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VirtMan:design and implementation of a fast booting system for homogeneous virtual machines in iVCE

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Frontiers of Information Technology & Electronic Engineering 2016年第2期17卷 110-121页

作者： Zi-yang LI yi-ming ZHANG dong-sheng LI Peng-fei ZHANG Xi-cheng LU National Laboratory for Parallel and Distributed Processing School of ComputerNational University of Defense Technology

Internet-based virtual computing environment （iVCE） has been proposed to combine data centers and other kinds of computing resources on the Internet to provide efficient and economical services. Virtual machines （VMs） have been widely used in iVCE to isolate different users/jobs and ensure trustworthiness, but traditionally VMs require a long period of time for booting, which cannot meet the requirement of iVCE＇s large-scale and highly dynamic applications. To address this problem, in this paper we design and implement VirtMan, a fast booting system for a large number of virtual machines in iVCE. VirtMan uses the Linux Small Computer System Interface （SCSI） target to remotely mount to the source image in a scalable hierarchy, and leverages the homogeneity of a set of VMs to transfer only necessary image data at runtime. We have implemented VirtMan both as a standalone system and for OpenStack. In our 100-server testbed, VirtMan boots up 1000 VMs （with a 15 CB image of Windows Server 2008） on 100 physical servers in less than 120 s, which is three orders of magnitude lower than current public clouds.

关键词： Virtual machine Fast booting Homogeneity Internet-based virtual computing environment (iVCE)

D2ANet:Difference-aware attention network for multi-level change detection from satellite imagery

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Computational Visual Media 2023年第3期9卷 563-579页

作者： Jie Mei yi-Bo Zheng ming-ming Cheng TMCC CSNankai UniversityTianjin 300350China State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China

Recognizing dynamic variations on the ground,especially changes caused by various natural disasters,is critical for assessing the severity of the damage and directing the disaster ***,current workflows for disaster assessment usually require human analysts to observe and identify damaged buildings,which is labor-intensive and unsuitable for large-scale disaster *** this paper,we propose a difference-aware attention network(D2ANet)for simultaneous building localization and multi-level change detection from the dual-temporal satellite *** the differences in different channels in the features of pre-and post-disaster images,we develop a dual-temporal aggregation module using paired features to excite change-sensitive channels of the features and learn the global change *** the nature of building damage caused by disasters is diverse in complex environments,we design a difference-attention module to exploit local correlations among the multi-level changes,which improves the ability to identify damage on different *** experiments on the large-scale building damage assessment dataset xBD demonstrate that our approach provides new state-of-the-art *** code is publicly available at https://***/mj129/D2ANet.

关键词： change detection building localization sate-llite imagery dual-temporal aggregation difference attention

A Class of Finite-Dimensional Representations of U_q(sl_2)

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维普期刊数据库

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Acta Mathematica Sinica,English Series 2013年第9期29卷 1703-1712页

作者： dong ming CHENG dong SU Department of Mathematics and Applied Mathematics He'nan University of Science and Technology

In order to study a class of finite-dimensional representations of Uq（sl2）, we deal with the quotient algebra Uq （m, n, b） of quantum group Uq（sl2） with relations Kr=1, Emr=b, Fnr=0 in this paper, where q is a root of unity. The algebra Uq（m, n, b） is decomposed into a direct sum of indecomposable （left） ideals. The structures of indecomposable projective representations and their blocks are determined.

关键词： Quantum group representation root of unity

Modeling and simulation of pinhole channels

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The Journal of China Universities of Posts and Telecommunications 2010年第2期17卷 67-71页

作者： WEI ming-dong ZHANG Yun-feng ZHANG Ye-rong PAN Zi-yi School of Eleca:onic Science and Engineering Nanjing University of Posts and Teleenmmtmications Nanjing 210003 China Jiangsu Posts and Telecommunications Planning and Designing Institute Co. Ltd Nanjing 210006 China

This article presents a general pinhole channel reference model based on the cause of pinhole effect. On the base of this reference model, a deterministic simulation model is developed by keeping the difference of correlation properties between reference and simulation model as smaller as possible. The correlation properties include temporal autocorrelation fimction （ACF）, two-dimensional （2-D） space cross-correlation function （CCF） and frequency correlation function （FCF）. The results show that although pinhole channel has good correlation properties, the channel capacity is very low because of the low rank of channel transform matrix.

关键词： pinhole channel modeling channel simulation deterministic simulation models

A Self-Healing Elastomer with Extremely High Toughness Achieved by Acylsemicarbazide Hydrogen Bonding and Cu^(2+)-Neocuproine Coordination Interactions

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Chinese Journal of Polymer Science 2024年第10期42卷 1425-1434,I0007页

作者： Xiao-ming An yi-Ping Wang Tang-Song Zhu Chong Xing Xu-dong Jia Qiu-Hong Zhang Key Laboratory of High Performance Polymer Material and Technology of MOE Department of Polymer Science and EngineeringSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing210093China State Key Laboratory of Coordination Chemistry Nanjing UniversityNanjing210093China

Elastomers with high mechanical toughness can guarantee their durability during service ***-healing ability,as well as recyclability,can also extend the life of materials and save the consuming cost of the *** efforts have been dedicated to promoting the mechanical toughness as well as the self-healing capability of elastomers at the same time,while it remains a challenge to balance the trade-off between the above properties in one *** we proposed a molecular design driven by dual interactions of acylsemicarbazide hydrogen bonding and Cu^(2+)-neocuproine coordination *** introducing the reversible multiple hydrogen bonds and strong coordination bonds,we successfully fabricated an extremely tough and self-healing *** elastomer can achieve an impressive top-notch toughness of 491 MJ/m^(3).Furthermore,it boasted rapid elastic restorability within 10 min and outstanding crack tolerance with high fracture energy(152.6kJ/m^(2)).Benefiting from the combination of dynamic interactions,the material was able to self-repair under 80℃conveniently and could be reprocessed to restore the exceptional mechanical properties.

关键词： Metal-ligand coordination Hydrogen bond Ultra-tough elastomer Self-healing

Boundary-layer disturbances subjected to free-stream turbulence and simulation on bypass transition

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Applied Mathematics and Mechanics(English Edition) 2016年第8期37卷 967-986页

作者： Hong QIN ming dong Department of Mechanics Tianjin University Tianjin 300072 China Tianjin Key Laboratory of Modern Engineering Mechanics Tianjin 300072 China

The phenomena associated with the entrainment of free-stream turbulence （FST） into boundary-layer flows are relevant for a number of subjects. It has been be- lieved that the continuous spectra of the Orr-Sommerfeld （O-S）/Squire equations describe the entrainment process, and thus they are used to specify the inlet condition in simulation of bypass transition. However, dong and Wu （dong, M. and Wu, X. On continuous spectra of the Orr-Sommerfeld/Squire equations and entrainment of free-stream vortical disturbances. Journal of Fluid Mechanics, 732, 616-659 （2013）） pointed out that continuous spectra exhibit several non-physical features due to neglecting the non-parallelism. They further proposed a large-Reynolds-number asymptotic approach, and showed that the non-parallelism is a leading-order effect even for the short-wavelength disturbance, for which the response concentrates in the edge layer. In this paper, the asymptotic solution is verified numerically by studying its evolution in incompressible boundary layers. It is found that the numerical results can be accurately predicted by the asymptotic solution, implying that the latter is adequate for moderate Reynolds numbers. By introducing a series of such solutions as the inflow perturbations, the bypass transition is investigated via the direct numerical simulation （DNS）. The transition processes, including the evolution of streaks, the amplification of secondary-instability modes, and the emergence of turbulent spots, agree with the experimental observations.

关键词： free-stream turbulence (FST) bypass transition boundary layer asymptotic direct numerical simulation (DNS)

Visual-attention gabor filter based online multi-armored target tracking

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Defence Technology（防务技术） 2021年第4期17卷 1249-1261页

作者： Fan-jie Meng Xin-qing Wang Fa-ming Shao dong Wang Yao-wei Yu yi Xiao Department of Mechanical Engineering College of Field EngineeringArmy Engineering University of PLANanjing 210007China College of Civil Aviation Nanjing University of Aeronautics and AstronauticsNanjing 210007China

The multi-armored target tracking(MATT)plays a crucial role in coordinated tracking and *** occlusion and insertion among targets and target scale variation is the key problems in *** stateof-the-art multi-object tracking(MOT)works adopt the tracking-by-detection strategy,which rely on compute-intensive sliding window or anchoring scheme in detection module and neglect the target scale variation in tracking *** this work,we proposed a more efficient and effective spatial-temporal attention scheme to track multi-armored target in the ground *** simulating the structure of the retina,a novel visual-attention Gabor filter branch is proposed to enhance *** introducing temporal information,some online learned target-specific Convolutional Neural Networks(CNNs)are adopted to address *** importantly,we built a MOT dataset for armored targets,called Armored Target Tracking dataset(ATTD),based on which several comparable experiments with state-ofthe-art methods are *** results show that the proposed method achieves outstanding tracking performance and meets the actual application requirements.

关键词： Multi-object tracking Deep learning Gabor filter Biological vision Military Application Video processing

Unfused-ring Acceptors with Dithienobenzotriazole Core for Efficient Organic Solar Cells

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Chinese Journal of Polymer Science 2022年第12期40卷 1586-1593,I0007页

作者： Zui-yi Zhong Jia-Xin Xu Kai Zhang ming-Hao dong Qi-Ri Huang Fei Huang Institute of Polymer Optoelectronic Materials and Devices State Key Laboratory of Luminescent Materials and DevicesSouth China University of TechnologyGuangzhou 510640China

In recent years, non-fullerene acceptors(NFAs) with unfused-ring structure have received extensive attention due to their flexible combination of building blocks and relatively simple synthetic routes. In this work, three new A-D-C-D-A type unfused-ring acceptors(UFAs),named DTBTz EH-IC2F, DTBTz Me-IC2F and DTBTz Me-IC2Cl, were designed and synthesized with dithienobenzotriazole(DTBTz) as the *** modification of alkyl chain on the DTBTz unit and change of halogen atoms on the cyanoindanone end groups, the differences in optoelectronic properties of these three small molecule acceptors were investigated. The results show that changes in alkyl chain and halogen atom endow UFAs with different features, including shift in absorption, changes in energy level and molecular packing. When blended with donor PBDB-T, the organic solar cell based on DTBTz Me-IC2Cl achieves the highest device efficiency of 12.3%, while DTBTz EH-IC2F-based device obtains 11.5% efficiency and DTBTz Me-IC2F-based device obtains 12.0% efficiency. The stability tests show that all the devices obtain good efficiency retention rates. These results demonstrate that the introduction of a rigid aromatic ring DTBTz as an intermediate core not only effectively results in highly planar A-D-C-D-A small molecules, but also provides a new reference for the design and development of UFAs in OSCs.

关键词： Organic solar cells Non-fullerene acceptors Unfused-ring

Mechanisms Causing Ballistic Thermal Rectification

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Chinese Physics Letters 2014年第4期31卷 118-121页

作者： DING Xing ming yi School of Physics and Material Science Anhui University Hefei 230601

The mechanism causing the ballistic thermal rectification in the harmonic system is analytically studied. Using the conceptual model of a dephasing probe, we obtain that phase breaking is unnecessary to realize the ballistic thermal rectification. However, it can change the strength of rectification. Asymmetric phonon-phonon interac- tion inducing the energy exchange of the normal mode of vibration is necessary to realize the ballistic thermal rectification. Moreover, the quantum statistics of phonons in at least one thermal reservoir is crucial to guarantee the asymmetric phonon-phonon interaction.

关键词： Rectification Mechanisms ballistic