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Hidden Markov model based epileptic seizure detection using tunable Q wavelet transform 被引量:2
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作者 Deba Prasad Dash Maheshkumar H Kolekar 《The Journal of Biomedical Research》 CAS CSCD 2020年第3期170-179,共10页
Epilepsy is one of the most prevalent neurological disorders affecting 70 million people worldwide.The present work is focused on designing an efficient algorithm for automatic seizure detection by using electroenceph... Epilepsy is one of the most prevalent neurological disorders affecting 70 million people worldwide.The present work is focused on designing an efficient algorithm for automatic seizure detection by using electroencephalogram(EEG) as a noninvasive procedure to record neuronal activities in the brain.EEG signals' underlying dynamics are extracted to differentiate healthy and seizure EEG signals.Shannon entropy,collision entropy,transfer entropy,conditional probability,and Hjorth parameter features are extracted from subbands of tunable Q wavelet transform.Efficient decomposition level for different feature vector is selected using the Kruskal-Wallis test to achieve good classification.Different features are combined using the discriminant correlation analysis fusion technique to form a single fused feature vector.The accuracy of the proposed approach is higher for Q=2 and J=10.Transfer entropy is observed to be significant for different class combinations.Proposed approach achieved 100% accuracy in classifying healthy-seizure EEG signal using simple and robust features and hidden Markov model with less computation time.The proposed approach efficiency is evaluated in classifying seizure and non-seizure surface EEG signals.The system has achieved 96.87% accuracy in classifying surface seizure and nonseizure EEG segments using efficient features extracted from different J level. 展开更多
关键词 ELECTROENCEPHALOGRAM EPILEPSY SEIZURE tunable Q wavelet transform ENTROPY hidden markov model
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Improving Language Translation Using the Hidden Markov Model 被引量:1
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作者 Yunpeng Chang Xiaoliang Wang +2 位作者 Meihua Xue Yuzhen Liu Frank Jiang 《Computers, Materials & Continua》 SCIE EI 2021年第6期3921-3931,共11页
Translation software has become an important tool for communication between different languages.People’s requirements for translation are higher and higher,mainly reflected in people’s desire for barrier free cultur... Translation software has become an important tool for communication between different languages.People’s requirements for translation are higher and higher,mainly reflected in people’s desire for barrier free cultural exchange.With a large corpus,the performance of statistical machine translation based on words and phrases is limited due to the small size of modeling units.Previous statistical methods rely primarily on the size of corpus and number of its statistical results to avoid ambiguity in translation,ignoring context.To support the ongoing improvement of translation methods built upon deep learning,we propose a translation algorithm based on the Hidden Markov Model to improve the use of context in the process of translation.During translation,our Hidden Markov Model prediction chain selects a number of phrases with the highest result probability to form a sentence.The collection of all of the generated sentences forms a topic sequence.Using probabilities and article sequences determined from the training set,our method again applies the Hidden Markov Model to form the final translation to improve the context relevance in the process of translation.This algorithm improves the accuracy of translation,avoids the combination of invalid words,and enhances the readability and meaning of the resulting translation. 展开更多
关键词 Translation software hidden markov model context translation
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Robust Speech Recognition System Using Conventional and Hybrid Features of MFCC,LPCC,PLP,RASTA-PLP and Hidden Markov Model Classifier in Noisy Conditions 被引量:7
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作者 Veton Z.Kepuska Hussien A.Elharati 《Journal of Computer and Communications》 2015年第6期1-9,共9页
In recent years, the accuracy of speech recognition (SR) has been one of the most active areas of research. Despite that SR systems are working reasonably well in quiet conditions, they still suffer severe performance... In recent years, the accuracy of speech recognition (SR) has been one of the most active areas of research. Despite that SR systems are working reasonably well in quiet conditions, they still suffer severe performance degradation in noisy conditions or distorted channels. It is necessary to search for more robust feature extraction methods to gain better performance in adverse conditions. This paper investigates the performance of conventional and new hybrid speech feature extraction algorithms of Mel Frequency Cepstrum Coefficient (MFCC), Linear Prediction Coding Coefficient (LPCC), perceptual linear production (PLP), and RASTA-PLP in noisy conditions through using multivariate Hidden Markov Model (HMM) classifier. The behavior of the proposal system is evaluated using TIDIGIT human voice dataset corpora, recorded from 208 different adult speakers in both training and testing process. The theoretical basis for speech processing and classifier procedures were presented, and the recognition results were obtained based on word recognition rate. 展开更多
关键词 Speech Recognition Noisy Conditions Feature Extraction Mel-Frequency Cepstral Coefficients Linear Predictive Coding Coefficients Perceptual Linear Production RASTA-PLP Isolated Speech hidden markov model
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Applying the Hidden Markov Model to Analyze Urban Mobility Patterns: An Interdisciplinary Approach
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作者 LOO Becky P Y ZHANG Feiyang +2 位作者 HSIAO Janet H CHAN Antoni B LAN Hui 《Chinese Geographical Science》 SCIE CSCD 2021年第1期1-13,共13页
With the emergence of the Internet of Things(IoT), there has been a proliferation of urban studies using big data. Yet, another type of urban research innovations that involve interdisciplinary thinking and methods re... With the emergence of the Internet of Things(IoT), there has been a proliferation of urban studies using big data. Yet, another type of urban research innovations that involve interdisciplinary thinking and methods remains underdeveloped. This paper represents an attempt to adopt a Hidden Markov Model(HMM) toolbox developed in Computer Science for the analysis of eye movement patterns in Psychology to answer urban mobility questions in Geography. The main idea is that both people’s eye movements and travel behavior follow the stop-travel-stop pattern, which can be summarized using HMM. Methodological challenges were addressed by adjusting the HMM to analyze territory-wide travel survey data in Hong Kong, China. By using the adjusted toolbox to identify the activitytravel patterns of working adults in Hong Kong, two distinctive groups of balanced(38.4%) and work-oriented(61.6%) lifestyles were identified. With some notable exceptions, working adults living in the urban core were having a more work-oriented lifestyle. Those with a balanced lifestyle were having a relatively compact zone of non-work activities around their homes but a relatively long commuting distance. Furthermore, working females tend to spend more time at home than their counterparts, regardless of their marital status and lifestyle. Overall, this interdisciplinary research demonstrates an attempt to integrate spatial, temporal, and sequential information for understanding people’s behavior in urban mobility research. 展开更多
关键词 activity-travel pattern urban mobility activity sequences cluster analysis hidden markov model
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Fault Pattern Recognition Based on Hidden Markov Model
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作者 刘鑫 贾云献 +2 位作者 范智滕 田霞 张英波 《Journal of Donghua University(English Edition)》 EI CAS 2016年第2期280-283,共4页
Because performance parameters of gear have degradation,a method is proposed to recognize and analyze its faults using the hidden Markov model( HMM). In this method,firstly,the delayed correlation-envelope method is u... Because performance parameters of gear have degradation,a method is proposed to recognize and analyze its faults using the hidden Markov model( HMM). In this method,firstly,the delayed correlation-envelope method is used to extract features from vibration signals. Then,HMMs are trained respectively using data under normal condition,gear root crack condition and gear root breaking condition. Further,the trained HMMs are used in pattern recognition and model assessment. Finally,the results from standard HMM and the proposed method are compared, which shows that the proposed methodology is feasible and effective. 展开更多
关键词 hidden markov model(HMM) multiple-observations sequence fault pattern recognition
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Hidden Markov Models to Estimate the Lagged Effects of Weather on Stroke and Ischemic Heart Disease
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作者 Hiroshi Morimoto 《Applied Mathematics》 2016年第13期1415-1425,共12页
The links between low temperature and the incidence of disease have been studied by many researchers. What remains still unclear is the exact nature of the relation, especially the mechanism by which the change of wea... The links between low temperature and the incidence of disease have been studied by many researchers. What remains still unclear is the exact nature of the relation, especially the mechanism by which the change of weather effects on the onset of diseases. The existence of lag period between exposure to temperature and its effect on mortality may reflect the nature of the onset of diseases. Therefore, to assess lagged effects becomes potentially important. The most of studies on lags used the method by Lag-distributed Poisson Regression, and neglected extreme case as random noise to get correlations. In order to assess the lagged effect, we proposed a new approach, i.e., Hidden Markov Model by Self Organized Map (HMM by SOM) apart from well-known regression models. HMM by SOM includes the randomness in its nature and encompasses the extreme cases which were neglected by auto-regression models. The daily data of the number of patients transported by ambulance in Nagoya, Japan, were used. SOM was carried out to classify the meteorological elements into six classes. These classes were used as “states” of HMM. HMM was used to describe a background process which might produce the time series of the incidence of diseases. The background process was considered to change randomly weather states, classified by SOM. We estimated the lagged effects of weather change on the onset of both cerebral infarction and ischemic heart disease. This fact is potentially important in that if one could trace a path in the chain of events leading from temperature change to death, one might be able to prevent it and avert the fatal outcome. 展开更多
关键词 hidden markov model Self Organized Map STROKE Cerebral Infarction Ischemic Heart Disease
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Fully Polarimetric Land Cover Classification Based on Hidden Markov Models Trained with Multiple Observations
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作者 Konstantinos Karachristos Georgia Koukiou Vassilis Anastassopoulos 《Advances in Remote Sensing》 2021年第3期102-114,共13页
A land cover classification procedure is presented utilizing the information content of fully polarimetric SAR images. The Cameron coherent target decomposition (CTD) is employed to characterize each pixel, using a se... A land cover classification procedure is presented utilizing the information content of fully polarimetric SAR images. The Cameron coherent target decomposition (CTD) is employed to characterize each pixel, using a set of canonical scattering mechanisms in order to describe the physical properties of the scatterer. The novelty of the proposed classification approach lies on the use of Hidden Markov Models (HMM) to uniquely characterize each type of land cover. The motivation to this approach is the investigation of the alternation between scattering mechanisms from SAR pixel to pixel. Depending </span><span style="font-family:Verdana;">on the observations-scattering mechanisms and exploiting the transitions </span><span style="font-family:Verdana;">between the scattering mechanisms we decide upon the HMM-land cover type. The classification process is based on the likelihood of observation sequences </span><span style="font-family:Verdana;">been evaluated by each model. The performance of the classification ap</span><span style="font-family:Verdana;">proach is assessed my means of fully polarimetric SLC SAR data from the broader </span><span style="font-family:Verdana;">area of Vancouver, Canada and was found satisfactory, reaching a success</span><span style="font-family:Verdana;"> from 87% to over 99%. 展开更多
关键词 Fully Polarimetric SAR Coherent Decomposition Land Cover Classification hidden markov models Remote Sensing
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Morpho-Syntactic Tagging of Text in “Baoule” Language Based on Hidden Markov Models (HMM)
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作者 Hyacinthe Konan Bi Tra Gooré +1 位作者 Raymond Gbégbé Olivier Asseu 《Journal of Software Engineering and Applications》 2016年第10期516-523,共9页
The label text is a very important tool for the automatic processing of language. It is used in several applications such as morphological and syntactic text analysis, index-ing, retrieval, finished networks determini... The label text is a very important tool for the automatic processing of language. It is used in several applications such as morphological and syntactic text analysis, index-ing, retrieval, finished networks deterministic (in which all combinations of words that are accepted by the grammar are listed) or by statistical grammars (e.g., an n-gram in which the probabilities of sequences of n words in a specific order are given), etc. In this article, we developed a morphosyntactic labeling system language “Baoule” using hidden Markov models. This will allow us to build a tagged reference corpus and rep-resent major grammatical rules faced “Baoule” language in general. To estimate the parameters of this model, we used a training corpus manually labeled using a set of morpho-syntactic labels. We then proceed to an improvement of the system through the re-estimation procedure parameters of this model. 展开更多
关键词 CORPUS the Set of Tags the Morpho-Syntactic Tagging “Baoule” Language hidden markov model
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Hidden Markov Models and Self-Organizing Maps Applied to Stroke Incidence
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作者 Hiroshi Morimoto 《Open Journal of Applied Sciences》 2016年第3期158-168,共11页
Several studies were devoted to investigate the effects of meteorological factors on the occurrence of stroke. Regression models had been mostly used to assess the correlation between weather and stroke incidence. How... Several studies were devoted to investigate the effects of meteorological factors on the occurrence of stroke. Regression models had been mostly used to assess the correlation between weather and stroke incidence. However, these methods could not describe the process proceeding in the back-ground of stroke incidence. The purpose of this study was to provide a new approach based on Hidden Markov Models (HMMs) and self-organizing maps (SOM), interpreting the background from the viewpoint of weather variability. Based on meteorological data, SOM was performed to classify weather patterns. Using these classes by SOM as randomly changing “states”, our Hidden Markov Models were constructed with “observation data” that were extracted from the daily data of emergency transport at Nagoya City in Japan. We showed that SOM was an effective method to get weather patterns that would serve as “states” of Hidden Markov Models. Our Hidden Markov Models provided effective models to clarify background process for stroke incidence. The effectiveness of these Hidden Markov Models was estimated by stochastic test for root mean square errors (RMSE). “HMMs with states by SOM” would serve as a description of the background process of stroke incidence and were useful to show the influence of weather on stroke onset. This finding will contribute to an improvement of our understanding for links between weather variability and stroke incidence. 展开更多
关键词 hidden markov model Self Organized Maps STROKE Cerebral Infarction
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Application of Hidden Markov Models in Stock Forecasting
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作者 Menghan Yu Panji Wang Tong Wang 《Proceedings of Business and Economic Studies》 2022年第6期14-21,共8页
In this paper,we tested our methodology on the stocks of four representative companies:Apple,Comcast Corporation(CMCST),Google,and Qualcomm.We compared their performance to several stocks using the hidden Markov model... In this paper,we tested our methodology on the stocks of four representative companies:Apple,Comcast Corporation(CMCST),Google,and Qualcomm.We compared their performance to several stocks using the hidden Markov model(HMM)and forecasts using mean absolute percentage error(MAPE).For simplicity,we considered four main features in these stocks:open,close,high,and low prices.When using the HMM for forecasting,the HMM has the best prediction for the daily low stock price and daily high stock price of Apple and CMCST,respectively.By calculating the MAPE for the four data sets of Google,the close price has the largest prediction error,while the open price has the smallest prediction error.The HMM has the largest prediction error and the smallest prediction error for Qualcomm’s daily low stock price and daily high stock price,respectively. 展开更多
关键词 hidden markov model Mean absolute error Stock market
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On-line Fault Diagnosis in Industrial Processes Using Variable Moving Window and Hidden Markov Model 被引量:9
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作者 周韶园 谢磊 王树青 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第3期388-395,共8页
An integrated framework is presented to represent and classify process data for on-line identifying abnormal operating conditions. It is based on pattern recognition principles and consists of a feature extraction ste... An integrated framework is presented to represent and classify process data for on-line identifying abnormal operating conditions. It is based on pattern recognition principles and consists of a feature extraction step, by which wavelet transform and principal component analysis are used to capture the inherent characteristics from process measurements, followed by a similarity assessment step using hidden Markov model (HMM) for pattern comparison. In most previous cases, a fixed-length moving window was employed to track dynamic data, and often failed to capture enough information for each fault and sometimes even deteriorated the diagnostic performance. A variable moving window, the length of which is modified with time, is introduced in this paper and case studies on the Tennessee Eastman process illustrate the potential of the proposed method. 展开更多
关键词 隐马尔可夫模型 生产过程 在线诊断 人工神经网络 微波传播
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FAULT DIAGNOSIS APPROACH BASED ON HIDDEN MARKOV MODEL AND SUPPORT VECTOR MACHINE 被引量:4
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作者 LIU Guanjun LIU Xinmin QIU Jing HU Niaoqing 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第5期92-95,共4页
瞄准解决这些问题在差错诊断学习机器,一条诊断途径基于隐藏的 Markov 模型被建议(唔) 并且支持向量机器(SVM ) 。唔通常描述 intra 班措施很好并且擅长处理连续动态信号。SVM 有效地表示年级之间的差别并且让完成式分类能力。这条途... 瞄准解决这些问题在差错诊断学习机器,一条诊断途径基于隐藏的 Markov 模型被建议(唔) 并且支持向量机器(SVM ) 。唔通常描述 intra 班措施很好并且擅长处理连续动态信号。SVM 有效地表示年级之间的差别并且让完成式分类能力。这条途径在优点上被造唔并且 SVM。然后,实验在一架直升飞机的传播系统被做。与从颤动信号提取的特征上档框,这 HMM-SVM 基于诊断途径被训练并且过去常监视并且诊断 gearbox 的差错。结果证明这个方法比唔基于好、基于 SVM 与小训练样品在更高诊断的精确性诊断方法。 展开更多
关键词 模型设计 支持矢量 机械诊断 技术性能
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Improved hidden Markov model for speech recognition and POS tagging 被引量:4
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作者 袁里驰 《Journal of Central South University》 SCIE EI CAS 2012年第2期511-516,共6页
In order to overcome defects of the classical hidden Markov model (HMM), Markov family model (MFM), a new statistical model was proposed. Markov family model was applied to speech recognition and natural language proc... In order to overcome defects of the classical hidden Markov model (HMM), Markov family model (MFM), a new statistical model was proposed. Markov family model was applied to speech recognition and natural language processing. The speaker independently continuous speech recognition experiments and the part-of-speech tagging experiments show that Markov family model has higher performance than hidden Markov model. The precision is enhanced from 94.642% to 96.214% in the part-of-speech tagging experiments, and the work rate is reduced by 11.9% in the speech recognition experiments with respect to HMM baseline system. 展开更多
关键词 隐马尔可夫模型 连续语音识别 词性标注 自然语言处理 统计模型 基线系统 HMM 实验
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An Intrusion Detection Method Based on Hierarchical Hidden Markov Models 被引量:2
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作者 JIA Chunfu YANG Feng 《Wuhan University Journal of Natural Sciences》 CAS 2007年第1期135-138,共4页
This paper presents an anomaly detection approach to detect intrusions into computer systems. In this approach, a hier- archical hidden Markov model (HHMM) is used to represent a temporal profile of normal behavior in... This paper presents an anomaly detection approach to detect intrusions into computer systems. In this approach, a hier- archical hidden Markov model (HHMM) is used to represent a temporal profile of normal behavior in a computer system. The HHMM of the norm profile is learned from historic data of the system’s normal behavior. The observed behavior of the system is analyzed to infer the probability that the HHMM of the norm pro- file supports the observed behavior. A low probability of support indicates an anomalous behavior that may result from intrusive activities. The model was implemented and tested on the UNIX system call sequences collected by the University of New Mexico group. The testing results showed that the model can clearly iden- tify the anomaly activities and has a better performance than hid- den Markov model. 展开更多
关键词 计算机 网络技术 隐马尔可夫模型 安全技术
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2D-HIDDEN MARKOV MODEL FEATURE EXTRACTION STRATEGY OF ROTATING MACHINERY FAULT DIAGNOSIS 被引量:1
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作者 YE Dapeng DING Qiquan WU Zhaotong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2006年第1期156-158,共3页
一个新特征抽取方法基于 2D 兽皮 Markov 模型(唔) 被建议。同时,时间索引和频率索引被介绍代表新特征。新特征抽取策略被从 Bentlyrotor 实验系统收集了的试验性的数据测试。结果证明这方法论是很有效的在转子加速功课提取颤动信号的... 一个新特征抽取方法基于 2D 兽皮 Markov 模型(唔) 被建议。同时,时间索引和频率索引被介绍代表新特征。新特征抽取策略被从 Bentlyrotor 实验系统收集了的试验性的数据测试。结果证明这方法论是很有效的在转子加速功课提取颤动信号的特征并且以后能被扩大到 othernon 静止的信号分析地。 展开更多
关键词 转动机械 HMM 二维隐藏马尔科夫模型 特征提取 故障诊断
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Fault diagnosis method for an Aeroengine Based on Independent Component Analysis and the Discrete Hidden Markov Model 被引量:1
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作者 MA Jian-cang ZENG Yuan 《International Journal of Plant Engineering and Management》 2009年第4期193-201,共9页
The vibration signals of an aeroengine are a very important information source for fault diagnosis and condition monitoring. Considering the nonstationarity and low repeatability of the vibration signals, it is necess... The vibration signals of an aeroengine are a very important information source for fault diagnosis and condition monitoring. Considering the nonstationarity and low repeatability of the vibration signals, it is necessary to find a corresponding method for feature extraction and fault recognition. In this paper, based on Independent Component Analysis (ICA) and the Discrete Hidden Markov Model (DHMM), a new fault diagnosis approach named ICA-DHMM is proposed. In this method, ICA separates the source signals from the mixed vibration signals and then extracts features from them, DHMM works as a classifier to recognize the conditions of the aeroengine. Compared with the DHMM, which use the amplitude spectrum of mixed signals as feature parameters, experimental results show this method has higher diagnosis accuracy. 展开更多
关键词 故障诊断方法 隐马尔可夫模型 航空发动机 独立成分分析 离散 隐马尔柯夫模型 振动信号 独立分量分析
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Discrete channel modelling based on genetic algorithm and simulated annealing for training hidden Markov model
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作者 赵知劲 郑仕链 +1 位作者 徐春云 孔宪正 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第6期1619-1623,共5页
关键词 隐马尔可夫模型 离散信道模型 遗传算法 模拟退火
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MANDARIN TONE RECOGNITION BASED ON WAVELET TRANSFORM AND HIDDEN MARKOV MODELING
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作者 Cheng Jun Yi Kechu Li Bingbing (National Key Laboratory on ISN, Xid/an University, Xi’an 710071) 《Journal of Electronics(China)》 2000年第1期1-8,共8页
This paper presents a method of tone recognition for Mandarin speech by using combination of wavelet transform and hidden Markov modeling techniques. A pitch detector based on singularity detection and multi-resolutio... This paper presents a method of tone recognition for Mandarin speech by using combination of wavelet transform and hidden Markov modeling techniques. A pitch detector based on singularity detection and multi-resolution analysis of wavelet transform is employed for estimation of pitch periods, and hidden Markov modeling with partition Gaussian mixtures probability density function is used for the tone recognition. The algorithm can provide recognition accuracy of 97.22% and 94.47% for speaker-dependent and speaker-independent tone recognition, respectively. 展开更多
关键词 PITCH detection TONE recognition WAVELET TRANSFORM hidden markov model
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An Intelligent Web Pre-fetching Based on Hidden Markov Model
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作者 许欢庆 金鑫 《Journal of Donghua University(English Edition)》 EI CAS 2004年第1期46-50,共5页
Web pre-fetching is one of the most popular strategies,which are proposed for reducing the perceived access delay and improving the service quality of web server. In this paper, we present a pre-fetching model based o... Web pre-fetching is one of the most popular strategies,which are proposed for reducing the perceived access delay and improving the service quality of web server. In this paper, we present a pre-fetching model based on the hidden Markov model, which mines the latent information requirement concepts that the user's access path contains and makes semantic-based pre-fetching decisions.Experimental results show that our scheme has better predictive pre-fetching precision. 展开更多
关键词 隐藏马尔可夫模型 智能网 信息需求概念 网络预先存取 带宽
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Video object's behavior analyzing based on motion history image and hidden markov model
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作者 孟繁锋 《High Technology Letters》 EI CAS 2009年第3期319-324,共6页
A novel method was proposed,which extracted video object' s track and analyzed video object's be-havior.Firstly,this method tracked the video object based on motion history image,and obtained the co-ordinate-b... A novel method was proposed,which extracted video object' s track and analyzed video object's be-havior.Firstly,this method tracked the video object based on motion history image,and obtained the co-ordinate-based track sequence and orientation-based track sequence of the video object.Then the pro-posed hidden markov model(HMM)based algorithm was used to analyze the behavior of video object withthe track sequence as input.Experimental results on traffic object show that this method can achieve thestatistics of a mass of traffic objects'behavior efficiently,can acquire the reasonable velocity behaviorcurve of traffic object,and can recognize traffic object's various behaviors accurately.It provides a basefor further research on video obiect behavior. 展开更多
关键词 隐马尔可夫模型 视频对象 行为 形象 历史 运动 基础 交通速度
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