• Title/Summary/Keyword: Quantitative parameters

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Sensitivity and Uncertainty Analysis of Two-Compartment Model for the Indoor Radon Pollution (실내 라돈오염 해석을 위한 2구역 모델의 민감도 및 불확실성 분석)

  • 유동한;이한수;김상준;양지원
    • Journal of Korean Society for Atmospheric Environment
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    • v.18 no.4
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    • pp.327-334
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    • 2002
  • The work presents sensitivity and uncertainty analysis of 2-compartment model for the evaluation of indoor radon pollution in a house. Effort on the development of such model is directed towards the prediction of the generation and transfer of radon in indoor air released from groundwater. The model is used to estimate a quantitative daily human exposure through inhalation of such radon based on exposure scenarios. However, prediction from the model has uncertainty propagated from uncertainties in model parameters. In order to assess how model predictions are affected by the uncertainties of model inputs, the study performs a quantitative uncertainty analysis in conjunction with the developed model. An importance analysis is performed to rank input parameters with respect to their contribution to model prediction based on the uncertainty analysis. The results obtained from this study would be used to the evaluation of human risk by inhalation associated with the indoor pollution by radon released from groundwater.

A Statistical Approach to Analysis of Saccadic Eye Movements (Saccadic 안구운동 해석에 대한 통계학적인 접근)

  • Kim, Nam-Gyun;Kim, Bu-Gil
    • Journal of Biomedical Engineering Research
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    • v.10 no.3
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    • pp.289-292
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    • 1989
  • In this study we propose an approach based on statistical method which use the whole of saccades instead of using a few points of saccades in the quantitative analyse saccades. We computed statistical parameters such as mean velocity, quadratic mean velocity, standard duration, skewness of saccades velocity, flattness factor of saccades velocity, and mean delay by considering eye velocity as a probability density function. The results abtained are the following as ; This parameters showed the same trend like that of the main sequence. They were not biased by the systematic errors due to the arbitrary threshold. They were also less sensitive to noise, which was tested through the model simulation. So they are expected to provide a more comprehensive quantitative description of the dynamic properties of saccade in the diagnostic field.

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A Quantitative Model for the Projection of Health Expenditure (의료비 결정요인 분석을 위한 계량적 모형 고안)

  • Kim, Han-Joong;Lee, Young-Doo;Nam, Chung-Mo
    • Journal of Preventive Medicine and Public Health
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    • v.24 no.1 s.33
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    • pp.29-36
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    • 1991
  • A multiple regression analysis using ordinary least square (OLS) is frequently used for the projection of health expenditure as well as for the identification of factors affecting health care costs. Data for the analysis often have mixed characteristics of time series and cross section. Parameters as a result of OLS estimation, in this case, are no longer the best linear unbiased estimators (BLUE) because the data do not satisfy basic assumptions of regression analysis. The study theoretically examined statistical problems induced when OLS estimation was applied with the time series cross section data. Then both the OLS regression and time series cross section regression (TSCS regression) were applied to the same empirical da. Finally, the difference in parameters between the two estimations were explained through residual analysis.

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Quantitative Evaluation Method for Etch Sidewall Profile of Through-Silicon Vias (TSVs)

  • Son, Seung-Nam;Hong, Sang Jeen
    • ETRI Journal
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    • v.36 no.4
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    • pp.617-624
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    • 2014
  • Through-silicon via (TSV) technology provides much of the benefits seen in advanced packaging, such as three-dimensional integrated circuits and 3D packaging, with shorter interconnection paths for homo- and heterogeneous device integration. In TSV, a destructive cross-sectional analysis of an image from a scanning electron microscope is the most frequently used method for quality control purposes. We propose a quantitative evaluation method for TSV etch profiles whereby we consider sidewall angle, curvature profile, undercut, and scallop. A weighted sum of the four evaluated parameters, nominally total score (TS), is suggested for the numerical evaluation of an individual TSV profile. Uniformity, defined by the ratio of the standard deviation and average of the parameters that comprise TS, is suggested for the evaluation of wafer-to-wafer variation in volume manufacturing.

A Study on Picture Quality Impairing Factors and Evaulation Method for The Video Signal in Urban Mobile Reception (영상신호의 시가지 이동수신에 의한 화상열화요인의 평가법에 관한 연구)

  • Deock Ho Ha
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.30A no.3
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    • pp.52-60
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    • 1993
  • Fluttering ghost which is the most severs picture impairment in mobile TV reception under multipath fading environments can be detected by measuring the dynamic variation of the synchronizing pulse timing. And also, the occurrence-stucture of fluttering ghost are directly correlated with the multipath parameters. This paper describes the quantitative evaluating method of the mobile TV pictures impaired by multipath parameters by means of the spectral analysis of synchronizing timing fluctuation. The ghost-flutter curve derived from the spatial amplitue spectrum of synchronizing pulse timing fluctuation express well the spatial variation characteristic, and it has been found to be the quantitative evaluating measure of picture impairment in mobile reception. A correspondence between the ghost-flutter curve (and/or index) and picture quality opinion test results is established.

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A Study on the Application of Interpolation and Terrain Classification for Accuracy Improvement of Digital Elevation Model (수지표고지형의 정확도 향상을 위한 지형의 분류와 보간법의 상용에 관한 연구)

  • 문두열
    • Journal of Ocean Engineering and Technology
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    • v.8 no.2
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    • pp.64-79
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    • 1994
  • In this study, terrain classification, which was done by using the quantitative classification parameters and suitable interpolation method was applied to improve the accuracy of digital elevation models, and to increase its practical use of aerial photogrammetry. A terrain area was classified into three groups using the quantitative classification parameters to the ratio of horizontal, inclined area, magnitude of harmonic vectors, deviation of vector, the number of breakline and proposed the suitable interpolation. Also, the accuracy of digital elevation models was improved in case of large grid intervals by applying combined interpolation suitable for each terrain group. As a result of this study, I have an algorithm to perform the classification of the topography in the area of interest objectively and decided optimal data interpolation scheme for given topography.

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Linearized Methods for Quantitative Analysis and Parametric Mapping of Brain PET (뇌 PET 영상 정량화 및 파라메터영상 구성을 위한 선형분석기법)

  • Kim, Su-Jin;Lee, Jae-Sung
    • Nuclear Medicine and Molecular Imaging
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    • v.41 no.2
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    • pp.78-84
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    • 2007
  • Quantitative analysis of dynamic brain PET data using a tracer kinetic modeling has played important roles in the investigation of functional and molecular basis of various brain diseases. Parametric imaging of the kinetic parameters (voxel-wise representation of the estimated parameters) has several advantages over the conventional approaches using region of interest (ROI). Therefore, several strategies have been suggested to generate the parametric images with a minimal bias and variability in the parameter estimation. In this paper, we will review the several approaches for parametric imaging with linearized methods which include graphical analysis and mulilinear regression analysis.

A Method for Quantitative Performance Evaluation of Edge Detection Algorithms Depending on Chosen Parameters that Influence the Performance of Edge Detection (경계선 검출 성능에 영향을 주는 변수 변화에 따른 경계선 검출 알고리듬 성능의 정량적인 평가 방법)

  • 양희성;김유호;한정현;이은석;이준호
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.25 no.6B
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    • pp.993-1001
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    • 2000
  • This research features a method that quantitatively evaluates the performance of edge detection algorithms. Contrary to conventional methods that evaluate the performance of edge detection as a function of the amount of noise added to he input image, the proposed method is capable of assessing the performance of edge detection algorithms based on chosen parameters that influence the performance of edge detection. We have proposed a quantitative measure, called average performance index, that compares the average performance of different edge detection algorithms. We have applied the method to the commonly used edge detectors, Sobel, LOG(Laplacian of Gaussian), and Canny edge detectors for noisy images that contain straight line edges and curved line edges. Two kinds of noises i.e, Gaussian and impulse noises, are used. Experimental results show that our method of quantitatively evaluating the performance of edge detection algorithms can facilitate the selection of the optimal dge detection algorithm for a given task.

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Dynamic fracture instability in brittle materials: Insights from DEM simulations

  • Kou, Miaomiao;Han, Dongchen;Xiao, Congcong;Wang, Yunteng
    • Structural Engineering and Mechanics
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    • v.71 no.1
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    • pp.65-75
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    • 2019
  • In this article, the dynamic fracture instability characteristics, including dynamic crack propagation and crack branching, in PMMA brittle solids under dynamic loading are investigated using the discrete element method (DEM) simulations. The microscopic parameters in DEM are first calibrated using the comparison with the previous experimental results not only in the field of qualitative analysis, but also in the field of quantitative analysis. The calibrating process illustrates that the selected microscopic parameters in DEM are suitable to effectively and accurately simulate dynamic fracture process in PMMA brittle solids subjected to dynamic loads. The typical dynamic fracture behaviors of solids under dynamic loading are then reproduced by DEM. Compared with the previous experimental and numerical results, the present numerical results are in good agreement with the existing ones not only in the field of qualitative analysis, but also in the field of quantitative analysis. Furthermore, effects of dynamic loading magnitude, offset distance of the initial crack and initial crack length on dynamic fracture behaviors are numerically discussed.

A Study on the Quantification Error due to the Reconstruction Filters in Single Photon Emission Computed Tomography(SPECT) (단일광자방출 전산화단층촬영상에서 재구성 필터에 의한 정량화 오차에 관한 연구)

  • 곽철은;정준기
    • Journal of Biomedical Engineering Research
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    • v.12 no.1
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    • pp.43-48
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    • 1991
  • As the computerized methods and equipments In nuclear medicine imaging increases, quantitative information is needed on the single photon emission computed tomographic Images as well as on the conventional nuclear medicine images. In this paper, the authors investigated the effect of several clinician - friendly reconstrution filters on the resultant transverse slices of backprojected Profiles of radioisotope distribution from the Quantitative point of view, and reduced the filter parameters such as cutoff frequency and order of filter which are neces mary to minimize the quantification error using computer-generated phantoms.

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