• Title/Summary/Keyword: Standard error

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Time Series Prediction Using a Multi-layer Neural Network with Low Pass Filter Characteristics (저주파 필터 특성을 갖는 다층 구조 신경망을 이용한 시계열 데이터 예측)

  • Min-Ho Lee
    • Journal of Advanced Marine Engineering and Technology
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    • v.21 no.1
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    • pp.66-70
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    • 1997
  • In this paper a new learning algorithm for curvature smoothing and improved generalization for multi-layer neural networks is proposed. To enhance the generalization ability a constraint term of hidden neuron activations is added to the conventional output error, which gives the curvature smoothing characteristics to multi-layer neural networks. When the total cost consisted of the output error and hidden error is minimized by gradient-descent methods, the additional descent term gives not only the Hebbian learning but also the synaptic weight decay. Therefore it incorporates error back-propagation, Hebbian, and weight decay, and additional computational requirements to the standard error back-propagation is negligible. From the computer simulation of the time series prediction with Santafe competition data it is shown that the proposed learning algorithm gives much better generalization performance.

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Statistical analysis of KNHANES data with measurement error models

  • Hwang, Jinseub
    • Journal of the Korean Data and Information Science Society
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    • v.26 no.3
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    • pp.773-779
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    • 2015
  • We study a statistical analysis about the fifth wave data of the Korea National Health and Nutrition Examination Survey based on linear regression models with measurement errors. The data is obtained from a national population-based complex survey. To demonstrate the availability of measurement error models, two results between the general linear regression model and measurement error model are compared based on the model selection criteria which are Akaike information criterion and Bayesian information criterion. For our study, we use the simulation extrapolation algorithm for measurement error model and the jackknife method for the estimation of standard errors.

ROBUST A POSTERIORI ERROR ESTIMATOR FOR LOWEST-ORDER FINITE ELEMENT METHODS OF INTERFACE PROBLEMS

  • KIM, KWANG-YEON
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.20 no.2
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    • pp.137-150
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    • 2016
  • In this paper we analyze an a posteriori error estimator based on flux recovery for lowest-order finite element discretizations of elliptic interface problems. The flux recovery considered here is based on averaging the discrete normal fluxes and/or tangential derivatives at midpoints of edges with weight factors adapted to discontinuous coefficients. It is shown that the error estimator based on this flux recovery is equivalent to the error estimator of Bernardi and $Verf{\ddot{u}}rth$ based on the standard edge residuals uniformly with respect to jumps of the coefficient between subdomains. Moreover, as a byproduct, we obtain slightly modified weight factors in the edge residual estimator which are expected to produce more accurate results.

Development of a Task Analysis Method and Classification of Emergency Tasks for Human Error Analysis in Nuclear Power Plants (원자력발전소 오류분석을 위한 직무분석 방법의 개발 및 직무유형 분류)

  • 정원대;박진균;김재환
    • Journal of the Korean Society of Safety
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    • v.16 no.4
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    • pp.168-174
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    • 2001
  • For human error analysis, the structure and situation of a task should be analyzed in advance. The paper introduces Structured Information Analysis (SIA) as a task analysis method for error analysis, and delineates the result of application on the emergency procedure of Korean Standard Nuclear Plants (KSNPs). From the task analysis about emergency procedure of KSNP, total 72 specific task goals were identified in the level of system function, and 86 generic tasks were classified from the viewpoint of physical sameness of the task description. Human errors are dependent on task types so that the result of task analysis would be used as a basis for the error analysis on the emergency tasks in nuclear power plants.

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Monte-Carlo Simulation and measuring for Error Analysis of 3-axis SCARA Robot using Observability (관측성을 이용한 3축 SCARA Robot의 오차분석을 위한 Monte-Carlo simulation 및 측정)

  • Ju, Ji-Hun;Chung, Won-Jee;Kim, Jung-Hyun
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.17 no.4
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    • pp.8-14
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    • 2008
  • This paper aims at finding out dominant robot configurations with maximal position errors, which can be attributed to the parameter errors, by using Monte-Carlo simulation for error analysis of a 3-axis SCARA(Selective Compliance Assembly Robot Arm) type robot. In particular, the Monte-Carlo simulation is used for virtually measuring on the position errors, instead of physical measurement. In order to measure the observability of the model parameters with respect to a set of robot configurations, we propose the observability index which is defined as the product of singular values for error propagation matrices. Thus the index can be used for discriminating dominant robot configurations from a set of simulated ones in conjunction with standard deviation of positional errors, This paper analyzed error by robot positional error.

Comparative Transmission of JPEG2000 and MPEG-4 Patient Images using the Error Resilient Tools over CDMA 1xEVDO Network (CDMA 1xEVDO 망에서 무선 에러에 강인한 JPEG2000과 MPEG4의 환자 영상 전송에 관한 비교연구)

  • Cho, Jin-Ho;Lee, Tong-Heon;Yoo, Sun-Kook
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.55 no.6
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    • pp.296-301
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    • 2006
  • Even though the emergency telecommunication make possible that specialist offers medical care over emergency cases in moving vehicle, we still have many problems in transmitting the image or video of patient over several wireless networks. To alleviate the effect of channel errors on compressed video bit-stream, this paper analyzed the error resilient features of JPEG2000 standard and measured the quality of transmission over noisy wireless channel, CDMA2000 1xEV-DO networks, compared to the features of error resilient tool of MPEG-4. We also proposed the optimum solution of transmitting images over real 3G network using JPEG2000 error resilient tool.

Performance Anomaly of the IEEE 802.11 DCF in Different Frame Error Rate Conditions

  • Kang, Koohong
    • Journal of Information Processing Systems
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    • v.8 no.4
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    • pp.739-748
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    • 2012
  • We propose an analytic model to compute the station's saturated throughput and packet delay performance of the IEEE 802.11 DCF (Distributed Coordination Function) in which frame transmission error rates in the channel are different from each other. Our analytic model shows that a station experiencing worse frame error rates than the others suffers severe performance degradation below its deserved throughput and delay performance. 802.11 DCF adopts an exponential back-off scheme. When some stations suffer from high frame error rates, their back-off stages should be increased so that others get the benefit from the smaller collision probabilities. This impact is then recursively applied to degrade the performance of the victim stations. In particular, we show that the performance is considerably degraded even if the frame error rate of the victim station satisfies the receiver input level sensitivity that has been specified in the IEEE 802.11 standard. We also verify the analytic results by the OPNET simulations.

A Study on the proficiency test of pH measurements (pH 측정의 숙련도 시험에 대한 연구)

  • Lee, Hwashim;Kim, Myungsoo;Choi, Jongoh
    • Analytical Science and Technology
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    • v.14 no.3
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    • pp.230-237
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    • 2001
  • In general, the pH measurement follows calibration of glass electrode system using pH standard solution. When pH is measured at constant temperature, uncertainty factors are mainly related to the accuracy of pH standard solution and the accuracy and precision of glass electrode. Participants in this proficiency test were the volunteers trying to know the distribution of the measured pH values for the same sample and the sources of error through 1998 and 1999. The samples for proficiency test are phosphate salt standard solutions specially prepared in KRISS, of which pH values were 6.860, 7.415(at $25^{\circ}C$), and the stability test was performed for the same periods of proficiency test. The results of the proficiency test were plotted according to Youden plot, which shows whether the error is random or systematic. The results of Youden plot showed that the source of error was from the systematic effect of laboratories in each year. This shows that the source of error is the standard solutions used in laboratories.

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The Influence Analysis of Support Working Expenses for Yongdam Dam Area Considering the Resolution of Digital Topographic Map (수치지형도 해상도를 고려한 용담댐 주변지역 지원사업비 영향 분석)

  • Lee, Geun Sang
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.30 no.5D
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    • pp.523-531
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    • 2010
  • A dam is effective in stable supply of water required in daily life and reduced damage from floods, but there are problems as a lot of land or houses are submerged. Therefore many projects have been conducted in order to improve and support daily life environment surrounding a dam. This study has focused on analyzing how to calculate support working expenses for Dam area by using GIS spatial overlay in addition to effects of scale of a topographic map and reached the following conclusion. First, as a result of areal error in submerged area by scale based on a 1/3,000 digital topographic map, it has been found that a 1/5,000 digital topographic map is 9.5 times more accurate than a 1/25,000 digital topographic map in the total of areal error. Second, as a result of areal error in area surrounding a dam, it has been found that a 1/5,000 digital topographic map is 7.4 times more accurate than a 1/25,000 digital topographic map in the total of areal error. Third, as a result of error of support expense for submerged area, it has been found that a 1/5,000 digital topographic is 15.9 times, 14.7 times and 15.9 times more effective than a 1/25,000 digital topographic map in terms of the total error of support expense, standard error and the total support expense error on the entire project costs in submerged area. In addition, as a result of analysis on error of support expense for area surrounding a dam, it has been found that a 1/5,000 digital topographic map was 10.7 times, 9.6 times and 10.6 times more effective, respectively, in the total error of support expense, standard error and the total error of support expense for the entire project costs in area surrounding a dam compared to a 1/25,000 digital topographic map. Lastly, as a result of error of the entire project costs for area surrounding a dam, it has been found that a 1/5,000 digital topographic map was 1.4 times, 1.3 times and 1.4 times more effective, respectively, in the total error of support expense, standard error and the total error of the entire project costs compared to a 1/25,000 digital topographic map, but it was not much different from the result of calculating areal error in submerged area or area surrounding a dam because population item didn't consider areal concept.

A Study of Using the Terminology of Sampling Error and Sampling Distribution (표집오차(sampling error)와 표집분포(sampling distribution)의 용어 사용에 관한 연구)

  • Kim, Yung-Hwan
    • Journal of the Korean School Mathematics Society
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    • v.9 no.3
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    • pp.309-316
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    • 2006
  • This study examined the ambiguous using the terminology of statistics at mathematics textbook of highschool in Korea and proposed the correct using of sampling error and sampling distribution of sample mean with consistency. And this paper proposed that the concept of error have to teach in context of sampling action in school mathematics.

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