• Journal of Sensor Science and Technology
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• v.27 no.4
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• pp.269-274
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• 2018

High-sensitivity signal-to-noise ratio (SNR) microphones are essentially required for a broad range of automatic speech recognition applications. Piezoelectric microphones have several advantages compared to conventional capacitor microphones including high stiffness and high SNR. In this study, we designed a new piezoelectric membrane structure by using the finite elements method (FEM) and an optimization technique to improve the sensitivity of the transducer, which has a high-quality AlN piezoelectric thin film. The simulation demonstrated that the sensitivity critically depends on the inner radius of the top electrode, the outer radius of the membrane, and the thickness of the piezoelectric film in the microphone. The optimized piezoelectric transducer structure showed a much higher sensitivity than that of the conventional piezoelectric transducer structure. This study provides a visible path to realize micro-scale high-sensitivity piezoelectric microphones that have a simple manufacturing process, wide range of frequency and low DC bias voltage.

• Korea-Australia Rheology Journal
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• v.14 no.2
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• pp.57-62
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• 2002

The sensitivity of the final filament to the ongoing sinusoidal disturbances has been Investigated in the viscoelastic spinning using frequency response method. Amplification ratios or gains of the spinline cross-sectional area at the take-up to any disturbances show resonant peaks along the frequency regime, where the frequencies at theme points directly correspond to the imaginary parts of the successive leading eigenvalues from the linear stability analysis. As shown in Jung et al. (1999) and Lee et al (2001), the sensitivity results on the effect of various process conditions such as spinline cooling and fluid viscoelasticity, obtained by dynamic transient simulation have been corroborated in this study. That is, increasing spinline cooling makes the system less sensitive to disturbances, thus stabilizes the spinning. Also, an increasing viscoelasticity for extension-thickening fluids decreases the sensitivity of the spinning. i.e., stabilizing the system, where, as it increases the sensitivity of the spinning of extension-thinning fluids. Furthermore, it has been found in the present study that the inertia force as one of secondary forces causes the system to be more stabile or less sensitive to process disturbances.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.8 s.185
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• pp.54-63
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• 2006

Enhancement methods of sensitivity to in-plane strain measurement by micro-ESPI(Electronic Speckle Pattern Interferometry) technique were proposed using TiN and Au thin films. Micro-tensile strain over the micro-tensile specimens, prepared in micro-scale by those films, was measured by micro-tensile loading system and micro-ESPI system developed in this study. The subsequent measurement of in-plane tensile strain in the micro-sized specimens was introduced using the micro-ESPI technique, and the micro-tensile stress-strain curves for these films were determined. To enhance the sensitivity to measurement of in-plane tensile strain, algorithms of the phase estimation by using curve fitting of inter-fringe and the discrete Fourier Transform with object-induced dynamic phase shifting were developed. Using these two algorithms, the micro-tensile strain-stress curves were generated. It is shown that the algorithms for enhancement of the sensitivity suggested in this study make the sensitivity to measurement of the in-plane tensile strain increase.

• The Korean Journal of Food And Nutrition
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• v.18 no.4
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• pp.385-394
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• 2005

The objective of this study is to stimulate the satisfaction on food color sensitivity through objectifying the color sensitivities on customer's foods. The preference analysis on food sensitivity adjectives is measured on 5-point scale by preferring degree on each adjectives. And it is calculated on the sensitivities for the SD method that is used for finding whether it is strong or not on food image stimulus which was photographed on the 8 restaurants in Seoul. We found the outcome as follows. The most preferred sensitivity adjective is 'cleanness', and the worst preferred one is 'unshapliness'. It is differed on genders by $95\%$ confidence interval. The attractiveness, simplicity, richness, comfort and elegance are derived from the result of factor analysis for food color sensitivity. The yellow or orange color foods are main one for the simplicity and comfort. The orange color food are fit on richness and elegance factor, and it will be most effective if choosing the color more similar to brown one.

• Safety and Health at Work
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• v.9 no.4
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• pp.473-478
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• 2018

Background: Multiple Chemical Sensitivity (MCS) is an acquired disease which etiology remains unknown. It is characterized by the development of sensitivity to certain chemical products. Most of the hypotheses formulated to explain the syndrome associate it to a previous exposition to some kind of volatile chemical. University researchers in chemical laboratories suffer a phenomenon of multi-exposition to chemical agents at low concentration during long periods of time although in an irregular form. Many of these chemical agents have similar properties to those suspicious of causing MCS. This article studies the prevalence of MCS in laboratory researchers. Methods: The study group is university researchers in chemical laboratories. The control group was obtained from administrative personnel who work in the same universities and therefore, are not exposed to chemical products from the laboratories, but have the same exposition to the rest of environmental polluting agents from the area and from the buildings of the university. In this study, it is used the Quick Environmental Exposure and Sensitivity Inventory (QEESI) (sensitivity of 92%/specificity of 95%). Results: The results showed that the prevalence of MCS for the university researchers is not related to exposition by inhalation to multiple chemical agents, at low concentration. Conclusions: The results disagree with one of the main etiological hypotheses of MCS, which is based on the existence of hypersensitive people, who presents a response after prolonged expositions to very low concentrations during a long period of time.

• Korean Journal of Childcare and Education
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• v.16 no.6
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• pp.233-252
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• 2020

Objective: The purpose of this study is to verify the effect of childcare teachers' positive human relationships in childcare centers on care sensitivity to children through their work immersion. Methods: The subjects of this study were child care teachers who were conveniently sampled from Incheon City. A total of 380 surveys were distributed, and a total of 334 surveys were analyzed, Poor or incomplete questionnaires collected were excluded. The. Sobel Test and Baron & Kenny's multi-regression were used for the analysis with the SPSS 23.0 program. Results: Child care teachers' positive relationships with directors, with their fellow teachers, and with parents had an influence on teachers' care sensitivity to children. Teacher's positive relationships with their fellow teachers and with parents had an influence on teachers' work immersion, which mediated the relationships between teacher's human relationship and their care sensitivity to children. Conclusion/Implications: The positive relationships of child care teachers directly and indirectly affect their sensitivity to children through teachers' work immersion.

• Human Ecology Research
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• v.62 no.1
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• pp.165-179
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• 2024

This study examined the effects of perceived discrimination on multicultural adolescents regarding feelings of This study examined the direct effect of socially prescribed perfectionism on interpersonal anxiety in upper elementary school students and the sequential mediating effect of dichotomous thinking and rejection sensitivity on this relationship. The sample comprised 306 upper elementary school students (grades 4 to 6; 149 boys, 48.7%) in Seoul, Incheon, and Busan. The Data were collected through an online self-report questionnaire completed by the participants and analyzed using SPSS version 27.0 and MPlus version 8.7 software. The analyses revealed three key findings. First the direct effect of socially prescribed perfectionism on interpersonal anxiety was not statistically significant. Second dichotomous thinking mediated the relationship between socially prescribed perfectionism and interpersonal anxiety, whereas rejection sensitivity did not. Finally, socially prescribed perfectionism influenced interpersonal anxiety through the sequential mediation of dichotomous thinking and rejection sensitivity. In conclusion, although socially prescribed perfectionism does not directly influence interpersonal anxiety, children may experience interpersonal anxiety in situations involving dichotomous thinking due to socially prescribed perfectionism, leading to rejection sensitivity. These findings suggest that interventions for interpersonal anxiety in upper elementary school students should focus on psychological problems attributed to socially prescribed perfectionism.

• Proceedings of the Acoustical Society of Korea Conference
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• 1985.10a
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• pp.27-30
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• 1985

• Journal of the Society of Naval Architects of Korea
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• v.49 no.1
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• pp.60-67
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• 2012

This study considers the numerical analysis on parametric roll for container ships. As a method of numerical simulation, an impulse-response-function approach is applied in time domain. A systematic study is carried out for the parametric roll of two container ships, particularly observing the sensitivity of computational results to some parameters which can affect the analysis of parametric roll. The parameters to be considered are metacentric height (GM), simulation time window, and the discretization of wave spectrum. Based on the result of parametric roll simulation, numerical sensitivity and uncertainty in computational analysis are discussed.

• English Language & Literature Teaching
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• v.18 no.2
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• pp.1-20
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• 2012

This study aims to propose using English reading strategies to enhance Intercultural Communicative Competence (ICC) for EFL learners. The study recruited college-level participants who were enrolled in a general English reading course (N=30) and administrated the surveys with a Repeated Measures Design (RMD). In the survey, an intercultural sensitivity scale and metacognitive reading strategies inventory were conducted for comparison. During the instruction, participants were asked to use the R.I.D.E.R. (i.e. Read, Image, Describe, Evaluate, and Repeat) strategy for visualization of text, which is aimed at facilitating the use of metacognitive reading strategies. In the results, participants showed a statistically significant increase both in the intercultural sensitivity level and the use of metacognitive reading strategies after the practice of R.I.D.E.R for one semester. Further analysis was appended to the results by the correlation and regression analysis, and proposed that participants benefit their development of intercultural sensitivity from the use of metacognitive reading strategies. Therefore, the study suggests that implementing metacognitive reading strategies facilitates college EFL readers to increase their cultural sensitivity, which empowers ICC through English reading (176words).