• 제목/요약/키워드: Perceived discomfort

검색결과 146건 처리시간 0.023초

화소 밀집도, 화소 하부구조, 휘도, 조명 조도가 스마트폰 가독성에 미치는 영향 (The effects of pixel density, sub-pixel structure, luminance, and illumination on legibility of smartphone)

  • 박종진;이형철;김신우
    • 감성과학
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    • 제17권3호
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    • pp.3-14
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    • 2014
  • 2009년 아이폰의 국내 출시 이후 스마트폰의 보급이 급격히 증가하여 기존에 다양한 장비로 수행되어 오던 작업이 스마트폰으로 대체되었다. 이 과정에서 스마트폰의 작은 화면을 통하여 글자를 읽는 과제를 수행하는 비중이 상당히 증가하였다. 본 연구에서는 일상적인 스마트폰 사용 환경에서 디스플레이 요인(화소 밀집도, 화소 하부구조, 휘도)과 환경 요인(조명 조도)이 글자를 읽을 때의 가독성 관련 불편감에 어떤 영향을 미치는지를 확인하였다. 그 결과 지각된 가독성 관련 불편감에 영향을 미치는 것은 주로 화소 밀집도로, 화소 밀집도가 300 PPI미만인 경우 글자를 읽는데 불편함을 느낀다는 것을 확인하였다. 조명 조도는 제한적인 영향을 보였다. 참가자들은 조명 조도가 변화 할 때 변화하지 않을 때 보다 더 큰 가독성 관련 불편감을 보고하였다. 화소 하부구조와 밝기는 가독성 관련 불편감에 영향을 미치지 않았다. 이 결과를 바탕으로 가독성을 고려할 때 다양한 크기를 가지는 스마트 기기(스마트 폰, 태블릿 컴퓨터)에서 가독성을 해치지 않는 해상도의 하한선을 제안하였다.

지각불편도를 이용한 관찰적 작업자세 평가 기법의 비교 (Comparison of observational posture evaluation methods based on perceived discomfort)

  • 이인석;정민근;최경임
    • 대한인간공학회지
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    • 제22권1호
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    • pp.43-56
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    • 2003
  • Observational methods such as OWAS, RULA, and REBA have been widely used to identify posture-related risks of musculoskeletal disorders in industry, since they are useful and efficient in evaluating postural stresses. However. there are few studies comparing the methods and providing guidelines for selecting and using the methods. They have been developed based on different backgrounds and with different application areas. Each method has its own characteristics. which must be considered in selecting and using them. In this study. 17 male subjects evaluated 42 different working postures that frequently assumed in the automobile assembly line using a psychophysical method. The postures were then evaluated by different observational methods. The results of the observational methods were compared with psychophysically evaluated stresses. The observational methods resulted in different values of stresses for certain postures. For some postures showing high values of perceived discomfort. the observational methods showed different values of stresses. These results showed that the observational methods should be used differently according to application area and they have some weak points to be improved.

인지온도를 이용한 여름철 폭염 스트레스와 일 사망률 증가와의 관련성 연구: 1991~2005, 서울 (Relationship between Summer Heat Stress (Perceived Temperature) and Daily Excess Mortality in Seoul during 1991~2005)

  • 이대근;변재영;최영진;김규랑
    • 한국대기환경학회지
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    • 제26권3호
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    • pp.253-264
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    • 2010
  • This study investigates the relationship between daily mortality and heat stress in Seoul, using perceived temperatures (PT) derived from a heat budget model. During the summer season, observed PT intensity showed the biggest magnitude of summer heat stress from the middle 10 days of July to the first 10 days of August. The elderly (65 and above) were found to be the most vulnerable to heat stress. The threshold PT, with a significant increase in excess mortality, was $38^{\circ}C$. No time lagged effect was observed with summer heat stress, while a high correlation was observed between anomalies in PT and relative deviation of mortality. A comparison of the heat index and the discomfort index with excess mortality revealed that the discomfort index underestimated excess mortality, whereas the heat index could not appropriately explain the increase in excess mortality correlated with the increase in excess heat. In contrast, PT was found to be the weather element that best represents excess mortality due to heat stress, and is thus expected to serve as a more reliable forecast index of human biometeorology.

한반도 2007년 여름철 인지온도 특성 연구 (A Study on the Characteristics of Perceived Temperature over the Korean Peninsula During 2007 Summer)

  • 변재영;김정식;김지영;최병철;최영진
    • 대기
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    • 제18권2호
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    • pp.137-146
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    • 2008
  • This study examines one thermal index, perceived temperature (PT), over the Korean Peninsula during 2007 summer. Heat/cold stress has been described using air temperature and humidity for warm seasons and air temperature and wind velocity in the cold conditions, while PT is based on a heat budget model of the human body that considers air temperature, humidity, wind velocity and radiation effect regardless of climates, regions and seasons. PT is higher about $4-5^{\circ}C$ than air temperature in the summer. Humidity increases PT, while wind tends to reduces PT possibly by evaporation of water vapor. The geographical distribution of summer PT indicates that the lowest PT happened in the east central region, with the appearance of the highest PT in the inland of southern region in Korea. Although the latitudinal trend shows that PT decreases northward, inland PT is higher than that of coastal region. Compared to the heat index or the discomfort index that considers air temperature and humidity, PT represents distinctive regional characteristics of thermal comfort. The distribution of PT shows that it may be a useful thermal index for the assessment of thermal comfort or stress region in the Korean Peninsula.

손목 동작의 반복과 외부 부하에 따른 심물리학적 부하 (Psychophysical Stess Depending on Repetition of Wrist Motion and External Load)

  • 기도형
    • 한국안전학회지
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    • 제19권4호
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    • pp.123-128
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    • 2004
  • This study investigated effect of arm posture, repetition of wrist motion and external load on perceived discomfort. The arm postures were controlled by shoulder flexion, elbow flexion, and ist motions such as flexion, extension, radial deviation and ulnar deviation. An experiment was conducted to measure discomfort scores for experimental treatments using the magnitude estimation, in which the L16 orthogonal array was adopted for reducing the size of experiment. The results showed that while the effect of the shoulder flexion, repetition of wrist motion and external load was statistically significant at $\alpha=0.05$or 0.10, that of the elbow and wrist motions was not. Discomfor ratings increased linearly as levels of wrist repetition and external load increased. This implies that the existing posture classification schemes such as OWAS, RULA, which do not properly consider effect of motion repetition and external load, may underestimate postural load. Based on the regression equation for wrist repetition and external load, isocomfort region indicating the region within which discomfort scores were expected to be the same was proposed. It is recommended that when assessing risk of postures or developing new posture classification schemes, motion repetition and external load as well as posture itself be fully taken into consideration for precisely evaluating postural stress.

만성요통 환자들에서 스트레스지각과 대응전략 간의 관계 (The Relationship between Perceived Stress and Coping Strategies in Patients with Chronic Low Back Pain)

  • 신윤식;고경봉
    • 정신신체의학
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    • 제10권1호
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    • pp.18-26
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    • 2002
  • 연구목적: 본 연구의 목적은 만성요통 환자에서 스트레스지각 및 통증지각과 대응전략 간의 관계를 알아보고자 하는데 있다. 본 연구에는 만성요통 환자 80명과 정상대조군 100명이 참여하였다. 방법: 스트레스인자 및 스트레스반응에 대한 지각은 각각 스트레스인자 지각척도 (Global Assessment of Recent Stress Scale) 및 스트레스반응 척도(Stress Response Inventory)를, 대응전략 및 통증지각은 각각 대응척도(The Way of Coping-revised) 및 통증지각척도(Pain Discomfort Scale)를 이용하여 평가하였다. 결과: 만성요통환자들이 정상대조군보다 일 및 직장, 대인관계, 대인관계의 변화, 질병 및 상해에 관련된 스트레스인자 지각점수, 전체 스트레스인자지각 정수가 각각 유의하게 더 높았다. 스트레스반응점수에서는 피로점수가 정상대조군보다 환자군에서 유의하게 더 높았으나, 통증지각에서는 양군 간에 유의한 차이를 보이지 않았다. 대응전략에서는 환자군이 정상대조군에 비해 계획적 문제해결 및 긍정적 재평가를 더 많이 사용하였다. 환자군에서 통증지각은 전체 스트레스반응 점수, 질병 및 상해에 관련한 스트레스인자지각 점수와 각각 유의한 양상관성을 보였다. 도피 회피 점수는 연령과 유의한 음상관성을, 거리감두기 및 도피-회피 점수는 유의한 양상관성을 보였다. 한편 책임수용은 여자가 남자보다 더 유의하게 많이 사용하였다. 그러나 대응전략과 스트레스인자지각 및 스트레스반응 통증지각 간에는 각각 유의한 상관성을 보이지 않았다. 결론: 이상의 결과들은 만성요통환자들이 정상인에 비해 스트레스인자에 대한 지각이 더 높으나, 더 적극적인 대응을 하고 있음을 시사한다. 또한 환자군에서 사용하는 대응전략은 스트레스인자지각, 스트레스반응, 통증지각과 연관성을 보이지 않는 반면 사회인구학적 특정들과 연광성이 높음을 시사한다.

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Reach 동작예측 모델의 개발 (A trajectory prediction of human reach)

  • 최재호;정의승
    • 한국경영과학회:학술대회논문집
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    • 대한산업공학회/한국경영과학회 1995년도 춘계공동학술대회논문집; 전남대학교; 28-29 Apr. 1995
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    • pp.787-796
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    • 1995
  • A man model is a useful design tool for the evaluation of man machine systems and products. An arm reach trajectory prediction for such a model will be specifically useful to present human activities and, consequently, could increase the accuracy and reality of the evaluation. In this study, a three-dimensional reach trajectory prediction model was developed using an inverse kinematics technique. The upper body was modeled as a four link open kinematic chain with seven degrees of freedom. The Resolved Motion Method used for the robot kinematics problem was used to predict the joint movements. The cost function of the perceived discomfort developed using the central composite design was also used as a performance function. This model predicts the posture by moving the joints to minimize the discomfort on the constraint of the end effector velocity directed to a target point. The results of the pairwise t-test showed that all the joint coordinates except the shoulder joint's showed statistically no differences at .alpha. = 0.01. The reach trajectory prediction model developed in this study was found to accurately simulate human arm reach trajectory and the model will help understand the human arm reach movement.

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Measurement on comfort range of korean population's joint motions for designing and evaluating workplaces

  • 기도형
    • 대한인간공학회지
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    • 제16권2호
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    • pp.73-82
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    • 1997
  • Daily exposure to constrained body postures and deviations from neutral postures over a long period may result in discomfort as well as pains and aches in the muscles, joints, tendons, and other soft tissues. Furthermore, it was known that poor body postures are a major cause of musculoskeletal disorders in industry. Therefore, in this study, comfort ranges of joint motions were obtained as a criterion for evaluating body postures and designing workplaces ergonomically, which were bases on subjects' perceived discomfort level estimated by magnitude estimation. Nineteen healthy male subjects participated in the laboratory study. They results showed that comfort ranges of joint motions occurred in the wrist, elbow, neck, and ankle were little less than their normal range of joint motions, but those in the back(L5/S1) and hip joint were much less than their normal ones. This fact implies that the back and jip movements are more stressful than the other joints movements. It is expected that comfort ranges of joint motions can be used as a valuable guideline when designing and evaluating workplaces.

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일회용 전신 보호복의 온열 스트레스 분석 (A Thermal Stress Analysis of Disposable Personal Protective Coveralls)

  • 박소영;이예진
    • 한국의류학회지
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    • 제47권6호
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    • pp.1193-1203
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    • 2023
  • This study aims to provide primary data regarding the thermal stress of disposable personal protective coveralls. Thermal stress and surface temperature measurements were taken among ten men wearing coveralls. The size of the ten men corresponds to a size eight in Size Korea. As a result of thermal stress, sensations of humidity and discomfort were higher when wearing Level C compared to Level D. Level D felt significant thermal stress in their upper body after exercise. However, they did not feel such stress in their lower body. Level C felt thermal stress in their upper and lower body after exercise. In addition, in Level C, the ratings of perceived exertion blood pressure and pulse rate after exercise were higher than those of Level D. Furthermore, the surface temperature of disposable personal protective coveralls among Level C was slightly higher than that of Level D.

인공지능 기반 기술에 대한 공공도서관 사서의 사용의도 연구 (A Study on the Intention of Public Library Librarians to Use Artificial Intelligence-Based Technology)

  • 김지영
    • 한국문헌정보학회지
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    • 제57권3호
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    • pp.163-190
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    • 2023
  • 본 연구는 기술수용모델을 활용하여 기술준비도와 기술수용요인이 인공지능 기반 기술에 대한 공공도서관 사서의 사용의도에 미치는 영향을 분석하였다. 이를 위하여 공공도서관 사서를 대상으로 설문조사를 실시하였으며 총 202명의 설문 데이터를 통계 분석에 활용하였다. 가설검증 결과 첫째, 지각된 유용성에 낙관성은 유의한 정(+)의 영향을 미치는 것으로 나타났고 불편함은 유의한 부(-)의 영향을 미치는 것으로 나타났다. 지각된 용이성에 낙관성과 혁신성은 유의한 정(+)의 영향을 미치는 것으로 나타났으며 불편함은 유의한 부(-)의 영향을 미치는 것으로 나타났다. 둘째, 지각된 용이성은 지각된 유용성에 유의한 정(+)의 영향을 미치는 것으로 나타났으며 지각된 유용성과 지각된 용이성은 모두 사용의도에 유의한 정(+)의 영향을 미치는 것으로 나타났다. 셋째, 사용의도에 낙관성은 유의한 정(+)의 영향을 미치는 것으로 나타났으며, 불안감은 유의한 부(-)의 영향을 미치는 것으로 나타났다. 본 연구는 인공지능 기반 기술에 대한 공공도서관 사서의 인식을 실증적으로 분석하여 향후 인공지능 기술의 도서관 활용에 대한 기초적인 자료를 제공할 수 있을 것으로 기대한다.