• Title/Summary/Keyword: selection

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Antenna Selection Schemes in Quadrature Spatial Modulation Systems

  • Kim, Sangchoon
    • ETRI Journal
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    • v.38 no.4
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    • pp.606-611
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    • 2016
  • This paper presents antenna selection schemes for recently proposed quadrature spatial modulation (QSM) systems. The antenna selection strategy is based on Euclidean distance optimized antenna selection (EDAS). The symbol error rate (SER) performance of these schemes is compared with that of the corresponding algorithm associated with spatial modulation (SM) systems. It is shown through simulations that QSM systems using EDAS offer significant improvement in terms of SER performance over SM systems with EDAS. Their SER performance gains are seen to be about 2 dB-4 dB in $E_s/N_0$ values.

A Study on 'Selection' in Collection Management (장서관리에 있어서 '선택'기능에 관한 연구)

    • Journal of Korean Library and Information Science Society
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    • v.30 no.4
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    • pp.1-26
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    • 1999
  • This study purposes to identify how the 'selection' of library materials shold be changed in the electronic environment to improve library services fundamentally. The study scrutinized the essence of selection, the relationship between selection and collection management, and the results of various studies to define the selection. The study implies: 1) the selection must be changed to the function providing users with assessment information of library materials, which helps the users access to entire scholarly information. 2) the assessment information could be input from different libraries and used by all users connected to the library network.

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A MISCELLANY OF SELECTION THEOREMS WITHOUT CONVEXITY

  • Kim, Hoonjoo
    • Honam Mathematical Journal
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    • v.35 no.4
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    • pp.757-764
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    • 2013
  • In this paper, we give sufficient conditions for a map with nonconvex values to have a continuous selection and the selection extension property in LC-metric spaces under the one-point extension property. And we apply it to weakly lower semicontinuous maps and generalize previous results. We also get a continuous selection theorem for almost lower semicontinuous maps with closed sub-admissible values in $\mathbb{R}$-trees.

Bayesian estimation for finite population proportion under selection bias via surrogate samples

  • Choi, Seong Mi;Kim, Dal Ho
    • Journal of the Korean Data and Information Science Society
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    • v.24 no.6
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    • pp.1543-1550
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    • 2013
  • In this paper, we study Bayesian estimation for the finite population proportion in binary data under selection bias. We use a Bayesian nonignorable selection model to accommodate the selection mechanism. We compare four possible estimators of the finite population proportions based on data analysis as well as Monte Carlo simulation. It turns out that nonignorable selection model might be useful for weekly biased samples.

Robust Variable Selection in Classification Tree

  • Jang Jeong Yee;Jeong Kwang Mo
    • Proceedings of the Korean Statistical Society Conference
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    • 2001.11a
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    • pp.89-94
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    • 2001
  • In this study we focus on variable selection in decision tree growing structure. Some of the splitting rules and variable selection algorithms are discussed. We propose a competitive variable selection method based on Kruskal-Wallis test, which is a nonparametric version of ANOVA F-test. Through a Monte Carlo study we note that CART has serious bias in variable selection towards categorical variables having many values, and also QUEST using F-test is not so powerful to select informative variables under heavy tailed distributions.

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A New Variable Selection Method Based on Mutual Information Maximization by Replacing Collinear Variables for Nonlinear Quantitative Structure-Property Relationship Models

  • Ghasemi, Jahan B.;Zolfonoun, Ehsan
    • Bulletin of the Korean Chemical Society
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    • v.33 no.5
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    • pp.1527-1535
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    • 2012
  • Selection of the most informative molecular descriptors from the original data set is a key step for development of quantitative structure activity/property relationship models. Recently, mutual information (MI) has gained increasing attention in feature selection problems. This paper presents an effective mutual information-based feature selection approach, named mutual information maximization by replacing collinear variables (MIMRCV), for nonlinear quantitative structure-property relationship models. The proposed variable selection method was applied to three different QSPR datasets, soil degradation half-life of 47 organophosphorus pesticides, GC-MS retention times of 85 volatile organic compounds, and water-to-micellar cetyltrimethylammonium bromide partition coefficients of 62 organic compounds.The obtained results revealed that using MIMRCV as feature selection method improves the predictive quality of the developed models compared to conventional MI based variable selection algorithms.

Priority Based Interface Selection for Overlaying Heterogeneous Networks

  • Chowdhury, Mostafa Zaman;Jang, Yeong-Min
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.7B
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    • pp.1009-1017
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    • 2010
  • Offering of different attractive opportunities by different wireless technologies trends the convergence of heterogeneous networks for the future wireless communication system. To make a seamless handover among the heterogeneous networks, the optimization of the power consumption, and optimal selection of interface are the challenging issues. The access of multi interfaces simultaneously reduces the handover latency and data loss in heterogeneous handover. The mobile node (MN) maintains one interface connection while other interface is used for handover process. However, it causes much battery power consumption. In this paper we propose an efficient interface selection scheme including interface selection algorithms, interface selection procedures considering battery power consumption and user mobility with other existing parameters for overlaying networks. We also propose a priority based network selection scheme according to the service types. MN‘s battery power level, provision of QoS/QoE and our proposed priority parameters are considered as more important parameters for our interface selection algorithm. The performances of the proposed scheme are verified using numerical analysis.

A study of selection operator using distance information between individuals in genetic algorithm

  • Ito, Minoru;Sugisaka, Masanori
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.1521-1524
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    • 2003
  • In this paper, we propose a "Distance Correlation Selection operator (DCS)" as a new selection operator. For Genetic Algorithm (GA), many improvements have been proposed. The MGG (Minimal Generation Gap) model proposed by Satoh et.al. shows good performance. The MGG model has all advantages of conventional models and the ability of avoiding the premature convergence and suppressing the evolutionary stagnation. The proposed method is an extension of selection operator in the original MGG model. Generally, GA has two types of selection operators, one is "selection for reproduction", and the other is "selection for survival"; the former is for crossover and the latter is the individuals which survive to the next generation. The proposed method is an extension of the former. The proposed method utilizes distance information between individuals. From this extension, the proposed method aims to expand a search area and improve ability to search solution. The performance of the proposed method is examined with several standard test functions. The experimental results show good performance better than the original MGG model.

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A Study on the Fast Fashion(Part II) - Focusing on Clothing Selection Criteria and Store Selection Criteria - (패스트 패션(Fast Fashion)에 대한 고찰(제2보) - 의복 평가 기준 및 점포 선택 기준을 중심으로 -)

  • Kim, Sun-Hee
    • The Research Journal of the Costume Culture
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    • v.15 no.5
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    • pp.888-901
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    • 2007
  • The purpose of this study was to examine the differences in clothing selection criteria and store selection criteria between each consumer groups by the preference for fast fashion. The data was collected from a questionnaire conducted on 317 female adults. The results were as follows. First, the factor analysis used to identify clothing selection criteria involved the following four factors: fashion, quality/practicality, status symbol, and economics. The consumer group preferring fast-fashion regarded fashion and economics as important factors and the non-preferring group regarded status symbol factor more. Second, five factors(atmosphere, product service/salesperson, shopping convenience, promotion/facilities) of store selection criteria were constructed by factor analysis, The consumer group preferring fast-fashion regarded atmosphere and product as important factors and the non-preferring group considered service/salesperson and promotion/facilities factors more. Third, the consumers who were of low age, low education, low income and unmarried preferred fast fashion brand.

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Cloches Selection in Accordance with Job Characteristic and Working Place Situation of A Professional Women in Industry (산업체 전문직 여성의 직무특성과 직장상황에 의한 의복선택 연구)

  • 정은숙;이선재
    • Journal of the Korean Society of Costume
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    • v.50 no.5
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    • pp.77-90
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    • 2000
  • The purpose of this study is to disclose the dimension of job characteristic, working place situation. and clothes selection, which are variable on clothes selection, to research the relation of job characteristic, working place situation, and clothes selection and to disclose the feature of consumers by each group in accordance with job characteristic. The follows are summary of this study result : The concept structure of job characteristic is composed by four types. Working place situation related with clothes selection are consisted of five types. Professional women selected clothes in accordance with nine feature. Job characteristic is related with working palace situation and influences on clothes selection. The persons influenced by activity state regarded personality as important when select clothes. The persons influenced by duty state regarded harmony and control as important, instead of, they ignored conformity. People select occupation according to individual feature, so the feature of consumers, working place environment, working place situation are different in accordance with job characteristic, as a result we can find differences in clothes selection suitable for working palace and purchasing.

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