• Journal of the Korean Society of Radiology
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• v.12 no.4
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• pp.541-547
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• 2018

To evaluate the effect of dose and image quality for Chest Digital Tomosynthesis(CDT) using sensitivity and tube voltage(kV). CDT images of the phantom were acquired varying sensitivity 200, 320, 400 according to set tube voltage of 125 kV and 135 kV. The dose and Dose Area Product(DAP) according to change of sensitivity and kV were evaluated and Image quality was evaluated by PSNR, CNR, SNR using Image J. Dose were lowered 14~23% less than sensitivity 200, 125 kV and DAP were lowered 13~26% less than sensitivity 200, 125 kV. PSNR were over 27 dB, which were significant value and CNR, SNR were better as sensitivity value was lower. But there were different statistical significant to each item. CNR and SNR were not statistically significant at sensitivity 320, 135 kV(P>0.05). CDT can improve image quality with lower radiation dose using better than quality and correction power at digital radiography system.

• Journal of Ginseng Research
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• v.45 no.6
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• pp.676-682
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• 2021

Background: Red ginseng has been found to improve ocular perfusion and dry eye syndrome in glaucomatous eyes; however, its effects on visual function and vision-related quality of life have not been investigated. This study sought to evaluate the effects of red ginseng on visual function and vision-related quality of life in glaucoma patients using contrast sensitivity and a questionnaire. Methods: Participants were randomly assigned to two groups in this prospective, randomized, double-blind study: in one group, red ginseng was taken first, followed by a placebo, and in the other, placebo was taken first, followed by red ginseng. We measured and compared changes in contrast sensitivity and vision-related quality of life between the two groups. Contrast sensitivity was measured using OPTEC® 6500P, and vision-related quality of life was evaluated using the 25-item National Eye Institute Visual Function Questionnaire. One-way and two-way repeated measure analyses of variance were used for the comparison. Relationships between respective changes in dry eye syndrome and contrast sensitivity were also analyzed. Results: Daytime contrast sensitivity and ocular pain improved after the administration of red ginseng. Nighttime contrast sensitivity was improved in early or moderate glaucoma. Improved contrast sensitivity was not associated with improvement in dry eye syndrome. Conclusion: Red ginseng could improve contrast sensitivity and ocular pain in patients with glaucoma. The mechanism underlying improvement in contrast sensitivity appears to be associated with enhanced retinal perfusion or retinal ganglion cell function, but not dry eye syndrome.

• Journal of the Korean Society of Costume
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• v.66 no.2
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• pp.1-14
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• 2016

This study was intended to investigate the influences that consumer's price sensitivity, bundle discount type, and price level of the male cosmetics have on consumer attitude. The design of this research was comprised of $2{\times}2{\times}2$ mixed design studies. The first element was high price sensitivity vs. low sensitivity, the second element was the bundle discount type (mixed leader vs. mixed-joint), and the third element was the price level of male cosmetics (high-price brand vs. low-price brand). The results of this study showed that price sensitivity, bundle discount type and price level of male cosmetic had a statistically significant interaction effect on the consumer's quality perception. The quality perception of low-cost brands for high price sensitivity/mixed-joint bundle group was low. The quality perception of low-cost brands for mixed-leader bundled groups did not change significantly even when the price sensitivity became higher. However, it can be seen as the same result that the overall value is higher when suggested the price information in Mixed-leader bundle than Mixed-joint bundle. In particular, this study suggests that price information should be presented in mixed-leader bundles for high price sensitivity and low cast brands.

• Journal of Broadcast Engineering
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• v.19 no.4
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• pp.468-477
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• 2014

This paper proposes a novel perceptual quality-based (PQ-based) video coding method with foveated contrast sensitivity (FCS). Conventional methods on PQ-based video coding with FCS achieve minimum loss on perceptual quality of compressed video by exploiting the property of human visual system (HVS), that is, its sensitivity differs by the spatial frequency of visual stimuli. On the other hand, PQ-based video coding with foveated masking (FM) exploits the difference of the sensitivity of the HVS between the central vision and the peripheral vision. In this study, a novel FCS model is proposed which considers both the conventional DCT-based JND model and the FM model. Psychological study is conducted to construct the proposed FCS model, and the proposed model is applied to PQ-based video coding algorithm implemented on HM10.0 reference software. Experimental results show that the proposed method decreases bitrate by the average of 10% without loss on the perceptual quality.

• Journal of Industrial Technology
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• v.18
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• pp.233-240
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• 1998

In this study, ride sensitivity analysis of train with non-linear suspension elements is performed. Non-linear characteristics of springs and dampers for primary and secondary suspensions of a train is parameterized. Equation of motion of the train model is derived, and using the direct differentiation method, sensitivity equations are obtained. For a nominal ride quality performance index, sensitivity analysis with respect to various design parameters regarding non-linear suspension parameters is carried out.

• Water for future
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• v.21 no.4
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• pp.407-414
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• 1988

The purpose of this paper is to study the following ; (1) how the stability and sensitivity of a given stream water quality model can be analyzed theoretically by means of the stability theory and the sensitivity theory, and (2) point out that the results of this study prove that numerical analysis for the given stream water quality model is reliable, and the model is sensitive for the variations of parameters. A stability theory which is described by the infinite Fourier series is used to analyze the numerical scheme of the model. The numerical shheme is used a backward implicit scheme. a sensitivity theory which is described by the first order linear vector equation is used to analyze theoretically the effect of variations of water quality parameters such as BOD loads, flow rate, temperature. The results of sensitivity theory are of general applicability and are presented in a analytical form. The results of this study seems to be satisfactory for the reliability of stream water quality model with respect to the numerical scheme and the variations of the water quality parameters.

• Anxiety and mood
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• v.9 no.1
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• pp.25-30
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• 2013

Objective : Panic disorder is a chroni, debilitating illness, and has been known to be affected by high anxiety sensitivity and a poor quality of life. We examined if 12 weeks of pharmacotherapy with escitalopram could affect anxiety sensitivity, quality of life, and general disability in patients with panic disorder. Method : We enrolled 27 patients who met the DSM-IV-TR criteria for panic disorder, with or without agoraphobia, and completed 12 weeks of escitalopram treatment. We enrolled 29 normal control subjects who were matched for age and sex compared with the panic patients. All subjects were assessed using the Hamilton Rating Scale for depression (HAM-D), Hamilton Rating Scale for Anxiety (HAM-A), Panic Disorder Severity Scale (PDSS), Anxiety Sensitivity Index-Revised (ASI-R), WHO quality of life assessment (WHO-QOL) and Sheehan Disability Scale (SDS) before and after 12 weeks of treatment. Result : Panic disorder patients had a higher Anxiety sensitivity, a poorer Quality of life, and significant disability than normal control subjects at baseline. After the treatment, Panic disorder patients showed significant improvement in the severity of panic symptoms in terms of the HAM-A p<0.001), HAM-D (p<0.001) in addition, the reached a remission state in terms of the PDSS score. They also showed significant improvement in the ASI-R (p<0.001), WHO-QOL (p<0.001) and SDS (p<0.001), but mean scores of the ASI-R, WHO-QOL and SDS in panic disorder patients were did not reach normal levels. Conclusion : This study suggests that 12 weeks of pharmacotherapy with escitalopram could improve anxiety sensitivity, quality of life, and disability in panic disorder patients, although their anxiety sensitivity, quality of life and disability were not yet normalized after short-term pharmacotherapy. Thus, long-term pharmacotherapy may be necessary for panic disorder patients in order to get an optimal clinical response in terms of anxiety sensitivity, quality of life, and general disability.

• Journal of the Korea Society of Computer and Information
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• v.24 no.6
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• pp.81-88
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• 2019

Based on the theory of planned behavior and the theory of legal deterrence, this study takes consumers' willingness to pay for digital music as the research object, investigates the consumers who have digital music consumption channels and behaviors, and discusses the willingness of consumers to pay for digital music and its influencing factors. The study attempts to achieve the following research purposes: First, explore the influencing factors of willingness to pay for digital music using domestic and foreign literature research and related content analysis. Second, we want to examine the effect of Attitude, Collective Specifications, Quality Sensitivity and Music affinity on willingness to pay. Third, Legal deterrence and resource availability tries to verify whether there is a moderating effect between Attitude, Collective Specifications, Quality Sensitivity and Music affinity and willingness to pay. The research data was collected in 2019 between April 6th to May 8th. Questionnaires were randomly distributed in fixed places, mainly in Hubei Province, China. A total of 393 questionnaires were selected for data analysis. Based on the previous theoretical review and empirical analysis, the study draws the following conclusions: Firstly, attitude, collective specifications, quality sensitivity and music affinity have an impact on the willingness to pay. Second, Legal deterrence has a regulatory effect on the relationship among quality sensitivity, musical affinity and the willingness to pay. Last the resource availability has a significant impact on the willingness to pay. It also has a regulatory effect on the relationship among quality sensitivity, music affinity and the willingness to pay.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.2250-2255
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• 2011

There has been a growing interest toward railroad conjunction with opening of high-speed rail in 2004 and concurrent implementation of nation's green growth policies. Meanwhile, users' expectation on service of public transportation, especially railroad has been growing than since ever due to heightened quality of life, entering aging society, voice of equity for minorities, and greater interest in environments of communities. In order to come up with the expectations, actual improvements for user's convenience/comfort and its assessment strategies in terms of service quality level are necessary. This study defines the index of this aspect of service level as 'Sensitivity Quality'. This is conceived as one of the important factors to define travel cost as do the travel time and fare, but hardly taken into consideration when assessing a transportation system or policy-making for a transportation project. The elements included for the assessment of the sensitivity quality in this study are feeling of a ride, conformability and convenience what users feel and recognize using a train. This paper suggests that establishing sensitivity quality elements would contribute in foundation of assessing service quality and provide improved public transportation services through their scientific and objective development and management.

• Journal of Korean Society for Quality Management
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• v.25 no.2
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• pp.140-153
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• 1997

As product quality is maily determined in the product design and process design step, systematic design should be performed through parameter design and tolerance design. Therefore, we introduced analysis of variance and regression analysis as a statistical method which determine optimal levels of affective design factors to product characteristics, then we compared that process and result. In analysis of variance, variation of quality characteristics arises from noise factors, so the optimal levels of design factors are selected to minimize the effect of noise factors. In regression analysis, variation of quality characteristics aries from variation of each own design factors. As a method to reduce variation of these quality characteristics, sensitivity analysis was performed about each design factors. Through this sensitivity analysis, we represented process to calculate the interaction term of the factors.