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Bayesian Estimation and Hierarchical Bayesian Estimation of Zero-failure Data 被引量:7
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作者 韩明 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第1期65-70,共6页
The zero_failure data research is a new field in the recent years, but it is required urgently in practical projects, so the work has more theory and practical values. In this paper, for zero_failure data (t i,n i... The zero_failure data research is a new field in the recent years, but it is required urgently in practical projects, so the work has more theory and practical values. In this paper, for zero_failure data (t i,n i) at moment t i , if the prior distribution of the failure probability p i=p{T【t i} is quasi_exponential distribution, the author gives the p i Bayesian estimation and hierarchical Bayesian estimation and the reliability under zero_failure date condition is also obtained. 展开更多
关键词 RELIABILITY zero_failure data failure probability Bayesian estimation hierarchical Bayesian estimaiton
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Network pharmacology-based exploration of molecular mechanisms underlying therapeutic effects of Jianpi Huatan Quyu recipe on chronic heart failure with spleen Qi deficiency syndrome
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作者 Si-Qi Li Dong-Yu Min +7 位作者 Jun-Wen Jiang Xiao-Ying Li Xu-Na Yang Wen-Bo Gu Jia-Hui Jiang Li-Hao Chen Han Nan Ze-Yu Chen 《World Journal of Cardiology》 2024年第7期422-435,共14页
BACKGROUND Chronic heart failure is a complex clinical syndrome.The Chinese herbal compound preparation Jianpi Huatan Quyu recipe has been used to treat chronic heart failure;however,the underlying molecular mechanism... BACKGROUND Chronic heart failure is a complex clinical syndrome.The Chinese herbal compound preparation Jianpi Huatan Quyu recipe has been used to treat chronic heart failure;however,the underlying molecular mechanism is still not clear.AIM To identify the effective active ingredients of Jianpi Huatan Quyu recipe and explore its molecular mechanism in the treatment of chronic heart failure.METHODS The effective active ingredients of eight herbs composing Jianpi Huatan Quyu recipe were identified using the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform.The target genes of chronic heart failure were searched in the Genecards database.The target proteins of active ingredients were mapped to chronic heart failure target genes to obtain the common drugdisease targets,which were then used to construct a key chemical componenttarget network using Cytoscape 3.7.2 software.The protein-protein interaction network was constructed using the String database.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were performed through the Metascape database.Finally,our previously published relevant articles were searched to verify the results obtained via network pharmacology.RESULTS A total of 227 effective active ingredients for Jianpi Huatan Quyu recipe were identified,of which quercetin,kaempferol,7-methoxy-2-methyl isoflavone,formononetin,and isorhamnetin may be key active ingredients and involved in the therapeutic effects of TCM by acting on STAT3,MAPK3,AKT1,JUN,MAPK1,TP53,TNF,HSP90AA1,p65,MAPK8,MAPK14,IL6,EGFR,EDN1,FOS,and other proteins.The pathways identified by KEGG enrichment analysis include pathways in cancer,IL-17 signaling pathway,PI3K-Akt signaling pathway,HIF-1 signaling pathway,calcium signaling pathway,cAMP signaling pathway,NF-kappaB signaling pathway,AMPK signaling pathway,etc.Previous studies on Jianpi Huatan Quyu recipe suggested that this Chinese compound preparation can regulate the TNF-α,IL-6,MAPK,cAMP,and AMPK pathways to affect the mitochondrial structure of myocardial cells,oxidative stress,and energy metabolism,thus achieving the therapeutic effects on chronic heart failure.CONCLUSION The Chinese medicine compound preparation Jianpi Huatan Quyu recipe exerts therapeutic effects on chronic heart failure possibly by influencing the mitochondrial structure of cardiomyocytes,oxidative stress,energy metabolism,and other processes.Future studies are warranted to investigate the role of the IL-17 signaling pathway,PI3K-Akt signaling pathway,HIF-1 signaling pathway,and other pathways in mediating the therapeutic effects of Jianpi Huatan Quyu recipe on chronic heart failure. 展开更多
关键词 Jianpi Huatan Quyu recipe Traditional Chinese medicine Chronic heart failure data mining Network pharmacology BIOINFORMATICS Spleen Qi deficiency syndrome
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Remaining useful life prediction based on nonlinear random coefficient regression model with fusing failure time data 被引量:1
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作者 WANG Fengfei TANG Shengjin +3 位作者 SUN Xiaoyan LI Liang YU Chuanqiang SI Xiaosheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第1期247-258,共12页
Remaining useful life(RUL) prediction is one of the most crucial elements in prognostics and health management(PHM). Aiming at the imperfect prior information, this paper proposes an RUL prediction method based on a n... Remaining useful life(RUL) prediction is one of the most crucial elements in prognostics and health management(PHM). Aiming at the imperfect prior information, this paper proposes an RUL prediction method based on a nonlinear random coefficient regression(RCR) model with fusing failure time data.Firstly, some interesting natures of parameters estimation based on the nonlinear RCR model are given. Based on these natures,the failure time data can be fused as the prior information reasonably. Specifically, the fixed parameters are calculated by the field degradation data of the evaluated equipment and the prior information of random coefficient is estimated with fusing the failure time data of congeneric equipment. Then, the prior information of the random coefficient is updated online under the Bayesian framework, the probability density function(PDF) of the RUL with considering the limitation of the failure threshold is performed. Finally, two case studies are used for experimental verification. Compared with the traditional Bayesian method, the proposed method can effectively reduce the influence of imperfect prior information and improve the accuracy of RUL prediction. 展开更多
关键词 remaining useful life(RUL)prediction imperfect prior information failure time data NONLINEAR random coefficient regression(RCR)model
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Machine Learning and Synthetic Minority Oversampling Techniques for Imbalanced Data: Improving Machine Failure Prediction
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作者 Yap Bee Wah Azlan Ismail +4 位作者 Nur Niswah Naslina Azid Jafreezal Jaafar Izzatdin Abdul Aziz Mohd Hilmi Hasan Jasni Mohamad Zain 《Computers, Materials & Continua》 SCIE EI 2023年第6期4821-4841,共21页
Prediction of machine failure is challenging as the dataset is often imbalanced with a low failure rate.The common approach to han-dle classification involving imbalanced data is to balance the data using a sampling a... Prediction of machine failure is challenging as the dataset is often imbalanced with a low failure rate.The common approach to han-dle classification involving imbalanced data is to balance the data using a sampling approach such as random undersampling,random oversampling,or Synthetic Minority Oversampling Technique(SMOTE)algorithms.This paper compared the classification performance of three popular classifiers(Logistic Regression,Gaussian Naïve Bayes,and Support Vector Machine)in predicting machine failure in the Oil and Gas industry.The original machine failure dataset consists of 20,473 hourly data and is imbalanced with 19945(97%)‘non-failure’and 528(3%)‘failure data’.The three independent variables to predict machine failure were pressure indicator,flow indicator,and level indicator.The accuracy of the classifiers is very high and close to 100%,but the sensitivity of all classifiers using the original dataset was close to zero.The performance of the three classifiers was then evaluated for data with different imbalance rates(10%to 50%)generated from the original data using SMOTE,SMOTE-Support Vector Machine(SMOTE-SVM)and SMOTE-Edited Nearest Neighbour(SMOTE-ENN).The classifiers were evaluated based on improvement in sensitivity and F-measure.Results showed that the sensitivity of all classifiers increases as the imbalance rate increases.SVM with radial basis function(RBF)kernel has the highest sensitivity when data is balanced(50:50)using SMOTE(Sensitivitytest=0.5686,Ftest=0.6927)compared to Naïve Bayes(Sensitivitytest=0.4033,Ftest=0.6218)and Logistic Regression(Sensitivitytest=0.4194,Ftest=0.621).Overall,the Gaussian Naïve Bayes model consistently improves sensitivity and F-measure as the imbalance ratio increases,but the sensitivity is below 50%.The classifiers performed better when data was balanced using SMOTE-SVM compared to SMOTE and SMOTE-ENN. 展开更多
关键词 Machine failure machine learning imbalanced data SMOTE CLASSIFICATION
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Comparison of Estimated Cycle Split Failures from High-Resolution Controller Event and Connected Vehicle Trajectory Data
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作者 Saumabha Gayen Enrique D. Saldivar-Carranza Darcy M. Bullock 《Journal of Transportation Technologies》 2023年第4期689-707,共19页
Current traffic signal split failure (SF) estimations derived from high-resolution controller event data rely on detector occupancy ratios and preset thresholds. The reliability of these techniques depends on the sele... Current traffic signal split failure (SF) estimations derived from high-resolution controller event data rely on detector occupancy ratios and preset thresholds. The reliability of these techniques depends on the selected thresholds, detector lengths, and vehicle arrival patterns. Connected vehicle (CV) trajectory data can more definitively show when a vehicle split fails by evaluating the number of stops it experiences as it approaches an intersection, but it has limited market penetration. This paper compares cycle-by-cycle SF estimations from both high-resolution controller event data and CV trajectory data, and evaluates the effect of data aggregation on SF agreement between the two techniques. Results indicate that, in general, split failure events identified from CV data are likely to also be captured from high-resolution data, but split failure events identified from high-resolution data are less likely to be captured from CV data. This is due to the CV market penetration rate (MPR) of ~5% being too low to capture representative data for every controller cycle. However, data aggregation can increase the ratio in which CV data captures split failure events. For example, day-of-week data aggregation increased the percentage of split failures identified with high-resolution data that were also captured with CV data from 35% to 56%. It is recommended that aggregated CV data be used to estimate SF as it provides conservative and actionable results without the limitations of intersection and detector configuration. As the CV MPR increases, the accuracy of CV-based SF estimation will also improve. 展开更多
关键词 Split failure Connected Vehicle Detector Traffic Signal Performance Measures Trajectory data
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Processing for Zero-Failure Data of the Products 被引量:3
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作者 Han Ming 1,2 & Cui Yuping 3 (1. Department of Statistics, Renmin University of China, Beijing 100872, P.R. China 2. Department of Mathematics, Zhejiang Ocean University, Zhoushan 316004, P.R. China 3. Department of Machine and Electron, Dongbei Power College, Jilin 130012, P.R. China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2002年第3期91-97,共7页
In this paper, an estimation method for reliability parameter in the case of zero-failuare data-synthetic estimation method is given. For zero-failure data of double-parameter exponential distribution, a hierarchical ... In this paper, an estimation method for reliability parameter in the case of zero-failuare data-synthetic estimation method is given. For zero-failure data of double-parameter exponential distribution, a hierarchical Bayesian estimation of the failure probability is presented. After failure information is introduced, hierarchical Bayesian estimation and synthetic estimation of the failure probability, as well as synthetic estimation of reliability are given. Calculation and analysis are performed regarding practical problems in case that life distribution of an engine obeys double-parameter exponential distribution. 展开更多
关键词 RELIABILITY zero-failure data failure probability Hierarchical Bayesian estimation Synthetic estimation.
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Bayesian Analysis of Zero-failure Data Based on IFRA Distribution
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作者 张志华 刘海涛 《Defence Technology(防务技术)》 SCIE EI CAS 2009年第1期65-69,共5页
For many products,distributions of their life mostly comply with increasing failure rates in average(IFRA).Aiming to these distributions,using properties of IFRA classification,this paper gives a non-parametric method... For many products,distributions of their life mostly comply with increasing failure rates in average(IFRA).Aiming to these distributions,using properties of IFRA classification,this paper gives a non-parametric method for processing zero-failure data.Estimations of reliabilities in any time are first obtained,and based on a regression model of failure rates,estimations of reliability indexes are given.Finally,a practical example is processed with this method. 展开更多
关键词 无失效数据 香料香精 贝叶斯分析 协会 布基 信度估计 非参数方法 可靠性指标
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Analysis of Incomplete Data of Accelerated Life Testing with Competing Failure Modes 被引量:10
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作者 TAN Yuanyuan ZHANG Chunhua CHEN Xun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第6期883-889,共7页
Data obtained from accelerated life testing (ALT) when there are two or more failure modes, which is commonly referred to as competing failure modes, are often incomplete. The incompleteness is mainly due to censori... Data obtained from accelerated life testing (ALT) when there are two or more failure modes, which is commonly referred to as competing failure modes, are often incomplete. The incompleteness is mainly due to censoring, as well as masking which might be the case that the failure time is observed, but its corresponding failure mode is not identified. Because the identification of the failure mode may be expensive, or very difficult to investigate due to lack of appropriate diagnostics. A method is proposed for analyzing incomplete data of constant stress ALT with competing failure modes. It is assumed that failure modes have s-independent latent lifetimes and the log lifetime of each failure mode can be written as a linear function of stress. The parameters of the model are estimated by using the expectation maximum (EM) algorithm with incomplete data. Simulation studies are performed to check'model validity and investigate the properties of estimates. For further validation, the method is also illustrated by an example, which shows the process of analyze incomplete data from ALT of some insulation system. Because of considering the incompleteness of data in modeling and making use of the EM algorithm in estimating, the method becomes more flexible in ALT analysis. 展开更多
关键词 accelerated life testing competing failure modes expectation maximum algorithm incomplete data Monte Carlo simulation
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BAYESIAN ANALYSIS OF DATA WITH ONLY ONE FAILURE 被引量:4
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作者 Mao Shisong and Chen Jun 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1996年第4期435-444,共10页
The bearings of a certain type have their lives following a Weibull distribution. In a life test with 20 sets of bearings, only one set failed within the specified time, and none of the remainder failed even after th... The bearings of a certain type have their lives following a Weibull distribution. In a life test with 20 sets of bearings, only one set failed within the specified time, and none of the remainder failed even after the time of test has been extended. With a set of testing data like that in Table 1, it is required to estimate the reliability at the mission time. In this paper, we first use hierarchical Bayesian method to determine the prior distribution and the Bayesian estimates of various probabilities of failures, p i 's, then use the method of least squares to estimate the parameters of the Weibull distribution and the reliability. Actual computation shows that the estimates so obtained are rather robust. And the results have been adopted for practical use. 展开更多
关键词 ONLY ONE WITH data failure OF ANALYSIS BAYESIAN
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Enhancing Interest Forwarding for Fast Recovery from Unanticipated Data Access Failure in NDN 被引量:1
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作者 Xiaoyan Hu Xuhui Liu +2 位作者 Lixia Zhao Jian Gong Guang Cheng 《China Communications》 SCIE CSCD 2019年第7期120-130,共11页
We show that an aggregated Interest in Named Data Networking (NDN) may fail to retrieve desired data since the Interest previously sent upstream for the same content is judged as a duplicate one and then dropped by an... We show that an aggregated Interest in Named Data Networking (NDN) may fail to retrieve desired data since the Interest previously sent upstream for the same content is judged as a duplicate one and then dropped by an upstream node due to its multipath forwarding. Furthermore, we propose NDRUDAF, a NACK based mechanism that enhances the Interest forwarding and enables Detection and fast Recovery from such Unanticipated Data Access Failure. In the NDN enhanced with NDRUDAF, the router that aggregates the Interest detects such unanticipated data access failure based on a negative acknowledgement from the upstream node that judges the Interest as a duplicate one. Then the router retransmits the Interest as soon as possible on behalf of the requester whose Interest is aggregated to fast recover from the data access failure. We qualitatively and quantitatively analyze the performance of the NDN enhanced with our proposed NDRUDAF and compare it with that of the present NDN. Our experimental results validate that NDRUDAF improves the system performance in case of such unanticipated data access failure in terms of data access delay and network resource utilization efficiency at routers. 展开更多
关键词 named data networking INTEREST aggregation multipath FORWARDING data access failure negative ACKNOWLEDGEMENT
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FP-STE: A Novel Node Failure Prediction Method Based on Spatio-Temporal Feature Extraction in Data Centers 被引量:2
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作者 Yang Yang Jing Dong +2 位作者 Chao Fang Ping Xie Na An 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第6期1015-1031,共17页
The development of cloud computing and virtualization technology has brought great challenges to the reliability of data center services.Data centers typically contain a large number of compute and storage nodes which... The development of cloud computing and virtualization technology has brought great challenges to the reliability of data center services.Data centers typically contain a large number of compute and storage nodes which may fail and affect the quality of service.Failure prediction is an important means of ensuring service availability.Predicting node failure in cloud-based data centers is challenging because the failure symptoms reflected have complex characteristics,and the distribution imbalance between the failure sample and the normal sample is widespread,resulting in inaccurate failure prediction.Targeting these challenges,this paper proposes a novel failure prediction method FP-STE(Failure Prediction based on Spatio-temporal Feature Extraction).Firstly,an improved recurrent neural network HW-GRU(Improved GRU based on HighWay network)and a convolutional neural network CNN are used to extract the temporal features and spatial features of multivariate data respectively to increase the discrimination of different types of failure symptoms which improves the accuracy of prediction.Then the intermediate results of the two models are added as features into SCSXGBoost to predict the possibility and the precise type of node failure in the future.SCS-XGBoost is an ensemble learning model that is improved by the integrated strategy of oversampling and cost-sensitive learning.Experimental results based on real data sets confirm the effectiveness and superiority of FP-STE. 展开更多
关键词 failure prediction data center features extraction XGBoost service availability
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Machine Learning and Artificial Neural Network for Predicting Heart Failure Risk
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作者 Polin Rahman Ahmed Rifat +3 位作者 MD.IftehadAmjad Chy Mohammad Monirujjaman Khan Mehedi Masud Sultan Aljahdali 《Computer Systems Science & Engineering》 SCIE EI 2023年第1期757-775,共19页
Heart failure is now widely spread throughout the world.Heart disease affects approximately 48%of the population.It is too expensive and also difficult to cure the disease.This research paper represents machine learni... Heart failure is now widely spread throughout the world.Heart disease affects approximately 48%of the population.It is too expensive and also difficult to cure the disease.This research paper represents machine learning models to predict heart failure.The fundamental concept is to compare the correctness of various Machine Learning(ML)algorithms and boost algorithms to improve models’accuracy for prediction.Some supervised algorithms like K-Nearest Neighbor(KNN),Support Vector Machine(SVM),Decision Trees(DT),Random Forest(RF),Logistic Regression(LR)are considered to achieve the best results.Some boosting algorithms like Extreme Gradient Boosting(XGBoost)and Cat-Boost are also used to improve the prediction using Artificial Neural Networks(ANN).This research also focuses on data visualization to identify patterns,trends,and outliers in a massive data set.Python and Scikit-learns are used for ML.Tensor Flow and Keras,along with Python,are used for ANN model train-ing.The DT and RF algorithms achieved the highest accuracy of 95%among the classifiers.Meanwhile,KNN obtained a second height accuracy of 93.33%.XGBoost had a gratified accuracy of 91.67%,SVM,CATBoost,and ANN had an accuracy of 90%,and LR had 88.33%accuracy. 展开更多
关键词 Heart failure prediction data visualization machine learning k-nearest neighbors support vector machine decision tree random forest logistic regression xgboost and catboost artificial neural network
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Reliability evaluation of bladder accumulator with no failure data 被引量:1
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作者 郭锐 Zhang Rongbing +2 位作者 Zhao Jingyi Zhou Jinsheng Zhang Zhenmiao 《High Technology Letters》 EI CAS 2018年第3期322-329,共8页
As a bladder accumulator is a high reliable and long life component in a hydraulic system,its cost is high and it takes a lot of time to test its reliability,therefore,a reliability test with small sample is performed... As a bladder accumulator is a high reliable and long life component in a hydraulic system,its cost is high and it takes a lot of time to test its reliability,therefore,a reliability test with small sample is performed,and no failure data is obtained using the method of fixed time truncation. In the case of Weibull distribution,a life reliability model of bladder energy storage is established by Bayesian method using the optimal confidence intervals method,a model of one-sided lower confidence intervals of the reliability and one-sided lower confidence intervals model of the reliability life are established. Results of experiments show that the evaluation method of no failure data under Weibull distribution is a good way to evaluate the reliability of the accumulator,which is convenient for engineering application,and the reliability of the accumulator has theoretical and practical significance. 展开更多
关键词 bladder accumulator Weibull distribution fixed time truncation no failure data reliability assessment
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Bayesian and Non-Bayesian Analysis for the Sine Generalized Linear Exponential Model under Progressively Censored Data
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作者 Naif Alotaibi A.S.Al-Moisheer +2 位作者 Ibrahim Elbatal Mohammed Elgarhy Ehab M.Almetwally 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第9期2795-2823,共29页
This article introduces a novel variant of the generalized linear exponential(GLE)distribution,known as the sine generalized linear exponential(SGLE)distribution.The SGLE distribution utilizes the sine transformation ... This article introduces a novel variant of the generalized linear exponential(GLE)distribution,known as the sine generalized linear exponential(SGLE)distribution.The SGLE distribution utilizes the sine transformation to enhance its capabilities.The updated distribution is very adaptable and may be efficiently used in the modeling of survival data and dependability issues.The suggested model incorporates a hazard rate function(HRF)that may display a rising,J-shaped,or bathtub form,depending on its unique characteristics.This model includes many well-known lifespan distributions as separate sub-models.The suggested model is accompanied with a range of statistical features.The model parameters are examined using the techniques of maximum likelihood and Bayesian estimation using progressively censored data.In order to evaluate the effectiveness of these techniques,we provide a set of simulated data for testing purposes.The relevance of the newly presented model is shown via two real-world dataset applications,highlighting its superiority over other respected similar models. 展开更多
关键词 Sine G family generalized linear failure rate progressively censored data MOMENTS maximum likelihood estimation Bayesian estimation simulation
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An interpretability model for syndrome differentiation of HBV-ACLF in traditional Chinese medicine using small-sample imbalanced data
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作者 ZHOU Zhan PENG Qinghua +3 位作者 XIAO Xiaoxia ZOU Beiji LIU Bin GUO Shuixia 《Digital Chinese Medicine》 CAS CSCD 2024年第2期137-147,共11页
Objective Clinical medical record data associated with hepatitis B-related acute-on-chronic liver failure(HBV-ACLF)generally have small sample sizes and a class imbalance.However,most machine learning models are desig... Objective Clinical medical record data associated with hepatitis B-related acute-on-chronic liver failure(HBV-ACLF)generally have small sample sizes and a class imbalance.However,most machine learning models are designed based on balanced data and lack interpretability.This study aimed to propose a traditional Chinese medicine(TCM)diagnostic model for HBV-ACLF based on the TCM syndrome differentiation and treatment theory,which is clinically interpretable and highly accurate.Methods We collected medical records from 261 patients diagnosed with HBV-ACLF,including three syndromes:Yang jaundice(214 cases),Yang-Yin jaundice(41 cases),and Yin jaundice(6 cases).To avoid overfitting of the machine learning model,we excluded the cases of Yin jaundice.After data standardization and cleaning,we obtained 255 relevant medical records of Yang jaundice and Yang-Yin jaundice.To address the class imbalance issue,we employed the oversampling method and five machine learning methods,including logistic regression(LR),support vector machine(SVM),decision tree(DT),random forest(RF),and extreme gradient boosting(XGBoost)to construct the syndrome diagnosis models.This study used precision,F1 score,the area under the receiver operating characteristic(ROC)curve(AUC),and accuracy as model evaluation metrics.The model with the best classification performance was selected to extract the diagnostic rule,and its clinical significance was thoroughly analyzed.Furthermore,we proposed a novel multiple-round stable rule extraction(MRSRE)method to obtain a stable rule set of features that can exhibit the model’s clinical interpretability.Results The precision of the five machine learning models built using oversampled balanced data exceeded 0.90.Among these models,the accuracy of RF classification of syndrome types was 0.92,and the mean F1 scores of the two categories of Yang jaundice and Yang-Yin jaundice were 0.93 and 0.94,respectively.Additionally,the AUC was 0.98.The extraction rules of the RF syndrome differentiation model based on the MRSRE method revealed that the common features of Yang jaundice and Yang-Yin jaundice were wiry pulse,yellowing of the urine,skin,and eyes,normal tongue body,healthy sublingual vessel,nausea,oil loathing,and poor appetite.The main features of Yang jaundice were a red tongue body and thickened sublingual vessels,whereas those of Yang-Yin jaundice were a dark tongue body,pale white tongue body,white tongue coating,lack of strength,slippery pulse,light red tongue body,slimy tongue coating,and abdominal distension.This is aligned with the classifications made by TCM experts based on TCM syndrome differentiation and treatment theory.Conclusion Our model can be utilized for differentiating HBV-ACLF syndromes,which has the potential to be applied to generate other clinically interpretable models with high accuracy on clinical data characterized by small sample sizes and a class imbalance. 展开更多
关键词 Traditional Chinese medicine(TCM) Hepatitis B-related acute-on-chronic liver failure(HBV-ACLF) Imbalanced data Random forest(RF) INTERPRETABILITY
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Sampled-data synchronization of coupled harmonic oscillators with controller failure and communication delays 被引量:1
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作者 Jin Zhou Hua Zhang +1 位作者 Lan Xiang Quanjun Wu 《Theoretical & Applied Mechanics Letters》 CAS 2013年第6期15-19,共5页
In this letter, a distributed protocol for sampled-data synchronization of coupled harmonic oscillators with controller failure and communication delays is proposed, and a brief procedure of convergence analysis for s... In this letter, a distributed protocol for sampled-data synchronization of coupled harmonic oscillators with controller failure and communication delays is proposed, and a brief procedure of convergence analysis for such algorithm over undirected connected graphs is provided. Furthermore, a simple yet generic criterion is also presented to guarantee synchronized oscillatory motions in coupled harmonic oscillators. Subsequently, the simulation results are worked out to demonstrate the efficiency and feasibility of the theoretical results. 展开更多
关键词 sampled-data synchronization coupled harmonic oscillators controller failure communi-cation delays
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Inverse Estimation on Trigger Factors of Simultaneous Slope Failures with Purification of Training Data Sets
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作者 Hirohito Kojima Ryo Sekine +1 位作者 Tomoya Yoshida Ryo Nozaki 《Journal of Earth Science and Engineering》 2013年第9期594-602,共9页
This paper presents an procedure for purifying training data sets (i.e., past occurrences of slope failures) for inverse estimation on unobserved trigger factors of "different types of simultaneous slope failures"... This paper presents an procedure for purifying training data sets (i.e., past occurrences of slope failures) for inverse estimation on unobserved trigger factors of "different types of simultaneous slope failures". Due to difficulties in pixel-by-pixel observations of trigger factors, as one of the measures, the authors had proposed an inverse analysis algorithm on trigger factors based on SEM (structural equation modeling). Through a measurement equation, the trigger factor is inversely estimated, and a TFI (trigger factor influence) map can be also produced. As a subsequence subject, a purification procedure of training data set should be constructed to improve the accuracy of TFI map which depends on the representativeness of given training data sets of different types of slope failures. The proposed procedure resamples the matched pixels between original groups of past slope failures (i.e., surface slope failures, deep-seated slope failures, landslides) and classified three groups by K-means clustering for all pixels corresponding to those slope failures. For all cases of three types of slope failures, the improvement of success rates with respect to resampled training data sets was confirmed. As a final outcome, the differences between TFI maps produced by using original and resampled training data sets, respectively, are delineated on a DIF map (difference map) which is useful for analyzing trigger factor influence in terms of "risky- and safe-side assessment" sub-areas with respect to "different types of simultaneous slope failures". 展开更多
关键词 Purification of training data simultaneous slope failures inverse analysis of unobserved trigger factor spatial data integration structural equation modeling.
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Calibration of Four Nonlinear Failure Envelopes from Triaxial Test Data and Influence of Nonlinearity on Geotechnical Computations
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作者 Amaechi J. Anyaegbunam Fidelis O. Okafor 《Geomaterials》 2021年第2期42-57,共16页
It is now recognized that many geomaterials have nonlinear failure envelopes. This non-linearity is most marked at lower stress levels, the failure envelope being of quasi-parabolic shape. It is not easy to calibrate ... It is now recognized that many geomaterials have nonlinear failure envelopes. This non-linearity is most marked at lower stress levels, the failure envelope being of quasi-parabolic shape. It is not easy to calibrate these nonlinear failure envelopes from triaxial test data. Currently only the power-type failure envelope has been studied with an established formal procedure for its determination from triaxial test data. In this paper, a simplified procedure is evolved for the development of four different types of nonlinear envelopes. These are of invaluable assistance in the evaluation of true factors of safety in problems of slope stability and correct computation of lateral earth pressure and bearing capacity. The use of the Mohr-Coulomb failure envelopes leads to an overestimation of the factors of safety and other geotechnical quantities. 展开更多
关键词 Calibration of Nonlinear failure Envelope Triaxial Test data Modified Maksimovic Envelope Power-Type Envelope Polynomial-Type Envelope Hoek-Brown Envelope Standard Error of Estimate
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Failure Mode and Effects Analysis (FMEA) by Fuzzy Data Envelop Analysis (Fuzzy-DEA)
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作者 Hamed Rahmani Milad Jasemi 《Journal of Mathematics and System Science》 2014年第3期173-179,共7页
Failure mode and effects analysis (FMEA) offers a quick and easy way for identifying ranking-order for all failure modes in a system or a product. In FMEA the ranking methods is so called risk priority number (RPN... Failure mode and effects analysis (FMEA) offers a quick and easy way for identifying ranking-order for all failure modes in a system or a product. In FMEA the ranking methods is so called risk priority number (RPN), which is a mathematical product of severity (S), occurrence (0), and detection (D). One of major disadvantages of this ranking-order is that the failure mode with different combination of SODs may generate same RPN resulting in difficult decision-making. Another shortfall of FMEA is lacking of discerning contribution factors, which lead to insufficient information about scaling of improving effort. Through data envelopment analysis (DEA) technique and its extension, the proposed approach evolves the current rankings for failure modes by exclusively investigating SOD in lieu of RPN and to furnish with improving sca.les for SOD. The purpose of present study is to propose a state-of-the-art new approach to enhance assessment capabilities of failure mode and effects analysis (FMEA). The paper proposes a state-of-the-art new approach, robust, structured and useful in practice, for failure analysis. 展开更多
关键词 failure mode and effects analysis (FMEA) data envelopment analysis (DEA) risk priority number (RPN).
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System reliability assessment based on Wiener process and competing failure analysis 被引量:3
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作者 苏春 张烨 《Journal of Southeast University(English Edition)》 EI CAS 2010年第4期554-557,共4页
Considering the dependence and competitive relation-ship between traumatic failure and degradation,the reliability assessment of products based on competing failure analysis is studied.The hazard rate of traumatic fai... Considering the dependence and competitive relation-ship between traumatic failure and degradation,the reliability assessment of products based on competing failure analysis is studied.The hazard rate of traumatic failure is regarded as a Weibull distribution of the degradation performance,and the Wiener process is used to describe the degradation process.The parameters are estimated with the maximum likelihood estimation(MLE)method.A reliability model based on competing failure analysis is proposed.A case study of the GaAs lasers is given to validate the effectiveness of the model and its solving method.The results indicate that if only the degradation failure is considered,the estimated result will be comparably optimistic.Meanwhile,the correlation between the degradation and traumatic failure has a great influence on the accuracy of reliability assessment. 展开更多
关键词 degradation data Wiener process competing failure reliability assessment
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