• Title/Summary/Keyword: Absolute mean

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A Gaussian Jet Model for Deriving Absolute Geostrophic Velocity from Satellite Altimetry

  • Kim, Seung-Bum
    • Proceedings of the KSRS Conference
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    • 2002.10a
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    • pp.610-614
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    • 2002
  • Time-mean and absolute geostrophic velocities of the Kuroshio current south of Japan are derived from TOPEX/Poseidon altimeter data using a Gaussian jet model. When compared with simultaneous measurements from a shipboard acoustic Doppler current profiler (ADCP) at two intersection points, the altimetric and ADCP absolute velocities correlate well with the correlation of 0.55 to 0.74. The time-mean velocity is accurate to 1 cm s$^{-1}$ to 5 cm s$^{-1}$. The errors in the absolute and the mean velocities are similar to those reported previously far other currents. The comparable performance suggests the Gaussian jet model is a promising methodology for determining absolute geostrophic velocities, noting that in this region the Kuroshio does not meander sufficiently, which provides unfavorable environment for the performance of the Gaussian jet model.

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Detection of the Normal Population with the Largest Absolute Value of Mean

  • Kim, Woo-Chul;Jeong, Gyu-Jin
    • Journal of the Korean Statistical Society
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    • v.22 no.1
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    • pp.71-81
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    • 1993
  • Among k independent normal populations with unknown means and a common unknown variance, the problem of detecting the population with the largest absolute value of mean is considered. This problem is formulated in a manner close to the framework of testing hypotheses, and the maximum error probability and the minimum power are considered. The power charts necessary to determine the sample size are provided. The problem of detecting the population with the smallest absolute value of mean is also considered.

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Minimizing the Weighted Mean Absolute Deviation of Completion Times about a Common Due Date (공통납기에 대한 완료시간의 W.M.A.D. 최소화에 관한 연구)

  • 오명진;최종덕
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.13 no.21
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    • pp.143-151
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    • 1990
  • This paper studies a single machine scheduling problem in which all jobs have the common due date and penalties are assessed for jobs at different rates. The scheduling objective is to minimize the weighted mean absolute deviations(WMAD). This problem may provide greater flexibility in achieving scheduling objectives than the mean absolute deviation (MAD) problem. We propose three heuristic solution methods based on several dominance conditions. Numerical examples are presented. This article extends the results to the problem to the problem of scheduling n-jobs on m-parallel identical processors in order to minimize the weighted mean absolute deviation.

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Contrast Image Enhancement Using Multi-Histogram Equalization

  • Phanthuna, Nattapong;cheevasuwit, Fusak
    • International Journal of Advanced Culture Technology
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    • v.3 no.2
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    • pp.161-170
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    • 2015
  • Mean separated histogram equalization in order to preserve the original mean brightness has been proposed. To provide the minimum mean brightness error after the histogram modification, the input image's histogram is successively divided by the factor of 2 until the mean brightness error is satisfied the defined threshold. Then each divided group or sub-histogram will be independently equalized based on the proportional input mean. To provide the overall minimum mean brightness error, each group will be controlled by adding some certain pixels from the adjacent grey level of the next group for giving its mean near by the corresponding the divided mean. However, it still exists some little error which will be put into the next adjacent group. By successive dividing the original histogram, we found that the absolute mean brightness error is gradually decreased when the number of group is increased. Therefore, the error threshold is assigned in order to automatically dividing the original histogram for obtaining the desired absolute mean brightness error (AMBE). This process will be applied to the color image by treating each color independently.

Estimation Method of Predicted Time Series Data Based on Absolute Maximum Value (최대 절대값 기반 시계열 데이터 예측 모델 평가 기법)

  • Shin, Ki-Hoon;Kim, Chul;Nam, Sang-Hun;Park, Sung-Jae;Yoo, Sung-Soo
    • Journal of Energy Engineering
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    • v.27 no.4
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    • pp.103-110
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    • 2018
  • In this paper, we introduce evaluation method of time series prediction model with new approach of Mean Absolute Percentage Error(hereafter MAPE) and Symmetric Mean Absolute Percentage Error(hereafter sMAPE). There are some problems using MAPE and sMAPE. First MAPE can't evaluate Zero observation of dataset. Moreover, when the observed value is very close to zero it evaluate heavier than other methods. Finally it evaluate different measure even same error between observations and predicted values. And sMAPE does different evaluations are made depending on whether the same error value is over-predicted or under-predicted. And it has different measurement according to the each sign, even if error is the same distance. These problems were solved by Maximum Mean Absolute Percentage Error(hereafter mMAPE). we used the absolute maximum of observed value as denominator instead of the observed value in MAPE, when the value is less than 1, removed denominator then solved the problem that the zero value is not defined. and were able to prevent heavier measurement problem. Also, if the absolute maximum of observed value is greater than 1, the evaluation values of mMAPE were compared with those of the other evaluations. With Beijing PM2.5 temperature data and our simulation data, we compared the evaluation values of mMAPE with other evaluations. And we proved that mMAPE can solve the problems that we mentioned.

Geostrophic Velocities Derived from Satellite Altimetry in the Sea South of Japan

  • Kim, Seung-Bum
    • Korean Journal of Remote Sensing
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    • v.18 no.5
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    • pp.243-253
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    • 2002
  • Time-mean and absolute geostrophic velocities of the Kuroshio current south of Japan are derived from TOPEX/Poseidon altimeter data using a Gaussian jet model. When compared with simultaneous measurements from a shipboard acoustic Doppler current profiler (ADCP) at two intersection points, the altimetric and ADCP absolute velocities correlate well with the correlation coefficient of 0.55 to 0.74. The accuracy of time-mean velocity ranges from 1 cm s$^{-1}$ to 5 cm s$^{-1}$. The errors in the absolute and the mean velocities are similar to those reported previously for other currents. The comparable performance suggests the Gaussian jet model is a promising methodology for determining absolute geostrophic velocities, noting that in this region the Kuroshio does not meander sufficiently and thus provides unfavorable environment for the performance of the Gaussian jet model.

Short-term Power Consumption Forecasting Based on IoT Power Meter with LSTM and GRU Deep Learning (LSTM과 GRU 딥러닝 IoT 파워미터 기반의 단기 전력사용량 예측)

  • Lee, Seon-Min;Sun, Young-Ghyu;Lee, Jiyoung;Lee, Donggu;Cho, Eun-Il;Park, Dae-Hyun;Kim, Yong-Bum;Sim, Isaac;Kim, Jin-Young
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.19 no.5
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    • pp.79-85
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    • 2019
  • In this paper, we propose a short-term power forecasting method by applying Long Short Term Memory (LSTM) and Gated Recurrent Unit (GRU) neural network to Internet of Things (IoT) power meter. We analyze performance based on real power consumption data of households. Mean absolute error (MAE), mean absolute percentage error (MAPE), mean percentage error (MPE), mean squared error (MSE), and root mean squared error (RMSE) are used as performance evaluation indexes. The experimental results show that the GRU-based model improves the performance by 4.52% in the MAPE and 5.59% in the MPE compared to the LSTM-based model.

Convergence Analysis of the Modified Adaptive Sign (MAS) Algorithm Using a Mixed Norm Error Criterion

  • Lee, Young-Hwan
    • The Journal of the Acoustical Society of Korea
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    • v.16 no.3E
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    • pp.62-68
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    • 1997
  • In this paper, a modified adaptive sign (MAS) algorithm based on a mixed norm error criterion is proposed. The mixed norm error criterion of be minimized is constructed as a combined convex function of the mean-absolute error and the mean-absolute error to the third power. A convergence analysis of the MAS algorithm is also presented. Under a set of mild assumptions, a set of nonlinear evolution equations that characterizes the statistical mean and mean-squared behavior of the algorithm is derived. Computed simulations are carried out to verify the validity of our derivations.

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An Advanced Successive Elimination Algorithm Using Mean Absolute Difference of Neighboring Search Points (경계점의 절대 오차 평균을 이용한 개선된 연속 제거 알고리즘)

  • Jung, Soo-Mok
    • Journal of the Korea Computer Industry Society
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    • v.5 no.5
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    • pp.755-760
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    • 2004
  • In this paper, an advanced successive elimination algorithm was proposed using mean absolute difference of neighboring search points. By using mean absolute difference of neighboring search points, the search point in motion estimation can be eliminated effeciently without matching evaluation that requires very intensive computations. By using adaptive MAD calculation algorithm, the candidate matching block can be eliminated early. So, the number of the proposed algrorithm was verified by experimental results.

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Prediction of Chest Deflection Using Frontal Impact Test Results and Deep Learning Model (정면충돌 시험결과와 딥러닝 모델을 이용한 흉부변형량의 예측)

  • Kwon-Hee Lee;Jaemoon Lim
    • Journal of Auto-vehicle Safety Association
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    • v.15 no.1
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    • pp.55-62
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    • 2023
  • In this study, a chest deflection is predicted by introducing a deep learning technique with the results of the frontal impact of the USNCAP conducted for 110 car models from MY2018 to MY2020. The 120 data are divided into training data and test data, and the training data is divided into training data and validation data to determine the hyperparameters. In this process, the deceleration data of each vehicle is averaged in units of 10 ms from crash pulses measured up to 100 ms. The performance of the deep learning model is measured by the indices of the mean squared error and the mean absolute error on the test data. A DNN (Deep Neural Network) model can give different predictions for the same hyperparameter values at every run. Considering this, the mean and standard deviation of the MSE (Mean Squared Error) and the MAE (Mean Absolute Error) are calculated. In addition, the deep learning model performance according to the inclusion of CVW (Curb Vehicle Weight) is also reviewed.