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塔北地区奥陶系碳酸盐岩缝洞充填方解石的阴极发光特征及对成岩环境的指示意义

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油气地质与采收率 2015年第4期22卷 54-58页

作者：韦东晓沈安江王莹乔占峰朱永峰中国石油勘探开发研究院杭州地质研究院浙江杭州310023 中国石油碳酸盐岩储层重点实验室浙江杭州310023 中国石油塔里木油田分公司新疆库尔勒841000

对碳酸盐矿物和结构组分进行阴极发光分析可以直观、快捷地研究碳酸盐岩储层的成岩环境和成因。基于塔北地区奥陶系碳酸盐岩缝洞充填方解石阴极发光特征分析,结合Mn2+和Fe2+含量及流体包裹体均一温度,深入研究其对成岩环境的指示作用。... 详细信息

对碳酸盐矿物和结构组分进行阴极发光分析可以直观、快捷地研究碳酸盐岩储层的成岩环境和成因。基于塔北地区奥陶系碳酸盐岩缝洞充填方解石阴极发光特征分析,结合Mn2+和Fe2+含量及流体包裹体均一温度,深入研究其对成岩环境的指示作用。结果表明:Mn2+和Fe2+含量及发光特征可大致反映成岩环境的氧化还原条件,明亮发光(Mn2+含量高)表明成岩环境为还原条件,也可能是与不发光胶结作用相关的氧化水停滞有关;昏暗—不发光表明成岩环境为氧化条件,是Mn2+趋向于被氧化为高价态而不易置换Ca2+进入晶格所致;不同产状的缝洞充填方解石发光性、Mn2+和Fe2+含量及两者比值各异,指示不同的成岩环境及充填期次,反映研究区缝洞形成及充填的复杂性和多期性。

关键词：阴极发光缝洞充填方解石成岩环境奥陶系塔北地区

Elliptical Cell Based Beamforming Design with an Improved β-Fairness Power Allocation for HSR Communication Systems

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China Communications 2022年第5期19卷 112-128页

作者： Ximei Liu Deli qiao School of Communication and Electronic Engineering East China Normal UniversityShanghai 200241China

In this paper,a beamforming scheme to improve the coverage in high-speed railway communication systems is investigated.A dedicated coverage model,where the coverage cell is an ellipse rather than the traditional circular or linear,is considered.Based on the elliptical coverage cell,an optimization problem for the beamforming design is formulated to maximize the percentage of railway coverage,subject to the constraints on equal expected designed propagation gain(the gain obtained by a combination of designed beam and propagation channel)on the elliptical curve,i.e.,the expectation of designed propagation gain on the elliptical curve are all equal.Considering that the coverage can be improved by increasing the minimum designed propagation gain on the railway,the problem can be recast to maximizing the equal expected designed propagation gain on the elliptical curve.Subsequently,a beamforming design with an improved β-fairness power allocation,where the optimization problem is formulated to maximize the minimum expected received power over time with the constraints on elliptical cell based beamforming and mobile service amount,is proposed to further improve the coverage.An alternating iteration algorithm is developed to find the optimal beamforming vector and the instantaneous transmit power.Through numerical results,it is found that the beamforming designed on the elliptical curve covers longer railway than beamforming designed on the railway directly,and the coverage of elliptical cell based beamforming can be increased with the eccentricity.In addition,beamforming with the improvedβ-fairness power allocation can further improve the railway coverage and mobile service amount simultaneously.Moreover,it is shown that the larger eccentricity of the ellipse with appropriately chosen BS location,the larger coverage distance.

关键词： high-speed railway communication elliptical cell based beamforming coverage power allocation mobile service amount

Augmented reality-based BIM multi-user collaboration system

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The Journal of China Universities of Posts and Telecommunications 2022年第1期29卷 71-80页

作者： Sun Heng qiao Xiuquan Shanxi Transportation Planning Survey and Design Institute Company Limited Taiyuan 030024China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China

The rapid development of building information modelling(BIM) and its enabling technologies has attracted extensive attention in the field of architecture, engineering and construction(AEC). By combining BIM models with the real world, the potential of BIM can be further exploited with the help of augmented reality(AR) technology. However, a BIM model usually involves a huge amount of data. Considering the limited computing capability of current mobile devices, these applications therefore suffer from significant performance problems, especially model loading and rendering problems. To this end, an AR-based multi-user BIM collaboration system, which can realise the on-demand dynamical loading of the BIM model by using the block-wise loading strategy of model transformation, thus solving the problem of model loading delay, was proposed. In addition, dynamic rendering technology is adopted to solve the problem of rendering lag. Experimental results show that the realisation of virtual-reality fusion and interaction for the BIM model and remote multi-user collaboration can effectively improve work efficiency and intelligence in the engineering field.

关键词： building information modelling augmented reality multi-user collaboration block-wise loading dynamic rendering

Salicylic acid biosynthesis is not from phenylalanine in Arabidopsis

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Journal of Integrative Plant Biology 2023年第4期65卷 881-887页

作者： Jie Wu Wentao Zhu qiao Zhao Shenzhen Key Laboratory of Synthetic Genomics Guangdong Provincial Key Laboratory of Synthetic GenomicsShenzhen Institute of Synthetic BiologyShenzhen Institute of Advanced Technologythe Chinese Academy of SciencesShenzhen 518055China Department of Applied Chemistry Innovation Center of Pesticide ResearchCollege of ScienceChina Agricultural UniversityBeijing 100193China Center for Plant Biology School of Life SciencesTsinghua UniversityBeijing 100084China

The phytohormone salicylic acid(SA)regulates biotic and abiotic stress responses in plants.Two distinct biosynthetic pathways for SA have been well documented in plants:the isochorismate(IC)pathway in the chloroplast and the phenylalanine ammonia-lyase(PAL)pathway in the cytosol.However,there has been no solid evidence that the PAL pathway contributes to SA biosynthesis.Here,we report that feeding Arabidopsis thaliana with Ring-13C-labeled phenylalanine(13C6-Phe)resulted in incorporation of the13C label not into SA,but into its isomer 4-hydroxybenzoic acid(4-HBA)instead.We obtained similar results when feeding13C6-Phe to the SA-deficient ics1 ics2 mutant and the SA-hyperaccumulating mutant s3h s5h.Notably,we detected13C6-SA when13C6-benzoic acid(BA)was provided,suggesting that SA can be synthesized from BA.Furthermore,despite the substantial accumulation of SA upon pathogen infection,we did not observe incorporation of13C label from Phe into SA.We also did not detect13C6-SA in PAL-overexpressing lines in the kfb01 kfb02 kfb39 kfb50 background after being fed13C6-Phe,although endogenous PAL levels were dramatically increased.Based on these combined results,we propose that SA biosynthesis is not from Phe in Arabidopsis.These results have important implications for our understanding of the SA biosynthetic pathway in land plants.

关键词： benzoic acid IC pathway isotopic labeling PAL pathway salicylic acid

The spectrum and stability of travelling pulses in a coupled FitzHugh-Nagumo equation

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Science China Mathematics 2024年第5期67卷 975-1010页

作者： Qi qiao Xiang Zhang School of Mathematical Sciences Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of Scientific and Engineering Computing(Ministry of Education) and Shanghai Frontier Science Center of Modern Analysis(CMA-Shanghai)Shanghai Jiao Tong UniversityShanghai 200240China

For a coupled slow-fast FitzHugh-Nagumo(FHN)equation derived from a reaction-diffusionmechanics(RDM)model,Holzer et al.(2013)studied the existence and stability of the travelling pulse,which consists of two fast orbit arcs and two slow ones,where one fast segment passes the unique fold point with algebraic decreasing and two slow ones follow normally hyperbolic critical curve segments.Shen and Zhang(2021)obtained the existence of the travelling pulse,whose two fast orbit arcs both exponentially decrease,and one of the slow orbit arcs could be normally hyperbolic or not at the origin.Here,we characterize both the nonlinear and spectral stability of this travelling pulse.

关键词： coupled FitzHugh-Nagumo equation singular perturbation travelling pulse spectrum nonlinear stability spectral stability

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波谱匹配支持的遥感专题地物自适应提取

数据采集与处理 2012年第3期27卷 294-298页

作者：乔程骆剑承沈占锋朱志文胡晓东中国科学院遥感应用研究所北京100101 中国科学院研究生院北京100049

为贴合地物表现的多样性和复杂性,提出一种波谱匹配支持下的遥感影像专题地物自适应提取方法,经过专题地物端元选取、波谱匹配、影像自动分割、"整体-局部"的空间转换,以及局部针对性、精细化地迭代逼近等一系列相互衔接的算法,全面、... 详细信息

为贴合地物表现的多样性和复杂性,提出一种波谱匹配支持下的遥感影像专题地物自适应提取方法,经过专题地物端元选取、波谱匹配、影像自动分割、"整体-局部"的空间转换,以及局部针对性、精细化地迭代逼近等一系列相互衔接的算法,全面、准确地提取遥感影像上的专题地物。通过在ETM+影像上水体和裸地的提取实验,并与最大似然法和SVM分类结果比较,证明了该方法对多样性专题地物提取的有效性和普适性。

关键词：专题地物提取波谱匹配遥感

A hybrid Fast Multipole Method for cosmological N-body simulations

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Research in Astronomy and Astrophysics 2021年第1期21卷 25-32页

作者： qiao Wang Key Laboratory for Computational Astrophysics National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

We investigate a hybrid numerical algorithm aimed at large-scale cosmological N-body simulation for on-going and future high precision sky surveys.It makes use of a truncated Fast Multiple Method(FMM)for short-range gravity,incorporating a Particle Mesh(PM)method for long-range potential,which is applied to deal with extremely large particle number.In this work,we present a specific strategy to modify a conventional FMM by a Gaussian shaped factor and provide quantitative expressions for the interaction kernels between multipole expansions.Moreover,a proper Multipole Acceptance Criterion for the hybrid method is introduced to solve potential precision loss induced by the truncation.Such procedures reduce the amount of computation compared to an original FMM and decouple the global communication.A simplified version of code is introduced to verify the hybrid algorithm,accuracy and parallel implementation.

关键词： methods:numerical cosmology:theory large-scale structure of universe

裂后沉降期碳酸盐岩缓坡沉积响应及成储特征——以塔里木盆地下寒武统肖尔布拉克组为例

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沉积学报 2019年第5期37卷 1044-1057页

作者：朱永进倪新锋刘玲利乔占峰陈永权郑剑锋中国石油杭州地质研究院杭州310023 中国石油天然气集团公司碳酸盐岩储层重点实验室杭州310023 中国石油勘探开发研究院北京100083 中国石油塔里木油田分公司新疆库尔勒841000

裂后充填阶段的碳酸盐岩缓坡沉积已逐渐成为深层油气勘探的重点领域之一.以塔里木盆地下寒武统肖尔布拉克组为例,基于最新拼接处理42条二维地震大测线、柯坪地区9个剖面点及12口完钻井测井及取芯等资料,系统开展了其沉积前古构造格局及... 详细信息

裂后充填阶段的碳酸盐岩缓坡沉积已逐渐成为深层油气勘探的重点领域之一.以塔里木盆地下寒武统肖尔布拉克组为例,基于最新拼接处理42条二维地震大测线、柯坪地区9个剖面点及12口完钻井测井及取芯等资料,系统开展了其沉积前古构造格局及岩相古地理响应特征、储层宏观分布与内部结构差异等研究.结果表明:1)沉积期盆内发育"三隆两洼"古构造格局,对肖尔布拉克期碳酸盐岩缓坡体系(组合)内部分异产生明显控制作用,高能颗粒滩及丘滩带分布在古隆起周缘,古洋流进一步复杂化了沉积物构成,划分出塔西南古隆起北缘颗粒滩为主的坡坪式缓坡、柯坪—温宿低隆起丘滩复合体均斜型缓坡、轮南—牙哈低隆起丘滩复合体孤岛型缓坡;2)古隆起周缘中缓坡高能相带构成了肖尔布拉克组储层发育的重要载体,早期云化作用有效保存了原始孔隙,埋藏期以先期孔隙为基础进一步调整改造,预测规模储层主要分布于三大古(低)隆区周缘高能丘滩带内,面积达9×10^4 km^2.不同类型缓坡体系的储层差异明显,其中坡坪式缓坡的颗粒滩储层以Ⅱ类储层为主、分布稳定为特点,最具规模性,可作为下一步油气勘探的重点关注区带.基于实例解剖认为,裂后沉降期碳酸盐岩缓坡体系分异具明显受构造控制特点,深化沉积前古构造格局认识是预测有利储集相带的关键,直接影响后续规模储层预测及品质评价.

关键词：裂后沉降期缓坡规模储层肖尔布拉克组塔里木盆地

Consortium Chain Consensus Vulnerability and Chain Generation Mechanism

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Computers, Materials & Continua 2023年第11期77卷 2505-2527页

作者： Rui qiao hi Dong School of Computer Science and Technology Zhoukou Normal UniversityZhoukou466001China

Effectively identifying and preventing the threat of Byzantine nodes to the security of distributed systems is a challenge in applying consortium chains.Therefore,this paper proposes a new consortium chain generation model,deeply analyzes the vulnerability of the consortium chain consensus based on the behavior of the nodes,and points out the effects of Byzantine node proportion and node state verification on the consensus process and system security.Furthermore,the normalized verification node aggregation index that represents the consensus ability of the consortium organization and the trust evaluation function of the verification node set is derived.When either of the two is lower than the threshold,the consortium institution or the verification node set members are dynamically adjusted.On this basis,an innovative consortium chain generation mechanism based on the Asynchronous Binary Byzantine Consensus Mechanism(ABBCM)is proposed.Based on the extended consortium chain consensus mechanism,a certain consensus value set can be combined into multiple proposals,which can realize crossdomain asynchronous message passing between multi-consortium chains without reducing the system’s security.In addition,experiments are carried out under four classical Byzantine Attack(BA)behaviors,BA1 to BA4.The results show that the proposed method can obtain better delay than the classical random Byzantine consensus algorithm Coin,effectively improving the consensus efficiency based on asynchronous message passing in the consortium chain and thus meeting the throughput of most Internet of Things(IoT)applications.

关键词： Consortium chain Byzantine consensus generation mechanism Internet of Things consensus vulnerability