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Journal of Wuhan University of technology(Materials Science) 2019年第4期34卷 845-850页

作者： SUN Weitao ZHOU Wenlong College of Mechatronics Engineering Binzhou UniversityBinzhou 256600China School of Materials Science and Engineering Dalian University of TechnologyDalian 116085China

A fixed-point observation method was designed to research the dynamic tribological performance of one certain resin-based friction materials. The friction test was performed through a constant speed friction tester under various temperature conditions. It was found that the dynamic tribological performance of materials has a good consistency with the dynamic evolution of worn surfaces. At lower temperatures, the friction coefficient and wear rate were constant, resulted from the stable worn surfaces. At higher temperatures, the friction coefficient increased gradually, while the wear rate decreased, due to the increasing contact area and Fe concentration. A fade occurred above 250 ℃, which can be explained by the degradation of binders.

关键词： resin-based friction materials dynamic tribological performance worn surfaces

Task mapper and application-aware virtual machine scheduler oriented for parallel computing

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第3期13卷 155-177页

作者： Jing ZHANG Xiao-jun CHEN Jun-huai LI Xiang LI School of Computer Science and Engmeering Xi'an University of TechnologyXi'an 710048China State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong UniversityXi'an 710048China

We design a task mapper TPCM for assigning tasks to virtual machines, and an application-aware virtual machine scheduler TPCS oriented for parallel computing to achieve a high performance in virtual computing systems. To solve the problem of mapping tasks to virtual machines, a virtual machine mapping algorithm (VMMA) in TPCM is presented to achieve load balance in a cluster. Based on such mapping results, TPCS is constructed including three components: a middleware supporting an application-driven scheduling, a device driver in the guest OS kernel, and a virtual machine scheduling algorithm. These components are implemented in the user space, guest OS, and the CPU virtualization subsystem of the Xen hypervisor, respectively. In TPCS, the progress statuses of tasks are transmitted to the underlying kernel from the user space, thus enabling virtual machine scheduling policy to schedule based on the progress of tasks. This policy aims to exchange completion time of tasks for resource utilization. Experimental results show that TPCM can mine the parallelism among tasks to implement the mapping from tasks to virtual machines based on the relations among subtasks. The TPCS scheduler can complete the tasks in a shorter time than can Credit and other schedulers, because it uses task progress to ensure that the tasks in virtual machines complete simultaneously, thereby reducing the time spent in pending, synchronization, communication, and switching. Therefore, parallel tasks can collaborate with each other to achieve higher resource utilization and lower overheads. We conclude that the TPCS scheduler can overcome the shortcomings of present algorithms in perceiving the progress of tasks, making it better than schedulers currently used in parallel computing.

关键词： Virtual machine Virtualization Application-aware Parallel computing Virtual machine mapping Credit algorithm Virtual machine scheduling

Mapping wetland changes in China between 1978 and 2008

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Chinese Science Bulletin 2012年第22期57卷 2813-2823页

作者： NIU ZhenGuo ZHANG HaiYing WANG XianWei YAO WenBo ZHOU deMin ZHAO KuiYi ZHAO Hui LI NaNa HUANG HuaBing LI CongCong YANG Jun LIU CaiXia LIU Shuang WANG Lin LI Zhan YANG ZhenZhong QIAO Fei ZHENG YaoMin CHEN YanLei SHENG YongWei GAO XiaoHong ZHU WeiHong WANG WenQing WANG Hong WENG YongLing ZHUANG daFang LIU JiYuan LUO ZhiCai CHENG Xiao GUO ZiQi GONG Peng State Key Laboratory of remote Sensing Science Jointly Sponsored by Institute of Remote Sensing ApplicationsChinese Academy of Sciences and Beijing Normal UniversityBeijing 100101China Ministry of Education Key Laboratory for Earth System Modeling Center for Earth System ScienceInstitute for Global Change StudiesTsinghua UniversityBeijing 100084China department of resource Environment and Tourism Capital Normal UniversityBeijing 100037China Northeast Institute of Geography and Agricultural Ecology Chinese Academy of SciencesChangchun 130012China department of Geography and remote Sensing Beijing Normal UniversityBeijing 100875China College of Forestry Beijing Forestry UniversityBeijing 100083China department of Environmental Science Policy and ManagementUniversity of CaliforniaBerkeley94720USA department of Geography University of CaliforniaLos Angeles90095USA department of Life and Geographic Sciences Qinghai Normal UniversityXining 810008China department of Geography Yanbian UniversityYanbian 133002China School of Environment and Ecology Xiamen UniversityXiamen 361005China School of Geographical Information Science Hohai UniversityNanjing 211100China School of Surveying and Mapping Transportation Engineering Southeast UniversityNanjing 210096China Institute of Geographical Sciences and Natural resources research Chinese Academy of SciencesBeijing 100101China School of Surveying and Mapping Wuhan UniversityWuhan 430079China

Four wetland maps for all China have been produced,based on Landsat and CBErS-02B remote sensing data between 1978 and 2008 (1978,1990,2000 and 2008).These maps were mainly developed by manual interpretation and validated by substantial field investigation in *** on these maps,we analyzed the 2008 wetland distribution in China and discussed wetland changes and their drivers over the past 30 years.(i) There were about 324097 km 2 of wetlands in 2008,for which inland marshes or swamps were the most common wetland type (35%),with lakes (26%) *** of the wetlands were in Heilongjiang,Inner Mongolia,Qinghai and Tibet,occupying about 55% of the national wetland area.(ii) From 1978 to 2008,China's wetland area continually and significantly decreased,by about 33% based on changes in the wetland *** was in sharp contrast to the increase in artificial wetlands,which increased by about 122%.Inland marshes accounted for the main loss of total wetlands from 1978 to *** 2000 through 2008,riverine and lacustrine wetlands constituted the main wetland *** however,the rate of wetland loss decreased from 5523 to 831 km 2 /a.(iii) The change ratio of lost natural wetlands (including inland and coastal wetlands) to non-wetlands has decreased slightly over the past 30 *** 1978 to 1990,nearly all natural wetlands (98%) lost were transformed into ***,the ratio declined to 86% from 1990 to 2000,and to 77% from 2000 to 2008.(iv) All Chinese provinces were divided into three groups according to patterns of wetland changes,which could relate to the driving forces of such *** was completely different from other provinces,as it was one representative example in which there was a net wetland increase,because of global warming and decreased human activity since *** economic development caused considerable wetland loss in most eastern provinces,and artificial wetlands increased.

关键词：湿地变化中国地图映射地球资源卫星内陆湿地人工湿地全球气候变暖湿地面积

Modeling of a dynamic dual-input dual-output fast steering mirror system

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Frontiers of Information technology & Electronic Engineering 2017年第10期18卷 1488-1498页

作者： Hong SONG Jia-heng ZHANG Ping YANG Hao-cai HUANG Shu-yue ZHAN Teng-jun LIU Yi-lu GUO Hang-zhou WANG Hui HUANG Quan-quan MU Mei-fen FANG Ming-yuan YANG Ocean College Zhejiang UniversityZhoushan 316021China School of digital Media&design Hangzhou Dianzi UniversityHangzhou 310018China State Key Laboratory of Applied Optics Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesJilin 130033China Blue-Science Opto-Electronics Co.Ltd. Hangzhou 310018China Core Tomorrow Science&technology Co.Ltd. Harbin 150080China

A modeling method is proposed for a dynamic fast steering mirror(FSM) system with dual inputs and dual outputs. A physical model of the FSM system is derived based on first principles, describing the dynamics and coupling between the inputs and outputs of the FSM system. The physical model is then represented in a state-space form. Unknown parameters in the state-space model are identified by the subspace identification algorithm, based on the measured input-output data of the FSM system. The accuracy of the state-space model is evaluated by comparing the model estimates with measurements. The variance-accounted-for value of the state-space model is better than 97%, not only for the modeling data but also for the validation data set, indicating high accuracy of the model. Comparison is also made between the proposed dynamic model and the conventional static model, where improvement in model accuracy is clearly observed. The model identified by the proposed method can be used for optimal controller design for closed-loop FSM systems. The modeling method is also applicable to FSM systems with similar structures.

关键词： Fast steering mirror dynamic system Input-output coupling,Physical modeling Subspace identification

Online measurement of solids motion in fluidized bed reactor with different distributor for Fischer–Tropsch synthesis

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Chinese Journal of Chemical Engineering 2018年第10期26卷 2003-2008页

作者： Xiaolai Zhang Weixin Qian Haitao Zhang Qiwen Sun Weiyong Ying Engineering research Centre of Large Scale reactor Engineering and technology Ministry of Education State Key Laboratory of Chemical Engineering East China University of Science and Technology Shanghai 200237 China State Key Laboratory of Coal Liquefaction and Coal Chemical technology Shanghai 201203 China

In this paper, the distributions of particle velocity in a gas–solid fluidized bed with branched pipe distributor or circle distributor were measured by using a laser doppler velocimetry. Our results show that, within a certain range of superficial gas velocity, when using circle distributor, the particle velocity is large and the distribution of the particle velocity is even more compared with the branched pipe distributor. On the basis of the amplitude of tangential movement statistics, the amplitude of tangential movement statistics(AVATMS) decreases with increasing the axial height under the appropriate superficial gas velocity.

关键词： Fischer–Tropsch synthesis Laser doppler velocimetry Fluidized bed

A New Vector data Compression Approach for WebGIS

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Geo-Spatial Information Science 2011年第1期14卷 48-53页

作者： LIYunjin ZHONG Ershun Institute of Geographic Sciences and Natural resources research. Chinese Academy of Sciences llA Datun Road Chaoyang District Beijing 100101 China

high compression ratio,high decoding performance,and progressive data transmission are the most important require-ments of vector data compression algorithms for *** meet these requirements,we present a new compression *** paper begins with the generation of multiscale data by converting float coordinates to integer *** is proved that the distance between the converted point and the original point on screen is within 2 pixels,and therefore,our approach is suitable for the visualization of vector data on the client *** coordinates are passed to an Integer Wavelet Transformer,and the high-frequency coefficients produced by the transformer are encoded by Canonical Huffman *** experimental results on river data and road data demonstrate the effectiveness of the proposed approach:compression ratio can reach 10% for river data and 20% for road data,*** conclude that more attention needs be paid to correlation between curves that contain a few points.

关键词： vector data compression WebGIS progressive data transmission

Co-expression Analysis Identifies CrC and AP1 the regulator of Arabidopsis Fatty Acid Biosynthesis

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Journal of Integrative Plant Biology 2012年第7期54卷 486-499页

作者： Xinxin Han Linlin Yin Hongwei Xue national Key Laboratory of Plant Molecular Genetics Institute of Plant Physiology and EcologyShanghai Institutes for Biological SciencesChinese Academy of Sciences20032 ShanghaiChina

Fatty acids （FAs） play crucial rules in signal transduction and plant development, however, the regulation of FA metabolism is still poorly understood. To study the relevant regulatory network, fifty-eight FA biosynthesis genes including de novo synthases, desaturases and elongases were selected as ＂guide genes＂ to construct the co-expression network. Calculation of the correlation between all Arabidopsis thaliana （L.） genes with each guide gene by Arabidopsis co-expression dating mining tools （ACT） identifies 797 candidate FA-correlated genes. Gene ontology （GO） analysis of these co-expressed genes showed they are tightly correlated to photosynthesis and carbohydrate metabolism, and function in many processes. Interestingly, 63 transcription factors （TFs） were identified as candidate FA biosynthesis regulators and 8 TF families are enriched. Two TF genes, CrC and AP1, both correlating with 8 FA guide genes, were further characterized. Analyses of the ap1 and crc mutant showed the altered total FA composition of mature seeds. The contents of palmitoleic acid, stearic acid, arachidic acid and eicosadienoic acid are decreased, whereas that of oleic acid is increased in apl and crc seeds, which is consistent with the qrT-PCr analysis revealing the suppressed expression of the corresponding guide genes. In addition, yeast one-hybrid analysis and electrophoretic mobility shift assay （EMSA） revealed that CrC can bind to the promoter regions of KCS7 and KCS15, indicating that CrC may directly regulate FA biosynthesis.

关键词： Fatty acid Arabidopsis AP1 CrC co-expression analysis.

relationship between crystal growth mode, preferred orientation and magnetostriction of (Tb_(0.3)dy_(0.7))Fe_(1.95) alloys

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Journal of rare Earths 2008年第3期26卷 388-391页

作者：张世荣李扩社于敦波李勇胜杨红川李红卫涂赣峰 School of Materials and Metallurgy Northeastern University national Engineering research Center for rare Earth Materials General Research Institute for Non-Ferrous Metals Grirem Advanced Materials Co. Ltd. Beijing 100088 China national Engineering research Center for rare Earth Materials General Research Institute for Non-Ferrous Metals Grirem Advanced Materials Co. Ltd.

The relationship between crystal growth mode, preferred orientation and magnetostrictive properties of （Tb0.3dy0.7）Fe1.95 alloys was investigated at different directional solidification rates. The results showed that preferred orientation had a strong influence on the characteristics of （Tb0.3dy0.7）Fe1.95 alloys. At lower solidification rates, the sample with 〈110〉 preferred orientation showed larger low-field magnetostriction and apparent compressive stress effect. The excessive solidification rate resulted in failure of preferred orientation and a poor magnetostrictive performance. With an increase in solidification rates, the crystal growth modes changed gradually from cellular and primary dendrite morphology to developed dendritic morphology. In addition, domain configurations were observed using magnetic force microscopy, and the change of magnetostrictive properties was interpreted in terms of revealing the domain configurations.

关键词： preferred orientation TbdyFe magnetostriction magnetic domain structure rare earths

LdV measurements of particle velocity distribution in an annular stripper

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Chinese Journal of Chemical Engineering 2019年第10期27卷 2293-2303页

作者： Yongzheng Li Xiaolai Zhang Guangwei Zhai Haitao Zhang Tao Li Qiwen Sun Weiyong Ying Engineering research Center of Large Scale reactor Engineering and technology Ministry of EducationState Key Laboratory of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China School of Chemistry and Chemical Engineering Shandong UniversityJinan 250100China State Key Laboratory of Coal Liquefaction and Coal Chemical technology Shanghai 201203China

Particle descent velocities in an annular stripper were measured by a laser doppler velocimetry(LdV)*** the radial direction,particle descent velocity was relatively constant in the mid-region of the stripper and increased towards the walls on both sides,exhibiting an anti-U-shaped *** descent velocity in the radial mid-region increased with the increase of superficial gas velocity,and the maximum in the outer wall region increased significantly with the increase of solid mass *** stripping gas velocity had stronger effect on particle velocity distributions near the stripper gas distributor,and such effect weakened with the increase of the distance from the *** particle velocity and its radial profiles could be adjusted by changing the superficial stripping gas *** formulas were established to describe the relationships between the local particle velocity and cross-sectional averaged velocity based on the effects of operating conditions and measuring *** result showed that the predicted data was in good agreement with the experimental value.

关键词： Annular stripper Flow Hydrodynamics Particle velocity Laser doppler velocimeter

Linearity analysis of closed-loop capacitive accelerometer due to distance mismatch between plates and the influence of compensation capacitor array

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Science China(Information Sciences) 2014年第6期57卷 199-210页

作者： HUANG JingQing ZHAO Meng ZHANG TingTing CHEN ZhongJian HONG LiChen WU Feng ZHANG YaCong LU WenGao GAO ChengChen HAO YiLong national Key Laboratory of Science and technology on Micro/Nano Fabrication Institute of MicroelectronicsPeking University

This paper presents mathematical formulae showing that the distance mismatch for an uncentered proof mass in an accelerator sensor does not influence the linearity of the closed-loop accelerometer as a *** asymmetry in sensors only introduces an output voltage offset in the readout integrated *** simulation using Matlab/Simulink confirms the mathematical *** linear response after compensation with a conventional capacitor array is also simulated and *** show that there is a loss in *** results hold not only for the continuous-time architecture,but also for a time-divided architecture.A readout integrated circuit with a time-divided architecture is designed and fabricated using a 0.35μm HV CMOS *** accelerometer composed of a microelectromechanical system sensor with severe built-in distance mismatch and the designed readout integrated circuit is *** results show that the nonlinearity of such accelerometer is within 0.3%.

关键词： linearity closed-loop accelerometer capacitive MEMS rOIC