
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    • 2014
  • 의미 중의성 해소를 위한 대부분의 기존 연구에서는 문장의 특성에 상관없이 고정적인 크기의 문맥을 사용해 왔다. 본 논문에서는 중의성 해소에서 문장에 따라 가변적인 크기의 문맥을 사용하는 가변길이 윈도우와 단어간 거리를 사용한 의미분석 방법을 제안한다. 세종코퍼스의 형태의미분석 말뭉치로 학습하여 12단어 32,735문장에 대해 실험한 결과에서 제안된 방법이 용언에 대하여 92.2%의 평균 정확도를 보여 고정 크기의 문맥을 사용한 경우에 비해 향상된 결과를 보였다.

개별 관측치에서 지수변환을 이용한 EWMA 관리도 적용기법 (EWMA chart Application using the Transformation of the Exponential with Individual Observations)

  • 지선수
    • 산업경영시스템학회지
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    • 제22권52호
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    • pp.337-345
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    • 1999
  • The long-tailed, positively skewed exponential distribution can be made into an almost symmetric distribution by taking the exponent of the data. In these situations, to use the traditional shewhart control limits on an individuals chart would be impractical and inconvenient. The transformed data, approximately bell-shaped, can be plotted conveniently on the individuals chart and exponentially weighted moving average chart. In this paper, using modifying statistics with transformed exponential of the data, we give a method for constructing control charts. Selecting method of exponent for individual chart is evaluated. And consider that smaller weight being assigned to the older data as time process and properties and taking method of exponent($\theta$), weighting factor($\alpha$) are suggested. Our recommendation, on the basis result of simulation, is practical method for EWMA chart.

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산화성물질의 화학적 위험성 평가 (Chemical Risk Assessment of Oxidizing Substances)

  • 정국삼
    • 한국안전학회지
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    • 제8권1호
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    • pp.35-46
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    • 1993
  • This paper was concerned with the risk assessment about oxidizing substances as dangerous goods by burning test method. The sample. which was formed with the heaped cone-shape. was composed of solid oxidant and sawdust. The burning time of each sample was measured under the following various conditions circumstance temperature. mixing ratio of oxidizing substance and sawdust. particle size of sawdust and kinds of sawdust. As a results. the effective combustibility was gained when the sawdust content was 20∼30 wt.% in the sample and the lauan with -30+50 mesh was used. But. although the circumstance temperature increased. burning efficiency of the samples wet$.$e not affect by it. Finally. the average burning times were obtained by considering the weighting factors related on the mixing ratio and the circumstance temperature. And then. it were compared with the combustion risk level and the effects of cation and anion of oxidizing substances as dangerous goods.

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