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Study of Feature Extraction Based on Autoregressive Modeling in ECG Automatic Diagnosis

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自动化学报 2007年第5期33卷 462-466页

作者： GE Ding-Fei hou Bei-ping XIANG Xin-Jian School of Information and Electronic Engineering Zhejiang University of Science and Technology Hangzhou 310012 P. R. China

This article explores the ability of multivariate autoregressive model(MAR)and scalar AR model to extract the features from two-lead electrocardiogram signals in order to classify certain cardiac *** classification performance of four different ECG feature sets based on the model coefficients are *** data in the analysis including normal sinus rhythm, atria premature contraction,premature ventricular contraction,ventricular tachycardia,ventricular fibrillation and superventricular tachyeardia is obtained from the MIT-BIH *** classification is performed using a quadratic diacriminant *** results show the MAR coefficients produce the best results among the four ECG representations and the MAR modeling is a useful classification and diagnosis tool.

关键词：自动诊断多元自回归模型特征提取心电图

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磁场下碳化物析出的热力学机制

原子与分子物理学报 2025年第4期42卷 121-130页

作者：廖已莹侯廷平杨雨豪郑一航于涛刘伍明吴开明武汉科技大学理学院武汉430081 冶金工业过程系统科学湖北省重点实验室武汉430081 省部共建耐火材料与冶金国家重点实验室武汉430081 江汉大学光电材料与技术学院光电化学材料与器件教育部重点实验室武汉430056 中国科学院物理研究所北京100190

钢中碳化物的形成主要由合金元素的种类以及含量的决定,碳化物对钢铁材料的显微组织形态和力学性能有重要影响.磁场是影响碳化物析出规律发生改变的重要因素之一.以常见的碳化物M_(6)C(M=Fe,Mo)作为研究对象,利用第一性原理计算η-Fe_(... 详细信息

钢中碳化物的形成主要由合金元素的种类以及含量的决定,碳化物对钢铁材料的显微组织形态和力学性能有重要影响.磁场是影响碳化物析出规律发生改变的重要因素之一.以常见的碳化物M_(6)C(M=Fe,Mo)作为研究对象,利用第一性原理计算η-Fe_(2)C、Fe_(3)C、Fe_(2)Mo_(4)C、Fe_(3)Mo_(3)C-Ⅰ、Fe_(3)Mo_(3)C-Ⅱ和Fe_(4)Mo_(2)C等合金碳化物的磁矩,计算结果表明其中Fe_(4)Mo_(2)C的磁矩最大,达到了7.04μB.磁矩不仅由碳化物晶胞中Fe原子个数有关,还与Fe Wyckoff占位紧密相关.通过模拟计算碳化物的磁致磁热熔、磁熵、磁焓和磁自由能,从热力学角度对各碳化物进行分析,结果表明磁场会使碳化物的磁致磁热熔和磁熵增加;强磁场会降低M_(6)C的磁自由能进而提高其稳定性.此工作为研究核聚变材料磁性能提供理论基础和技术参考.

关键词：磁场碳化物析出相热力学机制

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Epidemiology and outcome of individuals with intraductal papillary neoplasms of the bile duct

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World Journal of Gastrointestinal Oncology 2023年第5期15卷 843-858页

作者： Rong-Shou Wu Wen-Jun Liao Jing-Sheng Ma Jia-Kun Wang Lin-Quan Wu ping hou Department of Hepatobiliary and Pancreatic Surgery The Second Affiliated Hospital of Nanchang UniversityNanchang 330000Jiangxi ProvinceChina Department of Organ Transplantation The Second Affiliated Hospital of Nanchang UniversityNanchang 330000Jiangxi ProvinceChina Department of General Surgery The First Affiliated Hospital of Gannan Medical CollegeNo.23 Qingnian RoadZhanggong DistrictGanzhou 341000Jiangxi ProvinceChina

BACKGROUND Intraductal papillary neoplasm of the bile duct(IPNB)is a rare distinct subtype of precursor lesions of biliary *** is considered to originate from luminal biliary epithelial cells,typically displays mucin-hypersecretion or a papillary growth pattern,and results in cystic dilatation[1].IPNB develops anywhere in the intrahepatic and extrahepatic biliary tracts,and can occur in various pathological stages from low-grade dysplasia to invasive *** have similar phenotypic changes in the occurrence and development of all subtypes,and the prognosis is significantly better than that of traditional(nonpapillary)*** To evaluate the clinicopathological features of IPNB to provide evidence-based guidance for *** Invasive IPNB,invasive intraductal papillary mucinous neoplasm of the pancreas(IPMN),and traditional cholangiocarcinoma data for affected individuals from 1975 to 2016 were obtained from the Surveillance,Epidemiology,and End Results(SEER)*** percentage changes(APCs)in the incidence and incidence-based(IB)mortality were *** identified the independent predictors of overall survival(OS)and cancer-specific survival(CSS)in indivi duals with invasive *** The incidence and IB mortality of invasive IPNB showed sustained decreases,with an APC of-4.5%(95%CI:-5.1%to-3.8%)and-3.3%(95%CI:-4.1%to-2.6%)(P<0.001),*** decreases in incidence and IB mortality were seen for invasive IPMN but not for traditional *** OS and CSS for invasive IPNB were better than for invasive IPMN and traditional cholangiocarcinoma.A total of 1635 individuals with invasive IPNB were included in our prognosis *** most common tumor sites were the pancreaticobiliary ampulla(47.9%)and perihilar tract(36.7%),but the mucin-related subtype of invasive IPNB was the main type,intrahepatically(approximately 90%).In the univariate and multivariate Cox regression analysis,age,tum

关键词： Surveillance,Epidemiology,and End Results database Intraductal papillary neoplasms of the bile duct Subtype Annual percentage changes Prognosis

Coordinate control of initiative mating device for autonomous underwater vehicle based on TDES

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Journal of Marine Science and Application 2005年第2期4卷 20-27页

作者： YAN Zhe-ping hou Shu-ping School of Power and Nuclear Energy Engineering Harbin Engineering University Harbin 150001 China School of Mechanical and Electrical Engineering Harbin Engineering University Harbin 150001 China

A novel initiative mating device, which has four 2-degree manipulators around the mating skirt, is proposed to mate between a skirt of AUV （autonomons underwater vehicle） and a disabled submarine. The primary function of the device is to keep exact mating between skirt and disabled submarine in a badly sub sea environment. According to the characteristic of rescue, an automaton model is brought forward to describe the mating proceed between AUV and manipulators. The coordinated control is implemented by the TDES （time discrete event system）. After taking into account the time problem, it is a useful method to control mating by sinmlation testing. The result shows that it reduces about 70 seconds after using intelligent co-ordinate control based on TDES through the whole mating procedure.

关键词： AUV initiative mating coordinated control TDES

Important role of schemata in language communication： Based on a real case

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Sino-US English Teaching 2007年第6期4卷 57-60页

作者： hou Jun-ping College of Foreign Languages Shaanxi Normal University Xi＇an 710062 China

When we communicate with others, we are about to encounter certain types of discourse, and transfer some new information. If we want to be understood correctly, we should try to connect with the schemata which exist in the participants, arousing their experienced knowledge of what we mentioned in our expression. The real sample in the thesis is a strong support to this opinion.

关键词： communication language schemata

Study on the Microstructure and Dielectric Properties of Barium Strontium Titanate Thin Films Prepared by Sol-gel Method

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Chinese Journal of Aeronautics 2006年第B12期19卷 167-172页

作者： SHAN Lian-wei ZHANG Xian-you DONG Li-min WU Ze HAN Zhi-dong FU Xing-hua hou Wen-ping Department of Materials Science and Engineering Harbin University of Science and Technology Harbin 150040 China Department of Materials Science and Engineering Jinan University Jinan 250022 China

Sr05Ba0.5-xBixTiO3 （BST） thin films were fabricated on a Pt/SiO2/Si substrate by the sol-gel method. Then follows an investigation of the influeoces of bismuth （Bi） on the microstructures and the dielectric properties of Sr0.5Ba0.5-xBixTiO3 （BST） thin films. The microstructures of the BST thin films were examined by the XRD and the TEM techniques. Tetragonal perovskite crystal grains were observed in BST thin films. Increasing Bi^3＋ doping ration in BST will lead to decrease of the grain size. It is found that Bi^3＋ doping decreases the dielectric loss and improves the frequency dispersion of the BST thin films. Not only is compressed the peak of temperature-dependence of dielectric constant of Bi^3＋-doped BST thin films but also moves into the low-temperature region. Moreover, the average Curie tem- perature decreases gradually with the Bi^3＋ contents increasing.

关键词： BST thin films Bi doping characteristic microstructure

Screening and Identifying Hepatotoxic Components in Polygoni multiflori Radix and Polygoni multiflori Radix Praeparata

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World Journal of Traditional Chinese Medicine 2019年第3期5卷 173-179页

作者： Guang-ping Zhang Hai-Jing Zhang Teng-Fei Chen Hong-ping hou ping Su Yun-Hang Gao Yi-Fei Yang Zu-Guang Ye Atomized Inhalation Preparation Research Center Institute of Chinese Materia Medica China Academy of Chinese Medical Sciences

Objective: In this study, the hepatotoxic components of Polygoni multiflori Radix and Polygoni multiflori Radix Praeparata(known as Heshouwu [HSW] and Zhiheshouwu [ZHSW] in China, respectively) were screened, isolated, and identified. Materials and Methods: The ethanol extracts of HSW and ZHSW were separated into 80 fractions according to their polarity in the preparation liquid phase. Chang liver cell line was used to screen the toxic components of HSW and ZHSW in vitro. The obtained toxic mixture was further collected, isolated, and identified to confirm the hepatotoxic compounds of HSW and ZHSW. Results: The identifid hepatotoxic compounds include 2,3,5,4’-tetrah ydroxystilbene-2-O-β-D-glucoside, emodin, physcion-8-O-β-d-glucoside, physcion, and citreorosein, the fist two among them were the main components of HSW and ZHSW. After processing of HSW, the contents of 2,3,5,4’-tetrahydroxystilbene-2-O-β-D-glucoside and emodin in ZHSW were signifiantly decreased. Conclusions: The traditional processing with herb has signifiant effects on the components, especially the toxic components, in the extract of HSW and is an effective method to reduce its toxicity.

关键词： 2,3,5,4’-tetra-hydroxystilbene-2-O-β-D-glucoside emodin hepatotoxicity Polygoni multiflori Radix Polygoni multiflori Radix Praeparata

Low-dose spectral insufflation computed tomography protocol preoperatively optimized for T stage esophageal cancer-preliminary research experience

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World Journal of Gastroenterology 2018年第36期24卷 4197-4207页

作者： Yue Zhou Dan Liu ping hou Kai-Ji Zha Feng Wang Kun Zhou Wei He Jian-Bo Gao Department of Radiology The First Affiliated Hospital of Zhengzhou University Department of Gastroenterology The First Affiliated Hospital of Zhengzhou University Department of Oncology The First Affiliated Hospital of Zhengzhou University Department of Thoracic Surgery The First Affiliated Hospital of Zhengzhou University

AIM To evaluate the T stage of esophageal squamous cell carcinoma(ESCC) using preoperative low-dose esophageal insufflation computed tomography(EICT).METHODS One hundred and twenty ESCC patients confirmed by surgery or esophagoscopy were divided into three groups. Groups B and C were injected with 300 mgI/kg contrast medium for automatic spectral imaging assist(GSI assist), while group A underwent a conventional 120 kVp computed tomography(CT) scan with a 450 mg I/kg contrast medium injection. EICT was performed in group C. Group A was reconstructed with filtered back projection, and groups B and C were reconstructed with 50% adaptive statistical iterative reconstruction. The contrast-to-noise ratio of lesion-to-mediastinal adipose tissue and the radiation dose were measured. Specific imaging features were observed, and T stage ESCCs were *** The sensitivity and accuracy of the T1/2 stage were higher in group C than in groups A and B(sensitivity: 43.75% vs 31.82% and 33.33%; accuracy: 54.29% vs 46.67% and 52.50%, respectively). With regard to the T3 stage, the sensitivity and specificity in group C were higher than those in groups A and B(sensitivity: 56.25% vs 41.17% and 44.44%; specificity: 73.68% vs 67.86% and 63.64%, respectively). The diagnostic sensitivity, specificity and accuracy of the T4 stage were similar among all groups. There were no significant differences in volume CT dose index [(5.91 ± 2.57) mGy vs(3.24 ± 1.20) vs(3.65 ± 1.77) mGy], doselength product [(167.10 ± 99.08) mGy·cm vs(113.24 ± 54.46) mGy·cm vs(117.98 ± 32.32) mGy·cm] and effective dose [(2.52 ± 1.39) vs(1.63 ± 0.76) vs(1.73 ± 0.44) mSv] among the groups(P > 0.05). However, groups B and C received similar effective doses but lower iodine loads than group A [(300 vs 450) mgI/kg].CONCLUSION EICT combined with GSI assist allows differential diagnosis between the T1/2 and T3 stages. The ability to differentially diagnose the T3 and T4 stages of medullary ESCC can be improved by

关键词： Esophageal neoplasms tomography tumor staging

Synthesis and biological evaluation of novel pyrazole carboxamide with diarylamine-modified scaffold as potent antifungal agents

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Chinese Chemical Letters 2017年第8期28卷 1731-1736页

作者： Xiao-Xiao Zhang Hong Jin Yuan-Jie Deng Xu-Heng Gao Yong Li Yong-Tian Zhao Ke Tao Tai-ping hou Key Laboratory of Bio-Resource and Eco-environment of Ministry of Education College of Life SciencesSichuan UniversityChengdu 610064China College of Chemistry Sichuan UniversityChengdu 610064China

Twenty-seven novel pyrazole carboxamides with diarylamine-modified scaffold were designed,synthesized and characterized in detail via1 H NMR,^（13） C NMR, IR and ESI-HRMS. Preliminary bioassays showed that some of the target compounds exhibited good antifungal activity against Rhizoctonia solani,Rhizoctonia cerealis and Sclerotinia sclerotiorum. Among them, compound 9c-7 exhibited the highest antifungal activities against R. solani, R. cerealis and S. sclerotiorum in vitro with IC_（50） values of 0.013, 1.608 and 1.874 mg/m L, respectively. Notably, compound 9c-7 still presented the highest fungicidal activities against R. solani in vivo with an IC_（50） value of 22.21 mg/m L. Molecular docking simulation results reveal that compound 9c-7 binds well to the hydrophobic pockets of the receptor protein succinate dehydrogenase. This study suggests that compound 9c-7 could act as a potential fungicide to be used for further optimization.

关键词： Pyrazole carboxamide Synthesis Antifungal activities Diarylamine