• 제목/요약/키워드: quantification technique

검색결과 216건 처리시간 0.028초

원자력발전소의 정량적인 안전 해석을 위한 사건수목 기법의 응용 (Application of Event Tree Technique for Quantification of Nuclear Power Plant Safety)

  • 김시달;진영호;김동하;박수용;박종화
    • 한국안전학회지
    • /
    • 제15권2호
    • /
    • pp.126-135
    • /
    • 2000
  • Probabilistic Safety Assessment (PSA) is an engineering analysis method to identify possible contributors to the risk from a nuclear power plant and now it has become a standard tool in safety evaluation of nuclear power plants. PSA consists of three phases named as Level 1, 2 and 3. Level 2 PSA, mainly focused in this paper, uses a step-wise approach. At first, plant damage states (PDSs) are defined from the Level 1 PSA results and they are quantified. Containment event tree (CET) is then constructed considering the physico-chemical phenomena in the containment. The quantification of CET can be assisted by a decomposition event tree (DET). Finally, source terms are quantitatively characterized by the containment failure mode. As the main benefit of PSA is to provide insights into plant design, performance and environmental impacts, including the identification of the dominant risk contributors and the comparison of options for reducing risk, this technique is expected to be applied to the industrial safety area.

  • PDF

Graphical Representation of Partially Ranked Data

  • Han, Sang-Tae
    • Communications for Statistical Applications and Methods
    • /
    • 제18권5호
    • /
    • pp.637-644
    • /
    • 2011
  • Partially ranked data refers to the situation in which there are p distinct objects; however each judge specifies only first s (s < p) choices. The group theoretic formulation for partially ranked data analysis was set up by Critchlow (1985). We propose a graphical method for partially ranked data by quantifying objects and judges. In a plot for judges, the interpoint distances can be interpreted as Spearman or Kendall distances between two rankings given by respective judges. Similarly, we also construct a plot for objects with a sensible relationship to the previous plot for judges. This study extends the Han and Huh (1995) quantification method of fully ranked data using Gabriel's (1971) biplot technique for multivariate data matrix.

확률론적 기법을 이용한 시변 가용송전용량 결정 (Probabilistic Approach to Time Varying Available Transfer Capability Calculation)

  • 신동준;김규호;김진오
    • 대한전기학회논문지:전력기술부문A
    • /
    • 제54권11호
    • /
    • pp.533-539
    • /
    • 2005
  • According to NERC definition, Available Transfer Capability (ATC) is a measure of the transfer capability remaining in the physical transmission network for the future commercial activity. To calculate Available Transfer Capability, accurate and defensible Total Transfer Capability, Capacity Benefit Margin and Transmission Reliability Margin should be calculated in advance. This paper proposes a method to quantify time varying Available Transfer Capability based on probabilistic approach. The uncertainties of power system and market are considered as complex random variables. Total Transfer Capability is determined by optimization technique such as SQP(Sequential Quadratic Programming). Transmission Reliability Margin with the desired probabilistic margin is calculated based on Probabilistic Load Flow analysis, and Capacity Benefit Margin is evaluated using LOLE of the system. Suggested Available Transfer Capability quantification method is verified using IEEE RTS with 72 bus. The proposed method shows efficiency and flexibility for the quantification of Available Transfer Capability.

Multi-constrained optimization combining ARMAX with differential search for damage assessment

  • K, Lakshmi;A, Rama Mohan Rao
    • Structural Engineering and Mechanics
    • /
    • 제72권6호
    • /
    • pp.689-712
    • /
    • 2019
  • Time-series models like AR-ARX and ARMAX, provide a robust way to capture the dynamic properties of structures, and their residuals can be effectively used as features for damage detection. Even though several research papers discuss the implementation of AR-ARX and ARMAX models for damage diagnosis, they are basically been exploited so far for detecting the time instant of damage and also the spatial location of the damage. However, the inverse problem associated with damage quantification i.e. extent of damage using time series models is not been reported in the literature. In this paper, an approach to detect the extent of damage by combining the ARMAX model by formulating the inverse problem as a multi-constrained optimization problem and solving using a newly developed hybrid adaptive differential search with dynamic interaction is presented. The proposed variant of the differential search technique employs small multiple populations which perform the search independently and exchange the information with the dynamic neighborhood. The adaptive features and local search ability features are built into the algorithm in order to improve the convergence characteristics and also the overall performance of the technique. The multi-constrained optimization formulations of the inverse problem, associated with damage quantification using time series models, attempted here for the first time, can considerably improve the robustness of the search process. Numerical simulation studies have been carried out by considering three numerical examples to demonstrate the effectiveness of the proposed technique in robustly identifying the extent of the damage. Issues related to modeling errors and also measurement noise are also addressed in this paper.

필터 기반 블랙카본 측정에서의 보정과 불확실성에 대한 고찰 (Corrections and Artifacts Regarding Filter-based Measurements of Black Carbon)

  • 이정훈
    • 한국대기환경학회지
    • /
    • 제34권4호
    • /
    • pp.610-615
    • /
    • 2018
  • A filter-based optical technique is one of the representative ways for the measurement and quantification of black carbon (BC). Since the filter-based technique adopts a simple principle, it is easy to put into practical use and instrumental products have already been commercialized. In this study, however, the absorption coefficients of BC after the correction process was estimated to be approximately 3 times lower than those before the correction process. In addition, the difference between before and after corrections was also evident for the trend of increasing and decreasing absorption coefficient. When BC concentration is low, uncertainty may increase regardless of corrections due to the artifacts of filter. In this sense, techniques without using a filter are required, and uncertainties will be minimized if these techniques are used to further complement the filter-based black carbon measurements. Finally, this study is believed to help understand the uncertainty and correction of filter-based black carbon measurements.

The Fundamental Requirements in the Application of Relaxed Eddy Accumulation Method for Measuring the Trace Gas Fluxes

  • Kim Ki-Hyun
    • Journal of Korean Society for Atmospheric Environment
    • /
    • 제21권E1호
    • /
    • pp.37-39
    • /
    • 2005
  • It is well perceived that micrometeorological approach is one of the most reliable method for the quantification of vertical fluxes of trace components in the atmosphere. In this study, the feasibility of relaxed eddy accumulation (REA) method is discussed with respect to its reliability in the field application. Knowing that the use of micrometeorological approaches requires validation of analytical uncertainties involved, the problems and issues associated with its application are discussed to stimulate the proper employment of such technique in the field study.

Analysis of Whole Transcriptome Sequencing Data: Workflow and Software

  • Yang, In Seok;Kim, Sangwoo
    • Genomics & Informatics
    • /
    • 제13권4호
    • /
    • pp.119-125
    • /
    • 2015
  • RNA is a polymeric molecule implicated in various biological processes, such as the coding, decoding, regulation, and expression of genes. Numerous studies have examined RNA features using whole transcriptome sequencing (RNA-seq) approaches. RNA-seq is a powerful technique for characterizing and quantifying the transcriptome and accelerates the development of bioinformatics software. In this review, we introduce routine RNA-seq workflow together with related software, focusing particularly on transcriptome reconstruction and expression quantification.

컴퓨터 비젼에 의한 공구마모의 자동계측 (The Automated Measurement of Tool Wear using Computer Vision)

  • 송준엽;이재종;박화영
    • 한국기계연구소 소보
    • /
    • 통권19호
    • /
    • pp.69-79
    • /
    • 1989
  • Cutting tool life monitoring is a critical element needed for designing unmanned machining systems. This paper describes a tool wear measurement system using computer vision which repeatedly measures flank and crater wear of a single point cutting tool. This direct tool wear measurement method is based on an interactive procedure utilizing a image processor and multi-vision sensors. A measurement software calcultes 7 parameters to characterize flank and crater wear. Performance test revealed that the computer vision technique provides precise, absolute tool-wear quantification and reduces human maesurement errors.

  • PDF

Deconvolution 분석(分析)을 이용(利用)한 좌우단락량(左右短絡量) 측정(測定)의 의의(意義) (Radionuclide Quantitation of Left-to-Right Cardiac Shunts Using Deconvolution Analysis)

  • 오연상;이명철;조보연;고창순
    • 대한핵의학회지
    • /
    • 제18권1호
    • /
    • pp.9-17
    • /
    • 1984
  • The purpose of this study is to investigate significance of new method for quantification of left to right cardiac shunts using deconvolution analysis as an adjunct to gamma variate analysis in patients with bad bolus injection. In the present study, quantitative radionuclide angiocardiography (QRAC) was performed with and without deconvolution analysis (DA) in 37 patients with left to right shunt and 103 control patients without shunt. The results obtained were as follows; 1) The mean value of $Q_p/Q_s$ in 103 control patients was $1.10{\pm}0.12$ without DA, and was $1.01{\pm}0.03$ with DA. 2) Correlation(r) between oximetry and QRAC with DA was 0.87 and correlation(r) between oximetry and QRAC without DA was 0.61. 3) The 13 patients with left to right shunt, whose $Q_p/Q_s$ was greater than 3.0 by QRAC without DA, was studied by DA. Then the $Q_p/Q_s$ values were measurable in these 13 patients by DA and they showed significant correlation with oximetry. (r=0.68) The results indicate that deconvolution analysis technique for quantification of a left to right shunt provides more reliable and accurate shunt quantification, and reduces the influences of poor bolus injection.

  • PDF