• Title/Summary/Keyword: objective measurement

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A survey on the visual fatigue measurement methods (시각피로의 측정방법에 관한 조사연구)

  • 이남식;박재희;김유창
    • Proceedings of the ESK Conference
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    • 1994.04a
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    • pp.32-37
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    • 1994
  • This paper surveys the various methodologies for the objective measurement of visual fatigue. Visual fatigue is a psychophysiological symtom caused by the excessive use of eyes and it can be used as an important measure of the effectiveness and the safety of visual displays. The purpose of this paper is to compare the various visual fatigue measurement methodologies in a sense of the suitability for the ergonomic research. The measurement methodologies based on accommodation, convergence, visual evoked potential, eye movement, eye blinking, and flicker fusion were discussed and compared.

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A New Effective Measure of the Block Effect in Still Images and Moving Pictures (정지영상 및 동영상에서의 효율적인 블록효과 측정방법)

  • 김문성;정진구
    • Journal of the Korea Society of Computer and Information
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    • v.7 no.4
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    • pp.102-107
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    • 2002
  • Compression coding based on block coding has been applied in image and video compression standard. But there is no block effect measurement due to block based image coding. In this paper, we propose a objective block effects measurement to reconstructed image using subblock DCT coding. Experimental results show that the block effects measures given by the suggested method agree well with the subjective ranking. This new objective measurement is simple and effective in measuring the block effect in the reconstructed image.

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On-Machine Measurement of Sculptured Surfaces Based on CAD/CAM/CAI Integration : I. Measurement Error Modeling (CAD/CAM/CAI 통합에 기초한 자유곡면의 On-Machine Measurement : I. 측정오차 모델링)

  • Cho, Myeong-Woo;Lee, Se-Hee;Seo, Tae-Il
    • Journal of the Korean Society for Precision Engineering
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    • v.16 no.10
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    • pp.172-181
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    • 1999
  • The objective of this research is to develop a measurement error model for sculptured surfaces in On-Machine Measurement (OMM) process based on a closed-loop configuration. The geometric error model of each axis of a vertical CNC Machining center is derived using a 4${\times}$4 homogeneous transformation matrix. The ideal locations of a touch-type probe for the scupltured surface measurement are calculated from the parametric surface representation and X-, Y- directional geometric errors of the machine. Also, the actual coordinates of the probe are calculated by considering the pre-travel variation of a probe and Z-directional geometric errors. Then, the step-by-step measurement error analysis method is suggested based on a closed-loop configuration of the machining center including workpiece and probe errors. The simulation study shows the simplicity and effectiveness of the proposed error modeling strategy.

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Measurement Error Modeling for On-Machine Measurement of Sculptured Surfaces

  • Cho, Myeong-Woo;Lee, Se-Hee;Seo, Tae-Il
    • International Journal of Precision Engineering and Manufacturing
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    • v.2 no.2
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    • pp.73-80
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    • 2001
  • The objective of this research is to develop a measurement error model for sculptured surface in On-Machine Measurement(OMM) process based on a closed-loop configuration. The geometric error model of each axis of a vertical CNC machining center is derived using a 4$\times$4 homogeneous transformation matrix. The ideal locations of a touch-type probe for the sculptured surface measurement are calculated from the parametric surface representation and X-, Y- directional geometric errors of the machine. Also the actual coordinates of the probe are calculated by considering the pre-travel variation of a probe and Z-directional geometric errors. Then, the step-by-sep measurement error analysis method is suggested based on a closed-loop configuration of the machining center including workpiece and probe errors. The simulation study shows the simplicity and effectiveness of the proposed error modeling strategy.

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A Study on Vehicle Steering Feel Using Objective Measurement (실차 계측을 이용한 차량 조향감 성능 연구)

  • Kim, Jung-Sik
    • Transactions of the Korean Society of Automotive Engineers
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    • v.15 no.4
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    • pp.161-170
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    • 2007
  • As one of the major handling performances of the vehicle and tire, the steering feel is very important in the high speed where safety and refinement is a major concern for the drivers. This paper presents both subjective and objective techniques for the assessment of the steering feel including the on-center feel and steering response. For this, subjective evaluation method of the steering feel was studied at first and then objective parameters were selected by considering the process by which the steering feel is evaluated subjectively. From statistical analysis of subjective and objective data for the several vehicles and professional drivers, it was found that the subjective assessment of the steering feel could be successfully explained by means of the suggested objective parameters. Also, the main objective parameters related to the subjective assessment of the steering feel could be found.

A Study on the Knowledge Assets Measurement Model for Korean Companies (국내기업의 지식자산 측정 모델 개발 연구)

  • 양경식;김현수
    • The Journal of Information Technology and Database
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    • v.8 no.2
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    • pp.115-135
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    • 2001
  • The objective of this paper is to develop a knowledge assets measurement model in Korea. There are relatively many researches on measuring knowledge assets of an organization. These previous researches, however, lack of comprehensive view of knowledge management and view of Korean organizational culture. We surveyed and analyzed previous researches, and found common factors to measure knowledge assets. We developed an updated version of knowledge assets index. The developed model has been validated for its fitness with real data of Korean companies. The result of this research can be used as a measurement tool for knowledge assets of public institutions as well as private companies.

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Estimation of Natural Period by Microtremor Measurement in Shearwall Apartments. (상시미동 측정을 통한 벽식아파트 건물의 고유주기)

  • 강호근
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 1999.10a
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    • pp.375-382
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    • 1999
  • The fundamental vibration period of a shearwall apartments cannot estimate accurately by means of empirical formulas specified in present codes, The objective of this paper is to estimate the period of a shearwall apartments by microtremor measurement. A micretremor is the continuous small oscillation of the ground cause by traffic and operation machinery. Microtremors are extensively studied primarily in Japan to estimate conveniently subsurface structures of soil deposits and building vibrations. It is obtained the results that the fundamental periods estimated by microtremor measurement are shorter than those values by dynamic analysis of building.

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Investment Effect Analysis of Industrial Firms with a Measurement Standard Laboratory -With Reference to the Statistical Analysis of Product Inferiority Rate- (측정표준실(測定標準室) 설치업체(設置業體)의 투자효과분석(投資效果分析) -제품(製品)의 불량률변동(不良率變動)의 통계적(統計的) 고찰(考察)을 중심(中心)으로-)

  • Kim, Dong-Jin;An, Ung-Hwan
    • Journal of Korean Society for Quality Management
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    • v.18 no.1
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    • pp.84-95
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    • 1990
  • The objective of this study is to understand the effect of measurement-related investment. That is, this study aims at verifying the correlation between the measurement-related investment and inferiority rate of products by statistical analysis. The samples of this study are 376 industrial companies in Korea, and the research data was analysed on inferiority state of industrial companies with a measurement standard laboratory. The analysis was made by the elementary statistics, the correlation analysis and the regression analysis. The results are summarized as follows : First, the inferioriy rate of the industrial companies with a measurement standard laboratory was relatively lower than that of the other companies without the laboratory by statistical significance. Second, the increment on measurement-related investment had a negative correlation with the increment of inferiority rate, and the increase of measurement-related investment showed decrease of the inferiority rate by regression analysis.

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An Analysis of Research on Fatigue (피로와 관련된 논문 분석)

  • 변영순;박미숙
    • Journal of Korean Academy of Nursing
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    • v.26 no.4
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    • pp.868-877
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    • 1996
  • This study was done to analyze research trends and to suggest future perspectives for nursing research on fatigue. The author reviewed 31 Korean and foreign research papers which have been published in the literature since 1970. An analysis of the study focused on the type of research subjects, type of study design. measurement instrument, and its correlated parameters. The results of the study are summarized as follows : First, within all of the studies analayzed, 14 studies were publised in Korea and 17 were published abroad. The number of studies done abroad have been increasing rapidly since 1991. Second, an analysis of the research design of the studies showed, eight studies each, Korean and foreign used survey design. Two Korean studies and seven foreign studies used a correlational design. Four comparative studies were done in Korea, but only two experimetal studies were performed abroad. Therefore, it was found that the trend of the study design used is survey design and there are more correlational studies done abroad than in Korea. Third, the type of the study subjects ; 11 Korean and three foreign studies dealt with healthy people. In addition, three Korean and 14 foreign studies investigated patients with various illnesses. It was found that patients with various illnesses were studied more frequently in foreign studies than in Korean studies. Fourth, the measurement tool used in the Korean studies ; 13 studies used a testible tool to assess patients' subjective symtoms or complaints of fatigue. The most commonly used tool used in 10 studies, was the Fatigue Self-Perception Scale, which was designed by the Labor and Health Institute of Japan. The Visual Analogue Scale was used in two studies, and Piper Fatigue Scale, addtional with physiologic parameters, was used in one study. In the foreign studies, subjective measurement tools were used in 16 studies. A combination of a subjective measurement tool with objective parameters was used in ten studies. For the subjective measurement tool used in the foreign studies, a specific measurement tool developed by the researcher which was used in seven studies. Either Rhoten Fatigue Scale or the Visual Analog Scale were used in three studies. Additionally, in order to identify the relationship between fatigue and psychological factors, The Profile of Mood State was used in three studies. Beck Depression Inventory was used in two studies. The Self Rated Depression Scale, developed by Zung, was used in one study and other measurement tools were used to measure various psychological parameters. Rhoten fatigue Checklist was also used to observe behavior patterns. Lastly, nine studies identified correlations between fatigue and other parameters. A significant correlation was found between fatigue and psychological factors such as depression, and pain. As a result of the above findings, it can be said that research trends on fatigue are increasing internationally. The selected study designs are survey studies both in Korea and abroad. There are more correlational studies abroad than in Korea. In addition, subjective measurement tools and objective parameters are used variously and combined with each other. had, there is a significant correlation between fatigue and psychological factors such as depression, and pain. More survey and correlational studies need to be done to identify the relationship of fatigue in patients with various condition or diagnoses and to suggest a scientific basis for nursing interventions with fatigue. Also, a tool to assess patient's subjective, objective, and behavioral aspects on fatigue needs to be developed.

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Review on the Objective Effect and Mechanism Studies of Herbal Medicine, Acupuncture and Moxibustion Treatment for Irritable Bowel Syndrome Patients (과민성 대장증후군 환자를 대상으로 수행된 한약 및 침구치료의 객관적 효과와 기전 연구에 대한 문헌고찰)

  • Noh, Hyun Deok;Kim, Min Jeong;Cho, Im Hak;Kim, So Yeon
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.35 no.5
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    • pp.199-209
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    • 2021
  • The purpose of this study was to explore objective indicators(outcomes) which are used to evaluate clinical efficacy and figure out the mechanisms of herbal medicine, acupuncture and moxibustion treatment for Irritable bowel syndrome(IBS). We searched randomized controlled trials(RCTs) that mediated with herbal medicine, acupuncture and moxibustion treatment for IBS and used objective indicators for outcome from November 1, 2020 to December 31, 2020. The RCTs that were published in Korean, English and Chinese were included in this study. The selected literatures were analyzed about methods of result measurement and assessed by Cochrane's risk of bias(RoB). Total 18 RCTs were included in this study. There were lots of objective indicators for result measurement; the concentration of hormones in blood and neurotransmitters, the sensitivity of rectum, the functional assessment of central nerve and autonomic nerve system, the change of intestinal flora, the concentration of serum cytokines. Various objective indicators can be used to evaluate the clinical efficacy of with herbal medicine, acupuncture and moxibustion treatment for IBS, but due to the limitations of the quality of the included studies, systematic review and meta-analysis will be needed.