• Title/Summary/Keyword: Common spatial pattern

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Filter-Bank Based Regularized Common Spatial Pattern for Classification of Motor Imagery EEG (동작 상상 EEG 분류를 위한 필터 뱅크 기반 정규화 공통 공간 패턴)

  • Park, Sang-Hoon;Kim, Ha-Young;Lee, David;Lee, Sang-Goog
    • Journal of KIISE
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    • v.44 no.6
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    • pp.587-594
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    • 2017
  • Recently, motor imagery electroencephalogram(EEG) based Brain-Computer Interface(BCI) systems have received a significant amount of attention in various fields, including medicine and engineering. The Common Spatial Pattern(CSP) algorithm is the most commonly-used method to extract the features from motor imagery EEG. However, the CSP algorithm has limited applicability in Small-Sample Setting(SSS) situations because these situations rely on a covariance matrix. In addition, large differences in performance depend on the frequency bands that are being used. To address these problems, 4-40Hz band EEG signals are divided using nine filter-banks and Regularized CSP(R-CSP) is applied to individual frequency bands. Then, the Mutual Information-Based Individual Feature(MIBIF) algorithm is applied to the features of R-CSP for selecting discriminative features. Thereafter, selected features are used as inputs of the classifier Least Square Support Vector Machine(LS-SVM). The proposed method yielded a classification accuracy of 87.5%, 100%, 63.78%, 82.14%, and 86.11% in five subjects("aa", "al", "av", "aw", and "ay", respectively) for BCI competition III dataset IVa by using 18 channels in the vicinity of the motor area of the cerebral cortex. The proposed method improved the mean classification accuracy by 16.21%, 10.77% and 3.32% compared to the CSP, R-CSP and FBCSP, respectively The proposed method shows a particularly excellent performance in the SSS situation.

Displacement Measurement of Multi-Point Using a Pattern Recognition from Video Signal (영상 신호에서 패턴인식을 이용한 다중 포인트 변위측정)

  • Jeon, Hyeong-Seop;Choi, Young-Chul;Park, Jong-Won
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2008.11a
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    • pp.675-680
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    • 2008
  • This paper proposes a way to measure the displacement of a multi-point by using a pattern recognition from video signal. Generally in measuring displacement, gab sensor, which is a displacement sensor, is used. However, it is difficult to measure displacement by using a common sensor in places where it is unsuitable to attach a sensor, such as high-temperature areas or radioactive places. In this kind of places, non-contact methods should be used to measure displacement and in this study, images of CCD camera were used. When displacement is measure by using camera images, it is possible to measure displacement with a non-contact method. It is simple to install and multi-point displacement measuring device so that it is advantageous to solve problems of spatial constraints.

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Real-time BCI for imagery movement and Classification for uncued EEG signal (상상 움직임에 대한 실시간 뇌전도 뇌 컴퓨터 상호작용, 큐 없는 상상 움직임에서의 뇌 신호 분류)

  • Kang, Sung-Wook;Jun, Sung-Chan
    • 한국HCI학회:학술대회논문집
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    • 2009.02a
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    • pp.2083-2085
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    • 2009
  • Brain Computer Interface (BCI) is a communication pathway between devices (computers) and human brain. It treats brain signals in real-time basis and discriminates some information of what human brain is doing. In this work, we develop a EEG BCI system using a feature extraction such as common spatial pattern (CSP) and a classifier using Fisher linear discriminant analysis (FLDA). Two-class EEG motor imagery movement datasets with both cued and uncued are tested to verify its feasibility.

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A Study on the Spatial Generative Process in Francesco Borromini's Architecture (프란세스코 보로미니의 건축에서 나타나는 공간생성 방식에 관한 연구)

  • Kim, Hong-Su;Jung, In-Ha
    • Journal of architectural history
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    • v.14 no.2 s.42
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    • pp.71-88
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    • 2005
  • This study aims at clarifying the spatial generative process of Borromini's architecture. The close examination of his sketches and the analysis of his major four works such as San Carlo alle Quattro Fontane (1634-1667), Sant'Ivo della Sapienza (1642-1660), Santa Maria dei Sette Dolori, Chapel (1643-1646), Collegio di Propaganda Fide, Chapel (1652-1667) show common features in the generation of space as follow. 1) The spatial generative process of Borromini's architecture is dominated by the plan of main space which is formulated from simple geometric elements into complexly folded space by mean of union, addition, copy and warping. 2) Borromini made various kinds of annexed space around the main space to create long and continuous circulation. 3) Borromini's architecture has a tendency to divide interior elevation into two parts, wall part and roof part by thick entablature. Moreover the entablature play important role to copy the figure of the plan of main space three-dimensionally. 4) Borromini tried to create the sense of depth through perspectival distortion and multi-focal space through the ceiling pattern.

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Performance Evaluation of EEG-BCI Interface Algorithm in BCI(Brain Computer Interface)-Naive Subjects (뇌컴퓨터접속(BCI) 무경험자에 대한 EEG-BCI 알고리즘 성능평가)

  • Kim, Jin-Kwon;Kang, Dae-Hun;Lee, Young-Bum;Jung, Hee-Gyo;Lee, In-Su;Park, Hae-Dae;Kim, Eun-Ju;Lee, Myoung-Ho
    • Journal of Biomedical Engineering Research
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    • v.30 no.5
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    • pp.428-437
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    • 2009
  • The Performance research about EEG-BCI algorithm in BCI-naive subjects is very important for evaluating the applicability to the public. We analyzed the result of the performance evaluation experiment about the EEG-BCI algorithm in BCI-naive subjects on three different aspects. The EEG-BCI algorithm used in this paper is composed of the common spatial pattern(CSP) and the least square linear classifier. CSP is used for obtaining the characteristic of event related desynchronization, and the least square linear classifier classifies the motor imagery EEG data of the left hand or right hand. The performance evaluation experiments about EEG-BCI algorithm is conducted for 40 men and women whose age are 23.87${\pm}$2.47. The performance evaluation about EEG-BCI algorithm in BCI-naive subjects is analyzed in terms of the accuracy, the relation between the information transfer rate and the accuracy, and the performance changes when the different types of cue were used in the training session and testing session. On the result of experiment, BCI-naive group has about 20% subjects whose accuracy exceed 0.7. And this results of the accuracy were not effected significantly by the types of cue. The Information transfer rate is in the inverse proportion to the accuracy. And the accuracy shows the severe deterioration when the motor imagery is less then 2 seconds.

Spatial Econometrics Analysis of Fire Occurrence According to Type of Facilities (시설물 유형에 따른 화재 발생의 공간 계량 분석)

  • Seo, Min Song;Yoo, Hwan Hee
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.37 no.3
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    • pp.129-141
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    • 2019
  • In recent years, fast growing cities in Korea are showing signs of being vulnerable to more disasters as their population and facilities increase and intensify. In particular, fire is one of the most common disasters in Korea's cities, along with traffic accidents. Therefore, in this study, we analyze what type of factors affect the fire that threatens urban people. Fire data were acquired for 10 years, from 2007 to 2017, in Jinju, Korea. Spatial distribution pattern of fire occurrence in Jinju was assessed through the spatial autocorrelation analysis. First, spatial autocorrelation analysis was carried out to grasp the spatial distribution pattern of fire occurrence in Jinju city. In addition, correlation and multiple regression analysis were used to confirm spatial dependency and abnormality among factors. Based on this, OLS (Ordinary Least Square) regression analysis was performed using space weighting considering fire location and spatial location of each facility. As a result, First, LISA (Local Indicator of Spatial Association) analysis of the occurrence of fire in Jinju shows that the most central commercial area are fire department, industrial area, and residential area. Second, the OLS regression model was analyzed by applying spatial weighting, focusing on the most derived factors of multiple regression analysis, by integrating population and social variables and physical variables. As a result, the second kind of neighborhood living facility showed the highest correlation with the fire occurrence, followed by the following in the order of single house, sales facility, first type of neighborhood living facility, and number of households. The results of this study are expected to be useful for analyzing the fire occurrence factors of each facility in urban areas and establishing fire safety measures.

Linking Spatial Characteristics of Forest Structure and Burn Severity (산림 공간구조 특성과 산불 연소강도와의 관계에 관한 연구)

  • Lee, Sang-Woo;Lim, Joo-Hoon;Won, Myoung-Su;Lee, Joo-Mee
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.12 no.5
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    • pp.28-41
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    • 2009
  • Because fire has significant impacts on fauna and flora in forest ecosystems, as well as socioeconomic influences to local community, it has been an important field of study for decades. One of the most common ways to reduce fire risk is to enhance fire-resilience of forest through fuel treatments including thinning and prescribed burning. Since fuel treatment can't be practiced over all forested areas, appropriate and effective strategies are needed. The present study aims to look at the relationship between spatial characteristics of forest structure measured with landscape pattern metrics and burn severity to provide guidelines for effective fuel treatments. Samchuck fire was selected for the study, and 232 grids covering the study areas were generated, and the grid size was 1km. The burn severity is measured with dNBR derived from satellite imagery, and spatial characteristics of forest structure were measured using FRAGSTATS for both landscape and class levels for each 1km grid. The results of this study strongly indicated that heterogeneity in composition and configuration of forests may significantly reduce burn severity. By enhancing heterogeneity of forests, fuel treatments for fire-resilience forest could be more effective.

An Analysis on the Effects of Mathematics Learning through Tessellation Activities on Spatial Sense (테셀레이션(Tessellation)을 활용한 수학학습이 공간감각능력에 미치는 효과 분석)

  • Park, Hyun-Mee;Kang, Shin-Po;Kim, Sung-Joon
    • Journal of Elementary Mathematics Education in Korea
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    • v.11 no.2
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    • pp.117-136
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    • 2007
  • The purpose of this study was to analyze the effects of mathematics learning through tessellation activities on the improvement of spatial sense and to find out a better mathematics teaching method that could further develop spatial sense. For this purpose, the following questions were attempted; Can mathematics learning using tessellation activities develop spatial sense? In odor to test this hypothesis, twenty-four fifth graders of a class were selected at random. And the experimental group was divided into four groups according to gender and academic performance. The groups were protested and post-tested to determine results based on the quasi-experimental design(i.e. one-group pretest-post test design). The process of this study was checking spatial sense for a common evaluation of experimental group. In this study, tangram, pattern block, and GSP was used for mathematics learning through tessellation activities during each independent-study, discretion-activity, and math class. The instrument used in this study was a spatial sense test and pretest and post-test were implemented with the same instrument(i.e. K-WISC-III Activity Test). In conclusion, mathematics learning through tessellation activities with tangram, pattern block, and GSP is an effective teaching and learning method for the improvement of the spatial sense.

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Distribution Pattern of Pinus densiflora and Quercus Spp. Stand in Korea Using Spatial Statistics and GIS (공간통계와 GIS를 이용한 소나무림과 참나무류림의 분포패턴)

  • Lee, Chong-Soo;Lee, Woo-Kyun;Yoon, Jeong-Ho;Song, Chul-Chul
    • Journal of Korean Society of Forest Science
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    • v.95 no.6
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    • pp.663-671
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    • 2006
  • This study was performed for exploring the spatial distribution pattern of Pinus densiflora and Quercus spp. in Korea. Firstly, the spatial distribution map of Pinus densiflora and Quercus spp. was prepared in grid of $100m{\times}100m$ at national level, using digital forest type map and actual vegetation map. And thematic maps for topography, climate, and soil were also prepared in the raster form of $100m{\times}100m$. Through GIS based spatial analysis of the digital distribution map of Pinus densiflora and Quercus spp. and thematic maps, the spatial characteristics of Pinus densiflora and Quercus spp. distribution was explored in relation to the environmental factors such as topography, climate, and soil. And the occurrence frequency models of Pinus densiflora and Quercus spp. were derived. Pinus densiflora occurs more often than Quercus spp. at low elevation, low slope gradient, and high temperature areas. In addition, Pinus densiflora is mainly distributed at shallow and well-drained loamy soil from igneous rocks. In contrast, Quercus spp. is more common at shallow and well-drained loamy soil from metamorphic rocks. As a result, the prediction model for the spatial distribution of Pinus densiflora and Quercus spp. by topographical variables has proven successful with high statistical significance. The result of this study can contribute to rational management of Pinus densiflora and Quercus spp. stand in Korea, considering environmental factors such as topography, climate, and soil.

A Study on the Characteristics of Residential Space Use and Furniture Arrangements according to Child Age - With Priority Given to One-child Double-income Families in 3 Bed-room Apartments - (자녀 연령에 따른 주거공간의 사용 및 가구배치 특성에 관한 연구 - 3침실형 아파트에 거주하는 1자녀 맞벌이 가정을 중심으로 -)

  • Chong, Kyong-Suk;Kang, Hye-Yoen;Lee, Eunjoo
    • Korean Institute of Interior Design Journal
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    • v.25 no.5
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    • pp.93-102
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    • 2016
  • Currently, there is a gradual increase in double-income households in our country, and one-child families gradually become the norm as well due to a decrease in the birth rate. The purpose of this study was to examine the characteristics of spatial use and furniture arrangements in the residential spaces of one-child double-income households in an effort to be of use for spatial planning suitable for their living. 30 cases of double-income households whose children's ages ranged from infancy to secondary school years were visited to have in-depth interviews and make on-site inspections. The findings of the study were as follows: First, the most common spatial use pattern for three bedrooms was using one for the parents, another for their child and the third for personal computers and clothing storage. It signified that the parents and their child used one room respectively, and that there were personal computers and clothing in the third room. Second, as for the pattern of using the rooms according to furniture arrangements, there were great disparities in that regard according to child age. It implies that there were differences in their living and needs for furniture arrangements according to their children's growth. The findings of the study made it possible to determine the state of living in the double-income households in detail, and suggest that differentiated house planning is required depending on children's age groups.