• Title/Summary/Keyword: Measurement and assessment

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Risk identification, assessment and monitoring design of high cutting loess slope in heavy haul railway

  • Zhang, Qian;Gao, Yang;Zhang, Hai-xia;Xu, Fei;Li, Feng
    • Structural Monitoring and Maintenance
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    • v.5 no.1
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    • pp.67-78
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    • 2018
  • The stability of cutting slope influences the safety of railway operation, and how to identify the stability of the slope quickly and determine the rational monitoring plan is a pressing problem at present. In this study, the attribute recognition model of risk assessment for high cutting slope stability in the heavy haul railway is established based on attribute mathematics theory, followed by the consequent monitoring scheme design. Firstly, based on comprehensive analysis on the risk factors of heavy haul railway loess slope, collapsibility, tectonic feature, slope shape, rainfall, vegetation conditions, train speed are selected as the indexes of the risk assessment, and the grading criteria of each index is established. Meanwhile, the weights of the assessment indexes are determined by AHP judgment matrix. Secondly, The attribute measurement functions are given to compute attribute measurement of single index and synthetic attribute, and the attribute recognition model was used to assess the risk of a typical heavy haul railway loess slope, Finally, according to the risk assessment results, the monitoring content and method of this loess slope were determined to avoid geological disasters and ensure the security of the railway infrastructure. This attribute identification- risk assessment- monitoring design mode could provide an effective way for the risk assessment and control of heavy haul railway in the loess plateau.

A Study on Technical Measures and their Application (기술척도 적용 연구)

  • Choi, Seok
    • Journal of the Korean Society of Systems Engineering
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    • v.3 no.2
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    • pp.3-8
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    • 2007
  • Technical Measures includes Measures of Effectiveness(MOEs), Key Performance Parameters(KPPs), Measures of Performance(MOPs) and/or Technical Performance Measures(TPMs). Technical measurement is the set of measurement activities used to provide supplier and/ or acquirer insight into progress in the definition and development of the technical solution, ongoing assessment of the associated risks and issues. This paper describes how technical measures can be applied, using the measurement process described in the previous study and shows the relationship between the various types of technical measures.

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A Laboratory Study on Low Frequency Noise Assessment based on Noise Acceptability Limit (소음 수응 한계를 고려한 저주파 소음평가에 대한 실험적 연구)

  • Hong, Seung-Ki;Kim, Jae-Hwan;Kim, Kyu-Tae;Lee, Soo-Gab
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.17 no.8
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    • pp.736-740
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    • 2007
  • A laboratory study on low frequency noise assessment has been carried out to evaluate the relevance of the weighting curve. Especially, the A-weighting curve which is used in most noise assessments has been evaluated using the acceptability limit in this study. The acceptability limit is one of the indicators in which the subjective responses were well-reflected. For the measurement of the acceptability limit, pure tone stimuli were used in the frequency range between 20 and 200 Hz. The measurement was proceeded in the anechoic chamber to minimize the background noise level. A total of 29 test subjects, who were aged between 19 to 33 years, participated in this study. They had been exposed to various stimuli for about 1 hour by supra-aural earphone. The measurement consisted of two listening sessions: hearing threshold and the acceptability limit session. The results showed that the tendency of the acceptability limit curve was approximately equal to C-weighting curve which had been found to be superior to A-weighting curve in assessment of low frequencies.

Elementary School Teachers' and Preservice Elementary School Teachers' Actual and Preferred Types of Science Assessment (초등교사와 예비초등교사의 과학평가 실태와 지향)

  • Lee, Haemin;Kang, Sukjin
    • Journal of Korean Elementary Science Education
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    • v.39 no.1
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    • pp.15-25
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    • 2020
  • In this study, we investigated elementary and preservice elementary school teachers' actual and preferred types of science assessment focusing on the purpose and the method of assessment. Participants were 75 elementary school teachers and 93 preservice elementary school teachers. The questionnaire adopted from previous relevant studies was administerd in order to examine the types of assessment which the teachers have actually implemented and the preferred types of assessment for hypothetical situations known as the prototypical examples of constructivist assessment. The results revealed that most teachers and preservice teachers tend to possess the summative-oriented purpose of assessment. An affective assessment purpose focused on evaluating students' interest, attitude, and curiosity toward science was newly identified in this study. In analyzing teachers' responses from the viewpoint of the method of science assessment, responses of an informal mode such as observation and portfolio were noticeable. However, most of them were found to correspond to the traditional summative-oriented purpose of assessment. For prototypical constuctivist assessment situations, teachers and preservice teachers were found to prefer the performance and the informal modes than the measurement mode of the assessment methods, whereas their purposes of the assessment were not found to be constructivist.

A Synthetic Human Sensibility Assessment System based on Psycho-physiological Evaluation (심리·생리 평가를 기반으로 한 통합 감성평가 시스템)

  • Chung, Soon-Cheol;Tack, Gye-Rae;Yi, Jeong-Han;Min, Byung-Chan
    • Journal of Korean Institute of Industrial Engineers
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    • v.31 no.2
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    • pp.127-134
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    • 2005
  • Human sensibility is assessed by measuring and analyzing various physiological signals in an objective way, or by analyzing adjectives chosen by the subjects in a subjective way. The present study aims at developing an integrated human sensibility assessment system that measures changes in a person's objective and subjective sensibility in real-time and analyzes them in an integrative way. The present system is composed of a real-time subjective sensibility assessment system, an automatic subjective sensibility assessment system and a real-time physiological signal measurement and analysis system for sensibility assessment, which are separated from one another. It can be utilized individually, or can be combined as a synthetic sensibility assessment system for comprehensive sensibility assessment.

Accurate Camera Self-Calibration based on Image Quality Assessment

  • Fayyaz, Rabia;Rhee, Eun Joo
    • Journal of Information Technology Applications and Management
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    • v.25 no.2
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    • pp.41-52
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    • 2018
  • This paper presents a method for accurate camera self-calibration based on SIFT Feature Detection and image quality assessment. We performed image quality assessment to select high quality images for the camera self-calibration process. We defined high quality images as those that contain little or no blur, and have maximum contrast among images captured within a short period. The image quality assessment includes blur detection and contrast assessment. Blur detection is based on the statistical analysis of energy and standard deviation of high frequency components of the images using Discrete Cosine Transform. Contrast assessment is based on contrast measurement and selection of the high contrast images among some images captured in a short period. Experimental results show little or no distortion in the perspective view of the images. Thus, the suggested method achieves camera self-calibration accuracy of approximately 93%.

Selection of Measuring Sensors for Reactor Vessel Internals Comprehensive Vibration Assessment Program in Advanced Power Reactor 1400 (APR1400 원자로 내부구조물 종합진동평가 측정센서 선정)

  • Ko, Do-Young;Lee, Jae-Gon
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2010.10a
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    • pp.433-438
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    • 2010
  • Reactor vessel internals comprehensive vibration assessment program(RVI CVAP) is one of the necessary tests to ensure the safety of nuclear power plants. RVI CVAP of U.S. Nuclear Regulatory Commission Regulatory Guide 1.20(U.S. NRC R.G. 1.20) consists of the analysis, measurement, and inspection. One of the core technologies of the measurement program for RVI CVAP is to select suitable sensors. We analyzed RVI design data of Palo Verde nuclear generating station(U.S.) and Yonggwang nuclear generating station(Korea) and investigated measuring sensors used in both of them; moreover, we investigated sensors used for measurement of RVI CVAP for the last 20 years throughout the world. Based on these results, we selected the most suitable sensors for RVI CVAP in Advanced Power Reactor 1400(APR1400).

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Developing Sample Sentences for Voice Assessment of Koreans: A Preliminary Study (한국인을 위한 음도진단용 표준문장개발연구: 예비측정 및 분석결과)

  • Kim Soo-Jin;Moon Seung-Jae;Shin Jiyoung
    • Proceedings of the KSPS conference
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    • 2003.05a
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    • pp.109-112
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    • 2003
  • This paper aims at developing sample paragraphs for voice pitch assessment which is specifically designed for Koreans. Recently the demand for such a battery of sample sentences has been steadily increased among Korean speech therapists. In this paper, different sample paragraphs (two conventionally used paragraphs and three newly developed ones which consist mainly of sonorant sounds and different types of sentences), different softwares (Dr. Speech, Wavesurfer, Praat) and different techniques (automatic measurement and detailed measurement in which the researcher controls many aspects which might influence the measurement of pitch) will be compared for measuring fundamental frequency.

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Exposure Assessment in Risk Assessment

  • Herrick Robert F.
    • 대한예방의학회:학술대회논문집
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    • 1994.02a
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    • pp.426-430
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    • 1994
  • The assessment of exposure is an important component of the risk assessment process. Exposure information is used in risk assessment in at least two ways: 1) in the identification of hazards and the epidemiologic research investigating exposure-response relationships and 2) in the development of population exposure estimates. In both of these cases, the value of a chemical risk assessment is enhanced by improvements in the quality of exposure assessments. The optimum exposure assessment is the direct measurement of population exposure; however, such measurements are rarely available. Recent developments in methods for exposure assessment allow estimates to be made that are valid representations of actual exposure. The use of these exposure estimates to classify exposures correctly enhances the likelihood that causal associations between exposure and response will be correctly identified and that population risks will be accurately assessed.

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OWAS and EMG-based Mason's Physical Workload Measurement (OWAS 및 근전도 기반 석공 작업부하 비교연구)

  • Seo, Byoung-Wook;Lim, Tae-Kyung;Lee, Dong-Eun
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2015.05a
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    • pp.194-195
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    • 2015
  • Methods for measuring the physical workload of construction workers are classified into posture assessment techniques (i.e., OWAS, RULA, etc.) and physiological measurement techniques (i.e., EMG, heart rate, etc.). The one does not quantify the workload on a specific body part of a worker by considering the weight of the hand tools or materials on hand and time for holding a particular posture. This paper presents a procedure for evaluating a physical demand using the electromyography (EMG) sensor. This study compares the EMG measurement and the posture assessment. The case study is carried out on a masonry operation.

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