• 제목/요약/키워드: Coherence Effect

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Complex Conjugate Resolved Retinal Imaging by One-micrometer Spectral Domain Optical Coherence Tomography Using an Electro-optical Phase Modulator

  • Fabritius, Tapio E.J.;Makita, Shuichi;Yamanari, Masahiro;Myllyla, Risto A.;Yasuno, Yoshiaki
    • Journal of the Optical Society of Korea
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    • v.15 no.2
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    • pp.111-117
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    • 2011
  • Full-range spectral domain optical coherence tomography (SD-OCT) with a 1-${\mu}m$ band light source is shown here. The phase of the reference beam is continuously stepped while the probing beam scans the sample laterally (B-scan). The two dimensional spectral interferogram obtained is processed by a Fourier transform method to obtain a complex spectrum leading to a full-range OCT image. A detailed mathematical explanation of the complex conjugate resolving method utilized is provided. The system's measurement speed was 7.96 kHz, the measured axial resolution was $9.6{\mu}m$ in air and the maximum sensitivity 99.4 dB. To demonstrate the effect of mirror image elimination, In vivo human eye pathology was measured.

Effectiveness Analysis on the Coherence and Time for Synthetic Aperture Sonar (코히어런스 영향과 시간에 따른 실측 데이터의 합성 효과 실험)

  • Kang Hyun-Woo
    • The Journal of the Acoustical Society of Korea
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    • v.25 no.4
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    • pp.172-177
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    • 2006
  • Various research and development on Synthetic Aperture Sonar technique is under way to enhance bearing resolution of a SONAR system. In this paper, we estimated perturbed array shapes, and compensated distortion by using estimated away shapes and synthesized arrays in aperture domain such as an ETAM technique. As experimental data, we used the one obtained from towed array in neighboring waters of the Korean peninsula. Through simulation on data where tow-ship speed is maintained at a constant level, we confirmed that synthesis effect of increasing SNR and narrowed beam width of main lobe was consistently demonstrated for about 1 minute when coherence of target signal was maintained. Also, we showed that the synthesis effect with respect to time was constantly maintained.

The Structural Relationship among Sense of Coherence, Clinical Practice Stress, and Departmental Satisfaction of Dental Hygiene Students (치위생(학)과 학생의 통합성, 임상실습스트레스, 학과만족도의 구조적 관계)

  • Jeon, Ki Ha;Lim, Soon Ryun;Kim, Mi
    • Journal of dental hygiene science
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    • v.16 no.5
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    • pp.323-330
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    • 2016
  • The purpose of this study was to understand the comprehensive relationship among sense of coherence, clinical practice stress, and major satisfaction of students in the department of dental hygiene. From four local universities, departments of dental hygiene were selected: two departments represented a three-year curriculum system and two represented a four-year curriculum system. Data from the final questionnaires of 319 students were analyzed. Differences between variables were analyzed using t-tests and ANOVAs, and correlations were checked using Pearson's correlation coefficients. Path analysis was conducted to analyze the relationship among clinical practice stress, sense of coherence, and major satisfaction. The results indicated that clinical practice stress had a negative influential relationship with both sense of coherence, and major satisfaction. In addition, sense of coherence had a positive influential relationship with major satisfaction. The direct and indirect effects among factors displayed significant differences, indicating that clinical practice stress has a partial mediation effect on sense of coherence and major satisfaction. Therefore, major satisfaction can be increased by developing and implementing programs to improve sense of coherence.

The Effect of Stress and Sense of Coherence on Health Behavior Compliance in Outpatients with Stroke (뇌졸중 환자의 스트레스와 통합성이 건강행위 이행에 미치는 영향)

  • Lee, Won Joo;Lee, Ji Won
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.1
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    • pp.232-239
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    • 2020
  • The purpose of this study was to identify the effect of stress and sense of coherence on health behavior compliance in patients with stroke. The subjects were 124 outpatients with stroke at a general hospital in Ulsan from May to July, 2019. The data were analyzed using descriptive statistics, t-test, one-way ANOVA, Scheffé test, Pearson's correlation coefficient and hierarchical multiple regression analysis by using SPSS 25.0. In the results, the health behavior compliance showed a significantly positive correlation with sense of coherence(r=.71, p<.001) and a negative correlation with stress(r=-.53, p<.001). The predictors of model 1 were gender(t=4.07, p<.001), education level(t=4.18, p<.001), and monthly income(t=-2.34, p=.021) and the statistical power was 39.6%. The predictors of model 2 were gender(t=4.65, p<.001), education level(t=43.24, p<.001), and sense of coherence(t=4.33, p<.001) and the statistical power was 60.4%. Thus, a nursing intervention program which is focused on a sense of coherence could promote health behavior compliance in patients with stroke.

Factors Influencing Health Status by the salutogenic Theory of Radiologists (방사선사의 건강생성이론에 의한 건강상태 영향요인)

  • Seo, Young-Ho;Kim, Keon-Yeop;Nam, Hang-Me;Park, Chang-Hee
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.1
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    • pp.291-299
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    • 2020
  • This study is based on the theory of salutogenesis, and investigates factors affecting the health status of radiologists who experience high stress and health problems in the rapidly changing medical environment. The study enrolled 379 radiologists working at hospitals in Daegu. A health structure model was established by applying the theory of salutogenesis. Sense of coherence had a direct effect on the health status of radiologists. Psychological stress, social support, and drinking were also influential factors, due to their mediating effect on the sense of coherence. Moreover, social support was also found to be lower when job stresses were higher. Hence, increased psychological stress resulted in lower levels of sense of coherence, social support and exercise. Taken together, results of this study indicate that effects on the sense of coherence have maximum influence on the health status of radiologists, and social support among general resistance resources is an important factor for enhancing sense of coherence. In addition to social support and health behaviors, researches involving various resources and the development of organizational strategies and health promotion intervention programs are required in future, to enable radiologists to cope with their stresses and improve health.

The effects of stress perception due to COVID-19 and category coherence on category-based inductive generalization (코로나-19로 인한 스트레스 지각과 범주 응집성이 범주기반 귀납적 일반화에 미치는 효과)

  • Lee, Guk-Hee;Doh, Eun Yeong
    • Korean Journal of Cognitive Science
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    • v.33 no.3
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    • pp.135-154
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    • 2022
  • The purpose of this study was to confirm that the property generalization to social categories with low coherence is stronger when stress due to COVID-19 is perceived as high, compared to when stress is perceived as low. To this end, this study selected categories with high coherence(nun, soldier, flight attendant) and categories with low coherence(wedding planner, interpreter, florist), and recruited 336 participants to perform a category-based inductive generalization task(inferring how many properties repeatedly observed by some category members would appear across all category members), and measured their perceived COVID-19 stress. As a result, this study showed that when the cohesion of social categories is high, the effect of property generalization is stronger than when it is low, and the effect of property generalization is stronger in those who perceive stress due to Corona 19 higher than those who perceive it as low. In addition, this study confirmed that people who perceive COVID-19 stress strongly tend to generalize strongly to properties that are repeatedly observed in the low coherence category. This study is important in that it shows that there is a cognitive mechanism that is at the root of the phenomenon that stereotypes and prejudices deepen and discriminatory behaviors increase after the outbreak of COVID-19, such as COVID-19 stress and the resulting increase in attribute generalization tendency.

A Study on the Dynamic Painterly Stroke Generation for 3D Animation (3차원 애니메이션을 위한 회화적 스트로크의 동적 관리 기법)

  • Lee, Hyo-Keun;Ryoo, Seung-Taek;Yoon, Kyung-Hyun
    • Journal of Korea Multimedia Society
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    • v.8 no.4
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    • pp.554-568
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    • 2005
  • We suggest the dynamic stroke generation algorithm that provides frame-to-frame coherence in 3D non-photorealistic animations. We use 3D particle system to eliminate the visual popping effect in the animated scene. Since we have located particles on the 3D object's surface, the coherence is maintained when the object or the camera is moving in the scene. Also, this algorithm maintains the coherence when camera is zooming in/out. However, the brush strokes on the surface also zoom in/out. This result(too large or too small brush strokes) can not represent hand-crafted brush strokes. To remove this problem, we suggest stroke generation algorithm that dynamically maintains the number of brush stroke and its size during camera zoom in/out.

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An exploratory study for an evidence of electroencephalographic changes in isolated subjects for distant mental intention

  • Kim, Dae-Keun
    • Science of Emotion and Sensibility
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    • v.17 no.4
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    • pp.51-60
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    • 2014
  • This double-blind study, as a human experiment of nonlocality, investigated the effects of senders' intention on the central nervous system of a distant human receiver and it explored the roles that motivation might have in modulating these effects. Whole brain activity was measured in the receiver whom was asked to relax in a distant room for 16 minutes; the sending person directed intention of oneness toward the receiver during repeated variable-second epochs separated by variable-second non-intention epochs. The total length of intention epochs and that of nonintention epochs were balanced. Eighteen sessions were conducted. In 9 of those sessions, the sender was the receiver's lover. In another 9 of those sessions, the sender was just acquainted with the receiver before the session. The receiver's whole brain activity recorded during the intention epochs were compared with the same measures recorded during the nonintention epochs used as controls. The statistical difference between the intentions versus controls across 18 sessions was examined by paired-t test. In addition, subgroup analysis for the 9 couple sessions and 9 non-couple sessions were additionally examined by the same test. The effect of distant intentionality decreased slow waves or increased EEG fast waves mainly in frontal regions, and increased EEG coherence during the intention epochs. The effects was not statistically significant after Bonferroni correction, but the couple sessions combined showed the largest effect followed by all sessions combined. Non-couple sessions combined showed the smallest effect. The changes in EEG power mean that receiver participants became more alert during the intention epochs and the change in EEG coherence might be evidence of coherent heart influence on EEG activity. Planned comparison with specific hypothesis testing for the suggested changes in this study have to be followed for an evidence of electroencephalographic changes in isolated subjects for the distant mental intention.

The Effect of Cohesive Devices on Memory and Understanding of Scientific Text (응집장치가 과학텍스트의 기억과 이해에 미치는 효과)

  • 김세영;한광희;조숙환
    • Korean Journal of Cognitive Science
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    • v.13 no.2
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    • pp.1-13
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    • 2002
  • This Paper is concerned with the impact of linguistic markers of coherence, such as causal connectives. repetitions. and anchoring devices. on the comprehension of a scientific text in Korean. A scientific text on the process of lightning formation was selected. and two versions of the text were constructed by varying the strength of coherence. Eighty-two undergraduate students took Part in the experiment in which they were instructed to fill in the blanks in each text in a recall and a recognition task and to respond to a set of question in a comprehension test. The results of this experiment revealed a selective effect of the cohesive markers. It was found that the different linguistic signals seem to Play a facilitating role in varying degrees in accordance with the type of tasks involved Moreover an analysis of topic continuity from the beginning paragraphs through the last revealed that the text was better understood in the paragraphs containing the main topic better than those without it. This finding seems to indicate that the off-line processing of scientific text is not influenced solely by the local bottom-up processing alone The effect of topic continuity seems to suggest that a global. top-down processing effect has an important role to play. overriding the impact of cohesive devices.

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