• Title/Summary/Keyword: Exponential Moving Average

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An Extension of the Optimality of Exponential Smoothing to Integrated Moving Average Process (일반적인 IMA과정에 대한 지수평활 최적성의 확장)

  • Park, Hae-Chul;Park, Sung-Joo
    • Journal of the military operations research society of Korea
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    • v.8 no.1
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    • pp.99-107
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    • 1982
  • This paper is concerned with the optimality of exponential smoothing applied to the general IMA process with different moving average and differencing orders. Numerical experiments were performed for IMA(m,n) process with various combinations of m and n, and the corresponding forecast errors were compared. Results show that the higher differencing order is more critical to the optimality of exponential smoothing, i.e., the IMA process with the higher moving average order, forecasted by exponential smoothing, has comparatively smaller forecast error. If the difference between the differencing order and the moving average order becomes larger, the accuracy of forecast by exponential smoothing declines gradually.

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ESD(Exponential Standard Deviation) Band centered at Exponential Moving Average (지수이동평균을 중심으로 하는 ESD밴드)

  • Lee, Jungyoun;Hwang, Sunmyung
    • Journal of Intelligence and Information Systems
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    • v.22 no.2
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    • pp.115-125
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    • 2016
  • The Bollinger Band indicating the current price position in the recent price action range is obtained by adding/substracting the simple standard deviation (SSD) to/from the simple moving average (SMA). In this paper, we first compare the characteristics of the SMA and the exponential moving average (EMA) in the operator's point of view. A basic equation is obtained between the interval length N of the SMA operator and the weighting factor ${\rho}$ of the EMA operator, that makes the centers of the 1st order momentums of each operator impulse respoinse identical. For equivalent N and ${\rho}$, frequency response examples are obtained and compared by using the discrete time Fourier transform. Based on observation that the SMA operator reacts more excessively than the EMA operator, we propose a novel exponential standard deviation (ESD) band centered at the EMA and derive an auto recursive formula for the proposed ESD band. Practical examples for the ESD band show that it has a smoother bound on the price action range than the Bollinger Band. Comparisons are also made for the gap corrected chart to show the advantageous feature of the ESD band even in the case of gap occurrence. Trading techniques developed for the Bollinger Band can be straight forwardly applied to those for the ESD band.

Efficient Anomaly Detection Through Confidence Interval Estimation Based on Time Series Analysis

  • Kim, Yeong-Ju;Jeong, Min-A
    • International journal of advanced smart convergence
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    • v.4 no.2
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    • pp.46-53
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    • 2015
  • This paper suggests a method of real time confidence interval estimation to detect abnormal states of sensor data. For real time confidence interval estimation, the mean square errors of the exponential smoothing method and moving average method, two of the time series analysis method, were compared, and the moving average method with less errors was applied. When the sensor data passes the bounds of the confidence interval estimation, the administrator is notified through alarms. As the suggested method is for real time anomaly detection in a ship, an Android terminal was adopted for better communication between the wireless sensor network and users. For safe navigation, an administrator can make decisions promptly and accurately upon emergency situation in a ship by referring to the anomaly detection information through real time confidence interval estimation.

Forecasting of Passenger Numbers, Freight Volumes and Optimal Tonnage of Passenger Ship in Mokpo Port (목포항 여객수 및 적정 선복량 추정에 관한 연구)

  • Jang, Woon-Jae;Keum, Jong-Soo
    • Journal of Navigation and Port Research
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    • v.28 no.6
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    • pp.509-515
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    • 2004
  • The aim of this paper is to forecast passenger numbers and freight volumes in 2005 and it is proposed optimal tonnage of passenger ship. The forecasting of passenger numbers and freight volumes is important problem in order to determine optimal tonnage of passenger ship, port plan and development. In this paper, the forecasting of passenger numbers and freight volumes are performed by the method of neural network using back-propagation learning algorithm. And this paper compares the forecasting performance of neural networks with moving average method and exponential smooth method As the result of analysis. The forecasting of passenger numbers and freight volumes is that the neural networks performed better than moving average method and exponential smoothing method on the basis of MSE(mean square error) and MAE(mean absolute error).

A WEAKLY DEPENDENCE CONCEPT IN MOVING AVERAGE MODELS

  • Baek, Jong-Il;Lim, Ho-Un;Youn, Eun-Ho
    • Communications of the Korean Mathematical Society
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    • v.12 no.3
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    • pp.743-754
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    • 1997
  • We introduce a class of finite and infinite moving average (MA) sequences of multivariate random vectors exponential marginals. The theory of dependence is used to show that in various cases the class of MA sequences consists of associated random variables. We utilize positive dependence properties to obtain some probability bounds for the multivariate processes.

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The Motion Artifact Reduction from the PPG based on EWMA (지수가중 이동평균 기반의 PPG 신호 동잡음 제거)

  • Lee, Jun-Yeon
    • Journal of Digital Convergence
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    • v.11 no.8
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    • pp.183-190
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    • 2013
  • The Photoplethysmogram is a similar periodic signal that synchrinized to a heartbeat. In this paper, we propose a exponential weight moving average filter that use similarity of Photoplethysmogram. This filtering method has the average value of each samples through separating the cycle of PPG signal. If there are some motion artifacts in continuous PPG signal, disjoin the signal based on cycle. And then, we made these signals to have same cycle by coordinating the number of sample. After arrange these cycles in 2 dimension, we put the average value of each samples from starting till now. So, we can eliminate the motion artifacts without damaged PPG signal.

Daily Maximum Electric Load Forecasting for the Next 4 Weeks for Power System Maintenance and Operation (전력계통 유지보수 및 운영을 위한 향후 4주의 일 최대 전력수요예측)

  • Jung, Hyun-Woo;Song, Kyung-Bin
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.63 no.11
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    • pp.1497-1502
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    • 2014
  • Electric load forecasting is essential for stable electric power supply, efficient operation and management of power systems, and safe operation of power generation systems. The results are utilized in generator preventive maintenance planning and the systemization of power reserve management. Development and improvement of electric load forecasting model is necessary for power system maintenance and operation. This paper proposes daily maximum electric load forecasting methods for the next 4 weeks with a seasonal autoregressive integrated moving average model and an exponential smoothing model. According to the results of forecasting of daily maximum electric load forecasting for the next 4 weeks of March, April, November 2010~2012 using the constructed forecasting models, the seasonal autoregressive integrated moving average model showed an average error rate of 6,66%, 5.26%, 3.61% respectively and the exponential smoothing model showed an average error rate of 3.82%, 4.07%, 3.59% respectively.

Advanced Process Control of the Critical Dimension in Photolithography

  • Wu, Chien-Feng;Hung, Chih-Ming;Chen, Juhn-Horng;Lee, An-Chen
    • International Journal of Precision Engineering and Manufacturing
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    • v.9 no.1
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    • pp.12-18
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    • 2008
  • This paper describes two run-to-run controllers, a nonlinear multiple exponential-weight moving-average (NMEWMA) controller and a dynamic model-tuning minimum-variance (DMTMV) controller, for photolithography processes. The relationships between the input recipes (exposure dose and focus) and output variables (critical dimensions) were formed using an experimental design method, and the photolithography process model was built using a multiple regression analysis. Both the NMEWMA and DMTMV controllers could update the process model and obtain the optimal recipes for the next run. Quantified improvements were obtained from simulations and real photolithography processes.

Suggesting Forecasting Methods for Dietitians at University Foodservice Operations

  • Ryu Ki-Sang
    • Nutritional Sciences
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    • v.9 no.3
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    • pp.201-211
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    • 2006
  • The purpose of this study was to provide dietitians with the guidance in forecasting meal counts for a university/college foodservice facility. The forecasting methods to be analyzed were the following: naive model 1, 2, and 3; moving average, double moving average, simple exponential smoothing, double exponential smoothing, Holt's, and Winters' methods, and simple linear regression. The accuracy of the forecasting methods was measured using mean squared error and Theil's U-statistic. This study showed how to project meal counts using 10 forecasting methods for dietitians. The results of this study showed that WES was the most accurate forecasting method, followed by $na\ddot{i}ve$ 2 and naive 3 models. However, naive model 2 and 3 were recommended for using by dietitians in university/college dining facilities because of the accuracy and ease of use. In addition, the 2000 spring semester data were better than the 2000 fall semester data to forecast 2001spring semester data.

The Analysis of Traffic Flow Characteristics on Moving Bottleneck (연속류 시설의 이동병목구간에서 지체산정방법 -모의실험을 통한 교통류의 평균지체분석-)

  • Kim, Won-Kyu;Jeong, Myeong-Kyu;Kim, Byung-Jong;Seo, Eun-Chae;Kim, Song-Ju
    • Journal of The Institute of Information and Telecommunication Facilities Engineering
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    • v.8 no.4
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    • pp.170-181
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    • 2009
  • When a slow-moving vehicle occupies one of the lanes of a multi-lane highway, it often causes queuing behind, unlike one is caused by an actual stoppage on that lane. This happens when the traffic flow rate upstream from the slow vehicle exceeds a certain critical value. This phenomena is called as the Moving Bottleneck, defined by Gazis and Herman (1992), Newell (1998) [3], and Munoz and Daganzo (2002), who conducted the flow estimates of upstream and downstream and considered slow-moving vehicle speed and the flow ratio exceeding slow vehicle and the microscopic traffic flow characteristics of moving bottleneck. But, a study of delay on moving bottleneck was not conducted until now. So this study provides a average delay time model related to upstream flow and the speed of slow vehicle. We have chosen the two-lane highway and homogeneous traffic flow. A slow-moving vehicle occupies one of the two lanes. Average delay time value is a result of AIMSUN[9], the microscopic traffic flow simulator. We developed a multiple regression model based on that value. Average delay time has a high value when the speed of slow vehicle is decreased and traffic flow is increased. Conclusively, the model is formulated by the negative exponential function.

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