• Title/Summary/Keyword: Coherence 분석

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Image Retrieval Using the Color Co-occurrence Histogram Describing the Size and Coherence of the Homogeneous Color Region (칼라 영역의 크기와 뭉침을 기술하는 칼라 동시발생 히스토그램을 이용한 영상검색)

  • An Myung-Seok;Cho Seok-Je
    • The KIPS Transactions:PartB
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    • v.13B no.3 s.106
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    • pp.275-282
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    • 2006
  • For the efficient image retrieval, the method has studied that uses color distribution and relations between pixels. This paper presents the color descriptor that stands high above the others in image retrieval capacity. It is based on color co-occurrence histogram that the diagonal part and the non-diagonal part are attached the weight and modified to energy of color co-occurrence histogram, and the number of bins with petty worth have little influence is curtailed. It's verified by analysis that the diagonal part carries size information of homogeneous color region and the non-diagonal part does information about the coherence of it, Moreover the non-diagonal part is more influential than diagonal part in survey of similarity between images. So, the non-diagonal part is attached more weight than the diagonal part as a result of the research. The experiments validate that the proposed descriptor shows better image retrieval performance when the weight for non-diagonal part is set to the value between 0.7 and 0.9.

A Study on the Processes of Elaborating Hypotheses in Abductive Inquiry of Preservice Elementary School Teachers (예비 초등 교사들의 귀추적 탐구 활동에서 가설의 정교화 과정에 관한 연구)

  • Oh, Phil-Seok;Oh, Sung-Jin
    • Journal of The Korean Association For Science Education
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    • v.31 no.1
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    • pp.128-142
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    • 2011
  • The goal of this study was to investigate how hypotheses were elaborated after their initial appearances in the context of scientific problem solving. Data were collected from a class in which preservice elementary school teachers in groups carried out abductive inquiry of earth science. The analysis revealed two major processes of hypothesis elaboration: theory-driven and evidence-driven. The theory-driven process was in turn distinguished into two kinds of subprocesses: one is in pursuit of internal coherence and the other external coherence. The evidencedriven elaboration also had two subprocesses, which were triggered by direct evidence and indirect or analogical evidence, respectively. In addition, hypotheses were more often than not modified by a wrong theory or evidence whether it was driven by a theory or evidence. Implications for science education and related research were discussed.

Total-internal-reflection Holographic Photo-lithography by Using Incoherent Light (비가간섭광을 이용한 내부전반사 홀로그래픽 리소그라피)

  • Lee, Joon-Sub;Park, Woo-Jae;Lee, Ji-Whan;Song, Seok-Ho;Lee, Sung-Jin
    • Korean Journal of Optics and Photonics
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    • v.20 no.6
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    • pp.334-338
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    • 2009
  • Recently, with increasing demand for flat-panel display product, methods for large area patterning are required. TIR (total internal reflection) holographic photo-lithography isstudied as one of the methods of large area lithography. In conventional TIR holography, light sources for hologram recording and image reconstruction are coherent beams such as laser beams. If the image is reconstructed with an incoherent light source such a UV lamp, the image noise from the coherence of light will be reduced and the UV lamp will be a better light source for large area exposure. We analyzed the effect of spectral bandwidth and angular bandwidth of the light source in image reconstruction and verified image blurring with experiments. For large area patterning which has micro-scale line width, it is expected that TIR holographic photo lithography by UV lamp will become a low-noise and low-priced technique.

A Study on the Relationship between Color and Cardiovascular Parameters (색채 감성에 대한 심혈관 변수 관계성에 대한 연구)

  • Cho, Ayoung;Woo, Jincheol;Lee, Hyunwoo;Jo, Youngho;Whang, Mincheol
    • Science of Emotion and Sensibility
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    • v.20 no.4
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    • pp.127-134
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    • 2017
  • Color is a significant factor for evoking human emotion. Therefore, the effects of color have been analyzed to predict and evaluate human emotion. The purpose of this study was to measure the cardiovascular responses depending on color stimuli in order to observe differences in color-emotions. Images consisting of six colors (red, green, blue, cyan, magenta, yellow) were used as visual stimuli. 26 college or graduate students (13 males) watched the color stimuli on the monitor and scored their subjective emotion while electrocardiogram (ECG) was meausred. The effects of the color on emotion were tested using Kruskal-Wallis test and Mann-Whitney U test. The coherence ratio showed significant differences between green and magenta (p = .004), green and red (p = .006), and green and yellow (p = .004). The significant differences of cardiovascular and emotions were relevant to emotional valence. This study shows significance as an empirical study by indicating that green induces pleasant and red induces unpleasant.

Computational performance and accuracy of compressive sensing algorithms for range-Doppler estimation (거리-도플러 추정을 위한 압축 센싱 알고리즘의 계산 성능과 정확도)

  • Lee, Hyunkyu;Lee, Keunhwa;Hong, Wooyoung;Lim, Jun-Seok;Cheong, Myoung-Jun
    • The Journal of the Acoustical Society of Korea
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    • v.38 no.5
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    • pp.534-542
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    • 2019
  • In active SONAR, several different methods are used to detect range-Doppler information of the target. Compressive sensing based method is more accurate than conventional methods and shows superior performance. There are several compressive sensing algorithms for range-Doppler estimation of active sonar. The ability of each algorithm depends on algorithm type, mutual coherence of sensing matrix, and signal to noise ratio. In this paper, we compared and analyzed computational performance and accuracy of various compressive sensing algorithms for range-Doppler estimation of active sonar. The performance of OMP (Orthogonal Matching Pursuit), CoSaMP (Compressive Sampling Matching Pursuit), BPDN (CVX) (Basis Pursuit Denoising), LARS (Least Angle Regression) algorithms is respectively estimated for varying SNR (Signal to Noise Ratio), and mutual coherence. The optimal compressive sensing algorithm is presented according to the situation.

Atomic Coherence Spectroscopy in the Paraffin Coated Rb Atom Vapor Cell (파라핀 코팅된 Rb원자 증기 셀에서 원자결맞음 분광)

  • Lee, Hyun-Joon;Yu, Ye-Jin;Bae, In-Ho;Moon, Han-Seb
    • Korean Journal of Optics and Photonics
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    • v.19 no.4
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    • pp.334-340
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    • 2008
  • We investigated the electromagnetically induced transparency (EIT) and the Hanle spectrum in a paraffin coated Rb vapor cell. The EIT spectrum was observed in the $F_g=2$, $3{\rightarrow}F_e=3$ transition of the $^{85}Rb$ $D_1$-line by using two independent external cavity diode lasers, and the Hanle spectrum was observed by using one external cavity diode laser in the $\Lambda$-type scheme between the Zeeman sublevels of the $F_g=2{\rightarrow}F_e=1$ transition of the $^{87}Rb$ $D_1$-line. In the Hanle spectrum, we could observe the dual-structured spectrum in the paraffin coated vapor cell. We investigated the dual-structured lineshape by applying an external magnetic field, and varying the direction of the magnetic field. The narrow linewidth of dual-structured EIT was measured to be approximately 200 Hz.

Terminological Misuses and Institutional Coherence in Electoral Systems (선거제도의 개념 오용과 정합성: 비례대표성을 중심으로)

  • Kim, Chae-Han
    • Korean Journal of Legislative Studies
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    • v.25 no.3
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    • pp.5-31
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    • 2019
  • In the process of changing the Korean electoral system, various terms such as representation, majority, minority, plurality, and proportionality are not used correctly, making normative judgment on its desirable electoral system difficult. This paper clarifies the concepts and terminology related to the electoral system in order to enable proper normative discussion. First, the misuse of the names of the electoral system is reviewed. This includes the majority representative system versus the minority representative system, the single-member constituency versus the multi-member constituency, the absolute majority system versus the relative majority system, and the majority representative system versus the proportional representative system. Next, the principles of representation, proportionality, democracy, direct ballot, and equal ballot are discussed to evaluate the decisions made by the Constitutional Court of Korea. In the current electoral system of the National Assembly, the equivalence between its constituency member and its proportional representation member is very low in terms of proportionality between votes received and seats allotted. Finally, the coherence between proportional representation and other political institutions is examined. Strengthening the proportionality of parliamentary elections alone does not necessarily increase the proportionality of the entire power structure.

The Effect of 4M Learning Cycle Teaching Model based on the Integrated Mental Model Theory: Focusing on Learning Circular Motion of High School Students (통합적 정신모형 이론에 기반한 4M 순환학습 수업모형의 효과: 고등학생의 원운동 관련 기초 개념과 정신모형의 발달 측면에서)

  • Park, Ji-Yeon;Lee, Gyoung-Ho
    • Journal of The Korean Association For Science Education
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    • v.28 no.4
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    • pp.302-315
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    • 2008
  • Circular motion has been one of the most difficult concepts for students to understand. To facilitate for students to form scientific mental models about circular motion, this study developed 4M learning cycle teaching model based on the integrated mental model theory and strategies. For this study, fifty-three eleventh graders at a technical high school in Inchon were taught for 3 class hours. We conducted tests of basic physics concept and mental model of circular motion before, after, and two months after instruction. In results, we found that there were statistically significant improvement in the test of basic physics concept and mental model related with circular motion after instruction. Especially, this teaching model affected learning effectiveness of Correctness and Coherence of mental model.

Evaluation on Spectral Analysis in ALOS-2 PALSAR-2 Stripmap-ScanSAR Interferometry (ALOS-2 Stripmap-ScanSAR 위상간섭기법에서의 스펙트럼 분석 평가)

  • Park, Seo-Woo;Jung, Seong-Woo;Hong, Sang-Hoon
    • Korean Journal of Remote Sensing
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    • v.36 no.2_2
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    • pp.351-363
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    • 2020
  • It is well known that alluvial sediment located in coastal region has been easily affected by geohazard like ground subsidence, marine or meteorological disasters which threaten invaluable lives and properties. The subsidence is a sinking of the ground due to underground material movement that mostly related to soil compaction by water extraction. Thus, continuous monitoring is essential to protect possible damage from the ground subsidence in the coastal region. Radar interferometric application has been widely used to estimate surface displacement from phase information of synthetic aperture radar (SAR). Thanks to advanced SAR technique like the Small BAseline Subset (SBAS), a time-series of surface displacement could be successfully calculated with a large amount of SAR observations (>20). Because the ALOS-2 PALSAR-2 L-band observations maintain higher coherence compared with other shorter wavelength like X- or C-band, it has been regarded as one of the best resources for Earth science. However, the number of ALOS-2 PALSAR-2 observations might be not enough for the SBAS application due to its global monitoring observation scenario. Unfortunately, the number of the ALOS-2 PALSAR-2 Stripmap images in area of our interest, Busan which located in the Southeastern Korea, is only 11 which is insufficient to apply the SBAS time-series analysis. Although it is common that the radar interferometry utilizes multiple SAR images collected from same acquisition mode, it has been reported that the ALOS-2 PALSAR-2 Stripmap-ScanSAR interferometric application could be possible under specific acquisition mode. In case that we can apply the Stripmap-ScanSAR interferometry with the other 18 ScanSAR observations over Busan, an enhanced time-series surface displacement with better temporal resolution could be estimated. In this study, we evaluated feasibility of the ALOS-2 PALSAR-2 Stripmap-ScanSAR interferometric application using Gamma software considering differences of chirp bandwidth and pulse repetition frequency (PRF) between two acquisition modes. In addition, we analyzed the interferograms with respect to spectral shift of radar carrier frequency and common band filtering. Even though it shows similar level of coherence regardless of spectral shift in the radar carrier frequency, we found periodic spectral noises in azimuth direction and significant degradation of coherence in azimuth direction after common band filtering. Therefore, the characteristics of spectral bandwidth in the range and azimuth direction should be considered cautiously for the ALOS-2 PALSAR-2 Stripmap-ScanSAR interferometry.

The Effect of Street Gardens on Psychological Restoration (도심 가로정원의 심리적 회복효과에 관한 연구)

  • Kwon, Hyun-Sook;Hahm, Yean-Kyoung;Kim, Hae-Ryung;Yoon, Hee-Yeun
    • Journal of the Korean Institute of Landscape Architecture
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    • v.45 no.1
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    • pp.35-51
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    • 2017
  • Street gardens, a series of streetscape improvement projects led by Seoul City Government, are initiated for the purpose of providing aesthetic satisfaction and mental refreshment to pedestrians. In order to investigate whether street gardens indeed promote the psychological health of the users, questionnaire surveys were conducted on three selected street gardens - at Gangnam-daero, Digital-ro, and Teheranro - and their comparison sites located on the same streets, which have a similar physical environment but without a street garden. The survey questionnaires, based on Attention Restoration Theory, were composed of Perceived Restorativeness Scale-11 with the eleven individual questions grouped into four categories: 'Fascination', 'Being away', 'Coherence', and 'Scope'. The survey questionnaires also ask about physical components that promote psychological improvement in the aforementioned categories. The collected data was analyzed with factor analysis, reliability analysis, and independent t-test. The results suggested that street gardens had a relatively positive effect on the psychological restorativeness of the users. In particular, they gave fascination and interest to the users. However, they did not offer a feeling of being away to the users, which revealed the limitation in the psychological improvement effect of street gardens. The physical components of the street garden that have led the psychological restorativeness effect were wooden bench, tree, and flower. This result corresponds to an extant theory that natural factors have a positive effect on the psychological restorativeness within a hardscape. This research will shed light on the planning and design guidelines for the street garden project.