• Title/Summary/Keyword: prediction method

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Call Admission Control Using Adaptive-MMOSPRED for Resource Prediction in Wireless Networks (무선망의 자원예측을 위한 Adaptive-MMOSPRED 기법을 사용한 호 수락제어)

  • Lee, Jin-Yi
    • Journal of Advanced Navigation Technology
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    • v.12 no.1
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    • pp.22-27
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    • 2008
  • This paper presents adaptive-MMOSPRED method for prediction of resource demands requested by multimedia calls, and shows the performance of the call admission control based on proposed resource prediction method in multimedia wireless networks. The proposed method determines (I-CDP) random variables of the standard normal distribution by using LMS algorithm that minimize errors of prediction in resource demands, while parameters in an existing method are constant all through the prediction time. Our simulation results show that prediction error in adaptive-MMOSPRED method is much smaller than in fixed-MMOSPRED method. Also we can see via simulation the CAC performance based on the proposed method improves the new call blocking performance compared with the existing method under the desired handoff dropping probability.

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A Climate Prediction Method Based on EMD and Ensemble Prediction Technique

  • Bi, Shuoben;Bi, Shengjie;Chen, Xuan;Ji, Han;Lu, Ying
    • Asia-Pacific Journal of Atmospheric Sciences
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    • v.54 no.4
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    • pp.611-622
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    • 2018
  • Observed climate data are processed under the assumption that their time series are stationary, as in multi-step temperature and precipitation prediction, which usually leads to low prediction accuracy. If a climate system model is based on a single prediction model, the prediction results contain significant uncertainty. In order to overcome this drawback, this study uses a method that integrates ensemble prediction and a stepwise regression model based on a mean-valued generation function. In addition, it utilizes empirical mode decomposition (EMD), which is a new method of handling time series. First, a non-stationary time series is decomposed into a series of intrinsic mode functions (IMFs), which are stationary and multi-scale. Then, a different prediction model is constructed for each component of the IMF using numerical ensemble prediction combined with stepwise regression analysis. Finally, the results are fit to a linear regression model, and a short-term climate prediction system is established using the Visual Studio development platform. The model is validated using temperature data from February 1957 to 2005 from 88 weather stations in Guangxi, China. The results show that compared to single-model prediction methods, the EMD and ensemble prediction model is more effective for forecasting climate change and abrupt climate shifts when using historical data for multi-step prediction.

Displacement prediction in geotechnical engineering based on evolutionary neural network

  • Gao, Wei;He, T.Y.
    • Geomechanics and Engineering
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    • v.13 no.5
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    • pp.845-860
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    • 2017
  • It is very important to study displacement prediction in geotechnical engineering. Nowadays, the grey system method, time series analysis method and artificial neural network method are three main methods. Based on the brief introduction, the three methods are analyzed comprehensively. Their merits and demerits, applied ranges are revealed. To solve the shortcomings of the artificial neural network method, a new prediction method based on new evolutionary neural network is proposed. Finally, through two real engineering applications, the analysis of three main methods and the new evolutionary neural network method all have been verified. The results show that, the grey system method is a kind of exponential approximation to displacement sequence, and time series analysis is linear autoregression approximation, while artificial neural network is nonlinear autoregression approximation. Thus, the grey system method can suitably analyze the sequence, which has the exponential law, the time series method can suitably analyze the random sequence and the neural network method almostly can be applied in any sequences. Moreover, the prediction results of new evolutionary neural network method is the best, and its approximation sequence and the generalization prediction sequence are all coincided with the real displacement sequence well. Thus, the new evolutionary neural network method is an acceptable method to predict the measurement displacements of geotechnical engineering.

A Comparative Study on the Prediction of the Final Settlement Using Preexistence Method and ARIMA Method (기존기법과 ARIMA기법을 활용한 최종 침하량 예측에 관한 비교 연구)

  • Kang, Seyeon
    • Journal of the Korean GEO-environmental Society
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    • v.20 no.10
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    • pp.29-38
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    • 2019
  • In stability and settlement management of soft ground, the settlement prediction technology has been continuously developed and used to reduce construction cost and confirm the exact land use time. However, the preexistence prediction methods such as hyperbolic method, Asaoka method and Hoshino method are difficult to predict the settlement accurately at the beginning of consolidation because the accurate settlement prediction is possible only after many measurement periods have passed. It is judged as the reason for estimating the future settlement through the proportionality assumption of the slope which the preexistence prediction method computes from the settlement curve. In this study, ARIMA technique is introduced among time series analysis techniques and compared with preexistence prediction methods. ARIMA method was predictable without any distinction of ground conditions, and the results similar to the existing method are predicted early (final settlement).

A Prediction Cost based Complexity Reduction Method for Bi-Prediction in High Efficiency Video Coding (HEVC) (HEVC의 양-예측을 위한 예측 비용 기반의 복잡도 감소 기법)

  • Kim, Jong-Ho;Lee, Ha-Hyun;Jun, Dong-San;Cho, Suk-Hee;Choi, Jin-Soo
    • Journal of Broadcast Engineering
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    • v.17 no.5
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    • pp.781-788
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    • 2012
  • In HEVC, the fast search method is used for reducing the complexity of the motion prediction procedure. It is consisted of the sub-sampled SAD which reduce the complexity of Sum of Absolute Differences(SAD) calculation and the simplified bi-prediction method which reduce the iterations of the uni-prediction for the bi-prediction. The computational complexity is largely decreased by the fast search method but the coding gain is also decreased. In this paper, the simplified bi-prediction is extended to compensate the performance loss and the prediction cost based complexity reduction methods are also proposed to reduce the complexity burden by the extended bi-prediction method. A prediction cost based complexity reduction method is consisted of early termination method for the extended bi-prediction and the bi-prediction skipping method. Compare with HM 6.0 references S/W, the average 0.42% of BD-bitrate is decreased by both the extended bi-prediction method and the prediction cost based complexity reduction methods with negligible increasement of the complexity.

Design of HCBKA-Based TSK Fuzzy Prediction System with Error Compensation (HCBKA 기반 오차 보정형 TSK 퍼지 예측시스템 설계)

  • Bang, Young-Keun;Lee, Chul-Heui
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.59 no.6
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    • pp.1159-1166
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    • 2010
  • To improve prediction quality of a nonlinear prediction system, the system's capability for uncertainty of nonlinear data should be satisfactory. This paper presents a TSK fuzzy prediction system that can consider and deal with the uncertainty of nonlinear data sufficiently. In the design procedures of the proposed system, HCBKA(Hierarchical Correlationship-Based K-means clustering Algorithm) was used to generate the accurate fuzzy rule base that can control output according to input efficiently, and the first-order difference method was applied to reflect various characteristics of the nonlinear data. Also, multiple prediction systems were designed to analyze the prediction tendencies of each difference data generated by the difference method. In addition, to enhance the prediction quality of the proposed system, an error compensation method was proposed and it compensated the prediction error of the systems suitably. Finally, the prediction performance of the proposed system was verified by simulating two typical time series examples.

Evaluating Distress Prediction Models for Food Service Franchise Industry (외식프랜차이즈기업 부실예측모형 예측력 평가)

  • KIM, Si-Joong
    • Journal of Distribution Science
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    • v.17 no.11
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    • pp.73-79
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    • 2019
  • Purpose: The purpose of this study was evaluated to compare the predictive power of distress prediction models by using discriminant analysis method and logit analysis method for food service franchise industry in Korea. Research design, data and methodology: Forty-six food service franchise industry with high sales volume in the 2017 were selected as the sample food service franchise industry for analysis. The fourteen financial ratios for analysis were calculated from the data in the 2017 statement of financial position and income statement of forty-six food service franchise industry in Korea. The fourteen financial ratios were used as sample data and analyzed by t-test. As a result seven statistically significant independent variables were chosen. The analysis method of the distress prediction model was performed by logit analysis and multiple discriminant analysis. Results: The difference between the average value of fourteen financial ratios of forty-six food service franchise industry was tested through t-test in order to extract variables that are classified as top-leveled and failure food service franchise industry among the financial ratios. As a result of the univariate test appears that the variables which differentiate the top-leveled food service franchise industry to failure food service industry are income to stockholders' equity, operating income to sales, current ratio, net income to assets, cash flows from operating activities, growth rate of operating income, and total assets turnover. The statistical significances of the seven financial ratio independent variables were also confirmed by logit analysis and discriminant analysis. Conclusions: The analysis results of the prediction accuracy of each distress prediction model in this study showed that the forecast accuracy of the prediction model by the discriminant analysis method was 84.8% and 89.1% by the logit analysis method, indicating that the logit analysis method has higher distress predictability than the discriminant analysis method. Comparing the previous distress prediction capability, which ranges from 75% to 85% by discriminant analysis and logit analysis, this study's prediction capacity, which is 84.8% in the discriminant analysis, and 89.1% in logit analysis, is found to belong to the range of previous study's prediction capacity range and is considered high number.

A Hilbert-Huang Transform Approach Combined with PCA for Predicting a Time Series

  • Park, Min-Jeong
    • The Korean Journal of Applied Statistics
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    • v.24 no.6
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    • pp.995-1006
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    • 2011
  • A time series can be decomposed into simple components with a multiscale method. Empirical mode decomposition(EMD) is a recently invented multiscale method in Huang et al. (1998). It is natural to apply a classical prediction method such a vector autoregressive(AR) model to the obtained simple components instead of the original time series; in addition, a prediction procedure combining a classical prediction model to EMD and Hilbert spectrum is proposed in Kim et al. (2008). In this paper, we suggest to adopt principal component analysis(PCA) to the prediction procedure that enables the efficient selection of input variables among obtained components by EMD. We discuss the utility of adopting PCA in the prediction procedure based on EMD and Hilbert spectrum and analyze the daily worm account data by the proposed PCA adopted prediction method.

A GA-based Binary Classification Method for Bankruptcy Prediction (도산예측을 위한 유전 알고리듬 기반 이진분류기법의 개발)

  • Min, Jae-H.;Jeong, Chul-Woo
    • Journal of the Korean Operations Research and Management Science Society
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    • v.33 no.2
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    • pp.1-16
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    • 2008
  • The purpose of this paper is to propose a new binary classification method for predicting corporate failure based on genetic algorithm, and to validate its prediction power through empirical analysis. Establishing virtual companies representing bankrupt companies and non-bankrupt ones respectively, the proposed method measures the similarity between the virtual companies and the subject for prediction, and classifies the subject into either bankrupt or non-bankrupt one. The values of the classification variables of the virtual companies and the weights of the variables are determined by the proper model to maximize the hit ratio of training data set using genetic algorithm. In order to test the validity of the proposed method, we compare its prediction accuracy with ones of other existing methods such as multi-discriminant analysis, logistic regression, decision tree, and artificial neural network, and it is shown that the binary classification method we propose in this paper can serve as a premising alternative to the existing methods for bankruptcy prediction.

Introduction to Gene Prediction Using HMM Algorithm

  • Kim, Keon-Kyun;Park, Eun-Sik
    • Journal of the Korean Data and Information Science Society
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    • v.18 no.2
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    • pp.489-506
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    • 2007
  • Gene structure prediction, which is to predict protein coding regions in a given nucleotide sequence, is the most important process in annotating genes and greatly affects gene analysis and genome annotation. As eukaryotic genes have more complicated structures in DNA sequences than those of prokaryotic genes, analysis programs for eukaryotic gene structure prediction have more diverse and more complicated computational models. There are Ab Initio method, Similarity-based method, and Ensemble method for gene prediction method for eukaryotic genes. Each Method use various algorithms. This paper introduce how to predict genes using HMM(Hidden Markov Model) algorithm and present the process of gene prediction with well-known gene prediction programs.

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