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The Indirect Shared Steering Control Under Double Loop Structure of Driver and Automation

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IEEE/CAA Journal of Automatica Sinica 2020年第5期7卷 1403-1416页

作者： Yantao Tian Yanbo Zhao Yiran Shi Xuanhao Cao ding-li yu Department of Control Science and Engineering and also with the Key Laboratory of Bionic Engineering of Ministry of EducationJilin UniversityChangchun 130022China the Xi’an Jiaotong University Xi’an 710049China Department of Control Science and Engineering Jilin UniversityChangchun 130022China School of Engineering Liverpool John Moores UniversityLiverpool L33AFU.K.and also with the Department of Control Science and EngineeringJilin UniversityChangchun 130022China

Due to the critical defects of techniques in fully autonomous vehicles,man-machine cooperative driving is still of great significance in today’s transportation *** the previous shared control structure,this paper introduces a double loop structure which is applied to indirect shared steering control between driver and *** contrast to the tandem indirect shared control,the parallel indirect shared control put the authority allocation system of steering angle into the framework to allocate the corresponding weighting coefficients reasonably and output the final desired steering angle according to the current deviation of vehicle and the accuracy of steering ***,the active disturbance rejection controller(ADRC)is also added in the frame in order to track the desired steering angle fleetly and accurately as well as restrain the internal and external disturbances effectively which including the steering friction torque,wind speed and ground interference ***,we validated the advantages of double loop framework through three sets of double lane change and slalom experiments,*** as we expected,the simulation results show that the double loop structure can effectively reduce the lateral displacement error caused by the driver or the controller,significantly improve the tracking precision and keep great performance in trajectory tracking characteristics when driving errors occur in one of driver and controller.

关键词： Active disturbance rejection controller(ADRC) authority allocation indirect shared control

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基于多标签语义分割的硬笔字笔画提取

计算机系统应用 2024年第9期33卷 174-182页

作者：余嘉云李丁宇徐占洋王晶弘林巍南京师范大学南京210023 南京信息工程大学南京210044 江苏少儿春互联教育科技有限公司南京技术研发中心南京210032

汉字作为中华文化的载体,因其复杂的结构区别于其他文字.笔画作为汉字的基本单元,在硬笔字评价中起到至关重要的作用.正确提取笔画,是硬笔字评价的首要步骤.现有的笔画提取方法多数是基于规则的,由于汉字的复杂性,这些规则通常无法顾及... 详细信息

汉字作为中华文化的载体,因其复杂的结构区别于其他文字.笔画作为汉字的基本单元,在硬笔字评价中起到至关重要的作用.正确提取笔画,是硬笔字评价的首要步骤.现有的笔画提取方法多数是基于规则的,由于汉字的复杂性,这些规则通常无法顾及所有特征,且在评价时无法根据笔顺等信息与模板字笔画匹配.为了解决这些问题,该文将笔画提取转化为多标签语义分割问题,提出了多标签语义分割模型(M-TransUNet),利用深度卷积模型以汉字为单位任务进行训练,保留了笔画原有结构,避免了笔画段组合的二义性,同时得到了硬笔字的笔顺,有利于笔画评价等下游任务.由于硬笔字图像只分为前景和背景,没有额外颜色信息,所以更容易产生FP(false positive)分割噪声.为解决此问题,本文还提出了一种针对笔画分割结果的局部平滑策略(local smooth strategy on stroke,LSSS),淡化噪声的影响.最后,本文对M-TransUNet的分割性能以及效率进行了实验,证明了本文算法在很小性能损失的情况下,极大地提升了效率.同时对LSSS算法进行了实验,证明其在FP噪声消除的有效性.

关键词：硬笔字笔画提取多标签语义分割局部平滑策略

Microearthquake reveals the lithospheric structure at midocean ridges and oceanic transform faults

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Journal of Oceanology and limnology 2024年第3期42卷 697-700页

作者： Zhiteng yu Jiabiao li Weiwei ding Key Laboratory of Submarine Geosciences&Second Institute of Oceanography Ministry of Natural ResourcesHangzhou 310012China

Mid-ocean ridge and oceanic transforms are among the most prominent features on the seafloor surface and are crucial for understanding seafloor spreading and plate tectonic dynamics,but the deep structure of the oceanic lithosphere remains poorly *** large number of microearthquakes occurring along ridges and transforms provide valuable information for gaining an indepth view of the underlying detailed seismic structures,contributing to understanding geodynamic processes within the oceanic *** studies have indicated that the maximum depth of microseismicity is controlled by the 600-℃***,this perspective is being challenged due to increasing observations of deep earthquakes that far exceed this suggested isotherm along mid-ocean ridges and oceanic transform *** mechanisms have been proposed to explain these deep events,and we suggest that local geodynamic processes(e.g.,magma supply,mylonite shear zone,longlived faults,hydrothermal vents,etc.)likely play a more important role than previously thought.

关键词： microearthquake mid-ocean ridge oceanic transform fault oceanic lithosphere thermal structure earthquake location

Prediction of the ^(13)C NMR Chemical Shifts of Stilbene Analogues by GIAO Method

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Chemical Research in Chinese Universities 2010年第6期26卷 1016-1019页

作者： XIE Hui-ding li yu-peng QIU Kai-xiong liU Bo CHEN Ya-ping Department of Chemistry School of Pharmaceutical Sciences Kunming Medical College Kunming 650500 P. R. China

After the geometry optimization at B3LYP/6-31＋G（d,p） level,the calculations of the NMR chemical shifts of a series of stilbene analogues were carried out by means of Gauge Including Atomic Orbitals（GIAO） method at HF/6-31＋G（d） level and B3LYP/6-311G＋（2d,p） level,*** 13C NMR chemical shifts calculated at both HF/6-31＋G（d） and B3LYP/6-31＋G（d,p） levels are in agreement with the observed *** virtue of a series of linear correction equations（δpred.=a＋bδcalcd.） of the 13C chemical shifts,accurate prediction of 13C chemical shifts was achieved for the new stilbene *** the 13C NMR chemical shifts calculated at HF/6-31＋G（d） level,the linear correlation of δ*** δ*** excellent,and the square of correlation coefficient,r2,is *** maximum absolute difference between δ*** δexptl.,Δδ,is 2.3,and the root-mean-square error between δ*** δ*** *** the meantime,for those obtained at B3LYP/6-31＋G（d,p） level,the linear correlation of δ*** δ*** also excellent,and the square of correlation coefficient,r2,is up to *** maximum absolute difference between δ*** δexptl.,Δδ,is 2.2,and the root-mean-square error between δ*** δ*** only 0.88.

关键词： Stilbene analogue ^13C NMR chemical shift Prediction

A Cooperative Schema between Web Sever and Search Engine for Improving Freshness of Web Repository

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Wuhan University Journal of Natural Sciences 2006年第1期11卷 11-14页

作者： WEN Kun-mei LU Zheng-ding li yu-hua SUN Xiao-lin College of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074Hubei China

Because the web is huge and web pages are updated frequently, the index maintained by a search engine has to refresh web pages periodically. This is extremely resource consuming because the search engine needs to crawl the web and download web pages to refresh its index, Based on present technologies of web refreshing, we present a cooperative schema between web server and search engine for maintaining freshness of web repository. The web server provides metadata defined through XML standard to describe web sites. Before updating the web page the crawler visits the meta-data files. If the meta-data indicates that the page is not modified, then the crawler will not update it. So this schema can save bandwidth resource. A primitive model based on the schema is implemented. The cost and efficiency of the schema are analyzed.

关键词： search engine freshness cooperative schema

Removal of copper from aqueous solutions by bentonites and the factors affecting it

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Mining Science and Technology 2009年第4期19卷 489-492页

作者： ding Shu-li SUN yu-zhuang YANG Cui-na XU Bo-hui Key Laboratory for Resources Reconnaissance of Hebei Province Hebei University of Engineering Handan Hebei 056038 China

In order to study the ability of bentonites to remove heavy metal ions from waste water and its factors affecting it,batch sorption experiments of Cu2+ were conducted on Ca-bentonite and Na-bentonite under various *** results show that the adsorption process of bentonite accorded with the Freundlich isotherm model and that the sorption results of Na-bentonite are better than those of *** behavior of both bentonites was strongly depending on pH,initial concentration and additional amounts of *** are three kinds of adsorption mechanism at different ranges of pH values:the competition adsorption between Cu2+ and H+(pH8.3).The removal rate of bentonite decreases with an increase in the initial metal ion *** maximum adsorption capacity of Na-bentonite was 26 mg/g and that of Ca-bentonite 12 mg/*** removal rate of Cu2+ was practically 100% at the initial concentration of 40 mg/L,when 4 g/L of Na-bentonite and 14 g/L of Ca-bentonite were added to the solution.

关键词： copper bentonite adsorption cation exchange waste water sorption isotherm

Construction and Resource Locating of Semantic P2P Grid Based on Description Logics

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Wuhan University Journal of Natural Sciences 2006年第1期11卷 78-82页

作者： SUN Xiao-lin LU Zheng-ding li yu-hua WEN Kun-mei li Rui-xuan College of Computer Science and Technology HuazhongUniversity of Science and Technology Wuhan 430074Hubei China

This paper proposes an algorithm applied in se mantic P2P network based on the description logics with the purpose for realizing the concepts distribution of resources, which makes the resources semantic locating easy. With the idea of the consistent hashing in the Chord, our algorithm stores the addresses and resources with the values of the same type to select instance. In addition, each peer has its own ontology, which will be completed by the knowledge distributed over the network during the exchange of CHGs （classification hierarchy graphs）. The hierarchy classification of concepts allows to find matching resource by querying to the upper level concept because the all concepts described in the CHG have the same root.

关键词： semantic P2P description logics consistent hashing ontology CHG (classification hierarchy graphs)

Research on the mechanism of the two-dimensional ultrasonic surface burnishing process to enhance the wear resistance for aluminum alloy

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Friction 2024年第3期12卷 490-509页

作者： Zhen-yu ZHOU Qiu-Yang ZHENG yu li Cong ding Guang-Jian PENG Zhong-yu PIAO College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310023China Key Laboratory of Special Purpose Equipment and Advanced Processing Technology Ministry of Education and Zhejiang ProvinceZhejiang University of TechnologyHangzhou 310014China

The gradient nanostructure is machined on the aluminum(Al)alloy by the two-dimensional ultrasonic surface burnishing process(2D-USBP).The mechanism of why the gradient nanostructure enhances wear resistance is *** mechanical properties and microstructure characterization for the gradient nanostructure are performed by operating a nanoindenter,transmission electron microscopy(TEM),and electron backscattered diffraction(EBSD).Dry wear tests are performed on the samples before and after machining to evaluate the wear resistance and *** effect of the gradient nanostructure on the wear resistance is explored by developing the crystal plasticity(CP)finite element and molecular dynamics(MD)*** characterization results show that the 2D-USBP sample prepared a gradient structure of~600μm thick on the aluminum surface,increasing the surface hardness from 1.13 to 1.71 GPa and reducing the elastic modulus from 78.84 to 70.14 *** optimization of the surface microstructure and the increase of the mechanical properties effectively enhance the wear resistance of the sample,with 41.20%,39.07%,and 54.58% of the wear scar areas for the 2D-USBP treated samples to the original samples under 5,10,and 15 N loads,*** gradient nanostructure hinders the slip of dislocations inside the sample during the wear process and reduces the size and scope of plastic deformation;meanwhile,the resistance to deformation,adhesion,and crack initiation and propagation of the sample surface is improved,resulting in enhanced wear resistance.

关键词： structural superlubricity lattice registry elastic deformation strained solitons crystal plasticity molecular dynamics simulations

Water modeling on fluid flow and mixing phenomena in a BOF steelmaking converter

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Journal of Iron and Steel Research International 2024年第3期31卷 595-607页

作者： Xin-yu Cai Hao-jian Duan ding-han li Anjun Xu li-feng Zhang School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing 100083China School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China

A 1∶8 physical water model was constructed to investigate the fluid flow and mixing phenomena in the basic oxygen furnace(BOF)*** particle image velocimetry was employed to measure the velocity distribution of the bath and the high-speed camera was applied to capture the cavity shape in the combined blowing BOF *** mixing time for varied operating conditions was measured by the stimulus-response *** cavity depth increased with the decrease in the lance height and the increase in the top gas flow rate while the bottom blowing gas had little influence on the cavity *** minimum cavity depth was obtained under the condition of a 69.8 m^(3)/h top gas flow rate,a 287.5 mm lance height and a 0.93 m^(3)/h bottom blowing gas flow rate,which was 161.2 *** mixing time decreased as the lance height decreased and the top blowing gas flow rate *** mixing time was first decreased and then increased with the increase in the bottom gas flow *** the condition of 69.8 m^(3)/h gas flow rate of top blowing,the 287.5 mm lance height and the 0.93 m^(3)/h gas flow rate of bottom blowing,the mixing time in the converter was 48.65 *** empirical formula between the stirring power and the mixing time in the converter was calculated.

关键词： Water model Fluid flow Particle image velocimetry Mixing time BOF converter