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A Lightweight Three-Factor User Authentication Protocol for the Information Perception of IoT

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Computers, Materials & Continua 2019年第2期58卷 545-565页

作者： liang kou Yiqi Shi Liguo Zhang Duo Liu Qing Yang College of Computer Science and Technology Harbin Engineering UniversityHarbin150001China 2Harbin University of Commerce Harbin150001China 3University of North Texas Denton76207USA

With the development of computer hardware technology and network technology,the Internet of Things as the extension and expansion of traditional computing network has played an increasingly important role in all professions and trades and has had a tremendous impact on people *** information perception of the Internet of Things plays a key role as a link between the computer world and the real ***,there are potential security threats in the Perceptual Layer Network applied for information perception because Perceptual Layer Network consists of a large number of sensor nodes with weak computing power,limited power supply,and open communication *** proposed a novel lightweight authentication protocol based on password,smart card and biometric identification that achieves mutual authentication among User,GWN and sensor *** identification can increase the nonrepudiation feature that increases *** security analysis and logical proof,the proposed protocol is proven to have a higher reliability and practicality.

关键词： Authentication biometrics smart card multi-factor

RESS: A Reliable and Effcient Storage Scheme for Bitcoin Blockchain Based on Raptor Code

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Chinese Journal of Electronics 2023年第3期32卷 577-586页

作者： SHI Dongxian WANG Xiaoqing XU Ming kou liang CHENG Hongbing School of Cyberspace Hangzhou Dianzi University College of Information Technology Zhejiang Institute of Economics and Trade College of Computer Zhejiang University of Technology

The Bitcoin system uses a fully replicated data storage mechanism in which each node keeps a full copy of the blockchain. As the number of nodes in the system increases and transactions get more complex, more and more storage space are needed to store block *** scalability of storage has become a bottleneck, limiting the practical application of blockchain. This paper proposes a node storage scheme, called RESS, to integrate erasure coding technology into the blockchain to encode multiple blocks. Under the proposed block grouping method, nodes can reduce the times of coded block decoding. In addition, the coding scheme based on Raptor codes proposed in this paper has linear coding and decoding complexity. The rateless feature of Raptor code helps to achieve high decentralization and scalability of the Bitcoin network. RESS ensures data availability, efficiency and blockchain robustness based on achieving storage space scalability. Experimental results show that the proposed scheme reduces the storage requirements of nodes by nearly an order of magnitude.

关键词： Codes Limiting Scalability Memory Bitcoin Encoding Robustness

Nitrogen additions inhibit nitrification in acidic soils in a subtropical pine plantation: effects of soil pH and compositional shifts in microbial groups

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Journal of Forestry Research 2019年第2期30卷 669-678页

作者： liang kou Xinyu Zhang Huimin Wang Hao Yang Wei Zhao Shenggong Li Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences University of Chinese Academy of Sciences Jiangxi Provincial Key Laboratory of Ecosystem Processes and Information

Plantation forests play a pivotal role in carbon sequestration in terrestrial ecosystems, but enhanced nitrogen(N) deposition in these forests may affect plantation productivity by altering soil N cycling. Hence,understanding how simulated N deposition affects the rate and direction of soil N transformation is critically important in predicting responses of plantation productivity in the context of N loading. This study reports the effects of N addition rate(0, 40, and 120 kg N ha^(-1) a^(-1)) and form(NH_4Cl vs. NaNO_3) on net N mineralization and nitrification estimated by in situ soil core incubation and on-soil microbial biomass determined by the phospholipid fatty acid(PLFA) method in a subtropical pine plantation. N additions had no influences on net N mineralization throughout the year. Net nitrification rate was significantly reduced by additions of both NH_4Cl(71.5) and NaNO_3(47.1%) during the active growing season, with the stronger inhibitory effect at high N rates. Soil pH was markedly decreased by 0.16 units by NH_4Cl additions. N inputs significantly decreased the ratio of fungal-to-bacterial PLFAs on average by 0.28(49.1%) in November. Under NH_4Cl additions, nitrification was positively related with fungal biomass and soil pH. Under NaNO_3 additions,nitrification was positively related with all microbial groups except for bacterial biomass. We conclude that simulated N deposition inhibited net nitrification in the acidic soils of a subtropical plantation forest in China,primarily due to accelerated soil acidification and compositional shifts in microbial functional groups. These findings may facilitate a better mechanistic understanding of soil N cycling in the context of N loading.

关键词： Acidification Atmospheric nitrogen deposition Microbial functional group Nitrification Soil nitrogen transformation

Research progress on silicon/carbon composite anode materials for lithium-ion battery

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Journal of Energy Chemistry 2018年第4期27卷 1067-1090页

作者： Xiaohui Shen Zhanyuan Tian Ruijuan Fan Le Shao Dapeng Zhang Guolin Cao liang kou Yangzhi Bai Center of Nanomaterials for Renewable Energy State Key Laboratory of Electrical Insulation and Power EquipmentSchool of Electrical EngineeringXi'an Jiaotong UniversityXi'an 710049ShaanxiChina Shaanxi Coal and Chemical Technology Institute Co. Ltd.Xi'an 710070ShaanxiChina

Silicon （Si） has been considered as one of the most promising anode material for tHe next generation lithium-ion batteries （LIBs） with high energy densities, due to its high theoretical capacity, abundant availability and environmental friendliness. However. silicon materials with low intrinsic electric and ionic conductivity suffer from huge volume variation during lithiation/delithiation processes leading to the pulverization of Si and subsequently resulting in severe capacity fading of the electrodes. Coupling of Si with carbon （C） realizes a favorable combination of the two materials properties, such as high lithiation capacity of Si and excellent mechanical and conductive properties of C. making silicon/carbon composite （Si/C） ideal candidates for LIBs anodes. In this review, recent progresses of Si/C materials utilized in LIBs are summarized in terms of structural design principles, material synthesis methods, morphological characteristics and electrochemical performances by highlighting the material structures. The mechanisms behind the performance enhancement are also discussed. Moreover, other factors that affect the performance of Si/C anodes, such as prelithiation, electrolyte additives, and binders, are also discussed. We aim to present a full scope of the Si/C-based anodes, and help understand and design future structures of Si/C anodes in LIBs,

关键词： Lithium-ion batteries Anodes Silicon/carbon composite

A Mini Review on Nanocarbon-Based 1D Macroscopic Fibers:Assembly Strategies and Mechanical Properties

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Nano-Micro Letters 2017年第4期9卷 175-192页

作者： liang kou Yingjun Liu Cheng Zhang Le Shao Zhanyuan Tian Zengshe Deng Chao Gao Shaanxi Coal and Chemical Technology Institute Co. Ltd MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Donghua University

Nanocarbon-based materials, such as carbon nanotubes(CNTs) and graphene have been attached much attention by scientific and industrial community. As two representative nanocarbon materials, one-dimensional CNTs and twodimensional graphene both possess remarkable mechanical properties. In the past years, a large amount of work have been done by using CNTs or graphene as building blocks for constructing novel, macroscopic, mechanically strong fibrous materials. In this review, we summarize the assembly approaches of CNT-based fibers and graphene-based fibers in chronological order, respectively. The mechanical performances of these fibrous materials are compared, and the critical influences on the mechanical properties are discussed. Personal perspectives on the fabrication methods of CNT-and graphene-based fibers are further presented.

关键词： One dimensional Macroscopic architectures Carbon nanotubes Graphene fibers Assembly strategies Mechanical performance

Improvements on Calculation Model of Theoretical Combustion Temperature in a Blast Furnace

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Journal of Iron and Steel Research International 2011年第12期18卷 1-5页

作者： WU Sheng-li LIU Cheng-song FU Chang-liang XU Jian kou Ming-yin School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

On the basis of the existing originally modified calculation models of theoretical combustion temperature（TCT）,some factors,such as the combustion ratio of pulverized coal injection（PCI）,the decomposition heat of PCI and the heat consumption of SiO2 in ash reduced in high temperature environment,were amended and improved to put forward a more comprehensive model for calculating *** influences of each improvement on TCT were studied and the results were analyzed compared with those of traditional model and originally modified model,which showed that the present model could reflect the thermal state of a hearth more effectively.

关键词： blast furnace theoretical combustion temperature improved calculation model

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论集合概念的本质——一个案例考察

自然辩证法通讯 2024年第7期46卷 32-40页

作者：寇亮复旦大学哲学学院上海200433

集合概念的演变和现状说明,迭代集合概念对理解集合概念的本质是不够的。我们提出了一种基于证据的认识方法,并以一些案例说明,使用集合论的成果作为证据来理解集合概念的本质如何可能。证据方法还表明,谢拉对投影可决定公理的反驳不能... 详细信息

集合概念的演变和现状说明,迭代集合概念对理解集合概念的本质是不够的。我们提出了一种基于证据的认识方法,并以一些案例说明,使用集合论的成果作为证据来理解集合概念的本质如何可能。证据方法还表明,谢拉对投影可决定公理的反驳不能成立。相反,他的论证可以帮助我们理解集合概念的本质。此外,这种基于证据的认识方法得出的结论具有可错性和理论间的可对比性。

关键词：集合概念投影可决定性证据

Modifying optical properties of ZnO nanowires via strain-gradient

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Frontiers of physics 2013年第5期8卷 509-515页

作者： Xue-Wen Fu Qiang Fu liang-Zhi kou Xin-Li Zhu Rui Zhu Jun Xu Zhi-Min Liao Qing Zhao Wan-Lin Guo Da-Peng Yu State Key Laboratory for Mesoscopic Physics and Electron Microscopy Laboratory Department of Physics Peking University Beijing 100871 China State Key Laboratory for Mechanics and Control of Mechanical Structures and MOE Key Laboratory of IntelligentNano Materials and Devices Institute of Nano Science Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

We conduct systematical cathodolumiuescence study on red-shift of near-band-edge emission energy in elastic bent ZnO nanowires with diameters within the exciton diffusion length （- 200 nm） in liquid nitrogen temperature （81 K）. By charactering the emission spectra of the nanowires with different; local curvatures, we find a linear relationship between strain-gradient and the red-shift of near-band-edge emission photon energy, an elastic strain-gradient effect in semiconductor similar to the famous flexoelectric effect in liquid crystals. Our results provide a new route to understand the inhomogeneous strain effect on the energy bands and optical properties of semiconductors and should be useful for designing advanced nano-optoelectronic devices.

关键词： strain-gradient ZnO nanowire cathodoluminescene exciton energy energy bands

ZnO Interface Modified LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)Toward Boosting Lithium Storage

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Energy & Environmental Materials 2020年第4期3卷 522-528页

作者： Yunyan Li Xifei Li Junhua Hu Wen Liu Hirbod Maleki Kheimeh Sari Dejun Li Qian Sun liang kou Zhanyuan Tian Le Shao Cheng Zhang Jiujun Zhang Xueliang Sun Tianjin International Joint Research Center of Surface Technology for Energy Storage Materials Energy&Materials Engineering CenterCollege of Physics and Materials ScienceTianjin Normal UniversityTianjin 300387China Xi’an Key Laboratory of New Energy Materials and Devices Institute of Advanced Electrochemical Energy&School of Materials Science and EngineeringXi’an University of TechnologyXi’an 710048Shaanxi China State Center for International Cooperation on Designer Low-carbon&Environmental Materials(CDLCEM) Zhengzhou University100 Kexue AvenueZhengzhou 450001China Department of Mechanical and Materials Engineering University of Western OntarioLondonOntario N6A 5B9Canada Shaanxi Coal Chem Ind Technol Res Inst Co Ltd Xian Shaanxi 710070China Department of Chemistry College of Sciences/Institute for Sustainable EnergyShanghai UniversityShanghai 200444China

In this work,an amorphous ZnO was coated on LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)(NCM)using a sol-gel strategy *** NCM coated with 1 wt.%Zn O and a thickness of about 3 nm exhibits an improved cycling performance,accompanied by a lower capacity fading(from 194.8 to 133.8 m Ah g^(-1),i.e.,68%)than that of the pristine one(i.e.,only 34%)after 300 cycles at 0.2 *** cyclic voltammetry(CV)and electrochemical impedance spectroscopy(EIS)indicate that the Zn O coating can improve extraction/insertion of Li+and inhibit the increase in impedance of the NCM cathode *** approach may benefit the performance improvement of the Ni-rich cathode materials in Lithium-ion batteries(LIBs).

关键词： cathode materials LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2) lithium-ion batteries ZnO coating