• 제목/요약/키워드: quality parameter

검색결과 1,596건 처리시간 0.031초

QUALITY ASSURANCE IN ROADWAY PAVEMENT CONSTRUCTION

  • Myung Goo Jeong;Younghan Jung
    • 국제학술발표논문집
    • /
    • The 5th International Conference on Construction Engineering and Project Management
    • /
    • pp.596-601
    • /
    • 2013
  • In the current pavement construction practice, the state agencies traditionally determine the quality of the as-constructed pavement mix based on individual mixture material parameters (e.g., air voids, cement or asphalt content, aggregate gradation, etc.) and consider these parameters as key variables to influence payment schedule to the contractors and the present and future quality of the as-constructed mixture. A set of empirically pre-determined pay adjustment schedule for each parameter that was differently developed and being used by the individual agencies is then applied to a given project, in order to judge whether each parameter conforms to the designated specifications and consequently the contractor may either be rewarded or penalized in accordance with the payment schedule. With an improved quality assurance system, the Performance Related Specification, the individual parameters are not utilized as a direct judgment factor; rather, they become independent variables within a performance prediction function which is directly used to predict the performance. The quantified performance based on the prediction model is then applied to evaluate the pavement quality. This paper presents the brief history of the quality assurance in asphalt pavement construction including the Performance Related Specifications, statistical performance models in terms of fatigue and rutting distresses, as an example of the performance prediction models, and envisions the possibilities as to how this Performance Related Specification could be utilized in other infrastructures construction quality assurance.

  • PDF

파라미터 설계에 대한 다중 반응 동시 최적화 대체 방안 (Alternative Methods for Simultaneous Optimization of Multi-Responses in Parameter Design)

  • 박병전;조병엽;권용만
    • 한국품질경영학회:학술대회논문집
    • /
    • 한국품질경영학회 1998년도 The 12th Asia Quality Management Symposium* Total Quality Management for Restoring Competitiveness
    • /
    • pp.123-132
    • /
    • 1998
  • Robust design is an approach to reducing performance variation of quality characteristic values in quality engineering. Taguchi has an idea that mean and variation are handled simultaneously to reduce the expected loss in products. Taguchi parameter design has a great deal of advantages but it also has some disadvantages. The various research efforts aimed at developing alternative methods.

  • PDF

Development of a Quality Assurance Safety Assessment Database for Near Surface Radioactive Waste Disposal

  • Park J.W.;Kim C.L.;Park J.B.;Lee E.Y.;Lee Y.M.;Kang C.H.;Zhou W.;Kozak M.W.
    • Nuclear Engineering and Technology
    • /
    • 제35권6호
    • /
    • pp.556-565
    • /
    • 2003
  • A quality assurance safety assessment database, called QUARK (QUality Assurance Program for Radioactive Waste Management in Korea), has been developed to manage both analysis information and parameter database for safety assessment of low- and intermediate-level radioactive waste (LILW) disposal facility in Korea. QUARK is such a tool that serves QA purposes for managing safety assessment information properly and securely. In QUARK, the information is organized and linked to maximize the integrity of information and traceability. QUARK provides guidance to conduct safety assessment analysis, from scenario generation to result analysis, and provides a window to inspect and trace previous safety assessment analysis and parameter values. QUARK also provides default database for safety assessment staff who construct input data files using SAGE(Safety Assessment Groundwater Evaluation), a safety assessment computer code.

순간수위변화 및 양수시험을 통한 수리상수 추정의 문제점 분석 (Multiple Slug and Pumping Tests for Quality Enhancement of Hydraulic Parameter Estimates)

  • 이진용;이강근;정형재;배광옥
    • 대한지하수환경학회지
    • /
    • 제6권1호
    • /
    • pp.14-22
    • /
    • 1999
  • 순간수위변화 및 양수 시험은 현장에서 대수층의 수리상수 추정을 위해 널리 사용되는 수리시험이다. 그런데 이런 수리시험을 수행하고 그 결과를 해석함에 있어서 다양한 오차 및 불확실성 요인이 있음에도 불구하고 이에 대한 심각한 고려가 많지 않았다. 본 연구에서는 양수 및 순간수위 변화시험을 다수의 동일 관정에서 반복 수행하고 그 결과를 다각적으로 검토함으로써 두 수리시험에 개입될 수 있는 오차 및 불확실성 요인을 분석하였다.

  • PDF

A Coupled Recursive Total Least Squares-Based Online Parameter Estimation for PMSM

  • Wang, Yangding;Xu, Shen;Huang, Hai;Guo, Yiping;Jin, Hai
    • Journal of Electrical Engineering and Technology
    • /
    • 제13권6호
    • /
    • pp.2344-2353
    • /
    • 2018
  • A coupled recursive total least squares (CRTLS) algorithm is proposed for parameter estimation of permanent magnet synchronous machines (PMSMs). TLS considers the errors of both input variables and output ones, and thus achieves more accurate estimates than standard least squares method does. The proposed algorithm consists of two recursive total least squares (RTLS) algorithms for the d-axis subsystem and q-axis subsystem respectively. The incremental singular value decomposition (SVD) for the RTLS obtained by an approximate calculation with less computation. The performance of the CRTLS is demonstrated by simulation and experimental results.

ON PREDCTION OF CONCENTRATION OF LIQUID FOOD BY ACOUSTIC NON-LINEAR PARAMETER B/A

  • Nishizu, Takahisa;Ikeda, Yoshio
    • 한국농업기계학회:학술대회논문집
    • /
    • 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
    • /
    • pp.344-352
    • /
    • 1993
  • The purpose of this study is to investigate the possibility of the non-destructive quality evaluation for food by the acoustic non-linear parameter B/A which is a measure of the non-linearity of the state equation of the medium in terms of pressure and density. The B/A of water, corn oil O/W(oil in water) emulsion and milk were measured by using a sound velocity measuring system. The B/A value of water was measured for ascertaining reliability of our experimental system. Corn oil W/W emulsion was prepared as a model of milk . It was proved that the B/A value of O/W emulsion was related to the oil concentration by a law of mixture. We applied this result to milk and obtained satisfactory results for predicting the milk fat concentration.

  • PDF

Scalable Extension of HEVC for Flexible High-Quality Digital Video Content Services

  • Lee, Hahyun;Kang, Jung Won;Lee, Jinho;Choi, Jin Soo;Kim, Jinwoong;Sim, Donggyu
    • ETRI Journal
    • /
    • 제35권6호
    • /
    • pp.990-1000
    • /
    • 2013
  • This paper describes the scalable extension of High Efficiency Video Coding (HEVC) to provide flexible high-quality digital video content services. The proposed scalable codec is designed on multi-loop decoding architecture to support inter-layer sample prediction and inter-layer motion parameter prediction. Inter-layer sample prediction is enabled by inserting the reconstructed picture of the reference layer (RL) into the decoded picture buffer of the enhancement layer (EL). To reduce the motion parameter redundancies between layers, the motion parameter of the RL is used as one of the candidates in merge mode and motion vector prediction in the EL. The proposed scalable extension can support scalabilities with minimum changes to the HEVC and provide average Bj${\o}$ntegaard delta bitrate gains of about 24% for spatial scalability and of about 21% for SNR scalability compared to simulcast coding with HEVC.

전문가 의견을 고려한 다특성치 파라미터 설계에 관한 연구 (The Parameter Design of Multiple Characteristics with Engineer's Opinions)

  • 조용욱;박명규
    • 품질경영학회지
    • /
    • 제27권2호
    • /
    • pp.218-236
    • /
    • 1999
  • The purpose of parameter design is to determine optimal settings of design parameters of a product or a process such that the performance characteristics of a product exhibit small variabilities around their target values. Taguchi made significant contributions in this area. However, his analysis of the problem focused on only one performance characteristic or response, although in product and process design, multiple characteristics are more common. The critical problem in dealing with multiple characteristics is how to compromise the conflict among the selected levels of the design parameters for each individual characteristic. In this paper, Methodology using SN ratio optimized by univariate technique is proposed and a parameter design procedure to achieve the optimal balance among several different response variables is developed. Existing case studies are solved by the proposed method and the results are compared with ones by the sum of SN ratios, the expected weighted loss, the desirability function, and EXTOPSIS model.

  • PDF

화질 분석을 통한 카메라 문서 영상의 적응적 이진화 (An Adaptive Binarization of Camera Document Image by Image Quality Estimation)

  • 김인중
    • 한국정보과학회논문지:소프트웨어및응용
    • /
    • 제34권9호
    • /
    • pp.797-803
    • /
    • 2007
  • 카메라 기반 문서 인식을 위해서는 화질 변화에 적응할 수 있는 이진화 기술이 매우 중요하다. 본 논문에서는 화질 분석을 통해 다양한 화질의 카메라 영상에 효과적으로 적응할 수 있는 이진화 방법을 제안한다. 먼저 이진화 파라미터가 이진화 결과에 미치는 영향을 분석하고, 카메라 영상의 화질을 측정하는 방법을 제안한다. 그리고, 측정된 화질과 이진화 파라미터간의 상관 관계를 통계적으로 분석하여 반영함으로써 화질 변화에 자동으로 적응하는 이진화 방법을 제안한다. 실험을 통해 화질과 이진화 파라미터간에는 유의한 상관 관계가 있으며, 제안하는 방법이 화질에 따라 적절한 파라미터를 추정함으로써 화질변화에 적응함을 확인하였다.

무구속적 방법으로 측정된 심전도의 신뢰도 판별 (Quality Level Classification of ECG Measured using Non-Constraint Approach)

  • 김윤재;허정;박광석;김성완
    • 대한의용생체공학회:의공학회지
    • /
    • 제37권5호
    • /
    • pp.161-167
    • /
    • 2016
  • Recent technological advances in sensor fabrication and bio-signal processing enabled non-constraint and non-intrusive measurement of human bio-signals. Especially, non-constraint measurement of ECG makes it available to estimate various human health parameters such as heart rate. Additionally, non-constraint ECG measurement of wheelchair user provides real-time health parameter information for emergency response. For accurate emergency response with low false alarm rate, it is necessary to discriminate quality levels of ECG measured using non-constraint approach. Health parameters acquired from low quality ECG results in inaccurate information. Thus, in this study, a machine learning based approach for three-class classification of ECG quality level is suggested. Three sensors are embedded in the back seat, chest belt, and handle of automatic wheelchair. For the two sensors embedded in back seat and chest belt, capacitively coupled electrodes were used. The accuracy of quality level classification was estimated using Monte Carlo cross validation. The proposed approach demonstrated accuracy of 94.01%, 95.57%, and 96.94% for each channel of three sensors. Furthermore, the implemented algorithm enables classification of user posture by detection of contacted electrodes. The accuracy for posture estimation was 94.57%. The proposed algorithm will contribute to non-constraint and robust estimation of health parameter of wheelchair users.