• 대한인간공학회지
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• 제30권6호
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• pp.695-703
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• 2011

Objective: This study was to investigate the effects of coordinated upper-limb body postures on the subjective discomfort rating, heart rate, and muscle activities. Background: Although generally many checklists such as OWAS, RULA, and REBA were applied to evaluate various body postures, the body postures were might be overestimated or underestimated because each body part(i.e., back, shoulder, and elbow etc.) was evaluated separately, and then added all rates of individual body parts to assess an overall risk level for the body posture in these methodologies. Methods: A total of 20 participants maintained 14 postures which were combinations of back, shoulder, and elbow flexion angles and then muscle activities, subjective discomfort, and heart rates were collected every three minute during a sustained 15 minute and 0.5kg weight holding task. Four muscle groups were investigated: erector spine, anterior deltoid, upper trapezius, triceps brachii. Results: Results showed that subjective discomfort was the lowest when the angle of back and shoulder were both $0^{\circ}s$, while the body posture with $45^{\circ}$ of back angle and $45^{\circ}$ shoulder angle was rated as the most subjective discomfort posture. In general, the subjective discomfort ratings increased as back and shoulder flexion angles increased. It was noted that, however, the subjective discomfort of body posture with a $45^{\circ}$ back angle and $45^{\circ}$ shoulder flexion angle was lower than that of body posture with a $0^{\circ}$ back and $45^{\circ}$ shoulder flexion angle. The research findings of heart rates and muscle activities showed similar results for the analyses of subjective discomfort ratings. Conclusions: The possible limitations of the current ergonomics evaluation techniques which assessing a body posture with summing all body part score after individually analyzed in this study. Based on the analyses of subjective discomfort, heart rate, and muscle activities, it was recommended that a use of effects of coordinated upper-limb body postures would be considered when one evaluates work-load for various working postures. Application: These findings can be used for developing a more accurate assessment checklist for working posture as well as preventing musculoskeletal disorders of workers in workplaces.

• 지역사회간호학회지
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• 제29권2호
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• pp.184-193
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• 2018

Purpose: The aim of this study is to examine a path model on the relationship among social capital, physical activity and subjective health status in the community indwelling elderly. Methods: The study was conducted utilizing the 2014 Seoul Survey, in the method of analyzing cross-sectional design and secondary data. Among 45,497 participants in total, the data of 4578 adults aged 65 or above was analyzed. Social capital was measured by social trust and social participation. Physical activity was measured by regular exercise. Additionally, a numerical rating scale was used to assess subjective health status. The data were analyzed using descriptive statistics, Pearson's correlation coefficients and path analysis. Results: Social participation and physical activity showed a direct effect on subjective health status in community indwelling elderly while social trust and physical activity showed an indirect effect on their subjective health status. The hypothetical path model of community indwelling elderly's subjective health status was proved correct. Conclusion: Findings from this study indicate that health-promoting intervention for community indwelling elderly should consider social trust and participation.

• 감성과학
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• 제2권2호
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• pp.37-42
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• 1999

Long-term exposure to loud noise affects performance since it changes arousal level, distracts attention, and also is able to evoke subjective stress accompanied by negative emotional states. The purpose of the study was to analyze dynamics of subjective and physiological variables during a relatively long-lasting (30 min) exposure to white noise (85 dB[A]). Physiological signals were recorded on 15 college students during 30 min of intense auditory stimulation. Autonomic variables, namely skin conductance level , non-specific SCR number, inter-best intervals in ECG, heart rate variability index (HF/LF ratio of HRV), skin temperature, as well as respiration rate were analyzed on 5 min epoch basis. Psychological assessment (subjective rating of stress level) was also repeated every 5 min. Statistical analysis was employed to trace the time course of the dynamics of subjective and autonomic physiological variables and their relationships. Results showed that the intense noise evoked subjective stress as well as associated autonomic nervous system responses. However it was shown that physiological variables endured specific changes in the process of exposure to the loud white noise. Discussed were probable psychophysiological mechanisms mediating reactivity to long-term auditory stimulation of high intensity, namely short-term activation, followed by transient adaptation (with relatively stable autonomic balance) and then a subsequent wave of arousal due to tonic sympathetic dominance.

• 대한인간공학회:학술대회논문집
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• 대한인간공학회 1998년도 춘계학술대회논문집
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• pp.36-39
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• 1998

In this study, the postural stresses in automobile assembly tasks were evaluated through an experiment. We had 19 subjects who simulated 42 different working postures occuring in the automobile assembly tasks for1 min and rated their whole body discomforts subjectively. We sued a free modulus magnitude estimation technique, commonly used as a psycophysical rating technique, and fully trained the subjects for the technique. The postures were selected through the analysis of the characteristics of te automobile assembly tasks and the expected difficulties. The subjective discomfort rating data were normalized by min-max standardization method. The consistency of the rating data was guaranteed by the analysis of spear man rank-order. The postures were ranked on their ratings and the relationships between the whole body discomfort ratings, and joint discomfort ratings were analysed. It is expected taht a system for evaluating postural stresses, which was specific to automobile assembly tasks, can be developed based on the relationship and can also be expended to a general purpose system with a minor modification.

• 대한음성학회:학술대회논문집
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• 대한음성학회 2007년도 한국음성과학회 공동학술대회 발표논문집
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• pp.257-260
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• 2007

This study was designed to compare the self-rating scales (SSS, S-24, P-FA, and PSI) translated into Korean in adults with stuttering. Eighteen adults with stuttering were participated. Each scale was divided into two sub-categories, avoidance and locus of control. The correlations among the scales and among the sub-categories were evaluated. Objective stuttering severity and self-rated stuttering severity were compared. Results indicated that those scales were significantly correlated. Total score in each scale and each sub-category were also significantly correlated. There were no significant differences in total score nor subjective stuttering severity with objective stuttering severity. The self-rating scales in adults with stuttering currently used in clinics and research areas in Korea are suitable tools that adults with stuttering can evaluate the characteristics of and attitudes for stuttering subjectively.

• 한국음향학회:학술대회논문집
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• 한국음향학회 1994년도 FIFTH WESTERN PACIFIC REGIONAL ACOUSTICS CONFERENCE SEOUL KOREA
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• pp.1070-1075
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• 1994

This paper describes the method for designing loudness ratings as transmission quality for ISDN telephone connected to fully digital network. To design the desirable loudness ratings for ISDN telephone, the model system of digital speech communication for subjective test is developed and opinion tests for establishing the optimal CODEC input level, the range of overall loudness rating, and sidetone masking rating are performed. As the results, the desirable ranges of loudness ratings are proposed as 6 to 8dB for sending, 0 to 2dB for receiving, and 10 to 14dB for sidetone masking rating.

• Tribology and Lubricants
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• 제13권2호
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• pp.8-15
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• 1997

It is very difficult to express the state of a tested engine objectively concerning the malfunction, failure and wear of an engine. The general method of engine evaluation is to express evaluator's opinion for the engine state after testing. However, these methods is only subjective evaluation because test engineers, designers, and evaluators does not easily coincide in opinion. Therefore, in this article, the method of engine rating are introduced in order to represent the qualitative trends into quantitative value. The purpose of Engine Rating is to assign a quantified value to the tribology state of a tested engines. Originally, this Engine Rating method have been used to evaluate the performance of engine oil quantitavely. Using this method, we can predict the proper interval of engine oil change due to its objectivity. So, we can prevent the frequent change of engine oil and protect the environmental contamination. Furthermore, this method can be used to tell the general state of a tested engine after finishing engine durability tests. A single merit scale is used to evaluate numerically the state of cleanliness and the mechanical condition. Generally, a part which is absolutely clean or shows no wear, is rated merit 10. A part which is absolutely dirty or very worn, is rated merit 0.

• 한국수자원학회논문집
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• 제55권7호
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• pp.557-563
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• 2022

수위-유량관계곡선식은 측정된 수위를 유량으로 변환하는 데 필요하며 유량측정 성과를 이용하여 개발된다. 수위-유량관계곡선식 개발에서 구간분리 위치는 수리적 특성과 하천단면 형상 등을 고려하여 결정되며 이 과정에서 개발자의 주관적인 판단이 개입되는 경우가 있다. 구간분리 위치는 수위-유량관계곡선식의 전체적인 형태를 결정할 정도로 중요하고 잘못된 구간분리는 수위-유량관계곡선식의 오류를 유발하게 되며 특히 외삽구간에서 큰 오류가 발생할 가능성이 높다. 또한 예산, 인력 등의 문제로 많지 않은 유량측정성과로 정확한 수위-유량관계곡선식을 개발하려면 하천의 단면형상 및 흐름 특성 등 수리적인 요소를 고려하여 구간을 분할해야 한다. 본 연구에서는 기존의 수위-평균유속, 수위-단면적, 수위-${\sqrt{Q}}$ 등 수리적 검토 방법을 살펴보고 이를 보완하여 구간분리 위치 결정에 있어서 주관성을 배제하고자 하였다. 구간분리 위치에 대한 적절성을 수위-유량관계곡선식 지수 (c)의 물리적인 의미를 고려하여 이를 검토하였다.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2005년도 춘계학술발표회
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• pp.825-826
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• 2005

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 가을 학술발표회 논문집(II)
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• pp.1285-1290
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• 2000

The inspection of bridge condition is of extreme importance. Current inspection codes for bridge inspection are vague and uncertain. So, the results are highly subjective and different from person to person and even day to day for a given person. To circumvent possible inconsistencies in inspection and rating of bridge components, the revised inspection guidelines have been proposed.