• Title/Summary/Keyword: data weighting

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A Study on the Methods to Calculate Mixed Weights of the Condition Evaluation of Rock Slope (절리암반비탈면의 상태평가항목에 대한 혼합가중치 산정방법에 관한 연구)

  • Byun, Yoseph;Choi, Jungchan;Seong, Joohyun
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.22 no.6
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    • pp.37-44
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    • 2018
  • This study proposed the modified weighting values for jointed rock slopes. The studies on deduction of evaluation index and calculation of weighting, development of criteria for evaluation and evaluation models have been conducted through decision making techniques such as the Delphi method and the AHP method by many researchers. Because these decisions making techniques may be less objective, it is necessary to calculate reasonable weighting considering both an objective weighting and a subjective weighting simultaneously. In this study, utilizing the inspection data of jointed rock slopes, an objective weighting that the concept of entropy is applied was calculated. And the subjective weighting values by AHP technique was calculated based on the opinion of experts. And a modified weighting was suggested by combining the two. As a result, it was found that jointed rock slopes have higher weighting in artificial factors and the damage status items. In addition based on the finally suggested weighting (mixed weighting), the revised evaluation criteria could be presented by converting it into the evaluation score (76 points). And it is expected that it could be usefully utilized upon inspections on cutting slopes and safety diagnosis since objective and highly reliable criteria compared to the condition evaluation criteria that are currently used could be presented through the results of the study.

Design and Performance Analysis of the SPW Method for PAPR Reduction in OFDM System (OFDM 시스템에서 PAPR 처감을 위한 SPW 방식의 설계와 성능 분석)

  • 이재은;유흥균;정영호;함영권
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.14 no.7
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    • pp.677-684
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    • 2003
  • This paper addresses the subblock phase weighting(SPW) method to reduce the PAPR in OFDM system. This method divides the input block of OFDM signal into many subblocks and lower the peak power by weighting the phase of each subblocks properly. SPW method can be realized by only one IFFT. PAPR reduction performance is novelly examined when the adjacent, interleaved and random subblock partitioning schemes are used in the SPW system. The random subblock partition scheme has the most effective. More subblocks can effectively reduce the PAPR, but there is a problem that the processing time of iteration is increased. We propose a new weighting factor combination of the complementary sequence characteristic with threshold technique. OFDM data can be recovered by the inserted side information of weighting factor in the feed forward type. Also, BER performance of this SPW system is analyzed when error happens in the side information.

Using Time Use Data for Weighting Internet Survey Results (생활시간 조사를 이용한 가중치 부여방법: 인터넷 조사에 대한 적용 가능성 검토)

  • Cho, Sung-Kyum;Park, Ah-Hyun;Huh, Myung-Hoe
    • Survey Research
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    • v.12 no.2
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    • pp.145-157
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    • 2011
  • There are limitations as to how internet surveys can be used. Applying various weighting procedures has not always resulted in error reduction. A good reference survey would increase the effects of the weighting method, but it is very difficult to get a reference survey for non-demographic weighting variables, which restricts the use of internet surveys. We hypothesized that time use variables could be employed as weighting variables. The time use survey is conducted regularly by KOSTAT and includes various time-related variables. We tested our hypothesis using the 2009 survey results, which had been gathered by KOSTAT in 2009. When we applied weighting variables which were based on the 2004 time use survey results to the online version of the 2009 KOSTAT social survey, the gap between the online and off-line versions was slightly reduced. This result shows that we could use time use survey results to develop a better weighting scheme.

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Propensity Adjustment Weighting of the Internet Survey by Volunteer Panel (자원자 패널에 의한 인터넷 조사의 성향조정 가중화)

  • Huh, Myung-Hoe;Cho, Sung-Kyum
    • Survey Research
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    • v.11 no.2
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    • pp.1-28
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    • 2010
  • This paper reports the results of the 2009 Internet volunteer panel version of the social survey conducted by Statistics Korea (Korea National Statistical Office). Authors identify socio-psychological characteristics of Internet survey volunteers and present quantitative evaluation of the propensity adjustment weighting method intended to remove Internet sample bias. The nine criteria used for propensity adjustment were regions, urban/rural, gender, age, education, consumer satisfaction, views on income distribution, newspaper access and Internet news access. Propensity adjustment weighting based on the logit model and rim weights were applied to the online survey of 2,903 respondents using the face-to-face area sample data of 37,049 respondents as reference. A total of 106 items were used for evaluating the propensity adjustment weighting methods. The results showed that in 80% of survey items the propensity adjustment weighting yielded better estimates compared to simple demographic weighting. This suggests that Internet surveys by volunteer panels are useful for conducting the general social study in Korea. The reference survey data for this study contains several items on social-psychological behaviors and attitudes, is large in size and obtained by probability sampling. Thus it may be utilized in propensity adjustment of other Internet surveys.

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Unit Nonresponse Weighting Adjustment Using Regression Tree (회귀나무를 이용한 무응답 가중치 조정)

  • Kim, Se-Mi;Lee, Seok-Hun
    • Proceedings of the Korean Association for Survey Research Conference
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    • 2005.12a
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    • pp.169-183
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    • 2005
  • This paper considers formation of nonresponse weighting adjustment cell for handling unit nonresponse in sample surveys. We propose a multivariate regression tree mehtod for segmentation using the variable of interest and the estimated response probability simultaneously to construct effective nonresponse adjustment cell. One is using only response data and the other is using response and nonresponse data. These two cases are compared in terms of bias.

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An Indirect Adaptive Pole placement Controller Using a Discrete Adaptive Observer with Exponenrial Data weighting (지수 함수적 가중 특성의 적응 관측기를 이용한 간접 극배치 적응 제어기)

  • Kim, Jong-Hwan;Park, Dong-Jo;Jeon, Jeong-Yeol
    • Proceedings of the KIEE Conference
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    • 1990.07a
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    • pp.43-46
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    • 1990
  • A general scheme for a discrete adaptive observer having exponetial weighting properties is presented for a single-input single-output linear system. In this scheme, all the past measurement data are weighted esponetially both with the weighting factor and the stable matrix F. This observer is then implemented in the design of an indirect adaptive pole placement contoller. To increase nemerical stability in getting the controller parameter, a recusive algorithm is introduced. It is shown that the overall control scheme is globally stable with the persistent excition

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New Weighting Functions for the Modified CIELAB Colour-Difference Formulae (수정 CIELAB 색차식을 위한 새로운 색차 가중 함수)

  • Kim, Dong-Ho
    • Textile Coloration and Finishing
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    • v.9 no.6
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    • pp.51-57
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    • 1997
  • The lightness, chroma and hue tolerances with respect to the standard colour position in the CIELAB space have been studied in detail using the various existing data sets and the set form this study. The lightness tolerance showed a clear dependency upon the metric lightness for medium to light colour, but in the case of dark colours there was a discrepancy between the data sets. Both the chroma and hue tolerances showed dependency upon both the chroma and hue-angle and not the single dependency upon the metric chroma, as assumed in the CIE94 formula. New weighting functions were derived from the above experimental evidence, and finally a new formula, LCD(Leeds Colour Difference) was proposed. The LCD formula is nearly as simple and flexible as CIE94 but smoothes the individual weighting functions, especially for lightness tolerances for light colours and chromaticity discrimination near the blue region.

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Text Classification for Patents: Experiments with Unigrams, Bigrams and Different Weighting Methods

  • Im, ChanJong;Kim, DoWan;Mandl, Thomas
    • International Journal of Contents
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    • v.13 no.2
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    • pp.66-74
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    • 2017
  • Patent classification is becoming more critical as patent filings have been increasing over the years. Despite comprehensive studies in the area, there remain several issues in classifying patents on IPC hierarchical levels. Not only structural complexity but also shortage of patents in the lower level of the hierarchy causes the decline in classification performance. Therefore, we propose a new method of classification based on different criteria that are categories defined by the domain's experts mentioned in trend analysis reports, i.e. Patent Landscape Report (PLR). Several experiments were conducted with the purpose of identifying type of features and weighting methods that lead to the best classification performance using Support Vector Machine (SVM). Two types of features (noun and noun phrases) and five different weighting schemes (TF-idf, TF-rf, TF-icf, TF-icf-based, and TF-idcef-based) were experimented on.

Mutual Information in Naive Bayes with Kernel Density Estimation (나이브 베이스에서의 커널 밀도 측정과 상호 정보량)

  • Xiang, Zhongliang;Yu, Xiangru;Kang, Dae-Ki
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2014.05a
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    • pp.86-88
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    • 2014
  • Naive Bayes (NB) assumption has some harmful effects in classification to the real world data. To relax this assumption, we now propose approach called Naive Bayes Mutual Information Attribute Weighting with Smooth Kernel Density Estimation (NBMIKDE) that combine the smooth kernel for attribute and attribute weighting method based on mutual information measure.

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A local path planning algorithm for free-ranging mobil robot (자율 주행로봇을 위한 국부 경로계획 알고리즘)

  • Cha, Y.Y.;Gweon, D.G.
    • Journal of the Korean Society for Precision Engineering
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    • v.11 no.4
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    • pp.88-98
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    • 1994
  • A new local path planning algorithm for free-ranging robots is proposed. Considering that a laser range finder has the excellent resolution with respect to angular and distance measurements, a simple local path planning algorithm is achieved by a directional weighting method for obtaining a heading direction of nobile robot. The directional weighting method decides the heading direction of the mobile robot by estimating the attractive resultant force which is obtained by directional weighting function times range data, and testing whether the collision-free path and the copen parthway conditions are satisfied. Also, the effectiveness of the established local path planning algorithm is estimated by computer simulation in complex environment.

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