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Chemical Research in Chinese Universities 2021年第3期37卷 571-577页

作者： ZHENG Gaofeng PENG Hao JIANG Jiaxin kang Guoyi LIU Juan ZHENG Jianyi LIU yifang Department of Instrumental and Electrical Engineering Xiamen UniversityXiamen361102P.R.China Fujian Innovation Center of Additive Manufacturing Fuzhou350118P.R.China

Convenient and integration fabrication process is a key issue for the application of functional nanofibers.A surface functionalization method was developed based on coaxial electrospinning to produce ultraviolet(UV)protection *** titanium dioxide(TiO_(2))nanoparticles suspension was delivered through the shell channel of the coaxial spinneret,by which the aggregation of TiO_(2) nanoparticles was overcome and the distribution uniformity on the surface of polyethylene oxide(PEO)nanofiber was *** the content of TiO_(2) increasing from 0 to 3%(mass fraction),the average diameter of nanofibers increased from(380±30)nm to(480±100)*** surface functionalization can be realized during the electrospinning process to gain PEO/TiO_(2) composite nanofibers *** uniform distribution of TiO_(2) nanoparticles on the surface of nanofibers enhanced the UV absorption and resistance *** maximum UV protection factor(UPF)value of composite nanofibers reaches *** work presented a novel surface-functionalized way for the preparation of composite nanofiber,which has great application potential in the field of micro/nano system integration fabrication.

关键词： Coaxial electrospinning Surface functionalization TiO_(2)nanoparticle Composite nanofiber UV protection

Simulated annealing spectral clustering algorithm for image segmentation

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Journal of Systems Engineering and Electronics 2014年第3期25卷 514-522页

作者： yifang Yang Yuping Wang School of Mathematics and Statistics Xidian University College of Science Xi'an Shiyou University School of Computer Science and Technology Xidian University

The similarity measure is crucial to the performance of spectral clustering. The Gaussian kernel function based on the Euclidean distance is usual y adopted as the similarity measure. However, the Euclidean distance measure cannot ful y reveal the complex distribution data, and the result of spectral clustering is very sensitive to the scaling parameter. To solve these problems, a new manifold distance measure and a novel simulated anneal-ing spectral clustering （SASC） algorithm based on the manifold distance measure are proposed. The simulated annealing based on genetic algorithm （SAGA）, characterized by its rapid convergence to the global optimum, is used to cluster the sample points in the spectral mapping space. The proposed algorithm can not only reflect local and global consistency better, but also reduce the sensitivity of spectral clustering to the kernel parameter, which improves the algorithm’s clustering performance. To efficiently apply the algorithm to image segmentation, the Nystrom method is used to reduce the computation complexity. Experimental results show that compared with traditional clustering algorithms and those popular spectral clustering algorithms, the proposed algorithm can achieve better clustering performances on several synthetic datasets, texture images and real images.

关键词： spectral clustering (SC) simulated annealing (SA) image segmentation Nystr6m method.

川芎嗪含药血清通过抑制抗氧化能力在肝癌HepG2细胞中发挥抗肿瘤作用

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医学分子生物学杂志 2025年第1期22卷 35-40页

作者：张义芳戴毅遂宁市中心医院肝胆外科四川省遂宁市629000

目的探究川芎嗪(tetramethylpyrazine,TMP)含药血清对肝癌细胞增殖的影响及其机制。方法制备SD大鼠0、30、60、120 mg/kg TMP含药血清,并分别处理HepG2细胞,克隆形成和CCK-8法检测HepG2细胞的增殖;流式细胞术检测HepG2细胞周期和凋亡,流... 详细信息

目的探究川芎嗪(tetramethylpyrazine,TMP)含药血清对肝癌细胞增殖的影响及其机制。方法制备SD大鼠0、30、60、120 mg/kg TMP含药血清,并分别处理HepG2细胞,克隆形成和CCK-8法检测HepG2细胞的增殖;流式细胞术检测HepG2细胞周期和凋亡,流式JC-1检测HepG2细胞线粒体膜电位变化,蛋白质印迹检测HepG2细胞中PCNA、P27、cleaved caspase-3(cas-3),Bax,Bcl-2和Cyt C的表达;试剂盒检测HepG2细胞中SOD和MDA的含量;2,7-二氯二乙酸酯(DCFH-DA)测定HepG2细胞中活性氧(reactive oxygen species,ROS)的产生。结果与对照组比较,TMP 60、120 mg/kg组细胞增殖能力受抑制,细胞周期受阻滞;凋亡率明显升高;抗氧化能力受抑制。结论TMP可抑制肝癌细胞的增殖,并通过线粒体依赖途径诱导肝癌细胞凋亡,刺激ROS的生成降低癌细胞抗氧化能力,从而抑制肝癌的发展。

关键词：肝癌川芎嗪增殖细胞凋亡线粒体活性氧

GPS: graph contrastive learning via multi-scale augmented views from adversarial pooling

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Science China(Information Sciences) 2025年第1期 145-158页

作者： Wei JU Yiyang GU Zhengyang MAO Ziyue QIAO yifang QIN Xiao LUO Hui XIONG Ming ZHANG School of Computer Science National Key Laboratory for Multimedia Information ProcessingPeking University Artificial Intelligence Thrust The Hong Kong University of Science and Technology Department of Computer Science University of California

Self-supervised graph representation learning has recently shown considerable promise in a range of fields, including bioinformatics and social networks. A large number of graph contrastive learning approaches have shown promising performance for representation learning on graphs, which train models by maximizing agreement between original graphs and their augmented views(i.e., positive views). Unfortunately, these methods usually involve pre-defined augmentation strategies based on the knowledge of human experts. Moreover, these strategies may fail to generate challenging positive views to provide sufficient supervision signals. In this paper, we present a novel approach named graph pooling contrast(GPS) to address these *** by the fact that graph pooling can adaptively coarsen the graph with the removal of redundancy, we rethink graph pooling and leverage it to automatically generate multi-scale positive views with varying emphasis on providing challenging positives and preserving semantics, i.e., strongly-augmented view and weakly-augmented view. Then, we incorporate both views into a joint contrastive learning framework with similarity learning and consistency learning, where our pooling module is adversarially trained with respect to the encoder for adversarial robustness. Experiments on twelve datasets on both graph classification and transfer learning tasks verify the superiority of the proposed method over its counterparts.

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Characteristic of Torsional Vibration of Mill Main Drive Excited by Electromechanical Coupling

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Chinese Journal of Mechanical Engineering 2016年第1期29卷 180-187页

作者： ZHANG yifang YAN Xiaoqiang LIN Qihui Institute of Mechanical Engineering University of Science and Technology Beijing School of Mechanical Engineering Anhui University of Technology

In the study of electromechanical coupling vibration of mill main drive system, the influence of electrical system on the mechanical transmission is considered generally, however the research for the mechanism of electromechanical interaction is lacked. In order to research the electromechanical coupling resonance of main drive system on the F3 mill in a plant, the cycloconverter and synchronous motor are modeled and simulated by the MTLAB/SIMUL1NK firstly, simulation result show that the current harmonic of the cycloconverter can lead to the pulsating torque of motor output. Then the natural characteristics of the mechanical drive system are calculated by ANSYS, the result show that the modal frequency contains the component which is close to the coupling vibration frequency of 42Hz. According to the simulation result of the mechanical and electrical system, the closed loop feedback model including the two systems are built, and the mechanism analysis of electromechanical coupling presents that there is the interaction between the current harmonic of electrical system and the speed of the mechanical drive system. At last, by building and computing the equivalent nonlinear dynamics model of the mechanical drive system, the dynamic characteristics of system changing with the stiffness, damping coefficient and the electromagnetic torque are obtained. Such electromechanical interaction process is suggested to consider in research of mill vibration, which can induce strong coupling vibration behavior in the rolling mill drive system.

关键词： rolling mill vibration current harmonic speed oscillation electromechanical coupling vibration characteristic

Genetics of T Cell Defects in Lupus

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Cellular & Molecular Immunology 2005年第6期2卷 403-409页

作者： yifang Chen Laurence Morel Department of Pathology Immunology and Laboratory Medicine University of Florida Gainesville Fl 32610 USA Department of Medicine University of California at San Diego San DiegoCA 92093 USA

Systemic lupus erythematosus （SLE） is an autoimmune disease characterized by anti-nuclear autoantibodies that cause damage to multiple organs and tissues. Intrinsic defects have been demonstrated in the lymphoid and myeloid cellular compartments, including T cells. Lupus susceptibility is mediated through the interplay of a large number of genes, most of which are still unidentified. Most of the genetic studies in both human patients and mouse models have addressed lupus susceptibility as a whole. More recently however, more attention has been paid to the inheritance of specific lupus-associated phenotypes. In this review, we summarized our results obtained with the Slel locus in the NZM2410 mouse model, which mediates the generation of anti-histone autoreactive T cells. Slel, which is constituted of multiple genes, is the only known genomic region that is sufficient for the generation of autoreactive T cells. The identification of the corresponding genes will constitute a landmark for our understanding of the mechanisms of autoimmunlty. Our results are discussed in the context of candidate genes and the role of T cells in systemic autoimmunlty. Cellular ＆ Molecular Immunology. 2005;2（6）：403-409.

关键词： autoimmunity T cell genetics lupus mouse model

DYNAMIC PRICE MODEL BASED ON TRANSMISSION DELAY——PETROLEUM PRICE FLUCTUATION IN CHINA

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Journal of Systems Science & Complexity 2014年第3期27卷 507-523页

作者： LIU yifang WANG Yue QIAO Heng Economics School Central University of Finance and Economics Research Center for Climate and Energy Finance CUFE School of Management University of Chinese Academy of Sciences China Development Bank

Petroleum is a kind of fundamental energy resource. Its price fluctuation transmits from upper-stream industry to the lower-stream industry as the production factors price changes. And this leads to the price changes of final consumption. Meantime, due to the cycle of industrial chain, the price changes of lower-stream industry also affect the upper-stream industry in return. This price transmission path is quite complicated. Firstly, it includes both direct and indirect paths; secondly, the transmission process is accompanied with time delay. The traditional input-output price model based on cost-push theory can efficiently solve the first problem when estimating the impact of price fluctuation on the whole price system. However, it neither reflects the dynamic characteristics of price transmission with time nor solves the second problem. To solve this problem, this paper uses the directed weighted network to describe the price transmission among industrial sectors by taking the time-dimension into account, and dynamic price transmission network model is constructed. This model not only describes transmission time delay more accurately, but also calculates the price fluctuation dynamically. On this basis, by utilizing the 2007 Chinese input-output table, this paper conducts empirical analysis on the impact of petroleum price fluctuation on other sectors. The empirical results indicate that the price fluctuation transmission mainly depends on two factors, the orice reaction period Tk and the consumption relationship with petroleum aik. 1） If t 〈 Tk, then the price change of sector k at period t △pkt = 0, the petroleum price fluctuation has not transmitted to the sector k, so the price of sector k remains unchanged. 2） If t 〉 Tk, then Apt 〉 0, and the greater aik, the higher price change rate. 3） If t →∞, it is the same with that in traditional input-output price model. So it can be clearly seen that dynamic price transmission network model is more general than the t

关键词： Directed weighted network input-output price model petroleum price transmission timedelay.

Real-time visualization of 3D city models at street-level based on visual saliency

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Science China Earth Sciences 2015年第3期58卷 448-461页

作者： MAO Bo BAN yifang Lars HARRIE Jiangsu Provincial Key Laboratory of E-Business Nanjing University of Finance and Economics College of Computer Science and Engineering Nanjing University of Science and Technology Department of Urban Planning and Environment KTH Royal Institute of TechnologySE-10044 StockholmSweden Department of Physical Geography and Ecosystem Science Lund UniversityBox118SE-223 62 LundSweden

Street-level visualization is an important application of 3D city *** to street-level visualization include the cluttering of buildings due to fine detail and visualization *** this paper,a novel method is proposed for streetlevel visualization based on visual saliency *** basic idea of the method is to preserve these salient buildings in a scene while removing those that are *** method can be divided into pre-processing procedures and real-time *** first step in pre-processing is to convert 3D building models at higher Levels of Detail(Lo Ds) into LoD 1 models with simplified ground ***,a number of index viewpoints are created along the streets; these indices refer to both the position and the direction of each street site.A visual saliency value is computed for each building,with respect to the index site,based on a visual difference between the original model and the generalized *** calculate and evaluate three methods for visual saliency:local difference,global difference and minimum projection *** real-time visualization process begins by mapping the observer to its closest *** street view is then generated based on the building information stored in those indexes.A user study shows that the local visual saliency method performs better than do the global visual saliency,area and image-based methods and that the framework proposed in this paper may improve the performance of 3D visualization.

关键词： 3D city models street level visualization index viewpoints visual saliency

Intrinsically high efficiency sodium metal anode

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Science China Chemistry 2020年第11期63卷 1557-1562页

作者： yifang Zhang Qiuwei Shi Yiren Zhong Hailiang Wang Department of Chemistry and Energy Sciences Institute Yale UniversityWest HavenCT 06516USA Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New CityFuzhou 350207China

Efficient plating/stripping of Na metal is critical to stable operation of any rechargeable Na metal ***,it is often overlooked or misunderstood in electrochemical measurements using thick Na electrodes with large excess of Na ***,we report two crucial aspects,which have generally been ignored in previous studies,in the development of more practical capacity-controlled Na metal electrodes that can be efficiently cycled at 100%*** find that common carbonate electrolytes induce severe side reaction and highly irreversible Na plating/stripping,whereas ether electrolytes without any additive support thick Na metal electrodes operating at a high average Coulombic efficiency of 99.6%for over 300 *** further show that to realize such high efficiency in thin Na metal electrodes,it is necessary to ensure strong adhesion between the thin Na layer and the Cu current collector,which we solve by introducing an Au *** resulting transferable thin Na metal electrodes enable high-energy-density,high-efficiency and reasonably stable-cycling Na||Na3V2(PO4)3 batteries.

关键词： sodium metal battery electrolyte Coulombic efficiency deep cycling

Artificial Intelligence Applications in the Development of Autonomous Vehicles:A Survey

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IEEE/CAA Journal of Automatica Sinica 2020年第2期7卷 315-329页

作者： yifang Ma Zhenyu Wang Hong Yang Lin Yang Department of Information Technology and Decision Sciences Old Dominion UniversityNorfolkVA 23529 USA Department of Computational Modeling and Simulation Engineering Old Dominion UniversityNorfolkVA 23529 USA Department of Mechanical and Electrical Engineering Huazhong Agricultural UniversityWuhan 430070China

The advancement of artificial intelligence(AI)has truly stimulated the development and deployment of autonomous vehicles(AVs)in the transportation *** by big data from various sensing devices and advanced computing resources,AI has become an essential component of AVs for perceiving the surrounding environment and making appropriate decision in *** achieve goal of full automation(i.e.,self-driving),it is important to know how AI works in AV *** research have made great efforts in investigating different aspects of applying AI in AV ***,few studies have offered the research community a thorough examination of current practices in implementing AI in ***,this paper aims to shorten the gap by providing a comprehensive survey of key studies in this research ***,it intends to analyze their use of AIs in supporting the primary applications in AVs:1)perception;2)localization and mapping;and 3)decision *** investigates the current practices to understand how AI can be used and what are the challenges and issues associated with their *** on the exploration of current practices and technology advances,this paper further provides insights into potential opportunities regarding the use of AI in conjunction with other emerging technologies:1)high definition maps,big data,and high performance computing;2)augmented reality(AR)/virtual reality(VR)enhanced simulation platform;and 3)5G communication for connected *** paper is expected to offer a quick reference for researchers interested in understanding the use of AI in AV research.

关键词： Artificial intelligence(AI) autonomous vehicles(AVs) deep learning(DL) motion planning perception self-driving