• Title, Summary, Keyword: Error Correction Model

Search Result 511, Processing Time 0.045 seconds

Improvement of flood simulation accuracy based on the combination of hydraulic model and error correction model

  • Li, Li;Jun, Kyung Soo
    • Proceedings of the Korea Water Resources Association Conference
    • /
    • /
    • pp.258-258
    • /
    • 2018
  • In this study, a hydraulic flow model and an error correction model are combined to improve the flood simulation accuracy. First, the hydraulic flow model is calibrated by optimizing the Manning's roughness coefficient that considers spatial and temporal variability. Then, an error correction model were used to correct the systematic errors of the calibrated hydraulic model. The error correction model is developed using Artificial Neural Networks (ANNs) that can estimate the systematic simulation errors of the hydraulic model by considering some state variables as inputs. The input variables are selected using parital mutual information (PMI) technique. It was found that the calibrated hydraulic model can simulate flood water levels with good accuracy. Then, the accuracy of estimated flood levels is improved further by using the error correction model. The method proposed in this study can be used to the flood control and water resources management as it can provide accurate water level eatimation.

  • PDF

Improved Statistical Language Model for Context-sensitive Spelling Error Candidates (문맥의존 철자오류 후보 생성을 위한 통계적 언어모형 개선)

  • Lee, Jung-Hun;Kim, Minho;Kwon, Hyuk-Chul
    • Journal of Korea Multimedia Society
    • /
    • v.20 no.2
    • /
    • pp.371-381
    • /
    • 2017
  • The performance of the statistical context-sensitive spelling error correction depends on the quality and quantity of the data for statistical language model. In general, the size and quality of data in a statistical language model are proportional. However, as the amount of data increases, the processing speed becomes slower and storage space also takes up a lot. We suggest the improved statistical language model to solve this problem. And we propose an effective spelling error candidate generation method based on a new statistical language model. The proposed statistical model and the correction method based on it improve the performance of the spelling error correction and processing speed.

A Spelling Error Correction Model in Korean Using a Correction Dictionary and a Newspaper Corpus (교정사전과 신문기사 말뭉치를 이용한 한국어 철자 오류 교정 모델)

  • Lee, Se-Hee;Kim, Hark-Soo
    • The KIPS Transactions:PartB
    • /
    • v.16B no.5
    • /
    • pp.427-434
    • /
    • 2009
  • With the rapid evolution of the Internet and mobile environments, text including spelling errors such as newly-coined words and abbreviated words are widely used. These spelling errors make it difficult to develop NLP (natural language processing) applications because they decrease the readability of texts. To resolve this problem, we propose a spelling error correction model using a spelling error correction dictionary and a newspaper corpus. The proposed model has the advantage that the cost of data construction are not high because it uses a newspaper corpus, which we can easily obtain, as a training corpus. In addition, the proposed model has an advantage that additional external modules such as a morphological analyzer and a word-spacing error correction system are not required because it uses a simple string matching method based on a correction dictionary. In the experiments with a newspaper corpus and a short message corpus collected from real mobile phones, the proposed model has been shown good performances (a miss-correction rate of 7.3%, a F1-measure of 97.3%, and a false positive rate of 1.1%) in the various evaluation measures.

The Relationship between World Oil Price and Consummer Price Index in Korea (국제유가와 소비자물가의 변동)

  • Kim, Youngduk
    • Environmental and Resource Economics Review
    • /
    • v.9 no.2
    • /
    • pp.373-391
    • /
    • 2000
  • This paper investigates the existence of a long-run relationship between world oil price and consumer price index for Korea during 1983~1999. The cointegration and error correction modelling approaches have been applied. Empirical results suggest that there exists a long-run relationship among world oil prices. consumer prices, M2 and a production gap variable. The dynamic behavior of the relationship has been investigated by estimating a error correction model, in which the error correction term have been found significant. The error correction model has also been found to be robust as it satisfy almost all relevant diagnostic tests.

  • PDF

Performance Analysis of Low-Order Surface Methods for Compact Network RTK: Case Study

  • Song, Junesol;Park, Byungwoon;Kee, Changdon
    • Journal of Positioning, Navigation, and Timing
    • /
    • v.4 no.1
    • /
    • pp.33-41
    • /
    • 2015
  • Compact Network Real-Time Kinematic (RTK) is a method that combines compact RTK and network RTK, and it can effectively reduce the time and spatial de-correlation errors. A network RTK user receives multiple correction information generated from reference stations that constitute a network, calculates correction information that is appropriate for one's own position through a proper combination method, and uses the information for the estimation of the position. This combination method is classified depending on the method for modeling the GPS error elements included in correction information, and the user position accuracy is affected by the accuracy of this modeling. Among the GPS error elements included in correction information, tropospheric delay is generally eliminated using a tropospheric model, and a combination method is then applied. In the case of a tropospheric model, the estimation accuracy varies depending on the meteorological condition, and thus eliminating the tropospheric delay of correction information using a tropospheric model is limited to a certain extent. In this study, correction information modeling accuracy performances were compared focusing on the Low-Order Surface Model (LSM), which models the GPS error elements included in correction information using a low-order surface, and a modified LSM method that considers tropospheric delay characteristics depending on altitude. Both of the two methods model GPS error elements in relation to altitude, but the second method reflects the characteristics of actual tropospheric delay depending on altitude. In this study, the final residual errors of user measurements were compared and analyzed using the correction information generated by the various methods mentioned above. For the performance comparison and analysis, various GPS actual measurement data were collected. The results indicated that the modified LSM method that considers actual tropospheric characteristics showed improved performance in terms of user measurement residual error and position domain residual error.

EFFICIENT ESTIMATION OF THE COINTEGRATING VECTOR IN ERROR CORRECTION MODELS WITH STATIONARY COVARIATES

  • Seo, Byeong-Seon
    • Journal of the Korean Statistical Society
    • /
    • v.34 no.4
    • /
    • pp.345-366
    • /
    • 2005
  • This paper considers the cointegrating vector estimator in the error correction model with stationary covariates, which combines the stationary vector autoregressive model and the nonstationary error correction model. The cointegrating vector estimator is shown to follow the locally asymptotically mixed normal distribution. The variance of the estimator depends on the co­variate effect of stationary regressors, and the asymptotic efficiency improves as the magnitude of the covariate effect increases. An economic application of the money demand equation is provided.

Rule-based Speech Recognition Error Correction for Mobile Environment (모바일 환경을 고려한 규칙기반 음성인식 오류교정)

  • Kim, Jin-Hyung;Park, So-Young
    • Journal of the Korea Society of Computer and Information
    • /
    • v.17 no.10
    • /
    • pp.25-33
    • /
    • 2012
  • In this paper, we propose a rule-based model to correct errors in a speech recognition result in the mobile device environment. The proposed model considers the mobile device environment with limited resources such as processing time and memory, as follows. In order to minimize the error correction processing time, the proposed model removes some processing steps such as morphological analysis and the composition and decomposition of syllable. Also, the proposed model utilizes the longest match rule selection method to generate one error correction candidate per point, assumed that an error occurs. For the purpose of deploying memory resource, the proposed model uses neither the Eojeol dictionary nor the morphological analyzer, and stores a combined rule list without any classification. Considering the modification and maintenance of the proposed model, the error correction rules are automatically extracted from a training corpus. Experimental results show that the proposed model improves 5.27% on the precision and 5.60% on the recall based on Eojoel unit for the speech recognition result.

A New Correction Algorithm of Servo Track Writing Error in High-Density Disk Drives (고밀도 디스크 드라이브의 서보트랙 기록오차 보정 알고리즘)

  • 강창익;김창환
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.9 no.4
    • /
    • pp.284-295
    • /
    • 2003
  • The servo tracks of disk drives are constructed at the time of manufacture with the equipment of servo track writer. Because of the imperfection of servo track writer, disk vibrations and head fluctuations during servo track writing process, the constructed servo tracks might deviate from perfect circles and take eccentric shapes. The servo track writing error should be corrected because it might cause interference with adjacent tracks and irrecoverable operation error of disk drives. The servo track writing error is repeated every disk rotation and so is periodic time function. In this paper, we propose a new correction algorithm of servo track writing error based on iterative teaming approach. Our correction algorithm can learn iteratively the servo track writing error as accurately as is desired. Furthermore, our algorithm is robust to system model errors, is computationally simple, and has fast convergence rate. In order to demonstrate the generality and practical use of our work, we present the convergence analysis of our correction algorithm and some simulation results.

Dynamic analysis of financial market contagion (금융시장 전염 동적 검정)

  • Lee, Hee Soo;Kim, Tae Yoon
    • The Korean Journal of Applied Statistics
    • /
    • v.29 no.1
    • /
    • pp.75-83
    • /
    • 2016
  • We propose methodology to analyze the dynamic mechanisms of financial market contagion under market integration using a biological contagion analytical approach. We employ U-statistic to measure market integration, and a dynamic model based on an error correction mechanism (single equation error correction model) and latent factor model to examine market contagion. We also use quantile regression and Wald-Wolfowitz runs test to test market contagion. This methodology is designed to effectively handle heteroscedasticity and correlated errors. Our simulation results show that the single equation error correction model fits well with the linear regression model with a stationary predictor and correlated errors.

Error Correction Methode Improve System using Out-of Vocabulary Rejection (미등록어 거절을 이용한 오류 보정 방법 개선 시스템)

  • Ahn, Chan-Shik;Oh, Sang-Yeob
    • Journal of Digital Convergence
    • /
    • v.10 no.8
    • /
    • pp.173-178
    • /
    • 2012
  • In the generated model for the recognition vocabulary, tri-phones which is not make preparations are produced. Therefore this model does not generate an initial estimate of parameter words, and the system can not configure the model appear as disadvantages. As a result, the sophistication of the Gaussian model is fall will degrade recognition. In this system, we propose the error correction system using out-of vocabulary rejection algorithm. When the systems are creating a vocabulary recognition model, recognition rates are improved to refuse the vocabulary which is not registered. In addition, this system is seized the lexical analysis and meaning using probability distributions, and this system deactivates the string before phoneme change was applied. System analysis determine the rate of error correction using phoneme similarity rate and reliability, system performance comparison as a result of error correction rate improve represent 2.8% by method using error patterns, fault patterns, meaning patterns.