• Title/Summary/Keyword: Measurement scale

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Evaluation on bridge dynamic properties and VIV performance based on wind tunnel test and field measurement

  • Yang, Yongxin;Ma, Tingting;Ge, Yaojun
    • Wind and Structures
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    • v.20 no.6
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    • pp.719-737
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    • 2015
  • Full scale measurement on the structural dynamic characteristics and Vortex-induced Vibrations (VIV) of a long-span suspension bridge with a central span of 1650 m were conducted. Different Finite Element (FE) modeling principles for the separated twin-box girder were compared and evaluated with the field vibration test results, and the double-spine model was determined to be the best simulation model, but certain modification still needs to be made which will affect the basic modeling parameters and the dynamic response prediction values of corresponding wind tunnel tests. Based on the FE modal analysis results, small-scaled and large-scaled sectional model tests were both carried out to investigate the VIV responses, and probable Reynolds Number effects or scale effect on VIV responses were presented. Based on the observed VIV modes in the field measurement, the VIV results obtained from sectional model tests were converted into those of the three-dimensional (3D) full-scale bridge and subsequently compared with field measurement results. It is indicated that the large-scaled sectional model test can probably provide a reasonable and effective prediction on VIV response.

Field measurement-based wind-induced response analysis of multi-tower building with tuned mass damper

  • Chen, Xin;Zhang, Zhiqiang;Li, Aiqun;Hu, Liang;Liu, Xianming;Fan, Zhong;Sun, Peng
    • Wind and Structures
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    • v.32 no.2
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    • pp.143-159
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    • 2021
  • The 246.8-m-tall Beijing Olympic Tower (BOT) is a new landmark in Beijing City, China. Its unique architectural style with five sub-towers and a large tower crown gives rise to complex dynamic characteristics. Thus, it is wind-sensitive, and a double-stage pendulum tuned mass damper (DPTMD) has been installed for vibration mitigation. In this study, a finite-element analysis of the wind-induced responses of the tower based on full-scale measurement results was performed. First, the structure of the BOT and the full-scale measurement are introduced. According to the measured dynamic characteristics of the BOT, such as the natural frequencies, modal shapes, and damping ratios, an accurate finite-element model (FEM) was established and updated. On the basis of wind measurements, as well as wind-tunnel test results, the wind load on the model was calculated. Then, the wind-induced responses of the BOT with the DPTMD were obtained and compared with the measured responses to assess the numerical wind-induced response analysis method. Finally, the wind-induced serviceability of the BOT was evaluated according to the field measurement results for the wind-induced response and was found to be satisfactory for human comfort.

Development of Measurement Scale for the Quality of Life in Hypertensive Patients (고혈압 환자의 삶의 질 측정도구 개발)

  • Kim, Keon-Yeop;Kam, Sin;Lee, Sang-Won;Park, Ki-Soo;Chae, Shung-Chull;Chun, Byung-Yeol
    • Journal of Preventive Medicine and Public Health
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    • v.38 no.1
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    • pp.61-70
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    • 2005
  • Objectives : To develop a tool for multidimensional measurement of the quality of life, which was psychometrically sound, short, and easy to administer for patients with hypertension. Methods : A sample of 1,115 hypertensive patients aged 20 or above in Cheong-Song County was studied from June 1997 to October 1998. In the development of the instrumental stage, the authors first conceptualized the quality of life. Item generation, item reduction, and questionnaire formatting were followed. Item-level (item descriptive, missing%, item internal consistency, item discriminant validity) analysis, scale-level (scale descriptive, floor and ceiling effect) analysis, and other tests(Cronbach's alpha, inter-dimension correlations, factor analysis, clinical validity) were performed to evaluate the validity and reliability of the new measurement scale. After 1 year, responsiveness and confirmatory factor analysis were performed. Results : The results of both item-level and scale-level analyses were acceptable. An acceptable degree of internal consistency was observed for each of the dimensions (Cronbach's alpha was 0.60 or higher). Inter-dimension correlations were below 0.50 and the factor analysis result was the same as the intended dimension structure. Correlation coefficients between perceived health status, stress and dimensions were proven to be acceptable. The result of comparing dimensional score means among ADL and MMSE-K groups above 60 years was statistically significant(p<0.05). The result of confirmatory factor analysis concluded that the dimensional structure model was well fitted. However, the result of responsiveness test using sensitivity and specificity was unsatisfactory. Conclusions : The newly developed measurement scale is psychometrically reliable and valid instrument for measuring quality of life in hypertensive patients.

The Study For Clinical Measurement of Pain (통증(痛症)의 임상적평가법(臨床的評價法)에 관한 고찰(考察))

  • Shin, Seung-Uoo;Chung, Seok-Hee;Lee, Jong-Soo;Shin, Hyun-Dae;Kim, Sung-Soo
    • The Journal of Dong Guk Oriental Medicine
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    • v.8 no.2
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    • pp.25-46
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    • 2000
  • Pain can be evaluated by experimental methods and clinical methods, but due to subjective characteristics of pain, clinical methods are generally used. The clinical pain measurement tools are divided into unidimensional and multidimensional assessment tools. The former include Visual Analogue Scale, Verbal Rating Scale, Numerical Rating Scale, Pain Faces Scale, and Poker Chip Tool and the latter include McGill Pain Questionnaire, MMPI, Pain Behavior Scale, Pain disability index, and Pain Rating Scale. Unidimensional pain scales mainly measure the intensity of pain on the basis of the patient's self report and their simple construction and ease of use enable the invesgator to assess acute pain. Multidimensional pain scales are used to evaluate subjective, psychological and behavioral aspects of pain and because of its comprehensive and confidential properties they are applied to chronic pain. Patient's linguistic and cognitive abilities are major factors to restrain accurate assessment of pain. Although behavioral patterns and vital sign are inferior to self-report in the measurement of pain, they can be useful indexes in those situations. When deciding on a pain-assessment tool, the investigator must determine which aspect of pain he or she wishes to evaluate on the characteristics of the group of patients, their backgrounds, and their communication skills. Making the proper choice will facilitate the acquisition of meaningful data and the formulation of valid conclusions.

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A Study on the Measurement of the Crack Length for the Real Scale Pipe Specimen (실배관 시험편의 균열 길이 측정에 관한 연구)

  • Park, Jae-Sil;Seok, Chang-Sung
    • Proceedings of the KSME Conference
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    • 2003.04a
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    • pp.397-402
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    • 2003
  • Fracture resistance curves for concerned materials are required in order to perform elastic-plastic fracture mechanical analyses. Fracture resistance curve is built with J-integral values and crack extension values. The objective of this paper is to apply the load ratio method to the measurement of the crack length for the real scale pipe specimen. For these, the fracture test using the real scale pipe specimen and finite element analyses were performed. A 4-point bending jig was manufactured for the pipe test and the direct current potential drop method and the load ratio method was used to measure the crack extension and the length for the real scale pipe test. Finite element analyses about the compliance of the pipe specimen were executed for applying the load ratio method according to the crack length.

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Linear Measurement Error Variance Estimation based on the Complex Sample Survey Data

  • Heo, Sunyeong;Chang, Duk-Joon
    • Journal of Integrative Natural Science
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    • v.5 no.3
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    • pp.157-162
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    • 2012
  • Measurement error is one of main source of error in survey. It is generally defined as the difference between an observed value and an underlying true value. An observed value with error may be expressed as a function of the true value plus error term. In some cases, the measurement error variance may be also a function of the unknown true value. The error variance function can be rewritten as a function of true value multiplied by a scale factor. This research explore methods for estimation of the measurement error variance based on the data from complex sampling design. We consider the case in which the variance of mesurement error is a linear function of unknown true value, and the error variance scale factor is small. We applied our results to the U.S. Third National Health and Nutrition Examination Survey (the U.S. NHANES III) data for empirical analyses, which has replicate measurements for relatively small subset of initial respondents's group.

Development of Measurement Scale for Clothing Shopping Orientation - Merchandise/store Related Measurement Scales Development - (의복 쇼핑 성향의 측정 도구 개발(제2보) -상품/점포 관련 의복 쇼핑 성향 측정 도구 개발을 중심으로-)

  • Kim Saehee;Rhee Eunyoung
    • Journal of the Korean Society of Clothing and Textiles
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    • v.29 no.3_4 s.141
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    • pp.491-501
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    • 2005
  • The purpose of this study is to develop clothing shopping orientation(CSO) scales fer more specific clothing shopping aspects. The specific aspects were the merchandise-related aspect and the store-related aspect. The two specific scales were developed based on the conceptual structure model of CSO and the general CSO scale. 16 items were selected for merchandise-related CSO, and 16 items were far store-related CSO. In addition, construct validity and convergent validity of those two specific scales were verified using AMOS 4.0, and discriminant validity were verified using Pearson's correlation. This study has significance in offering an advanced approach to the measurement of CSO.

Reliability of Visual Analog Scale in Assessment of Acute Pain (시각적 상사 척도의 신뢰도 검사 -급성 통증 측정-)

  • Choi, Ja-Yun
    • The Journal of Korean Academic Society of Nursing Education
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    • v.9 no.1
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    • pp.136-143
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    • 2003
  • The purpose of this study was to test the reliability of visual analog scale in assessing the degree of acute pain related to blood sugar test. A sample of 113 subjects is composed of 56 DM patients and 57 their family who are admitted in a ward of medical part of C university hospital in Gwangju. Data are collected from July, 2001 to December, 2001. The degree of pain is twice measured in a week interval. Correlations were moderate between times in DM patients group and healty group. In both measures, correlations were high between VAS score and the score of color pain circle measurement tool. Visual analog scale is methodologically sound instrument for assessment of acute pain. Further study will be needed to evaluate the correlation with physiology measurement.

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A Study on the Difference in Expectation-Performance of Service Recovery Measurement Scale's 4 Dimensions both Korean Native Cattle Beef and Imported Beef Restaurant

  • Cho, Yoon-Shik;Lee, Mi-Ock
    • Journal of the Korean Data and Information Science Society
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    • v.19 no.4
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    • pp.1123-1131
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    • 2008
  • A considerable amount of research has focused on the dimensionality of service failure and recovery construct. This paper is focused on service failure and recovery in the Korean native cattle and imported beef restaurant industry in the Korea. So, this paper has adapted Kau and Loh's Service recovery measurement scale so that restaurant managers can use it to determine how customers perceive the service quality in Korean native cattle beef restaurant and imported beef restaurant. The purpose of this research is to test the difference in pre-purchase expectation and post-purchase actual performance of 4 dimensions between the restaurants that sell the beef of Korean native cattle and imported cattle. The paired t -test is used to test difference of pre-purchase expectation and post-purchase actual performance for service recovery measurement scale's 4 dimensions of the 2 restaurant types. But, there is significant difference between pre-purchase expectation and post-purchase actual performance in the 2 restaurant types.

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Development of Facial Palsy Grading System with Three Dimensional Image Processing (3차원 영상처리를 이용한 안면마비 평가시스템 개발)

  • Jang, M.;Shin, S.H.
    • Journal of rehabilitation welfare engineering & assistive technology
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    • v.9 no.2
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    • pp.129-135
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    • 2015
  • The objective grading system for the facial palsy is needed. In this study, the facial palsy grading system was developed with combination of three dimensional image processing and Nottingham scale. The developed system is composed of 4 parts; measurement part, image processing part, computational part, facial palsy evaluation & display part. Two web cam were used to get images. The 8 marker on face were recognized at image processing part. The absolute three dimensional positions of markers were calculated at computational part. Finally, Nottingham scale was calculated and displayed at facial palsy evaluation & display part. The effects of measurement method and position of subject on Nottingham scale were tested. The markers were measured with 2-dimension and 3-dimension. The subject was look at the camera with $0^{\circ}$ and $11^{\circ}$ rotation. The change of Scale was large in the case of $11^{\circ}$ rotation with 2-dimension measurement. So, the developed system with 3-dimension measurement is robust to the orientation change of subject. The developed system showed the robustness of grading error originated from subject posture.

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