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Feature Extraction and Dimensionality Reduction of Arc Sound under Typical Penetration Status in Metal Inert Gas Welding

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Chinese Journal of Mechanical Engineering 2012年第2期25卷 293-298页

作者： LIU Lijun lan Hu ZHENG Hongyan JIAN Xiaoxia Ningbo Institute of Technology Zhejiang UniversityNingbo 315100China School of Material Science ＆ Engineering Harbin University of Science and TechnologyHarbin 150080China Rongcheng College Harbin University of Science and TechnologyRongcheng 264300China

Arc sound is well known as the potential and available resource for monitoring and controlling of the weld penetration status,which is very important to the welding process quality control,so any attentions have been paid to the relationships between the arc sound and welding *** non-linear mapping models correlating the arc sound to welding parameters have been established with the help of neural ***,the research of utilizing arc sound to monitor and diagnose welding process is still in its infancy.A self-made real-time sensing system is applied to make a study of arc sound under typical penetration status,including partial penetration,unstable penetration,full penetration and excessive penetration,in metal inert-gas（MIG） flat tailored welding with spray *** sound is pretreated by using wavelet de-noising and short-time windowing technologies,and its characteristics,characterizing weld penetration status,of time-domain,frequency-domain,cepstrum-domain and geometric-domain are ***,high-dimensional eigenvector is constructed and feature-level parameters are successfully fused utilizing the concept of primary principal component analysis（PCA）.Ultimately,60-demensional eigenvector is replaced by the synthesis of 8-demensional vector,which achieves compression for feature space and provides technical supports for pattern classification of typical penetration status with the help of arc sound in MIG welding in the future.

关键词： metal inert gas welding penetration arc sound feature extraction dimensionality reduction

Finding Deceptive Opinion Spam by Correcting the Mislabeled Instances

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Chinese Journal of Electronics 2015年第1期24卷 52-57页

作者： REN Yafeng JI Donghong YIN lan ZHANG Hongbin School of Computer Wuhan University

Assessing the trustworthiness of reviews is a key in natural language processing and computational linguistics. Previous work mainly focuses on some heuristic strategies or simple supervised learning methods, which limit the performance of this task. This paper presents a new approach, from the viewpoint of correcting the mislabeled instances, to find deceptive opinion spam. Partition a dataset into several subsets, construct a classifier set for each subset and select the best one to evaluate the whole dataset. Error variables are defined to compute the probability that the instances have been mislabeled. The mislabeled instances are corrected based on two threshold schemes, ma jority and non-objection. The results display significant improvements in our method in contrast to the existing baselines.

关键词： Deceptive opinion spam Mislabeled instances Machine learning Computational linguistics.

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微生物种间直接电子传递研究进展

应用生态学报 2021年第1期32卷 358-368页

作者：兰建英蒋海明李侠内蒙古科技大学生命科学与技术学院内蒙古包头014010 内蒙古自治区生物质能源化利用重点实验室内蒙古包头014010 内蒙古科技大学矿业研究院内蒙古包头014010

一直以来氢气和甲酸被认为是微生物间电子传递的中间电子传递体。近年来的研究发现,微生物之间可以通过种间直接电子传递(DIET)来替代氢气/甲酸传递。DIET作为一种新发现的微生物间电子传递途径,其电子传递效率要高于传统的种间氢气/甲... 详细信息

一直以来氢气和甲酸被认为是微生物间电子传递的中间电子传递体。近年来的研究发现,微生物之间可以通过种间直接电子传递(DIET)来替代氢气/甲酸传递。DIET作为一种新发现的微生物间电子传递途径,其电子传递效率要高于传统的种间氢气/甲酸传递。DIET这一新发现改变了微生物互营生长代谢必须依赖氢气或甲酸等电子载体的传统认识,为今后研究微生物互营现象打开了新视角。虽然DIET研究取得了很大进展,但是目前对能够进行DIET的微生物种类、DIET机制及影响DIET的因素尚缺乏深入研究。本文首先概述了能形成DIET的微生物,然后重点分析了能够进行DIET的电子供体微生物胞外电子传递的机制和电子受体微生物直接利用胞外电子的分子机制,最后阐述了导电材料对DIET的影响,并提出了DIET今后的研究方向,旨在为DIET研究提供参考。

关键词：种间直接电子传递电子供体微生物电子受体微生物互营生长导电材料胞外电子传递机制

Review of hand, foot and mouth disease

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Frontiers of Medicine 2010年第2期4卷 139-146页

作者： lan-Juan LI State Key Laboratory for Diagnosis and Treatment of Infectious Diseases The First Affiliated HospitalCollege of MedicineZhejiang UniversityHangzhou 310003China

Hand,foot and mouth disease(HFMD)is an acute viral illness that primarily affects infants and young children,and often occurs in clusters or *** major causative agents of HFMD are coxsackievirus A16(CVA16),human enterovirus 71(HEV71)and coxsack-ievirus A10(CVA10),of the genus Enterovirus in the family *** caused by EV71 is associated with severe neurological complications and *** the late 1990s,several major epidemics of EV71 HFMD have swept through the Asia-Paciﬁc region,associated with a rapid fulminant course,severe neurolo-gical complications,and a large number of *** now,little has been known about the genetics and transmission trends of the fast-mutation virus,and there is no effective and speciﬁc antiviral therapy or vaccine for *** is time to step up efforts to understand the molecular epidemics and pathogenesis so that we can develop effective management strategies and surveillance programs.

关键词： hand,foot and mouth disease epidemiology pathogenesis management surveillance

Static and Dynamic Analyses of Composite Beam Bonded with MFC Actuator

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Journal of Harbin Institute of Technology(New Series) 2020年第2期27卷 75-86页

作者： Ke Wu Houfei Fang lan lan Xi’an Institution of Space Radio Technology Xi’an 710100China Shanghai YS Information Technology Co. Ltd.Shanghai 200240China

Investigated by this study is an MFC actuator attached to the surface of a Carbon Fiber Reinforced Polymer(CFRP)composite beam to form a beam actuator *** capturing the characteristics of such system is essential.A novel analytical methodology considering the transverse shear strain and active stiffening effect is proposed,which was newly applied to analyze the static and dynamic behaviors of the beam actuator *** governing equations of the beam actuator system were obtained via generalized Hamilton’s principle.A distributed transfer function formulation was ***,the closed form solution was derived by using the Green’s *** response,natural frequencies,and modal shapes of the beam actuator system were *** solution is analytical without using any truncated series or admissible functions at any arbitrary boundary *** Element Method(FEM)results were also obtained to compare with that of the proposed *** predictions of the analyses were verified experimentally,which shows the correctness and effectiveness of the proposed method.

关键词： Macro Fiber Composites(MFC) Carbon Fiber Reinforced Polymer(CFRP) distributed transfer function formulation Green’s function

Seismic behavior of large-scale FRP–recycled aggregate concrete–steel columns with shear connectors

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Earthquake Engineering and Engineering Vibration 2019年第4期18卷 823-844页

作者： Zeng lan Li Lijuan Yang Xianqian Liu Feng School of Civil and Transportation Engineering Guangdong University of Technology Guangzhou 510006 China MOE Key Laboratory of Disaster Forecast and Control in Engineering School of Mechanics and Construction Engineering Jinan University Guangzhou 510632 China Architectural Design and Research Institute of Guangdong Province Guangzhou 510000 China

The application of fi ber-reinforced polymer (FRP) composites for the development of high-performance composite structural systems has received signifi cant recent research attention. A composite of FRP–recycled aggregate concrete (RAC)–steel column (FRSC), consisting of an outer FRP tube, an inner steel tube and annular RAC fi lled between two tubes, is proposed herein to facilitate green disposal of demolished concrete and to improve the ductility of concrete columns for earthquake resistance. To better understand the seismic behavior of FRSCs, quasi-static tests of large-scale basalt FRSCs with shear connectors were conducted. The infl uence of the recycled coarse aggregate (RCA) replacement percentage, shear connectors and axial loading method on the lateral load and deformation capacity, energy dissipation and cumulative damage were analyzed to evaluate the seismic behavior of FRSCs. The test results show that FRSCs have good seismic behavior, which was evidenced by high lateral loads, excellent ductility and energy dissipation capacity, indicating RAC is applicable in FRSCs. Shear connectors can signifi cantly postpone the steel buckling and increase the lateral loads of FRSCs, but weaken the deformation capacity and energy dissipation performance.

关键词： recycled aggregate concrete (RAC) fi ber-reinforced polymer (FRP) FRP–RAC–steel column (FRSC) shear connector seismic behavior

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真空绝热板芯材的研究进展与展望

化工进展 2024年第7期43卷 3910-3922页

作者：赵伟刚张倩倩蓝钰玲闫雯周晓剑范毜仔杜官本福建农林大学材料工程学院福建福州350002 西南林业大学生物质材料国际联合研究中心云南昆明650224 英国布鲁内尔大学土木工程系英国伦敦UB83PH

随着我国经济的迅速发展和人们对生活水平的要求越来越高,节能减排对实现“碳达峰”和“碳中和”的目标显得越来越重要。真空绝热板(vacuum insolation panels,VIP)是一种新型的高效保温隔热材料,其中,芯材作为VIP的核心和骨架结构,不... 详细信息

随着我国经济的迅速发展和人们对生活水平的要求越来越高,节能减排对实现“碳达峰”和“碳中和”的目标显得越来越重要。真空绝热板(vacuum insolation panels,VIP)是一种新型的高效保温隔热材料,其中,芯材作为VIP的核心和骨架结构,不仅承担着支撑作用,而且是板内热量传递的主要通道,对保证VIP的保温性能具有关键作用。基于此,本文首先重点介绍了真空绝热板在绿色建筑和冷链物流领域应用的意义,明确了目前制约真空绝热板领域发展的关键问题;随后综述了真空绝热板芯材的研究现状和进展,比对了不同种类芯材(颗粒类芯材、泡沫类芯材、纤维类芯材、生物质材料类芯材和复合类芯材)在原料来源、保温性能、生产工艺及环境保护方面的优劣,将绿色、可再生的生物质基材料用作真空绝热板芯材进行了对比探讨;最后对真空绝热板芯材未来的研究方向和发展前景进行了总结和展望。本文指出,传统以玻璃纤维、有机泡沫或者气相二氧化硅为芯材的真空绝热板,存在生产成本高、不可再生、难降解、污染环境等问题,所以通过功能化手段获得新型、绿色、低成本、具有良好微观孔隙结构和高热阻的芯材是制约真空绝热板发展的关键。生物质材料具有来源广泛、成本低廉、绿色环保、孔隙结构丰富等优点,是一种极具潜力的VIP芯材原料,也将是真空绝热板芯材的重要研究方向。因此,生物质基芯材真空绝热板未来的发展还需进一步拓宽其原料来源、改善制备方法和工艺、明确老化和使役性能、关注复合芯材的开发,不断提高VIP的性能,扩展其应用领域。

关键词：真空绝热板芯材保温性能传热生物质热传导复合材料

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经皮氧分压/二氧化碳分压监测对重症监护患者压力性损伤发生的早期预警价值

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中华急诊医学杂志 2024年第5期33卷 698-703页

作者：郭志强蓝健邓一砾王晓川王云王永春中国科学院大学深圳医院重症医学科深圳518107

目的探讨经皮氧分压/二氧化碳分压(TcPO_(2)/TcPCO_(2))监测在重症监护患者压力性损伤发生的早期风险预警价值。方法采用前瞻性临床观察研究,选取2020年12月至2022年6月依次入住中国科学院大学深圳医院(光明)重症医学科的患者为研究对象... 详细信息

目的探讨经皮氧分压/二氧化碳分压(TcPO_(2)/TcPCO_(2))监测在重症监护患者压力性损伤发生的早期风险预警价值。方法采用前瞻性临床观察研究,选取2020年12月至2022年6月依次入住中国科学院大学深圳医院(光明)重症医学科的患者为研究对象,记录患者的一般资料,分别监测患者在左侧卧位、仰卧位和右侧卧位时的TcPO_(2)、TcPCO_(2)。根据重症患者的Braden评分将入住患者分为低危组和高危组,分析TcPO_(2)/TcPCO_(2)监测结果。结果本研究共纳入80例患者,低危组(46例)和高危组(34例)的性别、年龄差异均无统计学意义(均P>0.05),两组的Braden评分、压力性损伤发生率差异均有统计学意义(均P0.05)。结论TcPO_(2)、TcPCO_(2)和TcPO_(2)/TcPCO_(2)值对重症监护患者的压力性损伤均具有较高的诊断价值。TcPO_(2)/TcPCO_(2)监测对重症监护患者压力性损伤的发生有早期风险预警价值,具有临床推广意义。

关键词：压力性损伤经皮氧分压经皮二氧化碳分压 Braden评分重症医学科

Ag-catalyzed Synthesis of Tb（BO2）3 Nanorods

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Chinese Journal of Chemical Physics 2010年第6期23卷 713-718,746页

作者：杨兰周立群黄莹唐子威湖北大学有机功能分子合成与应用教育部重点实验室武汉430062

Well-crystallized with excellent luminescent cessfully synthesized by a simple solid-state properties, Tb（BO2）3 nanorods were first suc- method with Ag as catalyst. The result of X- ray diffraction showed that the Tb（BO2）3 nanorods could be well-crystallized at 700 ℃. As-prepared straight nanorods of Tb（BO2）3 had the typical diameters in the range of 100-200 nm, the thickness of 30 50 nm, and the length up to 3 μm by transmission electron microscopy, and the corresponding selected area electron diffraction indicated that the nanorod calcined at 700 ℃ was single-crystalline. Based on the fact that Ag nanoparticles attached to the tips and middles of the Tb（BO2）3 nanorods, a growth model of the Tb（BO2）3 nanorods was proposed. Photoluminescence spectra under excitation at 369 nm showed that these Tb（BO2）3 phosphors had a green emission at 546 nm, which is ascribed to 5D4→7F5 transition. The effect of calcining temperature on the structures, morphologies, and luminescent properties of Tb（BO2）3 phosphors were studied.

关键词： Crystal growth Growth from vapor Nanostructure Phosphor