• Research in Community and Public Health Nursing
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• v.31 no.3
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• pp.269-278
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• 2020

Purpose: The study was conducted to identify the relationship between subjective family class and suicidal ideation and to determine the double mediating effect of social support and sense of coherence on their relationship. Methods: Secondary analysis of data from 2015 Korean Psycho-social Anxiety which was a population-based representative was performed. Double mediating effects of social support and sense of coherence on suicidal ideation were analyzed using the PROCESS macro (model 6) with bootstrapping methods. Results: Subjective family class directly influenced social support (β=.20, p<.001) and sense of coherence (β=.10, p<.001). Subjective family class directly influenced suicide ideation (β=-.08, p<.001). Sense of coherence was directly influenced by social support (β=.28, p<.001). Suicide ideation was indirectly influenced by subjective family class through social support (β=-.22, p<.001) and sense of coherence (β=-.36, p=.001). The size of direct effect of subjective family class on suicide ideation was 0.24 and the total size of indirect effect was 0.12. Conclusion: Intervention to improve social support and sense of coherence is needed to prevent the suicide among adolescents.

• Wind and Structures
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• v.30 no.2
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• pp.181-198
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• 2020

In the traditional buffeting response analysis method, the spanwise incomplete correlation of buffeting forces is always assumed to be same as that of the incident wind turbulence and the action of the signature turbulence is ignored. In this paper, three typical bridge decks usually adopted in the real bridge engineering, a single flat box deck, a central slotted box deck and a two-separated paralleled box deck, were employed as the investigated objects. The wind induced pressure on these bridge decks were measured via a series of wind tunnel pressure tests of the sectional models. The influences of the wind speed in the tests, the angle of attack, the turbulence intensity and the characteristic distance were taken into account and discussed. The spanwise root coherence of buffeting forces was also compared with that of the incidence turbulence. The signature turbulence effect on the spanwise root coherence function was decomposed and explained by a new empirical method with a double-variable model. Finally, the formula of a sum of rational fractions that accounted for the signature turbulence effect was proposed in order to fit the results of the spanwise root coherence function. The results show that, the spanwise root coherence of the drag force agrees with that of incidence turbulence in some range of the reduced frequency but disagree in the mostly reduced frequency. The spanwise root coherence of the lift force and the torsional moment is much larger than that of the incidence turbulence. The influences of the wind speed and the angle of attack are slight, and they can be ignored in the wind tunnel test. The spanwise coherence function often involves several narrow peaks due to the signature turbulence effect in the high reduced frequency zone. The spanwise coherence function is related to the spanwise separation distance and the spanwise integral length scales, and the signature turbulence effect is related to the deck-width-related reduced frequency.

• Journal of Korean Biological Nursing Science
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• v.17 no.1
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• pp.50-59
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• 2015

Purpose: The purpose of this study was to determine the relationship among concepts of the salutogenic model - sense of coherence, occupational stress, and health status in clinical nurses. Methods: Participants were recruited from a hospital in Seoul using a stratified random sampling. A total of 349 nurses participated in the study and data were collected using a self-administered questionnaire. The structural equation model was used to assess the relationships among the variables. Results: The results of the study showed that occupational stress and health behavior were significant factors, directly explaining the health status of nurses. Factors explaining occupational stress were: sense of coherence, and social support. Sense of coherence showed higher effects on occupational stress than those of social support. Sense of coherence and the work conditions (work experience and shift work) of nurses had a significant and direct effect on health behavior. Sense of coherence and social support had a significant and indirect effect on health status through occupational stress and health behavior. Conclusion: Strategies to enhance sense of coherence and social support are necessary for successful health promotion programs for nurses.

• Journal of information and communication convergence engineering
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• v.12 no.4
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• pp.221-227
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• 2014

In this paper, we analyze the effect of the coherence bandwidth of wireless channels on leakage suppression methods for discrete Fourier transform (DFT)-based channel estimation in orthogonal frequency division multiplexing (OFDM) systems. Virtual carriers in an OFDM symbol cause orthogonality loss in DFT-based channel estimation, which is referred to as the leakage problem. In order to solve the leakage problem, optimal and suboptimal methods have already been proposed. However, according to our analysis, the performance of these methods highly depends on the coherence bandwidth of wireless channels. If some of the estimated channel frequency responses are placed outside the coherence bandwidth, a channel estimation error occurs and the entire performance worsens in spite of a high signal-to-noise ratio.

• Korean Journal of Cognitive Science
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• v.31 no.3
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• pp.77-102
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• 2020

Some progress has been made in the study of the category coherence effect, which states that the attributes of soldiers or nuns with similarities in dress and behavior, and easily distinguished from other categories, are likely to be generalized. However, few studies have examined the fundamental psychological mechanisms that underlie this category coherence effect, and this study aims to fill this gap. For this purpose, two experiments were conducted after selecting categories with high coherence (nuns, soldiers, and flight attendants) and those with low coherence (interpreters, wedding planners, and florists). In experiment 1, we observed that the members of a category were presumed to have certain reasons to prefer [property X] (presumption of reasons for preference), with this presumption becoming stronger when [property X] was observed repeatedly in high-coherence categories than in the case of low-coherence categories. Experiment 2 showed that for the high-coherence categories, the presumption of reasons for preference was stronger when [property X], rarely seen in everyday life (base rate of 30%), was observed, while the presumption of reasons for preference was weaker when [property Y] (base rate 70%), frequently seen in everyday life, was observed. In the low-coherence categories, the presumption of reasons for preference tended to be weak for both rare and frequent attributes. That is, there were significant effects of the two-way interaction between category coherence and base rate on the presumption of reasons for preference. This study has implications for psychological essentialism and stereotyping.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.11a
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• pp.298-303
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• 2003

The eccentric rotor system has various problems by vibration of unbalance mass. Specially, it is difficult to analyze vibration problem for the drum washing machine due to correlation of transmission paths. We analyze the mechanical structure by multidimensional spectral density to identify the maximum vibration magnitude at the frequency domain. It estimates the coherence function of the signals to pass the transmission paths. In case of the drum washing machine, because the transmission paths are correlated partially it needs to determinate the priority ranking. And the correlated parts are eliminated using conditioned spectral density function. Finally the shielding effect method confirms the reasonability of the modeling.

• Proceedings of the Korean Information Science Society Conference
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• 2012.06c
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• pp.406-407
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• 2012

Texture transfer is a NPR technique for expressing various styles according to source (reference) image. By late 2000s, there are many texture transfer researches. But video base researchers are not active. Moreover, they didn't use important feature like directional information which need to express detail characteristics of target. So, we propose a new method to generate texture transfer animation (using video) with directional effect for maintaining temporal coherence and controlling coherence direction of texture. For maintaining temporal coherence, we use optical flow and confidence map to adapt for occlusion/disocclusion boundaries. And we control direction of texture for taking structure of input. For expressing various texture effects according to different regions, we calculate gradient based on directional weight. With these techniques, our algorithm can make animation result that maintain temporal coherence and express directional texture effect. It is reflect the characteristics of source and target image well. And our result can express various texture directions automatically.

• 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.

• Korean Journal of Optics and Photonics
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• v.2 no.1
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• pp.36-49
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• 1991

The coherence properties of electromagnetic fields are reviewed, based on both the classical and quantum theories. The elementary concepts, employed frequently in the discussion of interference phenomena, are summarized. The well-known interference phenomena are described in terms of second-order coherences. The coherence theory in space-frequency domain is introduced and the coherent mode representation is presented. The generation and propagation of coherence of light are analysed and it is shown that the coherence of light is developed as light propagates. The quantum theory goes parallel with the classical theory, via the optical equivalence theorem. There are, however, certain nonclassical characteristics of light, which may not be easily understood in classical therms. These nonclassical phenomena are believed to originate from the particle aspects of light. The quantum effect on the interfernce phenomena is analysed and finally the outlook of the future research is briefly mentioned.

• 한국초전도학회:학술대회논문집
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• v.14
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• pp.48-48
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• 2004