• Title/Summary/Keyword: S-coherence

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Coherence and Relevance Principle in Discourse Interpretation (담화 해석의 결속성 및 적합성 원리)

  • HyonHoLee
    • Korean Journal of Cognitive Science
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    • v.3 no.1
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    • pp.113-137
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    • 1991
  • Coherence and relevaned concern the ways in which discouse is interpreted.In this inversigation, the notions of coherence and relevance are discussed with examples in which they account for discourse interpretation and Charolles's(1983)procedural model of coherence is compared and combined with Sperber & Wilson's(1986a)Principle of Relevance. It is shown that the notion of coherence is not adeqiately established, but that the procedural approach will be a bridge between the prinxiples of coherence and relevance, each of which still remainas to be enriched and completed.

Mean Phase Coherence as a Supplementary Measure to Diagnose Alzheimer's Disease with Quantitative Electroencephalogram (qEEG)

  • Che, Hui-Je;Jung, Young-Jin;Lee, Seung-Hwan;Im, Chang-Hwan
    • Journal of Biomedical Engineering Research
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    • v.31 no.1
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    • pp.27-32
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    • 2010
  • Noninvasive detection of patients with probable Alzheimer's disease (AD) is of great importance for assisting a medical doctor's decision for early treatment of AD patients. In the present study, we have extracted quantitative electroencephalogram (qEEG) variables, which can be potentially used to diagnose AD, from resting eyes-closed continuous EEGs of 22 AD patients and 27 age-matched normal control (NC) subjects. We have extracted qEEG variables from mean phase coherence (MPC) and EEG coherence, evaluated for all possible combinations of electrode pairs. Preliminary trials to discriminate the two groups with the extracted qEEG variables demonstrated that the use of MPC as a supplementary or alternative measure for the EEG coherence may enhance the accuracy of noninvasive diagnosis of AD.

Sense of Coherence in Salutogenic Paradigm

  • Chung, Chae-Weon
    • Journal of Korean Academy of Nursing
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    • v.29 no.5
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    • pp.1049-1057
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    • 1999
  • The central concept of the Salutogenic Model is sense of coherence, which is defined as a global orientation that expresses the extent to which one has a feeling of confidence that one's internal and external environments are comprehensible, manageable, and meaningful. Sense of coherence is proposed as a determinant of positive health consequences and successful coping. The purpose of this article is to review Antonovsky's Salutogenic Model, the concept of sense of coherence, and its central components and sources. For conceptual clarity, sense of coherence is compared and contrasted with the concept of hardiness. The empirical research findings are integrated to better understand sense of coherence and to enhance future implications for nursing research and practice.

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Coherence Studies of Photons Emitted from a Single Terrylene Molecule Using Michelson and Young’s Interferometers

  • Yoon, Seung-Jin;Trinh, Cong Tai;Lee, Kwang-Geol
    • Journal of the Optical Society of Korea
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    • v.19 no.6
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    • pp.555-559
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    • 2015
  • Coherence length (time) is a key parameter in many classical and quantum optical applications. Two interferometers – Michelson and Young’s double-slit – are used to characterize the temporal coherence of single photons emitted from single terrylene molecules. For quantitative analysis, a dispersion-related distortion in the interference pattern of a Michelson interferometer is carefully corrected by a simple dispersion compensation. Additionally, it has been demonstrated that Young’s interferometer can be used in temporal coherence studies at the single photon level with high accuracy. The pros and cons of the two systems are discussed. The measured coherence lengths in the two systems are consistent with one another under the self-interference interpretations.

Enhanced data-driven simulation of non-stationary winds using DPOD based coherence matrix decomposition

  • Liyuan Cao;Jiahao Lu;Chunxiang Li
    • Wind and Structures
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    • v.39 no.2
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    • pp.125-140
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    • 2024
  • The simulation of non-stationary wind velocity is particularly crucial for the wind resistant design of slender structures. Recently, some data-driven simulation methods have received much attention due to their straightforwardness. However, as the number of simulation points increases, it will face efficiency issues. Under such a background, in this paper, a time-varying coherence matrix decomposition method based on Diagonal Proper Orthogonal Decomposition (DPOD) interpolation is proposed for the data-driven simulation of non-stationary wind velocity based on S-transform (ST). Its core idea is to use coherence matrix decomposition instead of the decomposition of the measured time-frequency power spectrum matrix based on ST. The decomposition result of the time-varying coherence matrix is relatively smooth, so DPOD interpolation can be introduced to accelerate its decomposition, and the DPOD interpolation technology is extended to the simulation based on measured wind velocity. The numerical experiment has shown that the reconstruction results of coherence matrix interpolation are consistent with the target values, and the interpolation calculation efficiency is higher than that of the coherence matrix time-frequency interpolation method and the coherence matrix POD interpolation method. Compared to existing data-driven simulation methods, it addresses the efficiency issue in simulations where the number of Cholesky decompositions increases with the increase of simulation points, significantly enhancing the efficiency of simulating multivariate non-stationary wind velocities. Meanwhile, the simulation data preserved the time-frequency characteristics of the measured wind velocity well.

The Effects of Action Observation with Functional Electrical Stimulation on Corticomuscular Coherence

  • Kim, Ji Young;Ryu, Young Uk;Park, Jiwon
    • The Journal of Korean Physical Therapy
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    • v.32 no.6
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    • pp.365-371
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    • 2020
  • Objective: To investigate the action observation effects of functional electrical stimulation (FES) on the communication between motor cortex and muscle through corticomuscular coherence (CMC) analysis. Methods: Electroencephalogram (EEG) and electromyogram (EMG) of 27 healthy, nonathlete subjects were measured during action observation, FES, and action observation with FES, which lasted for 7sper session for 10 times. All trials were repeated for 30 times. Simultaneously measured EEG raw data and rectified EMG signals were used to calculate CMC. Only confidence limit values above 0.0306 were used for analysis. CMC was divided into three frequency domains, andthe grand average coherence and peak coherence were computed. Repeated ANOVA was performed to analyze the coherence value difference for each condition's frequency band. Results: CMC showed significant differences in peak coherence and average coherence between the conditions (p<0.05). Action observation application with FES in all frequency band showed the highest peak and average coherence value. Conclusions: The results of this study are assumed to be the combination of increased eccentric information transfer from the sensorymotor cortex by action observation and an increased in concentric sensory input from the peripheral by the FES, suggesting that these are reflecting the sensorimotor integration process.

Interferometric coherence analysis using space-borne synthetic aperture radar with respect to spatial resolution (공간해상도에 따른 위성 영상레이더 위상간섭기법 긴밀도 분석)

  • Hong, Sang-Hoon;Wdowinski, Shimon
    • Korean Journal of Remote Sensing
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    • v.29 no.4
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    • pp.389-397
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    • 2013
  • Recently high spatial resolution space-borne Synthetic Aperture Radar (SAR) systems have launched and have been operated successfully. Interferometric SAR (InSAR) processing with the space-based high resolution observations acquired by these systems can provide more detail information for various geodetic applications. Coherence is regarded as a critical parameter in the evaluating the quality of an InSAR pair. In this study, we evaluate the coherence characteristics of high-resolution data acquired by TerraSAR-X (X-band) and ALOS PALSAR (L-band) and intermediate-resolution data acquired by Envisat ASAR (C-band) over western Texas, U.S.A. Our coherence analysis reveals that the high-resolution X-band TSX (3.1 cm) data has a high coherence level (0.3-0.6), similar to that of the L-band ALOS PALSAR data (23.5 cm) in short temporal baselines. Further more, the TSX coherence values are significantly higher than those of the C-band (5.6 cm) Envisat ASAR data. The higher coherence of the TSX dataset is a surprising result, because common scattering theories suggest that the longer wavelength SAR data maintain better coherence. In vegetated areas the shorter wavelength radar pulse interacts mostly with upper sections of the vegetation and, hence, does not provide good correlation over time in InSAR pairs. Thus, we suggest that the higher coherence values of the TSX data reflect the data's high-resolution, in which stable and coherent scatters are better maintained. Although, however, the TSX data show a very good coherence with short temporal baseline (11-33 days), the coherences are significantly degraded as the temporal baselines are increased. This result confirms previous studies showing that the coherence has a strong dependency on the temporal baseline.

A Statistical Analysis of JERS L-band SAR Backscatter and Coherence Data for Forest Type Discrimination

  • Zhu Cheng;Myeong Soo-Jeong
    • Korean Journal of Remote Sensing
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    • v.22 no.1
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    • pp.25-40
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    • 2006
  • Synthetic aperture radar (SAR) from satellites provides the opportunity to regularly incorporate microwave information into forest classification. Radar backscatter can improve classification accuracy, and SAR interferometry could provide improved thematic information through the use of coherence. This research examined the potential of using multi-temporal JERS-l SAR (L band) backscatter information and interferometry in distinguishing forest classes of mountainous areas in the Northeastern U.S. for future forest mapping and monitoring. Raw image data from a pair of images were processed to produce coherence and backscatter data. To improve the geometric characteristics of both the coherence and the backscatter images, this study used the interferometric techniques. It was necessary to radiometrically correct radar backscatter to account for the effect of topography. This study developed a simplified method of radiometric correction for SAR imagery over the hilly terrain, and compared the forest-type discriminatory powers of the radar backscatter, the multi-temporal backscatter, the coherence, and the backscatter combined with the coherence. Statistical analysis showed that the method of radiometric correction has a substantial potential in separating forest types, and the coherence produced from an interferometric pair of images also showed a potential for distinguishing forest classes even though heavily forested conditions and long time separation of the images had limitations in the ability to get a high quality coherence. The method of combining the backscatter images from two different dates and the coherence in a multivariate approach in identifying forest types showed some potential. However, multi-temporal analysis of the backscatter was inconclusive because leaves were not the primary scatterers of a forest canopy at the L-band wavelengths. Further research in forest classification is suggested using diverse band width SAR imagery and fusing with other imagery source.

Correlation sense of coherence and quality of life among freshman nursing students (간호대학 신입생의 통합성과 삶의 질 관계)

  • Park, Hye-Seo;Hwang, Kyung-Hye;Cho, Ok-Hee
    • Journal of Home Health Care Nursing
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    • v.22 no.1
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    • pp.5-13
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    • 2015
  • Purpose: The purpose of this study was to identify the relationship between sense of coherence and quality of life in the freshman nursing students. Method: The subjects of this study were 377 freshmen of nursing colleges. Data were collected through structured questionnaires of sense of coherence and quality of life. Data analysis was done using descriptive statistics, t-test, ANOVA, Pearson's correlation coefficient and canonical correlation analysis. Result: There was static correlation between sense of coherence and quality of life in the freshman nursing students. And high correlation with quality of life were meaningfulness in sense of coherence and psychological domain in quality of life. Conclusion: These results were shown very important to improve meaningfulness in sense of coherence and psychological domain in quality of life to raise the quality of life in the freshman nursing students. Therefore, in order to improve the quality of life, it is necessary to develop a nursing intervention program that focus on stress, and psychological health.

Multiple Linear Chirp Based Transmission Scheme for IEEE 802.15.4a Chirp Spread Spectrum (IEEE 802.15.4a CSS를 위한다중 선형 Chirp 전송 기법)

  • Kim, Kwang-yul;Lee, Seung-woo;Kim, Yong-sin;Lee, Jae-seang;Kim, Jin-young;Shin, Yoan
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.40 no.10
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    • pp.1937-1939
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    • 2015
  • In order to improve the performance of a chirp based transmission scheme, the cross-coherence property should be carefully considered. In this paper, we propose two pairs of combinations using multiple linear chirp (MLC) which can reduce the cross-coherence for improving IEEE 802.15.4a chirp spread spectrum systems. The simulation results show that the proposed MLC scheme can improve the performance by considering the cross-coherence.