A Multi-mode Incipient Sensor Fault Detection and Diagnosis Method for Electrical Traction Systems

Hongtian Chen,Bin Jiang,Ningyun Lu 제어·로봇·시스템학회 2018 International Journal of Control, Automation, and Vol.16 No.4

This paper proposes a data-driven sensor fault detection and diagnosis (FDD) method for electrical traction systems. Considering their switched characteristics, electrical traction systems can be regarded as switched systems. A mixture non-Gaussian data set will be formed, which can be firstly divided into six different operation modes, and principal component analysis (PCA) is then used for feature extraction in each mode. For two fault indicators in principal and residual subspaces, their probability density functions (PDFs) are estimated and used to determine reasonable thresholds for FDD. The proposed methodology extends the application of multivariate statistical technology to electrical traction systems. It can be applied easily and effectively without requirements on system parameters, and can deal with incipient sensor faults in traction system. Experiments with several different types of incipient sensor faults are conducted, which can demonstrate the effectiveness of the proposed method.

Expression and Regulation of Transcription Factor FoxA2 in Chronic Rhinosinusitis With and Without Nasal Polyps

Qing Luo,Jia Zhang,Hongtian Wang,Fenghong Chen,Xi Luo,Beiping Miao,Xingmei Wu,Renqiang Ma,Xiangqian Luo,Geng Xu,Jianbo Shi,Huabin Li 대한천식알레르기학회 2015 Allergy, Asthma & Immunology Research Vol.7 No.5

Purpose: Chronic rhinosinusitis (CRS) is characterized by the excessive production of mucus. However, the molecular mechanism underlying mucin overproduction in CRS with or without nasal polyps (CRSwNP and CRSsNP, respectively) is poorly understood. This study was conducted to assess the importance of the transcription factor FoxA2 in mucin production and to investigate the targeting of FoxA2 as a potential therapeutic strategy for mucus hypersecretion in CRS patients. Methods: We enrolled 15 CRSwNP patients, 15 CRSsNP patients, and 10 normal controls in this study. The expression levels of FoxA2, MUC5AC, and MUC5B in inflamed and healthy nasal tissues were examined via immunohistochemistry and quantitative reverse transcription-polymerase chain reaction, and the levels of several proinflammatory cytokines in nasal secretions were measured via FlowCytomix analysis. In addition, the expression of MUC5AC and FoxA2 was determined in polyp-derived epithelial cells and NCI-H292 cells after in vitro stimulation. Results: FoxA2 was significantly down-regulated, and MUC5AC and MUC5B were significantly up-regulated in both the CRSwNP and CRSsNP patients compared to the controls (P<0.05), and the protein level of FoxA2 was negatively associated with the IL-6 level in the CRS patients (P<0.05). IL-6 significantly increased MUC5AC expression but inhibited FoxA2 expression in vitro (P<0.05). Transfection with a FoxA2 expression plasmid significantly decreased MUC5AC promoter activity (P<0.05) and inhibited IL-6-induced MUC5AC production (P<0.05). In addition, clarithromycin significantly alleviated IL-6-induced FoxA2 suppression and decreased MUC5AC expression in vitro (P<0.05). Conclusions: Our findings suggest that FoxA2 may be considered a therapeutic target for the modulation of mucus hypersecretion in CRS patients.

Determination Method for the Strength Model of a Jointed Rock Mass Based on the Geological Strength Index

Shijie Sun,Maolin Tian,Hongtian Xiao,Ying Wang 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.7

The mechanical characteristics of materials are the key to numerical calculation, thedetermination of material parameters of jointed rock mass is conundrum in academia. For thepurpose of more efficiently and accurately select the mechanical parameters of the jointedrock masses, in this paper, a new method is proposed which for constructing a numericalmodel of jointed rock masses, which based on the Geological Strength Index (GSI) and theprinciples of damage mechanics. With the help of basic concepts of damage mechanics, thejoint equivalent coefficient is proposed, establishing the relationship between GSI and jointspacing. The selection way for the mechanical parameters of a jointed rock masses is given incombination with the Hoek-Brown strength criterion. Then, a numerical calculation model isconstructed by utilizing 3DEC numerical simulation software to discuss the stability of theadjoining rock under the condition of different GSIs, which is successfully applied to theWangjialing coal mine project. The numerical results match quite closely with the fieldconditions, the maximum error is 18%, the minimum error is 5.6%, verifying the rationalityand accuracy of this way and providing a new way for the accurate numerical simulation ofjointed rock masses.

Just-in-time Learning-aided Nonlinear Fault Detection for Traction Systems of High-speed Trains

Chao Cheng,Xiuyuan Sun,Junjie Shao,Hongtian Chen,Chao Shang 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.9

Traction systems in high-speed trains exhibit significant dynamic characteristics, which mainly arise from operation-point changes. Most existing fault detection methods provide static data models for global structures, especially for traditional multivariate statistical analysis methods constrained by constant operating points. The symptoms of incipient faults are slight and easily hidden. Despite the moderate effect of incipient faults, they will compromise the overall performance and remaining life of traction systems in the long run. Therefore, a just-in-time slow feature analysis method is proposed in this study. The salient advantages of the proposed method are: 1) It can be applied to dynamic non-linear systems; 2) It can detect incipient faults subject to environments containing noise and unknown disturbances; 3) It mitigates false alarms caused by parameter mutation during mode-switching. A series of experiments are carried out on a traction system platform to verify the effectiveness and superiority of the proposed method.

Diets structure of a common lizard Eremias argus and their effects on grasshoppers: Implications for a potential biological agent

Xunbing Huang,Huihui Wu,Xiongbing Tu,Zhuoran Zhang,Hongtian Su,Yongming Shi,Guang-Jun Wang,Guangchun Cao,Xiangqun Nong,Zehua Zhang 한국응용곤충학회 2016 Journal of Asia-Pacific Entomology Vol.19 No.1

Outbreaks of grasshoppers (Orthoptera: Acrididae) often cause serious ecological damage. Recently, there has been interest in using natural enemies of grasshopper for their biological control. This study examined the biology and predation on grasshoppers by Eremias argus, a common lizard in Inner Mongolia. Its developmental duration and life history are consistent with adaptation to grasshopper phenology. The diet structure of E. argus included grasshoppers, beetles, ants, leafhoppers, moths, bees and spiders. A positive correlation between E. argus population numbers and grasshopper population numbers was highly significant. We built models describing the functional response and intraspecific competition for E. argus adults. The functional feeding response of E. argus on grasshopper was classed as Holling type III. The maximum number of grasshoppers consumed by female and male adults were 11.2 and 7.0 individuals per day, respectively. Predatory ability was strongest in female adults, with the second and third instars of Oedaleus asiaticus preferred. The predation ratios(E) of E. argus on grasshoppers declinedwith increasing lizard density, especially for female adult E. argus. E. argus could play an important role in grasshopper control and maintaining a population of E. argus in the grassland ecosystemcould effectively control low-density grasshopper populations on grassland. Suggestions on how E. argus could fit into an IPM programme for biological control of grasshopper are discussed.

Gene microarray analysis revealed a potential crucial gene RACK1 in oral squamous cell carcinoma (OSCC)

Jian-Wei Zheng,Yinshen Yang,Shujuan Yang,Wei Zhou,Hongtian Qiu,Xiaoping Li,Qiuyun Cai,Ting Li,Gang Luo 한국통합생물학회 2018 Animal cells and systems Vol.22 No.2

Oral squamous cell carcinoma (OSCC) is the sixth most common cancer worldwide, which appears as a consequence of multiple molecular genetic events in various chromosomes and genes. In order to unveil the possible mechanisms underlying OSCC tumorigenesis, the OSCC-related gene expression variance and the gene interaction network should be further investigated. Herein, we conducted the NimbleGen Human Gene Expression Microarray to analyze expression heterogeneity between OSCC primary tumor tissue and its adjacent normal tissue from two patients. A total number of 7872 out of 32,448 detected genes are differentially expressed in OSCC. Gene ontology (GO) analysis demonstrated that these differentially expressed transcripts were critical in a series of metabolic processes, cancer-related signal pathways, and biological regulations. KEGG signaling pathway enrichment suggested a number of pathways (metabolic process and immune response) which are frequently enrolled during cancer progression. 15 most differential regulated genes between OSCC tumor and non-tumor were confirmed by quantitative reverse transcription polymerase chain reaction (qRT-PCR). Furthermore, the interaction network analysis of these confirmed genes by STRING database showed the two subunits of RACK1 had direct interaction with 14 differential proteins. This bioinformatics research lends support about the critical role of RACK1 which functions as a key node protein driving OSCC development.