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science in china(Series F) 2009年第5期52卷 813-823页

作者： zheng weimin FANG BinXing department of computer science and {3. Tsinghua University Beijing 100084 China beijing university of Posts and Telecommunications Beijing 100876 China

Disaster recovery （DR） techniques ensure the data safety and service continuity under different natural and human-made disasters by constructing a high reliable storage system. Traditional disaster recovery methods are structure-dependent. It is hard to share the DR resources between different DR systems, which made it expensive. We present a structure-independent disaster recovery theory and its implementation methods in this paper. By backup the whole system but not just the data, the goal of device and application-independent disaster recovery has been achieved. We further present a parallel recovery model and an on demand data retrieval method based on the theory. Some implementation details of prototype recovery system are also discussed. With the methods independent from specific devices or applications, the cost of disaster recovery infrastructure can be essentially reduced by resource sharing. Experiments show that the recovery time has also been greatly shortened with little service degradation.

关键词： disaster recovery parallel virtualization

Low friction of superslippery and superlubricity:A review

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Friction 2023年第7期11卷 1121-1137页

作者： Zijian zheng Zhiguang GUO weimin LIU Jianbin LUO Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials Hubei UniversityWuhan 430062China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China

The issues regarding energy dissipation and component damage caused by the interface friction between a friction pair attract enormous attention to friction *** key-enabling technique to realize friction reduction is the use of *** lubricants smooth the contact interfaces,achieving an ultralow friction contact,which is called superslippery or *** present,superslippery and superlubricity are two isolated research *** is a lack of unified definition on superslippery and superlubricity from the viewpoint of ***,this review aims at exploring the differences and relations between superslippery and superlubricity from their origin and application ***,the challenges for developing superslippery surface and superlubricity surface are *** addition,perspectives on the interactive development of these two surfaces are *** hope that our discussion can provide guidance for designing superslippery or superlubricity surfaces by using varies drag-reduction technologies.

关键词： low friction superslippery superlubricity tribology lubricants

Effect of pouring temperature on semi-solid slurry of ZL101 alloy prepared by slightly electromagnetic stirring

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china Foundry 2009年第1期6卷 9-14页

作者： Liu zheng Mao weimin Faculty of Material and Chemical Engineering Jiangxi University of Science and Technology Ganzhou 341000 China School of Material science and Engineering University of Science ＆ Technology Beijing Beijing 100083 China

The semi-solid slurry of ZL101 alloy is prepared by a combination technology of low superheat pouring and slightly electromagnetic stirring. The effects of pouring temperature on the slurry prepared by the technology are investigated. The results indicate that it is feasible to prepare the slurry with globular primary phases by low superheat pouring and slightly electromagnetic stirring, and that the pouring temperature has an important effect on the morphology and the size of primary α-AI in ZL101 alloy. By applying suitable slightly electromagnetic stirring combining with relatively increased pouring temperature, i.e., in a practical way to apply low superheat pouring technology, is capable of obtaining appropriate semi-solid slurry of ZL101 alloy with globular shape of primary phase. Compared with the samples made by low superheat pouring only without stirring, the samples prepared by applying both slightly electromagnetic stirring and low superheat pouring can enable to achieve the same grain size and morphology of the primary phase with that of pouring at 15-3.℃ higher.

关键词： semi-solid slurry pouring temperature slightly electromagnetic stirring ZL101 alloy

Towards optimized tensor code generation for deep learning on sunway many-core processor

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Frontiers of computer science 2024年第2期18卷 1-15页

作者： Mingzhen LI Changxi LIU Jianjin LIAO Xuegui zheng Hailong YANG Rujun SUN Jun XU Lin GAN Guangwen YANG Zhongzhi LUAN Depei QIAN State Key Laboratory of Software Development Environment Beijing 100191China School of computer science and Engineering Beihang UniversityBeijing 100191China National university of Singapore Singapore 119077Singapore State Key Laboratory of Mathematical Engineering and Advanced Computing Wuxi 214000China science and technology on Special System Simulation Laboratory beijing Simulation Center Beijing 100854China department of computer science and {3. Tsinghua UniversityBeijing 100084China

The flourish of deep learning frameworks and hardware platforms has been demanding an efficient compiler that can shield the diversity in both software and hardware in order to provide application *** the existing deep learning compilers,TVM is well known for its efficiency in code generation and optimization across diverse hardware *** the meanwhile,the Sunway many-core processor renders itself as a competitive candidate for its attractive computational power in both scientific computing and deep learning *** paper combines the trends in these two ***,we propose swTVM that extends the original TVM to support ahead-of-time compilation for architecture requiring cross-compilation such as *** addition,we leverage the architecture features during the compilation such as core group for massive parallelism,DMA for high bandwidth memory transfer and local device memory for data locality,in order to generate efficient codes for deep learning workloads on *** experiment results show that the codes generated by swTVM achieve 1.79x improvement of inference latency on average compared to the state-of-the-art deep learning framework on Sunway,across eight representative *** work is the first attempt from the compiler perspective to bridge the gap of deep learning and Sunway processor particularly with productivity and efficiency in *** believe this work will encourage more people to embrace the power of deep learning and Sunwaymany-coreprocessor.

关键词： sunway processor deep learning compiler code generation performance optimization

Hardware Implementation of Spiking Neural Networks on FPGA

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tsinghua science and technology 2020年第4期25卷 479-486页

作者： Jianhui Han Zhaolin Li weimin zheng Youhui Zhang the Institute of Microelectronics Tsinghua UniversityBeijing 100084China the Research Institute of Information technology Tsinghua UniversityBeijing 100084China the department of computer science and {3. Tsinghua UniversityBeijing 100084China

Inspired by real biological neural models,Spiking Neural Networks(SNNs)process information with discrete spikes and show great potential for building low-power neural network *** paper proposes a hardware implementation of SNN based on Field-Programmable Gate Arrays(FPGA).It features a hybrid updating algorithm,which combines the advantages of existing algorithms to simplify hardware design and improve *** proposed design supports up to 163.4 neurons and 16.8 million synapses but requires minimal hardware resources and archieves a very low power consumption of 0.477 W.A test platform is built based on the proposed design using a Xilinx FPGA evaluation board,upon which we deploy a classification task on the MNIST *** evaluation results show an accuracy of 97.06%and a frame rate of 161 frames per second.

关键词： Spiking Neural Network(SNN) Field-Programmable Gate Arrays(FPGA) digital circuit low-power MNIST

Oxygen‑Coordinated Single Mn Sites for Efficient Electrocatalytic Nitrate Reduction to Ammonia

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Nano-Micro Letters 2024年第1期16卷 147-159页

作者： Shengbo Zhang Yuankang Zha Yixing Ye Ke Li Yue Lin Lirong zheng Guozhong Wang Yunxia Zhang Huajie Yin Tongfei Shi Haimin Zhang Laboratory of Materials Physics Centre for Environmental and Energy NanomaterialsAnhui Key Laboratory of Nanomaterials and NanotechnologyCAS Center for Excellence in NanoscienceInstitute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031People’s Republic of China university of science and technology of{3. Hefei 230026People’s Republic of China Key Laboratory of Agricultural Sensors Ministry of AgricultureSchool of Information and ComputerAnhui Agricultural UniversityHefei 230026People’s Republic of China Hefei National Research Center for Physical sciences at the Microscale University of Science and Technology of ChinaHefei 230026People’s Republic of China beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of Sciences19B Yuquan RoadBeijing 100049People’s Republic of China

Electrocatalytic nitrate reduction reaction has attracted increasing attention due to its goal of low carbon emission and environmental ***,we report an efficient NitRR catalyst composed of single Mn sites with atomically dispersed oxygen(O)coordination on bacterial cellulose-converted graphitic carbon(Mn-O-C).Evidence of the atomically dispersed Mn-(O-C_(2))_(4)moieties embedding in the exposed basal plane of carbon surface is confirmed by X-ray absorption *** a result,the as-synthesized Mn-O-C catalyst exhibits superior NitRR activity with an NH_(3.yield rate(RNH_(3.)of 1476.9±62.6μg h^(−1)cm^(−2)at−0.7 V(*** hydrogen electrode,RHE)and a faradaic efficiency(FE)of 89.0±3.8%at−0.5 V(***)under ambient ***,when evaluated with a practical flow cell,Mn-O-C shows a high RNH_(3.of 3.06.7±552.0μg h^(−1)cm^(−2)at a current density of 100 mA cm−2,2.5 times of that in the H *** in situ FT-IR and Raman spectroscopic studies combined with theoretical calculations indicate that the Mn-(O-C_(2))_(4)sites not only effectively inhibit the competitive hydrogen evolution reaction,but also greatly promote the adsorption and activation of nitrate(NO_(3.^(−)),thus boosting both the FE and selectivity of NH_(3.over Mn-(O-C_(2))_(4)sites.

关键词： Atomically dispersed Oxygen coordination Nitrate reduction reaction In situ spectroscopic studies Hydrogen evolution reaction

Influence of deposition time of TiN layer on the tribological properties of the Ti-TiN-TiCN coatings deposited by DCMS

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Influence of deposition time of TiN layer on the tribologica...

Study and Realization of Internet-assisted Bidding System for Construction Project

china 6th International Symposium on Tribology

作者： Jianyun zheng~(1 2) Junying Hao~1 Xiaoqiang Liu~(1 2) weimin Liu~1 1:State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of sciences Lanzhou 73.000 P.R.{3. 2:Graduate university of Chinese Academy of science beijing 100049 P.R.{3.

＜正＞*** For about three decades,titanium carbonitride（TiCN） coatings attract great attention due to their combined high hardness,high toughness,low friction coefficient, excellent wear and abrasion resistance[1-4].Generally, when preparing the TiCN coatings,many people most pay attention to deposition method,deposition parameters like gas composition and temperature,and doping of other elements[1,4,5-8].In this study,the Ti-TiN-TiCN coatings were synthesized by DCMS

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Study and Realization of Internet-assisted Bidding System fo...

Employing intelligence in object-based storage devices to provide attribute-based file access

2009中国控制与决策会议

作者： Lun Xie,Lili Bian,zheng Yang,Zhiliang Wang university of science and {3. beijing,Xueyuan road No.3.,beijing 100083.china

＜正＞This paper adopts XML technology to establish standard development of electronic tender,which format is not unified in traditional construction project internet-assisted bidding *** view the lack of scientific evaluation of the decision-making model,the two-level system of fuzzy evaluation model based on single-weight system evaluation model is put forward for both experts and bidders so as to realize qualitative and quantitative *** on the above work,an internet-assisted bidding system for construction project is developed by the supporting techniques such as C#,XML and *** three-layer architecture of this system is constructed and its working flow is *** performance shows the feasibility and effectiveness of this system and provides important reference for the computer aided bid evaluation system.

关键词： XML Hierarchy Fuzzy Evaluation Model Internet-assisted Bidding System Construction Project

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science china(Information sciences) 2013年第3期56卷 169-178页

作者： ZHANG YouHui QIAN ZiQiang zheng weimin department of computer science and {3. Tsinghua University

Attribute-based file access has been regarded as a promising method to reach files based on their attributes rather than through the usual directory hierarchy,which is especially meaningful for locating the target among mass of ***,because the attribute-based file system introduces higher performance overhead and is usually incompatible with existing file access interfaces,till now there are few practical attribute-based file *** paper designs a file system with attribute-based access methods and a compatible access interface,using object-based storage devices(OSD).In detail,this design fully utilizes existing features of the OSD standard(T10):object attributes and access methods are mapped into file attributes and the corresponding access interfaces respectively;collection-objects are used for fast indexing of user ***,the attribute-based object organization can be achieved in OSD efficiently and the powerful processing capability of OSD is used to complete object-queries to speed up the ***,the way to export the new accessing methods through file system with a compatible interface is also *** a prototype has been *** show that it introduces much less overheads than some existing attribute-based file systems,and the query performance is higher than its counterpart based on the block-level device.

关键词： attribute-based file access object-based storage device intelligent storage