• 제목/요약/키워드: measurement scale

검색결과 2,641건 처리시간 0.035초

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
    • /
    • 제20권6호
    • /
    • pp.719-737
    • /
    • 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
    • /
    • 제32권2호
    • /
    • pp.143-159
    • /
    • 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.

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

  • 김건엽;감신;이상원;박기수;채성철;천병렬
    • Journal of Preventive Medicine and Public Health
    • /
    • 제38권1호
    • /
    • pp.61-70
    • /
    • 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.

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

  • 신승우;정석희;이종수;신현대;김성수
    • 동국한의학연구소논문집
    • /
    • 제8권2호
    • /
    • pp.25-46
    • /
    • 2000
  • 통증은 환자들로 하여금 내원하게 하는 주된 증상중의 하나로, 치료방법의 선택 및 효과 판정을 위해서는 적절한 평가가 필요하다. 통증은 실험적인 방법과 임상적인 방법에 의해 측정될 수 있는데, 통증의 주관적인 성격상 임상적인 방법이 일반적으로 사용된다. 통증의 임상적측정법은 일차원적측정법과 다차원적측정법으로 대별할 수 있는데, 일차원적 측정법으로는 시각적상사척도(Visual Analogue Scale), 구술적평정척도(Verbal Rating Scale), 수치평정척도(Numerical Rating Scale), 통증표정척도(Pain Faces Scale), 그리고 포커칩 도구(Poker Chip Tool)등이 있고, 다차원적 측정법으로는 McGill 동통질문서(McGill Pain Questionnaire), 다면적인성검사(MMPI), 통증행동척도(Pain Behavior Scale), 통증장애지표(Pain Disability Index), 그리고 통증평정척도(Pain Raing Scale)등이 있다. 일차원적 측정법은 주로 환자의 자가통증평가법에 기초하여 통증의 강도를 측정하는데, 측정방법의 단순함과 신속성으로 인해 급성통증을 평가하는데 주로 사용된다. 다차원적인 측정법은 통증의 주관적, 정신적 그리고 행동적인 면을 측정하는데, 측정방법이 포괄적이고 신뢰성이 있어서 만성통증을 측정하는데 사용된다. 환자의 언어와 인지능력은 정확한 통증을 평가하는데 장애가 되는 주된 요인이다. 통증에 따른 행동반응이나 생체반응은 환자의 통증을 완전히 대변하지 못하지만 이러한 상황에 있어 유용한 통증평가지표가 될 수 있다. 통증평가법을 결정할 때에는 먼저 측정하려고 하는 통증의 성격을 고려하여 어떠한 면을 측정할 것인가를 결정해야하며 아울러 환자의 언어와 인지능력을 고려해야 한다. 적절한 평가법의 선택은 환자의 진단과 치료에 있어 유효한 결론에 이르게 하는 중요한 과정이다.

  • PDF

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

  • 박재실;석창성
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2003년도 춘계학술대회
    • /
    • pp.397-402
    • /
    • 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.

  • PDF

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

  • Heo, Sunyeong;Chang, Duk-Joon
    • 통합자연과학논문집
    • /
    • 제5권3호
    • /
    • pp.157-162
    • /
    • 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.

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

  • 김세희;이은영
    • 한국의류학회지
    • /
    • 제29권3_4호
    • /
    • pp.491-501
    • /
    • 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.

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

  • 최자윤
    • 한국간호교육학회지
    • /
    • 제9권1호
    • /
    • pp.136-143
    • /
    • 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.

  • PDF

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
    • /
    • 제19권4호
    • /
    • pp.1123-1131
    • /
    • 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.

  • PDF

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

  • 장민;신상훈
    • 재활복지공학회논문지
    • /
    • 제9권2호
    • /
    • pp.129-135
    • /
    • 2015
  • 본 연구에서는 3차원 영상처리와 노팅험 스케일을 이용하여 안면마비 평가 시스템을 개발하였다. 시스템은 측정부, 영상처리부, 연산부, 그리고 안면마비 평가 및 출력부로 구성되어 있다. 두 개의 웹캠을 사용하여 안면부의 8곳에 부착된 마커의 3차원 위치를 계산하였으며, 이를 이용하여 노팅험 스케일을 계산하고 화면에 보여준다. 피험자의 자세변화와 측정방식이 노팅험 스케일에 미치는 영향을 조사하였다. 측정방식은 2차원과 3차원을 비교하였으며, 피험자자세는 정면응시와 $11^{\circ}$ 측면응시를 비교하였다. 측면응시한 피험자를 2차원 방식으로 측정한 경우의 오차가 가장 컸다. 3차원 측정방식이 피험자의 자세변화에 따른 오차에 가장 덜 민감하였다.

  • PDF