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Sharing of Encrypted Lock Keys in the Blockchain-Based Renting House System from Time- and Identity-Based Proxy Reencryption

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China Communications 2022年第5期19卷 164-177页

作者： Zhiwei Wang liping qian Danwei Chen Guozi sun School of Computer Nanjing University of Posts and TelecommunicationsNanjing 210023China Jiangsu Key Laboratory of Big Data Security and Intelligent Processing Nanjing 210023China Guangxi Key Laboratory of Cryptography and Information Security Department of Computer SciencesGuilin University of Electronic TechnologyGuilin 541004China

To design an efficient protocol for sharing the encrypted lock keys in the renting house system,we introduce a new notion called time-and identitybased proxy reencryption(TIPRE)and the blockchain *** CPA secure TIPRE scheme is constructed from Green et al.’s identity-based proxy reencryption scheme by adding the time *** every time period,a time stamp authority generates a public key embedded with the current time stamp for each *** our protocol for the renting house system,the TIPRE scheme is the primary building block,and the blockchain platform serves instead of a trusted third party,such as a real estate agency between landlords and *** TIPRE scheme allows the landlord to change the lock key at each time period for *** blockchain platform allows the landlords and tenants to directly interact,and all of the interactions are recorded in the blockchain database to provide the desired security requirements,such as nonrepudiation and ***,we provide the secure analysis of our protocol and test its performance by implementing it in the MacBook Pro and the Intel Edison development platforms.

关键词： identity-based proxy reencryption time stamp renting houses system blockchain

Deep Learning based Efficient Edge Slicing for System Cost Minimization in Wireless Networks

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Journal of Communications and Information Networks 2024年第2期9卷 162-175页

作者： Wei Jiang Daquan Feng liping qian Yao sun College of Information Engineering Zhejiang University of TechnologyHangzhou 310023China Shenzhen Key Laboratory of Digital Creative Technology Guangdong Province Engineering Laboratory for Digital Creative TechnologyCollege of Electronics and Information EngineeringShenzhen UniversityShenzhen 518060China James Watt School of Engineering University of GlasgowG128QQScotlandUK

It is widely recognized that the future wireless networks are able to efficiently slice heterogeneous resources to provide customized services for various use cases. However, it is challenging to meet the diverse requirements of ever-growing applications, especially the stringent requirements of numerous delay-sensitive and/or computation-intensive applications. To tackle this challenge, we should not only consider user admission control to cope with resource limitations, but also make resource management more intelligent and flexible to meet diverse service needs. Taking advantages of mobile edge computing(MEC)and network slicing, in this paper, we propose deep edge slicing(DES),to jointly optimize user admission control and resource scheduling with the aim of minimizing the system cost while guaranteeing multitudinous quality-of-service (QoS) requirements. Specifically, we first apply a deep reinforcement learning approach to select the optimal set of access users with different service requests for maximizing resource *** a deep learning algorithm is employed to predict traffic data for allocating the communication and computing resources to different slices in advance. Finally, we realize the dynamic scheduling of heterogeneous resources by solving the optimization problem of minimizing the system cost. Simulation results demonstrate that DES can greatly reduce the system cost compared to other benchmarks.

关键词： deep learning mobile edge computing user admission control resource scheduling

Microstructure and Thermal Conductivity of As-Cast and As-Solutionized Mg–Rare Earth Binary Alloys

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Journal of Materials Science & Technology 2017年第11期33卷 1240-1248页

作者： liping Zhong Jian Peng song sun Yongjian Wang Yun Lu Fusheng Pan State Key Laboratory of Mechanical Transmission College of Materials Science and Engineering Chongqing University Chongqing 400044 China Chongqing Academy of Science and Technology Chongqing 401127 China Graduate School & Faculty of Engineering Chiba University Chiba 263-8522 Japan

The microstructure and thermal conductivity of four groups of Mg–rare earth（RE） binary alloys（Mg–Ce,Mg–Nd, Mg–Y and Mg–Gd） in as-cast and as-solutionized states were systematically studied. Thermal conductivity was measured on a Netzsch LFA457 using laser flash method at room temperature. Results indicated that for as-cast alloys, the volume fraction of second phases increased with the increase of alloying elements. After solutionizing treatment, a part or most of second phases were dissolved in α-Mg matrix, except for Mg–Ce alloys. The thermal conductivity of as-cast and as-solutionized Mg–RE alloys decreased with the increase of concentrations. The thermal conductivity of as-solutionized Mg–Nd,Mg–Y and Mg–Gd alloys was lower than that of as-cast alloys. Thermal conductivity of as-solutionized Mg–Ce alloys was higher than that of as-cast alloys, because of the elimination of lattice defects and fine dispersed particles during solutionizing treatment. Different RE elements have different influences on the thermal conductivity of Mg alloys in the following order： Ce 〈 Nd 〈 Y 〈 Gd. Ce has the minimum effect on thermal conductivity of Mg alloys, because of the very low solubility of Ce in the α-Mg matrix. The variations in the atomic radius of the solute elements with Mg atom（ r）, valence, configuration of extranuclear electron of the solute atoms, and the maximum solid solubility of elements in the α-Mg matrix were suggested to be the main reasons for the differences in thermal conductivity of resulting Mg–RE alloys.

关键词： Mg alloys Rare earth elements Microstructure Thermal conductivity

Effect of inlet volute wrap angle on the flow field and performance of double inlet gas cyclones

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Particuology 2023年第6期77卷 29-36页

作者： Zetao Wang Guogang sun Zhengyuan song Shiwei Yuan Zhen qian College of Mechanical and Transportation Engineering China University of PetroleumBeijing102249China State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China

In response to the divergent understanding of double inlet cyclone performance in the literature,the effect of inlet volute wrap angle on the performance and flow field of double inlet cyclone separator was studied by Computational Fluid Dynamic(CFD)*** results showed that the inlet volute wrap angle can affect the comparison results of the single and double inlet gas cyclones with the same total inlet cross-sectional area and velocity.0°and 90°volute double inlet improved the efficiency mainly by separating particles below 10μm,while 180°volute double inlet had no separation advantage for any particles,so the symmetrical double inlet does not always improve the efficiency,and the appropriate inlet volute wrap angle should be selected according to the actual situation,otherwise,the expected performance requirements of the symmetrical double inlet cyclone cannot be *** with the flow field,it is found that the inlet volute wrap angle changed the tangential velocity of the sym-metrical double inlet cyclone separator,thus changing the performance.

关键词： Cyclone separator Inlet volutewrapangle Efficiency Pressure drop Double inlet

Application of biologic silicon in modern sedimentary section to reconstruction of phytoplankton changes in the East China Sea and the Huanghai Sea during last 200 years

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Acta Oceanologica Sinica 2012年第2期31卷 70-77页

作者： YANG qian song Xianli sun Yao HUANG Jiansheng Key Laboratory of Marine Chemistry Theory and Technology Ministry of EducationOcean University of ChinaQingdao 266100China Yellow Sea Fisheries Research Institute Chinese Fisheries Science AcademyQingdao 266071China Mariculture Institute of Shandong Province Qingdao 266002China Xiamen University Xiamen 361005China

Biomarkers had been widely used to reconstruct phytoplankton productivity, and this method was applied in the East China Sea and the Huanghai Sea （Yellow Sea）. In this study, Biologic Silicon （BSi） was used as productivity proxy to reconstruct productivity change of phytoplankton during last 200 years. The results show that the BSi contents of surficial＇sediments were in the range of 0.018%-2.516%, averaging 0.726%, and had a similar variation trend with phytoplankton biomass. The vertical distribution profiles revealed that BSi contents were relatively stable, in accordance with the variations of the contemporary phytoplankton standing crop index. According to the stability analysis of BSi in sediments, BSi was not degradaded for the past two hundred years and remained in sediments steadily. Thus, BSi in sediments had the potential to invert paleoproductivity. To conduct further survey, the linear regression equation between BSi contents and phytoplankton biomass index could be used to calculate the phytoplankton productivity by BSi, so that paleoproduetivity may be reconstructed during last 200 years.

关键词： typical sea areas of the East China Sea and the Huanghai Sea sediment BSi productivity reconstruction

Effects of Si and Cr on Complete Decarburization Behavior of High Carbon Steels in Atmosphere of 2 vol.%O2

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Journal of Iron and Steel Research International 2016年第12期23卷 1316-1322页

作者： Yang-bo LIU Wei ZHANG qian TONG Qi-song sun Shougang Research Institute of Technology Beijing 100048China Beijing Key Laboratory of Green Recyclable Process for Iron&Steel Production Technology Beijing 100048China

The effects of chemical compositions, especially silicon and chromium contents, on the complete decarburization behaviors of steels in atmosphere of 2 vol. %O2 and 98 vol. % N2 were investigated by using a simuhaneous thermal analyzer. Complete decarburization was observed at both 750 and 800 ℃ for 60Si2MnA steel, while 750℃ only for 92A steel. For GCr15 steel, no decarburization was found at 750 or 800 ℃, and only partial decarburization was observed at 850 ℃. It indicates that silicon promotes while chromium prevents the complete decarburization of steels in atmosphere with 2 vol. % O2. The main reason is that silicon increases while chromium reduces the equilib rium concentration of ferrite at the interface of ferrite and austenite, which results in the complete decarburization.

关键词： complete deearburization silicon chromium low oxygen concentration oxide scale

Novel energy dissipative method on the adaptive spatial discretization for the Allen–Cahn equation

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Chinese Physics B 2021年第7期30卷 107-115页

作者： Jing-Wei sun Xu qian Hong Zhang song-He song Department of Mathematics National University of Defense TechnologyChangsha 410073China State Key Laboratory of High Performance Computing National University of Defense TechnologyChangsha 410073China

We propose a novel energy dissipative method for the Allen–Cahn equation on nonuniform *** spatial discretization,the classical central difference method is utilized,while the average vector field method is applied for time *** with the average vector field method on the uniform mesh,the proposed method can involve fewer grid points and achieve better numerical performance over long time *** is due to the moving mesh method,which can concentrate the grid points more densely where the solution changes *** experiments are provided to illustrate the advantages of the proposed concrete adaptive energy dissipative scheme under large time and space steps over a long time.

关键词： moving mesh energy dissipative average vector field method Allen–Cahn equation

Spatiotemporal Evolution Characteristics of Urban Land Surface Temperature Based on Local Climate Zones in Xi’an Metropolitan,China

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Chinese Geographical Science 2023年第6期33卷 1001-1016页

作者： ZHANG liping ZHOU Liang YUAN Bo HU Fengning ZHANG qian WEI Wei sun Dongqi Faculty of Geomatics Lanzhou Jiaotong UniversityLanzhou730070China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing100101China Department of Geography and Environment University of Hawaii at ManoaHonoluluHawaii96822USA College of Geography and Environmental Science Northwest Normal UniversityLanzhou730070China

Local climate zones(LCZs)are an effective nexus linking internal urban structures to the local climate and have been widely used to study urban thermal ***,few studies considered how much the temperature changed due to LCZs transformation and their *** paper quantified the change of urban land surface temperature(LST)in LCZs transformation process by combining the land use transfer matrix with zonal statistics method during 2000–2019 in the Xi’an *** results show that,firstly,both LCZs and LST had significant spatiotemporal variations and *** period when the most LCZs were converted was also the LST rose the fastest,and the spatial growth of the LST coincided with the spatial expansion of the built type ***,the LST difference between land cover type LCZs and built type LCZs gradually *** LST rose more in both built type LCZs transferred in and ***,the Xi’an-Xianyang profile showed that the maximum temperature difference between the peaks and valleys of the LST increased by 4.39℃,indicating that localized high temperature phenomena and fluctuations in the urban thermal environment became more pronounced from 2000 to 2019.

关键词： urban land surface temperature(LST) local climate zones(LCZs) thermal environment time series urban sustainable development Xi’an metropolitan,China

Molecular Characterization of C_(9+)Aromatics in Gasoline by Gas Chromatography-Mass Spectrometry

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China Petroleum Processing & Petrochemical Technology 2023年第2期25卷 81-91页

作者： Han Xu song Chunxia qian Qin Li Changxiu sun Xinyuan Sinopec Research Institute of Petroleum Processing Co. Ltd.Beijing 100083China

The comprehensive characterization of heavy aromatic hydrocarbons in gasoline is important to optimize the blending process and understand the correlation between aromatics content and engine particulate ***,most current analysis methods can only provide the composition of C_(8)/C_(8-) *** this study,a simple and fast gas chromatography-mass spectrometry(GC-MS)method to identify and quantify C_(9+)aromatics in gasoline was developed.A selected ion monitoring model was employed to eliminate interference from non-aromatic compounds in the detection of target compounds,as well as that between target compounds with different molecular *** identification of C_(9+)aromatics was based on the retention time of model compounds,combined with characteristic mass fragment ions,boiling points,and retention ***-nine C_(9)–C_(12)aromatic compounds were quantified based on the calibration of representative model compounds,and the method demonstrated good linearity,and high accuracy and ***,the developed methodology was successfully applied to the analysis of gasoline fractions from the reforming,pyrolysis,straight-run,delayed coking,and catalytic cracking processes,as well as commercial *** results showed that C_(9)aromatics were the predominant aromatics in all gasoline samples,followed by C10 *** such as C_(9)H_(12)and C_(10)H_(14)were the main components in the reforming,straight-run,delayed coking,and catalytic cracking gasoline fractions,as well as in the commercial gasolines,in which 1,2,4-trimethylbenzene and 3-ethyltoluene were dominant;in contrast,aromatics with higher degrees of unsaturation such as indene were the most abundant aromatics in the pyrolysis gasoline fraction.

关键词： gasoline C_(9+)aromatics heavy aromatics GC-MS