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ErlangShen:基于流水线低访问开销的图式区块链高效事务执行机制

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电子与信息学报 2024年第5期46卷 2111-2121页

作者：肖江吴恩平张世桀伏子豪金海大数据技术与系统国家地方联合工程研究中心武汉430074 服务计算技术与系统教育部重点实验室武汉430074 集群与网格计算湖北省重点实验室武汉430074 华中科技大学计算机科学与技术学院武汉430074

基于有向无环图(DAG)的图式区块链能够显著提升系统性能,已成为近年来业界的研究热点。相较于传统串行化的链式区块链,图式区块链可在单位时间内并发处理大量事务从而提升吞吐量。随着事务量的激增,图式区块链面临事务执行效率低的瓶颈... 详细信息

基于有向无环图(DAG)的图式区块链能够显著提升系统性能,已成为近年来业界的研究热点。相较于传统串行化的链式区块链,图式区块链可在单位时间内并发处理大量事务从而提升吞吐量。随着事务量的激增,图式区块链面临事务执行效率低的瓶颈问题,即海量事务执行对状态数据访问的需求大幅增加,导致高昂的输入/输出(I/O)开销。实现低I/O访问主要包括两方面的全新挑战:一方面,图式区块链若直接采用传统的事务预取机制,将因执行逻辑不一致引入大量的陈旧读;另一方面,针对不同账户的状态访问会在默克尔树的高层节点中造成重复的I/O开销。为此,本文设计基于流水线的图式区块链高效事务执行机制—ErlangShen,包括Epoch粒度的状态预取机制和默克尔高层路径缓存机制来分别减少陈旧读的数量和重复的I/O开销。具体而言,ErlangShen充分分析并利用了事务访问频次的冷热特征,将访问热事务的逻辑执行与冷事务的状态预取并行化,以避免状态预取对事务执行的影响。此外,为了进一步提升事务执行的吞吐量,根据访问冷热状态事务的特性设计了定制化的并发控制方法。实验结果表明,ErlangShen机制能够减少约90%的陈旧读数量,与最新图式区块链事务处理机制Nezha相比,可将性能提升3~4倍。

关键词：区块链图式区块链 I/O优化并发控制状态树

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基于机器学习的配用电场景信号覆盖优化技术

电波科学学报 2024年第3期39卷 518-525页

作者：谷毅富子豪王登政江璟陈之怡国家电网有限公司北京100031 国网经济技术研究院有限公司北京102209

配用电场景是电力系统的重要组成部分,其无线网络设计对于提高配用电终端的信号质量、实现全面监测和管理、提升电力系统效率、支持智能化决策和控制,以及促进能源管理和节能减排具有重要的意义。本文面向配电网典型场景,提出基于机器... 详细信息

配用电场景是电力系统的重要组成部分,其无线网络设计对于提高配用电终端的信号质量、实现全面监测和管理、提升电力系统效率、支持智能化决策和控制,以及促进能源管理和节能减排具有重要的意义。本文面向配电网典型场景,提出基于机器学习的配电网场景覆盖优化技术。首先,根据实际电力业务终端和需求,建立配用电典型场景环境模型;其次,利用射线追踪技术生成信道大数据,并建立基于广义回归神经网络(general regression neural network, GRNN)的路损预测模型;最后,联合总覆盖率、平均单节点覆盖率、重复覆盖率作为奖励值,利用强化学习优化节点部署位置。仿真结果表明,所提GRNN路损预测模型可精确预测路损,所提联合多维指标的奖励函数计算方法可有效提高网络收敛速率。本文所提算法对配电网无线网络规划和设计具有重要意义。

关键词：配用电覆盖优化机器学习强化学习信道建模

新型配电网多元业务与多模通信适配性评估方法

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电力建设 2024年第1期45卷 1-12页

作者：董朝武肖智宏辛培哲富子豪江璟国网经济技术研究院有限公司北京市102209

随着新型电力系统发展快速推进,分布式新能源、储能、电动汽车等新业务将大规模接入配电网,适合的通信技术是支撑业务传输、保障配电网安全可靠运行的重要手段。文章对新型电力系统背景下配电网业务的传输需求与可用通信手段的技术性能... 详细信息

随着新型电力系统发展快速推进,分布式新能源、储能、电动汽车等新业务将大规模接入配电网,适合的通信技术是支撑业务传输、保障配电网安全可靠运行的重要手段。文章对新型电力系统背景下配电网业务的传输需求与可用通信手段的技术性能进行梳理,提出了考虑接入、覆盖、经济、可靠、安全的多维度评价指标体系;其次,提出了基于贝叶斯最优最劣(Bayesian best-worst method,BBWM)和折中解决方法(measurement alternatives and ranking according to compromise solution,MARCOS)的主客观赋权适配性综合分析模型;最后对中压、低压配电网典型业务与通信技术开展适配性分析,进而提出配电网全业务与通信技术适配体系。

关键词：新型电力系统配电通信网贝叶斯最优最劣折中解决方法(MARCOS)

A fuzzy Clustering Algorithm Based on Multipath Component Trajectory for Millimeter Wave Radio Channels

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China Communications 2022年第11期19卷 99-111页

作者： Fei Du Yu Zhang Qingliang Li Xinyue Zhang Bo Zhu zihao fu Suiyan Geng Xiongwen Zhao State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources School of Electrical and Electronic EngineeringNorth China Electric Power UniversityBeijing 102206China Hebei Key Laboratory of Power Internet of Things Technology North China Electric Power UniversityBaoding 071003HebeiChina National Key Laboratory of Electromagnetic Environment China Research Institute of Radiowave PropagationQingdao 266107China

Time-varying channel modeling plays an important role for many applications in time-variant scenarios,while most clustering algorithms focus on static channels and cannot accurately model the channel time-evolution *** this paper,a fuzzy clustering algorithm based on multipath component(MPC)trajectory is ***,both the distance and velocity similarities of the MPCs in different snapshots are taken into account to track the MPC trajectory,in which the fuzzy scheme and a kernel function are used to calculate the distance and velocity similarities,***,a fuzzy MPC trajectory clustering algorithm is proposed to cluster the MPCs in multiple *** MPCs in a snapshot are clustered according to the membership,which is defined as the probability that a MPC belongs to different ***,time-varying channels at 28 GHz are simulated to validate the performance of our proposed *** results show that our proposed algorithm is able to accurately identify the clusters in time-varying channels compared with the existing clustering algorithms.

关键词： channel modeling time-varying clustering multiple path component MPC trajectory 6G

Nanocomposite: Keggin-type Co_(4)-polyoxometalate@cobaltporphyrin linked graphdiyne for hydrogen evolution in seawater

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Nano Research 2024年第3期17卷 1281-1287页

作者： Jiejie Ping Danyang He Fei Wang Nan Wang Yi-cheng fu zihao Xing Zhiyu Jia Guo-Yu Yang Key Laboratory of Cluster Science Ministry of EducationSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education Facluty of Chmeistry Northeast Normal UniversityChangchun 130024China Peking University Third Hospital Beijing 100190China

Polyoxometalate-based nanocomposites with electrocatalytic activity have been applied in hydrogen evolution reactions(HER).Seawater as the main water resource on the earth should be developed as the water electrolysis to prepare high-purity *** this paper,we used two synthesis strategies to prepare the nanocomposite Co_(4)-POM@Co-PGDY(Co_(4)-POM:the Kegging-type microcrystals of K_(10)[Co_(4)(PW_(9)O_(3)4)2]and Co-PGDY:cobalt-porphyrin linked graphdiyne)with excellent activity for ***-PGDY as the porous material is applied not only as the protection of microcrystals towards the metal ion in seawater but also as the co-electrocatalyst of Co_(4)-***_(4)-POM@Co-PGDY exhibits excellent HER performance in seawater electrolytes with low overpotential and high stability at high ***,we have observed a key H_(3)O+intermediate emergence on the surface of nanocomposite during hydrogen evolution process in seawater by Raman synchrotron radiation-based Fourier transform infrared(SR-FTIR).The results in this paper provide an effective strategy for preparing polyoxometalate-based electrocatalysts with high-performance toward hydrogen evolution reaction.

关键词： polyoxometalate graphdiyne seawater hydrogen evolution reaction

On the Understandings of Dielectric Constant and Its Impacts on the Photovoltaic Efficiency in Organic Solar Cells

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Chinese Journal of Chemistry 2021年第2期39卷 381-390页

作者： zihao fu Xuning Zhang Hong Zhang Yanxun Li Huiqiong Zhou Yuan Zhang School of Chemistry Beijing Advanced Innovation Center for Biomedical EngineeringBeihang UniversityNo.37 Xueyuan RoadBeijing100191 China Key Laboratory of Nanosystem and Hierachical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing100190 China

Dielectric constant(ε)is an important parameter affecting the power conversion efficiency of organic solar cells(OSC).Increasingεof bulk heterojunctions in general can benefit the performance of OSCs,as an increasedεwill reduce the influence of Coulomb interaction between weakly bound electron-hole pairs on charge-transfer states or bimolecular recombination involving mobile carriers to reduce geminate and nongeminate *** this review,we overview the current understandings on dielectric constant and its impacts on exciton dissociation and voltage losses in OSCs and summarize recent efforts attempting to modify the dielectric properties of OSC materials through synthetic *** further discuss the commonly adopted techniques for determining the parameter ofεwith stressing the testing conditions that may affect the accuracy of *** last,we suggest that novel experimental methods to improve the dielectric constant and resultant physical processes in OSCs will be appreciated,which helps enrich the existing strategy reservoir toward enhancement of photovoltaic efficiencies.

关键词： Amorphous materials Donor-acceptor systems Energy conversion Nanostructures Photolysis

Neural Network and GBSM Based Time-Varying and Stochastic Channel Modeling for 5G Millimeter Wave Communications

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China Communications 2019年第6期16卷 80-90页

作者： Xiongwen Zhao Fei Du Suiyan Geng Ningyao Sun Yu Zhang zihao fu Guangjian Wang School of Electrical and Electronic Engineering North China Electric Power UniversityBeijing 102206China Huawei Technologies Co.Ltd. Chengdu Research InstituteChengdu 611731China

In this work,a frame work for time-varying channel modeling and simulation is proposed by using neural network(NN)to overcome the shortcomings in geometry based stochastic model(GBSM)and simulation *** NN models are developed for modeling of path loss together with shadow fading(SF)and joint small scale channel *** NN models can predict path loss plus SF and small scale channel parameters accurately compared with measurement at 26 GHz performed in an outdoor *** time-varying path loss and small scale channel parameters generated by the NN models are proposed to replace the empirical path loss and channel parameter random numbers in GBSM-based framework to playback the measured channel and match with its ***,the sparse feature of clusters,delay and angular spread,channel capacity are investigated by a virtual array measurement at 28 GHz in a large waiting hall.

关键词： time-varying channel neural network cluster channel modeling virtual array measurement 5G

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矩的显式积分算法研究与应用

北京航空航天大学学报 2015年第4期41卷 727-731页

作者：付子豪龚光红北京航空航天大学自动化科学与电气工程学院北京100191

矩的求解通常被用于求解有限元、体积、惯性矩等问题中.基于矩的叠加性,首先给出了在三维空间中计算域的离散方式,并推导了矩的显式积分公式,随后将其推广到n维空间中,该表达式易于在计算机上实现;设计了矩的并行计算算法,并通过Fortran... 详细信息

矩的求解通常被用于求解有限元、体积、惯性矩等问题中.基于矩的叠加性,首先给出了在三维空间中计算域的离散方式,并推导了矩的显式积分公式,随后将其推广到n维空间中,该表达式易于在计算机上实现;设计了矩的并行计算算法,并通过Fortran和Python混编的方式,实现了矩的并行计算;对多重精度下的样例数据给出了一个算例,实现了零阶矩和二阶矩的计算,并和串行算法、逐次降维算法作出比较,进行了效率分析和误差分析.结果显示,矩的显式积分并行计算算法易于程序实现,并且在效率上高于串行算法,能够很容易推广到高维空间,该算法具有高度可并行性,误差主要来自计算域离散.

关键词：矩显式积分公式并行计算逐次降维计算域离散

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分子模拟研究苯酚在大气冰表面的吸附行为

环境化学 2023年第7期42卷 2262-2272页

作者：蔡雪莹付自豪谢宏彬大连理工大学环境学院大连116024

苯酚是大气中重要的有毒污染物,然而其在大气冰表面的吸附行为仍不明确.本研究使用巨正则蒙特卡罗(GCMC)模拟方法,基于TIP5P水力场和优化的苯酚力场,模拟了温度200 K条件下,苯酚在六边形(Ih)冰0001表面的吸附行为.研究表明,苯酚在冰表... 详细信息

苯酚是大气中重要的有毒污染物,然而其在大气冰表面的吸附行为仍不明确.本研究使用巨正则蒙特卡罗(GCMC)模拟方法,基于TIP5P水力场和优化的苯酚力场,模拟了温度200 K条件下,苯酚在六边形(Ih)冰0001表面的吸附行为.研究表明,苯酚在冰表面的吸附等温线具有两个平台期,达到第一个平台期后,苯酚单层吸附饱和并进入快速增长期,随后至吸附凝结点,达到第二个平台期.当苯酚分子吸附量较小时,苯酚独立地吸附在冰表面,吸附行为符合Langmuir吸附类型;随着苯酚分子吸附量增加,冰表面的苯酚分子间产生相互作用,导致偏离了Langmuir吸附等温线.在不同吸附量情况下,苯酚与冰表面分子形成的氢键类型均是以苯酚—OH上的氢原子与冰表面氧原子之间形成的氢键为主.

关键词：苯酚冰表面吸附行为巨正则蒙特卡罗模拟.

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