• Title/Summary/Keyword: Gross Errors

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Industrial application of gross error estimation and data reconciliation to byproduction gases in iron and steel making plants

  • Yi, Heui-Seok;Hakchul Shin;Kim, Jeong-Hwan;Chonghun Han
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.69.2-69
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    • 2002
  • Process measurements contain random and gross errors and the size estimation of gross errors is required for production accounting. Mixed integer programming technique had been applied to identify and estimate the gross errors simultaneously. However, the compensate model based on mixed integer programming used all measured variables or spanning tree as gross error candidates. This makes gross error estimation problem combinatorial or computationally expensive. Mixed integer programming with test statistics is proposed for computationally inexpensive gross error identification /estimation. The gross error candidates are identified by measurement test and the set of gross error candidates are...

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A Study on Automatic Detection of the Gross Errors on DSM Using Stereo Image Analysis (스테레오 영상분석에 기반한 DSM 과대오차영역의 자동검출기법연구)

  • Jeong, Jaehoon;Kim, Taejung
    • Korean Journal of Remote Sensing
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    • v.29 no.5
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    • pp.487-497
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    • 2013
  • In this paper, a method of using high resolution stereo images is proposed to efficiently detect DSM errors. Automatically generated DSMs from stereo matching can be a useful solution to acquire DSM data in various aspects but they may include many gross errors coming from automatic processing. Therefore, a method to detect the gross errors on DSM is required for efficient DSM update. In this paper, stereo analysis using high resolution stereo images was investigated to represent reliability of DSM grids. The analysis enabled automatic detection of the gross errors which greatly influenced DSM quality. We used the reference DSM to assess reliability of our proposed method. We confirmed from experimental results that our method can be a valuable DSM errors analysis for efficient DSM correction. Our method is useful to analyze and improve DSM accuracy for various types of DSM and DEM. It is expected that our approach can be exploited for achievement of reliable DSM and DEM.

Practical Understanding of Gross Examination Techniques (육안검사기술의 실무적 이해)

  • Woo-Hyun JI
    • Korean Journal of Clinical Laboratory Science
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    • v.56 no.1
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    • pp.89-98
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    • 2024
  • Gross examination techniques (GETs) of specimens collected from cancer surgery or endoscopy comprise the act of recording visual information about cancer for accurate histopathological diagnosis and collecting sections of the lesion to create microscopic specimens. GETs must include concise and accurate expressions, appropriate structuring, sufficient resections, error-free standardization of important information, and photo-diagramming of complex specimens. To increase the satisfaction of pathological interpretation, it is a task that must be performed accurately and carefully to gain confidence on a theoretical and practical basis with a sufficient understanding of gross examination. Based on the experience of clinical pathologists in the field of GETs, additional specimen types should be identified as viable candidates. Also, their needs and concerns regarding treatment should be carefully considered. In addition, departments at each institution should review the national focus on clinical partnerships, continuous professional training, diagnostic errors, and value-based healthcare provision.

Errors of MODIS product of Gross Primary Production by using Data Assimilation Office Meteorological Data (MODIS 총일차생산성 산출물의 오차요인 분석: 입력기상자료의 영향)

  • Kang Sinkyu;Kim Youngil;Kim Youngjin
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.7 no.2
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    • pp.171-183
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    • 2005
  • In order to monitor the global terrestrial carbon cycle, NASA (National Aeronautics and Space Administration) provides 8-day GPP images by use of satellite remote-sensing reflectance data from MODIS (Moderate Resolution Imaging Spectroradiometer) at l-km nadir spatial resolution since December, 1999. MODIS GPP algorithm adopts DAO (Data Assimilation Office) meteorological data to calculate daily GPP. By evaluating reliability of DAO data with respect to surface weather station data, we examined the effect of errors from DAO data on MODIS GPP estimation in the Korean Peninsula from 2001 to 2003. Our analyses showed that DAO data underestimated daily average temperature, daily minimum temperature, and daily vapor pressure deficity (VPD), but overestimated daily shortwave radiation during the study period. Each meteorological variable resulted in different spatial patterns of error distribution across the Korean Peninsula. In MODIS GPP estimation, DAO data resulted in overestimation of GPP by $25\%$ for all biome types but up to $40\%$ for forest biomes, the major biome type in the Korean Peninsula. MODIS GPP was more sensitive to errors in solar radiation and VPD than in temperatures. Our results indicate that more reliable gridded meteorological data than DAO data are necessary for satisfactory estimation of MODIS GPP in the Korean Peninsula.

DETERMINATION OF OPTIMAL ROBUST ESTIMATION IN SELF CALIBRATING BUNDLE ADJUSTMENT (자체검정 번들조정법에 있어서 최적 ROBUST추정법의 결정)

  • 유환희
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.9 no.1
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    • pp.75-82
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    • 1991
  • The objective of this paper is to investigate the optimal Robust estimation and scale estimator that could be used to treat the gross errors in a self calibrating bundle adjustment. In order to test the variability in performance of the different weighting schemes in accurately detecting gross error, five robust estimation methods and three types of scale estimators were used. And also, two difference control point patterns(high density control, sparse density control) and three types of gross errors(4$\sigma o$, 20$\sigma o$, 50$\sigma o$) were used for comparison analysis. As a result, Anscombe's robust estimation produced the best results in accuracy among the robust estimation methods considered. when considering the scale estimator about control point patterns, It can be seen that Type II scale estimator provided the best accuracy in high density control pattern. On the other hand, In the case of sparse density control pattern, Type III scale estimator showed the best results in accuracy. Therefore it is expected to apply to robustified bundle adjustment using the optimal scale estimator which can be used for eliminating the gross error in precise structure analysis.

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A Robust Backpropagation Algorithm and It's Application (문자인식을 위한 로버스트 역전파 알고리즘)

  • Oh, Kwang-Sik;Kim, Sang-Min;Lee, Dong-No
    • Journal of the Korean Data and Information Science Society
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    • v.8 no.2
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    • pp.163-171
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    • 1997
  • Function approximation from a set of input-output pairs has numerous applications in scientific and engineering areas. Multilayer feedforward neural networks have been proposed as a good approximator of nonlinear function. The back propagation(BP) algorithm allows multilayer feedforward neural networks to learn input-output mappings from training samples. It iteratively adjusts the network parameters(weights) to minimize the sum of squared approximation errors using a gradient descent technique. However, the mapping acquired through the BP algorithm may be corrupt when errorneous training data we employed. When errorneous traning data are employed, the learned mapping can oscillate badly between data points. In this paper we propose a robust BP learning algorithm that is resistant to the errorneous data and is capable of rejecting gross errors during the approximation process, that is stable under small noise perturbation and robust against gross errors.

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Analysis of the Internal Reliability in Relative Orientation and Independent Model Method (상호표정 및 독립모델법에서의 내적신뢰성 분석)

  • 양인태
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.5 no.1
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    • pp.59-65
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    • 1987
  • This paper presented the procedures for detecting gross errors, and described the influence of the number and distribution of points on the internal reliability in photogrammetric adjustment, such as relative orientation and independent model method. The use of the standard six points for relative orientation and the regular four points for independent model method result in low internal reliability. With such a distribution, gross erors in measured points might not be detected But using cluster of double or triple points instead of individual point, internal reliability improves remarkably.

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Comparative Analysis of Performance of Established Pitch Estimation Methods in Sustained Vowel of Benign Vocal Fold Lesions (양성후두 질환의 지속모음을 대상으로 한 기존 피치 추정 방법들의 성능 비교 분석)

  • Jang, Seung-Jin;Kim, Hyo-Min;Choi, Seong-Hee;Park, Young-Cheol;Choi, Hong-Shik;Yoon, Young-Ro
    • Speech Sciences
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    • v.14 no.4
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    • pp.179-200
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    • 2007
  • In voice pathology, various measurements calculated from pitch values are proposed to show voice quality. However, those measurements frequently seem to be inaccurate and unreliable because they are based on some wrong pitch values determined from pathological voice data. In order to solve the problem, we compared several pitch estimation methods to propose a better one in pathological voices. From the database of 99 pathological voice and 30 normal voice data, errors derived from pitch estimation were analyzed and compared between pathological and normal voice data or among the vowels produced by patients with benign vocal fold lesions. Results showed that gross pitch errors were observed in the cases of pathological voice data. From the types of pathological voices classified by the degree of aperiodicity in the speech signals, we found that pitch errors were closely related to the number of aperiodic segments. Also, the autocorrelation approach was found to be the most robust pitch estimation in the pathological voice data. It is desirable to conduct further research on the more severely pathological voice data in order to reduce pitch estimation errors.

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ON THE MINIMAX VARIANCE ESTIMATORS OF SCALE IN TIME TO FAILURE MODELS

  • Lee, Jae-Won;Shevlyakov, Georgy-L.
    • Bulletin of the Korean Mathematical Society
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    • v.39 no.1
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    • pp.23-31
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    • 2002
  • A scale parameter is the principal parameter to be estimated, since it corresponds to one of the main reliability characteristics, namely the average time to failure. To provide robustness of scale estimators to gross errors in the data, we apply the Huber minimax approach in time to failure models of the statistical reliability theory. The minimax valiance estimator of scale is obtained in the important particular case of the exponential distribution.