• Title/Summary/Keyword: Visual analysis

Search Result 4,620, Processing Time 0.039 seconds

Spectral Estimation of EEG signal by AR Model (AR 모델을 이용한 뇌파신호의 스펙트럼 추정)

  • Ryo, D.K.;Kim, T.S.;Huh, J.M.;Yoo, S.K.;Park, S.H.
    • Proceedings of the KOSOMBE Conference
    • /
    • v.1990 no.11
    • /
    • pp.114-117
    • /
    • 1990
  • EEG signal is analyzed by two methods, analysis by visual inspection of EEG recording sheets and analysis by quantative method. Generally visual inspection method is used in the clinical field. But this method has its limitation because EEG signal is random signal. Therefore it is necessary to analyze EEG signals quantatively to obtain more precise and objective information of neural and brain. In this paper, power spectrum of EEG signal was estimated by AR(AutoRegressive) model in the frequency domain. This process is useful as a preprocessing stage for tomographic brain mapping (TBM) at each frequency, band. As a method for estimating power spectral density of EEG signals, periodogram method, autocorrelation method. covariance method, modified covariance method, and Burg method are tested in this paper.

  • PDF

Development of Optimal Design User Interface for Waveguide tee Junction using PSO Algorithm and VBA (PSO 알고리즘과 VBA를 이용한 Waveguide tee Junction의 최적설계 인터페이스 개발)

  • Park, Hyun-Soo;Byun, Jin-Kyu;Lee, Dal-Ho;Lee, Hyang-Beom
    • 한국정보통신설비학회:학술대회논문집
    • /
    • 2009.08a
    • /
    • pp.36-39
    • /
    • 2009
  • We developed an optimal design interface based on VBA(Visual Basic Application) that takes advantage of API(Application Program Interface) function of commonly used EM analysis software. The developed interface is adopted for an optimal design of a septum in a waveguide tee junction using PSO(Particle Swarm Optimization) algorithm. The objective function of the optimal design is defined by $S_{11}$-parameter of the waveguide tee junction Design variables are established as position of the septum, that are changed to satisfy the design goal Using the developed design interface and PSO algorithm, the objective function converged to the smallest value, showing the validity of the proposed method. The design interface was developed using Microsoft Excel software, enabling easy control of design parameters for user. Also, various analysis parameters can be set in the Excel interface, including waveguide input mode and frequency. After completion of the design, field solutions at user-specified positrons can be extracted to the output files in complex number form.

  • PDF

A Comparison of Landscape Evaluation between the Internet and Slide Method (인터넷과 슬라이드를 이용한 경관평가방법의 비교)

  • Huh, Joon
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.29 no.5
    • /
    • pp.20-27
    • /
    • 2001
  • The purpose of this study is to investigate and compare the validity and the reliability of the visual simulation method using the internet. For this. the evaluation of the artificial and natural landscape through the medium of color slides are compared with the internet survey. Data is analysed through the comparison of t-test between the two media by landscape type, and spatial image is analysed by factor analysis algorithm. Principle component analysis using Varimax Method is applied for extraction and factor rotation respectively. The results of this study can be summarized as follows; There are no statistical differences between the two methods with artificial and natural landscape in the total data that included second tests. Factors covering the spatial image are found to be \`aesthetic\`, \`spatial shape\`, and \`familiarity\`. Total variance is obtained as 66.4%. There are no statistical differences between the two methods in 2/3 of the cases. In the case of far view of artificial landscape, the results of the t-test show that the two methods are exactly the same. Especially in the case of the artificial far landscape shows no difference of all factors between two methods. There are no differences between first and second tests of the same media and the same landscape type. And it shows the reliability of this method. These results suggest that the probability that the internet can be used as a medium of landscape evaluation and gathering information on anyone\`s landscape image. Simulation techniques with the internet survey method should be further developed for practical application.

  • PDF

Optimal Design of the Composite Hat-shaped Stiffeners for Simplified Wing Box with Embedded Array Antenna (어레이 안테나 장착을 위한 단순화된 주익 구조의 복합재 모자형 보강재 최적설계)

  • Park, Sunghyun;Kim, In-Gul;Lee, Seokje;Jun, Oo-Chul
    • Composites Research
    • /
    • v.25 no.6
    • /
    • pp.224-229
    • /
    • 2012
  • The structural performance is degraded in case of embedding the array antenna for reconnaissance and surveillance into the wing skin structures. In this paper, the optimal design for the thickness of composite hat-shaped stiffener which is reinforced embedded array antenna on the simplified composite wing box was conducted. To select the basic shape of hat-shaped stiffener, structural analysis was carry out using the commercial finite element analysis program while changing the web slope and flange length of hat-shaped stiffener. The optimal thickness of the composite hat-shaped stiffeners was determined by using commercial optimization program such as VisualDOC and commercial FEA program with considering stresses and buckling constraints.

A Study on the Structure of Intelligence Measured by the K-WPPSI-IV (한국 웩슬러 유아지능검사 4판(K-WPPSI-IV)의 지능구조에 관한 연구)

  • Lee, KyungOk;Park, Hyewon;Lee, Sanghee
    • Korean Journal of Child Studies
    • /
    • v.37 no.6
    • /
    • pp.107-117
    • /
    • 2016
  • Objective: This study examined the construct validity of K-WPPSI-IV. Factor structures of the structures of the K-WPPSI-IV full scale as well as primary index scales for two age ranges (2 years, 6 months to 3 years, 11 months; 4 years to 7 years, 7 months) were examined. Methods: Data were collected from 1,700 children aged 2 years, 6 months to 7 years, 7 months during the K-WPPSI-IV standardization. Confirmatory factor analyses were conducted using the K-WPPSI-IV subtest performances with maximum likelihood estimation using Amos 18. Results: First, the three-factor model (verbal comprehension, visual spatial, and working memory) fitted best for the younger age range. However, the five-factor model (verbal comprehension, visual spatial, fluid reasoning, working memory, and processing speed) fitted best for the older age range. Residuals suggest the presence of two nested subfactors within the verbal comprehension factor (broad/expressive and focused/simple). Second, the confirmatory factor analysis on primary index subtests identified factors that account for the intercorrelations among the reduced sets of primary index subtests. Conclusion: The findings showed that the theoretical structures of WPPSI-IV subtests were confirmed within K-WPPSI-IV.

Fluid Simulation Control for Effective VFX Underwater Explosion Effects (효과적인 VFX 수중 폭발효과 구현을 위한 유체 시뮬레이션 제어)

  • Hwang, Min Sik;Lee, Hyunseok
    • Journal of Korea Multimedia Society
    • /
    • v.20 no.9
    • /
    • pp.1606-1618
    • /
    • 2017
  • The explosion effect of computer graphics Visual Effects(VFX) used in films and animations is an important element that determines the completeness of the film, and its usage is getting extended. The realistic explosion effect of VFX should be made according to observations and analysis of various factors of actual explosion in real world. This experimental research would suggest the efficient production guideline for the technical characteristics of underwater explosion of VFX. For this research process, first, the comparison of actual explosion and VFX explosion effect, classification of actual explosion, and characteristics of underwater explosion effect will be addressed. Second, based on the literature reviews, the four steps of experimental production analysis tool will be derived. Third, the experimental research will be processed in along with technical factors four steps of the underwater explosion effect, (1)realistic creation and emission of fluid, (2)fluid expansion control by water pressure, (3)bubble effect, and (4)motion of bubble & dissipation of fluid. The effective method of fluid simulation production will be verified through experimental studies based on the characteristics of the actual explosion process. This experimental study suggested the VFX production technique is expected to be used as the basic data for related research field.

The Image and Preference Comparison between 'Opened Landscape' and 'Filtered Landscape' - Focused on With and Without Parallax Effect - ('열린경관'과 '가려진경관'의 이미지와 선호도 비교 - 패럴랙스(Parallax) 효과 유무를 중심으로 -)

  • Rho, Jae-Hyun
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.35 no.4
    • /
    • pp.105-118
    • /
    • 2007
  • The purpose of this study is not only to compare between 'Opened Landscape' and 'Filtered Landscape' image and preference but also to suggests a guide line of planting design for progressive realization. For this, the image structures of photo-sketch simulation for parallax landscape have been investigated by Semantic Differential scale(S.D. scale) and the Factor analysis. The results could be summarized as follows. The results of S.D. scale values for landscape through parallax were greater than non-parallax landscape. The scenes through parallax were better preferred to direct view. Thus the results of photo-sketch simulation test support the expected hypothesis that the visual environment of complexity and variety is closely correlated with the parallax effect and monotonous or non-parallax environment, and parallax effect on close view more bigger than the distant view. Factors covering the spatial image of parallax landscape were found to be seven and Total values were 60.35 %. The most important factors determining the parallax effect were Factors I 'depth of space' and VI 'expectation of space and interest'. An outstanding view must be handled properly to be preserved or accentuated. In this sense, the parallax spatial beauty with tree could be improved through the visual aspects of plan arrangements and the progressive realization appeared to be one effective design technique for landscape planning and design.

Development of Multi Layered Elastic Pavement Analysis Program Package Considering Temperature Nonlinearty of Asphalt Layer on GUI Environment (아스팔트층 온도 비선형성을 고려한 사용자 편의환경의 다층탄성 프로그램 개발)

  • Choi, Jun-Seong;Seo, Joo-Won;Park, Keun-Bo;Kim, Soo-Il
    • International Journal of Highway Engineering
    • /
    • v.10 no.4
    • /
    • pp.91-101
    • /
    • 2008
  • A multi layered elastic analysis program, IDYSPAP, was developed. The objective of this study was to develop the IDYSPAP program on Graphic User Interface environment for field engineers using Visual Basic, which was considered span of multi-wheels and maximum 4 axles using superposition of linear elastic theorem. It is suggested that this study considers algorithm with dynamic properties of asphalt layer on various temperature and non-linear properties of subbase and subgrade on stress non-linearity for asphalt pavement structure. This Program was modified to divide asphalt layer automatically according to layer division concept. The developed program was verified with initial measuring data in test road sections of KEC (Korea Expressway Co.) using laboratory test results.

  • PDF

Emotional and autonomic responses to IAPS-based stimulation : Effects of 1/f music and white noise on electrodermal and cardiorespiratory variables during the post-stress recovery (국제정서사진체계 ( IAPS ) 를 이용한 정서 및 자율신경계 반응 연구 : 1/f 음악 및 white noise가 스트레스 회복단계에서의 피부전기반응 및 심박호흡계 반응에 미치는 영향)

  • ;Estate Sokhadze
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
    • /
    • 1997.11a
    • /
    • pp.228-232
    • /
    • 1997
  • The special interest should be paid to the analysis of the influences of positive emotions in terms of their possible effects on the dyanmics of autonomic. recovery after the negative affective stimualtion. Taking into account emotion-specific autonomic response patterning and dissociation of parameters of autonomic arousal during experience of both positive and negative emotional states, this problem seems a challenging one. In present study several autonomic parameters were analyzed altogether, namely inedices of electrodermal activity, heart rate and respitation rate during consecutive combination or both IAPS-based visual affective and auditory stimulation. The aim of the study was analysis of patterns of electrodermal and cardiorespiratory responses during emotional states evoked by negative affective visual stimulation followed by positive or neutral auditory one with intention to identify if the latter is able to facilitate post-stress recovery and enhance restoration of pre-arousal levels. The main orientation was dirdcted towards the further application of experimentally induced comfort emotions for dampening the negative consequences of exposure to stressful stimuli.

  • PDF

Mathematics as a Communication in Elementary School Mathematics Textbooks (초등학교 수학교과서에 나타난 의사소통으로서의 수학)

  • Jeong, Eun-Sil
    • School Mathematics
    • /
    • v.14 no.3
    • /
    • pp.377-394
    • /
    • 2012
  • The purpose of this paper is to analyze the elementary school mathematics textbooks according to the mathematics curriculum revised in 2007 which put emphasis on mathematics as a communication, and to find out the implication for improving the mathematics textbook of Korea. Mathematics textbooks are analyzed by five analysis criteria, which are suitability of communication activities, suitability of usage of terms and symbols, suitability of literary expressions, suitability of visual expressions and adequateness of mathematics and curriculum. As a result of analysis, it is found out that communication activities were generally reflected the intent of curriculum but there were incomplete terms usage and literary, visual expressions. So communication among authors, between authors and writers, authors and illustrators is necessary for improvement of mathematics textbooks.

  • PDF