• Journal of Broadcast Engineering
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• v.17 no.1
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• pp.1-16
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• 2012

In order to improve the workflow of 3D video production, this paper analyzes the visual fatigue caused from distortions in 3D video production stage through a set of subjective visual assessment tests. To establish a set of objective indicators for subjective visual tests, various distortions in production stage are investigated to be categorized into 7 representative visual-fatigue-producing factors, and to conduct visual assessment tests for each selected category, 4 test video clips are produced by combining the extent of camera movement as well as the object(s) movement in the scene. Each produced test video is distorted to reflect each of the selected 7 visual-fatigue-producing factors, and we set 7 levels of distortion for each factor, resulting in 196 5-second-long video clips for testing. Based on these test materials and the recommendation of ITU-R BT.1438, subjective visual assessment tests are conducted by 101 applicants. The test results provide a relative importance and the tolerance limit of each visual-fatigue-producing factor, which corresponds to various distortions in 3D video production field.

• Journal of Korean Academy of Oral Health
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• v.42 no.4
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• pp.216-223
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• 2018

Objectives: The purpose of the study was to investigate factors affecting the assessment of objective and subjective masticatory ability in the elderly, and to evaluate masticatory ability assessment more accurately. Methods: A total of 112 participants were recruited after oral examination in senior citizen welfare facilities. The participants' masticatory ability was evaluated objectively (Mixing ability index; MAI), and subjectively (Key food intake ability; KFIA). Participants' general characteristics and oral health-related variables were also recorded. Based on masticatory ability assessment, participants were classified as either high or low. IBM SPSS Statistics Ver.23.0 was used for all analyses, including descriptive statistics, Chi-square test, Mann-Whitney U test, Spearman rank correlation, and Logistic regression analysis. Results: Higher masticatory ability was positively correlated with higher scores on MAI and KFIA. Additionally, there was a significant positive correlation between MAI and KFIA. When analyzing factors affecting objective and subjective masticatory ability assessments, Functional tooth units (FTUs) were revealed as a related factor. In subjective masticatory ability assessment, oral moisture, difficulty in chewing, and the Geriatric Oral Health Assessment Index (GOHAI) were also influential factors. Conclusions: In order to accurately assess masticatory ability, it is necessary to use both objective and subjective measures. Additionally, to improve the masticatory ability in the elderly, treatment should be provided to improve overall oral health and satisfaction.

• The Korean Journal of Pain
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• v.1 no.2
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• pp.137-144
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• 1988

The assessment of pain, an essentially subjective experience is an elusive and complex undertaking but is one of main problems as well as treatment in pain medicine. It is important to measure quality and quantity of pain for accurate diagnosis and establishing the treatment program and evaluating treatment outcome. Author review several measures of assessment of pain and suggest some elements for ideal form of korean pain scale.

• Journal of Broadcast Engineering
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• v.14 no.4
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• pp.387-396
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• 2009

No-Reference video-quality assessments are divided into two kinds of metrics based on decoding pixel domain or the bitstream one. Traditional full-/reduced- reference methods have difficulty to be deployed as realtime video transmission because it has problems of additional data, complexity, and assessment accuracy. This paper presents simple and highly accurate no-reference video-quality assessment in realtime video transmission. Our proposed method uses quantization parameter, motion vector, and information of transmission error. To evaluate performance of the proposed algorithm, we perform subjective test of video quality with the ITU-T P.910 Absolute Category Rating(ACR) method and compare our proposed algorithm with the subjective quality assessment method. Experimental results show the proposed quality metric has a high correlation (85%) in terms of subjective quality assessment.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.30B no.10
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• pp.42-49
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• 1993

In this paper, we evaluate the quality of synthesized speech by rule using the LPC CD as a objective measure, and then compare the test result with the subjective one. Speech used for the test consists of 108 words which are selected by word construction method using Korean attribute and frequency distribution, synthesized by demi-syllable rule. By evaluating the quality of synthesized speech by reule objectively, we have tried to resolve the problems such as lots of evaluation time, expansion of test scale, and variables of analysis result arised by subjective measure. We have, also, proved the validity of the objective test using the LPC CD, by comparing intelligibility which is the index for the subjective quality evaluation of synthesized speech by rule with MOS. From this results, we can provide a guide for quality assessment that would be useful in the R&D of synthesis method and the commercial products using synthesized speech.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.6
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• pp.2464-2479
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• 2020

This paper presents a detailed subjective quality assessment for the ultra-high definition (UHD) videos having frame rates of 30fps and 60 fps. The subjective assessment is based on the ITU-R BT-500 recommendations, where double stimulus continuous quality scale (DSCQS-type II) test is performed for the evaluation of the perceived quality of the user's in terms of differential mean opinion score (DMOS). Encoding of the UHD videos by opting encoders i.e. H.264/AVC, H.265/HEVC, and VP9 at five different quantization parameter (QP) levels is done to investigate the perceived user's quality of experience (QoE) given as DMOS. Moreover, the encoding efficiency as the encoding time for each encoder and qualitative performance by employing full-reference (FR) quality metrics are presented in this work.

• Proceedings of the Korean Geotechical Society Conference
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• 1999.10a
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• pp.153-160
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• 1999

It has been recognized that the assessment of concrete lining is very uncertain and subjective depending on the engineers who are in charge. T-FLAS which was based on fuzzy theory was developed in this study for the quantitative and objective assessment of the concrete lining in tunnels. Based on the application of T-FLAS on the evaluated field data, it was shown that the assessment system using fuzzy theory(T-FLAS) can be the effective and objective method for the assessment of concrete lining.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.32 no.7
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• pp.561-568
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• 2008

The quality of the automatic transmission shift for a wheel loader has been generally evaluated by driver's perception. However the subjective evaluation of the drivers is not always directly related to the shift quality. It is necessary to set up the method for an objective assessment of the shift quality. In this paper, a quantitative assessment method has been developed for the shift quality of the automatic transmission in a wheel loader. The indices for the evaluation were selected through the various tests like the acceleration and the turbine rpm as well as the subjective evaluation of the driver, and were validated by the correlation between subjective and objective assessments using a psychophysical power law. Based on this method, the shift quality of a wheel loader has been evaluated quantitatively under various shift conditions.

• Journal of the Korean Institute of Navigation
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• v.18 no.4
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• pp.1-9
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• 1994

Assessment of the safety of ship's transit in the narrow channel consist of the maneuvering safety determined by the chance of running aground, the maneuvering difficulty determined by ship's workload and master's subjective evaluation. To examine the relation between master's subjective evaluation and maneuvering safety, this utilizes a real-time and full-mission shiphandling simulator in the Korea Marine Training & Research Institutes(KMTRI). The vessel chosen was 60,000-ton, Panamax-type ship. The findings regarding master's subjective evaluation were as follows: -Relation between master's subjective evaluation and common logarithms of stranding probability is linear. -Stranding probability with more than 0.001 is master's subjective evaluation with more than 5.

• Phonetics and Speech Sciences
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• v.3 no.3
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• pp.167-172
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• 2011

The purpose of this study was to examine the relationship between subjective and objective evaluation in speakers with voice disorders. Subjective evaluation indicates the self-reports of voice problems by dysphonic speakers. The relating protocol is the Voice Handicap Index (VHI) and the self-awareness index of voice problems (SAIVP-14). A total of 48 individuals with voice disorders replied to the questionnaire and participated in a voice assessment. Objective evaluations included the perceptual judgement of G grade in GRBAS, acoustic measurements (jitter, shimmer, NHR) by MDVP (CSL 4400), and aerodynamic measurements (MPT, MFR, psub) by PAS (Phonatory Aerodynamic System, KayPentax, USA). Pearson and Spearman correlations were used for the analysis. In the correlation with perceptual judgement (G grade) and VHI-Total, VHI-Physical, and SAIVP-14, there was a significant correlation, but the overall correlation was poor. NHR, jitter, and shimmer were significantly correlated with overall VHI and SAIVP-14. Specifically, the correlation with shimmer was stronger compared to the other measurements. In aerodynamic measures, MFR and MPT showed a significant correlation with VHI-Total, VHI-Emotional, and SAIVP-14, but their correlation was poor. The results of this study suggested that subjective evaluation of self voice problems is meaningfully correlated with objective evaluations, but more data in the multidimensional voice assessment should be collected and analyzed for the reliability and validity of the voice handicap questionnaire.