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Instance selection method for improving graph-based semi-supervised learning

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Frontiers of Computer Science 2018年第4期12卷 725-735页

作者： Hai WANG Shao-Bo WANG Yu-Feng LI 1 National Key Laboratory for Novel software Technology Nanjing University Nanjing 210023 China Collaborative Innovation center of Novel software Technology and Industrialization Nanjing 210023 China

Graph-based semi-supervised learning is an important semi-supervised learning paradigm. Although graphbased semi-supervised learning methods have been shown to be helpful in various situations, they may adversely affect performance when using unlabeled data. In this paper, we propose a new graph-based semi-supervised learning method based on instance selection in order to reduce the chances of performance degeneration. Our basic idea is that given a set of unlabeled instances, it is not the best approach to exploit all the unlabeled instances; instead, we should exploit the unlabeled instances that are highly likely to help improve the performance, while not taking into account the ones with high risk. We develop both transductive and inductive variants of our method. Experiments on a broad range of data sets show that the chances of performance degeneration of our proposed method are much smaller than those of many state-of-the-art graph-based semi-supervised learning methods.

关键词： graph-based semi-supervised learning performance degeneration instance selection

A Multi-Agent Spatial Logic for Scenario-Based Decision Modeling and Verification in Platoon Systems

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Journal of Computer Science & Technology 2021年第6期36卷 1231-1247页

作者： Jingwen Xu Yanhong Huang Jianqi Shi Shengchao Qin National Trusted Embedded software Engineering Technology Research center East China Normal University Shanghai 200062China College of Computer Science and software Engineering Shenzhen UniversityShenzhen 518061China

To cater for the scenario of coordinated transportation of multiple trucks on the highway,a platoon system for autonomous driving has been extensively explored in the *** such a platoon is deployed,it is necessary to ensure the safety of its driving behavior,whereby each vehicle’s behavior is commanded by the decision-making function whose decision is based on the observed driving ***,there is currently a lack of verification methods to ensure the reliability of the scenario-based decision-making process in the platoon *** this paper,we focus on the platoon driving scenario,whereby the platoon is composed of intelligent heavy trucks driving on cross-sea *** propose a formal modeling and verification approach to provide safety assurance for platoon vehicles’cooperative driving *** existing Multi-Lane Spatial Logic(MLSL)with a dedicated abstract model can express driving scene spatial properties and prove the safety of multi-lane traffic maneuvers under the single-vehicle *** cater for the platoon system’s multi-vehicle perspective,we modify the existing abstract model and propose a Multi-Agent Spatial Logic(MASL)that extends MLSL by relative orientation and multi-agent *** then utilize a timed automata type supporting MASL formulas to model vehicles’decision controllers for platoon *** the behavior of a human-driven vehicle(HDV)joining the platoon as a case study,we have implemented the model and verified safety properties on the UPPAAL tool to illustrate the viability of our framework.

关键词： autonomous driving decision-making model platoon system safety verification timed automaton

A sensitive and compact mercury analyzer by integrating dielectric barrier discharge induced cold vapor generation and optical emission spectrometry

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Chinese Chemical Letters 2017年第2期28卷 189-196页

作者： An-Qin Leng Yun-Fei Tian Ming-Xuan Wang Li Wu Kai-Lai Xu Xian-Deng Hou Cheng-Bin Zheng College of Chemistry Sichuan University Chengdu 610064 China Analytical & testing center Sichuan University Chengdu 610064 China

An environmentally friendly,low power consuming,sensitive and compact mercury analyzer was developed for the determination of mercury in water samples by integrating a thin film dielectric barrier discharge induced cold vapor reactor and a dielectric barrier discharge optical emission spectrometer into a small polymethyl methacrylate plate（10.5 cm length×8.0 cm width×1.2 cm height）.Mercury cold vapor was generated when standard or sample solutions with or without formic acid were introduced to the reactor to form thin film liquid and exposed to microplasma irradiation and subsequently separated from the liquid phase for transport to the microplasma and detection of its atomic *** of detection of 0.20 μg L^-1 and 2.6 μg L^-1 were obtained for the proposed system using or not using formic acid,*** to the conventional microplasma optical emission spectrometry used for mercury analysis,this system not only retains the good limit of detection amenable to the determination of mercury in real samples,but also reduces power consumption,eliminates the generation of hydrogen and avoids the use of toxic or unstable *** validation was demonstrated by analysis of a certified reference material of water sample and three real water samples with good spike recoveries（88-102%）.

关键词： Mercury Real time field analysis Microplasma Optical emission spectrometry Cold vapor generation Miniaturization

Argon Plasma-Induced Graft Polymerization of PEGMA on Chitosan Membrane Surface for Cell Adhesion Improvement

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Plasma Science and Technology 2013年第10期15卷 1041-1046页

作者： YIN Shiheng REN Li WANG Yingjun Analytical and testing center South China University of Technology Cuangzhou 510640China College of Materials Science and Engineering South China University of TechnologyGuangzhou 510640 China

For its biocompatibility and biodegradability, chitosan has had considerable atten- tion for biomedical applications in recent years. In this paper, polymerization of poly （ethylene glycol） methyl ether methacrylate （PEGMA） was grafted onto chitosan membrane surface through argon plasma-induced graft polymerization. The surface properties after modification were characterized by contact angle measurement, X-ray photoelectron spectroscopy （XPS） and atomic force microscopy （AFM）, respectively. The results indicated that PEGMA can be grafted successfully onto chitosan membrane surface. The surface hydrophilicity and free energy were improved and the surface roughness increased after modification. The adhesion of a human corneal epithelial cell （HCEC） on chitosan membrane surface was enhanced due to improvement of surface free energy and roughness.

关键词： chitosan membrane PEGMA plasma surface energy cell adhesion

ESTIMATION OF BLENDING RATIO OF TWO-COMPONENT FIBER BUNDLE FROM BUNDLE LOAD-ELONGATION CURVE

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Journal of china Textile University(English Edition) 1989年第1期7卷 1-9页

作者：严灏景王国强 Fiber Science testing center

In this paper, two methods were developed to assess the blending ratio of two-componentfiber bundles. They were the peak-height method and the slope method. The relationship be-tween blending ratio and testing data was analysed, and the regression curves were obtained bystepwise regression method. It was pointed out that the testing errors of both methods were lessthan two percent. The validities of both methods were verified by experiments, All calculationsof both methods were completed by computer. The blending ratio was ascertained from the test-ing data of bundle fiber strength tester which was made by the authors themselves.

关键词： two-component fiber bundle tensile properties blending ratio pcak-height method slope method regression curve

A quantitative research on the level of disturbance to secondary signal ports of electronic voltage transformers under the operation of gas‐insulated switchgear

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High Voltage 2022年第1期7卷 165-175页

作者： Qi Wang Chao Fu Fanwu Chu Yue Tong Xiaozhou Wang Guoxiong Ye Xiong Wu Power Industry Electrical Equipment Quality Inspection and testing center China Electric Power Research InstituteWuhanChina

The collectors of electronic transformers has the problem of electromagnetic in-compatibility under the operation of disconnecting switches,which limits their wide application in smart *** evaluate the maximum level of disturbance that collectors are able to withstand in the stochastic process of switching operation,this work in-troduces a quantitative approach based on limited test measurements,which can quantify the level of disturbance in the signal acquisition ports of electronic voltage transformers(EVT)in different gas‐insulated switchgears(GIS).Based on large numbers of experi-mental statistical data of the true type simulation experimental platform,the Spearman rank correlation coefficient is used to prove that the amplitude of the disturbance voltage pulse at the secondary side port and the breakdown voltage between the primary side fracture approximately satisfy a linear ***,the quantile regression model is used to quantify and verify the maximum disturbance level of the secondary side ***,a solution is proposed to tackle the difficulty in obtaining the breakdown voltage at breaks in the GIS substation field applicatvion,under which the quantified maximum disturbance voltage deviation of secondary ports is only−4.34%by *** research work can further explore the practical value of the measured data in a few tests under GIS substation field conditions and provide references for the sub-sequent revision of EVT‐related standards.

关键词： disturbance operation electronic

Development of MEMS-based micro capacitive tactile probe

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Chinese Physics B 2014年第11期23卷 646-650页

作者：雷李华李源范国芳吴俊杰简黎蔡潇雨李同保 School of Physics Science and Engineering Tongji University Shanghai Institute of Measurement and testing Technology National Center of Measurement and Testing for East China National Center of Testing Technology Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and Chemistry Chinese Academy of Sciences

In this paper, a micro capacitive sensor with nanometer resolution is presented for ultra-precision measurement of micro components, which is fabricated by the MEMS （micro electromechanical systems） non-silicon technique. Based on the sensor, a micro capacitive tactile probe is constructed by stylus assembly and packaging design for dimension metrology on micro/nano scale, in which a data acquiring system is developed with AD7747. Some measurements of the micro capacitive tactile probe are performed on a nano positioning and measuring machine （NMM）. The measurement results show good linearity and hysteresis with a range of 11.6 μm and resolution of better than 5 nm. Hence, the micro capacitive tactile probe can be integrated on NMM to realize measurement of micro structures with nanometer accuracy.

关键词： micro tactile probe micro capacitive sensor MEMS nano measuring machine

Electrospinning/3D printing-integrated porous scaffold guides oral tissue regeneration in beagles

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Bio-Design and Manufacturing 2024年第6期7卷 1000-1017页

作者： Li Yuan Chen Yuan Jiawei Wei Shue Jin Yi Zuo Yubao Li Xinjie Liang Jidong Li Research center for Nano-Biomaterials Analytical and Testing CenterSichuan UniversityChengdu 610064China ZXTGY(Jiangsu)Technology Co. Ltd.Suzhou 215400China

The combined use of guided tissue/bone regeneration(GTR/GBR)membranes and bone filling grafts represents a classical therapy for guiding the regeneration and functional reconstruction of oral soft and hard ***,due to its displacement and poor mechanical support,bone meal is not suitable for implantation in the case of insufficient cortical bone support and large dimensional *** combination of GTR/GBR membrane with a three-dimensional(3D)porous scaffold may offer a resolution for the repair and functional reconstruction of large soft and hard tissue *** this study,a novel integrated gradient biodegradable porous scaffold was prepared by bonding a poly(lactic-co-glycolic acid)(PLGA)/fish collagen(FC)electrospun membrane(PFC)to a 3D-printed PLGA/nano-hydroxyapatite(HA)(PHA)*** consistency of the composition(PLGA)ensured strong interfacial bonding between the upper fibrous membrane and the lower 3D *** vitro cell experiments showed that the PFC membrane(upper layer)effectively prevented the unwanted migration of L929 *** in vivo investigations with an oral soft and hard tissue defect model in beagles revealed that the integrated scaffold effectively guided the regeneration of defective oral *** results suggest that the designed integrated scaffold has great potential for guiding the regeneration and reconstruction of large oral soft and hard tissues.

关键词： Electrospinning 3D printing Gradient porous scaffold Oral tissue regeneration

Analyses for specific defects in Android applications:a survey

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Frontiers of Computer Science 2019年第6期13卷 1210-1227页

作者： Tianyong WU Xi DENG Jun YAN Jian ZHANG State Key Laboratory of Computer Science Institute of SoftwareChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Technology center of software Engineering Institute of SoftwareChinese Academy of SciencesBeijing 100190China

Android applications(APPS)are in widespread use and have enriched our *** ensure the quality and security of the apps,many approaches have been proposed in recent years for detecting bugs and defects in the apps,of which program analysis is a major *** paper mainly makes an investigation of existing works on the analysis of Android *** summarize the purposes and proposed techniques of existing approaches,and make a taxonomy of these works,based on which we point out the trends and challenges of research in this *** our survey,we sum up four main findings:(1)program analysis in Android security field has gained particular attention in the past years,the fields of functionality and performance should also gain proper attention;the infrastructure that supports detection of various defects should be enriched to meet the industry’s need;(2)many kinds of defects result from developers’misunderstanding or misuse of the characteristics and mechanisms in Android system,thus the works that can systematically collect and formalize Android recommendations are in demand;(3)various program analysis approaches with techniques in other fields are applied in analyzing Android apps;however,they can be improved with more precise techniques to be more applicable;(4)The fragmentation and evolution of Android system blocks the usability of existing tools,which should be taken into consideration when developing new approaches.

关键词： Android apps program analysis security functionality performance