• Title/Summary/Keyword: Quantitative parameters

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Detecting of Proximal Caries in Primary Molars using Pen-type QLF Device (펜-타입 QLF 장비의 임상적 유구치 인접면 우식 탐지 성능)

  • Cho, Hyejin;Kim, Hyuntae;Song, Ji-Soo;Shin, Teo Jeon;Kim, Jung-Wook;Jang, Ki-Taeg;Kim, Young-Jae
    • Journal of the korean academy of Pediatric Dentistry
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    • v.48 no.4
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    • pp.405-413
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    • 2021
  • The purpose of this in vivo study was to assess the clinical screening performance of a quantitative light-induced fluorescence (QLF) device in detecting proximal caries in primary molars. Fluorescence loss, red autofluorescence and a simplified QLF score for proximal caries (QS-proximal) were evaluated for their validity in detecting proximal caries in primary molars compared to bitewing radiography. Three hundred and forty-four primary molar surfaces were included in the study. Carious lesions were scored according to lesion severity assessed by visual-tactile and radiographic examinations. The QLF images were analyzed for two quantitative parameters, fluorescence loss and red autofluorescence, as well as for QS-proximal. For both quantitative parameters and QS-proximal, the sensitivity, specificity and area under receiver operating curve (AUROC) were calculated as a function of the radiographic scoring index at enamel and dentin caries levels. Both quantitative parameters showed fair AUROC values for detecting dentine level caries (△F = 0.794, △R = 0.750). QS-proximal showed higher AUROC values (0.757 - 0.769) than that of visual-tactile scores (0.653) in detecting dentine level caries. The QLF device showed fair screening performance in detecting proximal caries in primary molars compared to bitewing radiography.

Analysis of Rock Slope Stability by Using GIS in Mt. Keumsu Area (지구정보시스템을 이용한 금수산일대의 암반사면 안정성 평가)

  • 배현철
    • Economic and Environmental Geology
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    • v.33 no.1
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    • pp.77-88
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    • 2000
  • The goal of this study is to assess the spatial distribution of natural slopes and cutting slopes under would-be development. For this goal, a quantitative slope stability analysis method using GIS integrated with a computer program was developed. Through field investigations, the discontinuity parameters were collected such as orientation of discontinuity, persistence, spacing, JRC, JCS, and water depth. The distributions were interpolated from the ordinary kriging method in ARC/INFO GIS after variogram analysis. The layers showing all parameters needed for limit equilibrium analysis were constructed. The final layer using GIS works composed of 162,352 polygons, that is, unit slopes. The rock slope stability analysis program was coded by C++ language. This program can calculate geometrical vectors related to rock block failures using input orientation data and direction and dimension of strength to occur failure. Also, this can calculate shear strength of joints through empirical equations and quantitative factors of safety. This methodology was applied to the study area which is located in Jaecheon city and Danyang-gun of the northeastern Keumsu is about 135$km^2$. As a result, the study area was entirely stable but unstable, that is, factor of safety less than 1.0dominantly at the slopes near Keumsil, Daejangri, Keumsungmyun and Sojugol, Mt. Dongsan, Juksongmyun by the natural slope stability analysis. Assuming the cutting slope showing the same direction immediate, and quantitative analysis of factors of safety for a regional area could be conducted through GIS integrated with a computer program of limit equilibrium.

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Design of Quantitative Feedback Control System for the Three Axes Hydraulic Road Simulator (3축 유압 도로 시뮬레이터의 정량적 피드백 제어 시스템 설계)

  • Kim, Jin-Wan;Xuan, Dong-Ji;Kim, Young-Bae
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.32 no.3
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    • pp.280-289
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    • 2008
  • This paper presents design of the quantitative feedback control system of the three axes hydraulic road simulator with respect to the dummy wheel for uncertain multiple input-output(MIMO) feedback systems. This simulator has the uncertain parameters such as fluid compressibility, fluid leakage, electrical servo components and nonlinear mechanical connections. This works have reproduced the random input signal to implement the real road vibration's data in the lab. The replaced $m^2$ MISO equivalent control systems satisfied the design specifications of the original $m^*m$ MIMO control system and developed the mathematical method using quantitative feedback theory based on schauder's fixed point theorem. This control system illustrates a tracking performance of the closed-loop controller with low order transfer function G(s) and pre-filter F(s) having the minimum bandwidth for parameters of uncertain plant. The efficacy of the designed controller is verified through the dynamic simulation with combined hydraulic model and Adams simulator model. The Matlab simulation results to connect with Adams simulator model show that the proposed control technique works well under uncertain hydraulic plant system. The designed control system has satisfied robust performance with stability bounds, tracking bounds and disturbance. The Hydraulic road simulator consists of the specimen, hydraulic pump, servo valve, hydraulic actuator and its control equipments

Quantitative analysis of body postural stability (신체자세 안정도의 정량분석에 관한 연구)

  • Cha, E.J.;Kim, K.A.;Lee, T.S.;Lee, K.M.;Kim, N.K.;Kim, Y.H.
    • Proceedings of the KOSOMBE Conference
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    • v.1997 no.11
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    • pp.39-43
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    • 1997
  • Posturography stands or quantitative assessment of body postural stability analysis. The present study developed a balance plate system to monitor patient's center of pressure (COP) movement and to analyze its stability. An equilateral triangular shaped plate was made of duralumin and forces were measured on the three vertices of the plate using industrial load cells. Specially designed electronic circuit picked up force signals ed into data acquisition system to calculate the cartesian coordinates of COP. COP calculation error was less than 2%. The force signals enabled to compute stability measures, which consisted of a variety of clinical parameters related to postural stability. Clinical experiments were carefully designed and performed on 40 normal subjects. The results were that 1) postural stability decreased with age and 2) the best parameters were those of posture deviation measures. A customized PC-based software package was developed to apply the present technique with a great convenience to monitoring and analyzing postural stability in an accurate and quantitative way.

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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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