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Automatic modelling of urban subsurface with ground-penetrating radar using multi-agent classification method

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Geo-Spatial Information Science 2022年第4期25卷 588-599页

作者： Tess Xianghuan Luo pengpeng yuan Song Zhu Guangdong Key Laboratory of Urban Informatics Shenzhen UniversityShenzhenChina Department of Land Surveying and Geo-informatics The Hong Kong Polytechnic UniversityHong KongChina College of Civil and Transportation Engineering Shenzhen UniversityShenzhenChina

The subsurface of urban cities is becoming increasingly congested.In-time records of subsur-face structures are of vital importance for the maintenance and management of urban infrastructure beneath or above the ground.Ground-penetrating radar(GPR)is a nondestructive testing method that can survey and image the subsurface without excava-tion.However,the interpretation of GPR relies on the operator’s experience.An automatic workflow was proposed for recognizing and classifying subsurface structures with GPR using computer vision and machine learning techniques.The workflow comprises three stages:first,full-cover GPR measurements are processed to form the C-scans;second,the abnormal areas are extracted from the full-cover C-scans with coefficient of variation-active contour model(CV-ACM);finally,the extracted segments are recognized and classified from the corresponding B-scans with aggregate channel feature(ACF)to produce a semantic map.The selected computer vision methods were validated by a controlled test in the laboratory,and the entire workflow was evaluated with a real,on-site case study.The results of the controlled and on-site case were both promising.This study establishes the necessity of a full-cover 3D GPR survey,illustrating the feasibility of integrating advanced computer vision techniques to analyze a large amount of 3D GPR survey data,and paves the way for automating subsurface modeling with GPR.

关键词： Subsurface modeling ground-penetrating radar computer vision active contour model aggregate channel feature

基于探地雷达与激光雷达的隧洞衬砌内外一体化诊断

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吉林水利 2024年第7期 53-57页

作者：周瑜叶爽周延峰元鹏鹏深圳市华章检测技术有限公司广东深圳518127 深圳大学土木与交通工程学院广东深圳518060

针对输水隧洞检修天窗短、病害多、安全风险大的问题,本研究提出了一种结合探地雷达(GPR)和激光扫描(LiDAR)内外一体化的方法诊断隧洞衬砌。首先,利用LiDAR快速扫描衬砌表面,定位表面的裂缝和渗漏;而后对隧洞衬砌内部进行GPR探测,对异... 详细信息

针对输水隧洞检修天窗短、病害多、安全风险大的问题,本研究提出了一种结合探地雷达(GPR)和激光扫描(LiDAR)内外一体化的方法诊断隧洞衬砌。首先,利用LiDAR快速扫描衬砌表面,定位表面的裂缝和渗漏;而后对隧洞衬砌内部进行GPR探测,对异常区域内部是否存在分离或空洞进行成像和验证;最后,统一衬砌内外病害时空编码,联合内外病害诊断,定位危害大的发育性病害,为精确运维提供可靠依据。本研究以深圳市龙岗区某疏水隧洞为案例,检测结果表明GPR和LiDAR在病害位置、大小和严重程度方面存在一致性,证明了衬砌内外综合诊断的可行性。同时,当GPR和LiDAR检测出同一缺陷时,证明该处缺陷严重,需要进行适当维护。

关键词：输水隧洞探地雷达激光雷达衬砌检测

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Machine Learning based Optical Proximity Correction Techniques

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Journal of Microelectronic Manufacturing 2020年第4期3卷 59-68页

作者： pengpeng yuan Taian Fan Yaobin Feng Peng Xu Yayi Wei Institute of Microelectronics Chinese Academy of ScienceBeijingChina100029 University of Chinese Academy of Science BeijingChina100029 Yangtze Memory Technologies Co. LtdWuhanHubeiChina430000

The shrinking of the size of the advanced technological nodes brings up new challenges to the semiconductor manufacturing community.The optical proximity correction(OPC)is invented to reduce the errors of the lithographic process.The conventional OPC techniques rely on the empirical models and optimization methods of iterative type.Both the accuracy and computing speed of the existing OPC techniques need to be improved to fulfill the stringent requirement of the research and design for latest technological nodes.The emergence of machine learning technologies inspires novel OPC algorithms.More accurate forward simulation of the lithographic process and single turn optimization methods are enabled by the machine learning based OPC techniques.We discuss the latest progress made by the OPC community in the process simulation and optimization based on machine learning techniques.

关键词： Optical Proximity Correction Machine Learning Deep Learning Lithography

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狭小空间内宽扁梁结构增大截面加固施工技术

山西建筑 2024年第10期50卷 113-116页

作者：丁传奇李跃孟君袁鹏鹏李福众北京建工集团有限责任公司北京100055

针对既有建筑梁截面增大施工中出现的施工作业空间狭小、综合管线排布复杂且拆除困难、新老混凝土结合处易错台、凿除多余混凝土等施工技术难题,通过分析增大截面法施工工艺,提出优化设计箍筋布置、模板支撑体系、灌浆材料和灌注施工工... 详细信息

针对既有建筑梁截面增大施工中出现的施工作业空间狭小、综合管线排布复杂且拆除困难、新老混凝土结合处易错台、凿除多余混凝土等施工技术难题,通过分析增大截面法施工工艺,提出优化设计箍筋布置、模板支撑体系、灌浆材料和灌注施工工艺,并结合连通器的原理,提出利用一种灌浆料辅助装置,有效地实现了灌浆料的顺利灌注,保证了灌浆过程的质量控制,可为增大截面法施工技术提供技术参考。

关键词：狭小空间宽扁梁增大截面法辅助装置

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Large-Scale and Reversible Synthesis of Bright Upconversion Crystals with Almost 100%Yield by a Minimalist Method for Recyclable Application

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CCS Chemistry 2024年第6期6卷 1512-1522页

作者： pengpeng Lei yuan Liang Pengye Du Yong Zhang Hongjie Zhang State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022 University of Science and Technology of China Hefei 230026 Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou 341000 Department of Biomedical Engineering Faculty of EngineeringNational University of SingaporeSingapore 117583 Department of Chemistry Tsinghua UniversityBeijing 100084

Upconversion luminescence(UCL)materials have the potential for many applications due to their unique optical properties.Some technical challenges such as complex synthesis with low yield and nondegradability need to be addressed for practical use.Here,we report for the first time a minimalist method for large-scale synthesis of Cs_(2)NaErCl_(6)UCL crystals with almost 100%yield,simply by dissolving metal chlorides in water and then drying,referred to as the“dissolve-dry”method.Cs_(2)NaErCl_(6)crystals produced under such mild conditions exhibited bright UCL at either 808 or 980 nm irradiation.UCL was achieved through an excited state absorption process,and the excellent performance was mainly attributed to the large unit cells of the crystals and the long lifetime of Er^(3+)excited energy levels.Moreover,the synthesis was reversible and could be scaled up unlimitedly,making it suitable for industrial applications,with recyclable products.The recyclable application of Cs_(2)NaErCl_(6)crystals as a luminescent medium in near-infrared light-emitting diode excitable upconversion devices was demonstrated based on its excellent recyclability.Our work not only provides a new strategy for large-scale synthesis of UCL crystals but also demonstrates the recyclability of this material and its related applications.

关键词： rare earth upconversion reversible synthesis minimalist method application

Rational design of unrestricted pRN1 derivatives and their application in the construction of a dual plasmid vector system for Saccharolobus islandicus

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mLife 2024年第1期3卷 119-128页

作者： pengpeng Zhao Xiaonan Bi Xiaoning Wang Xu Feng Yulong Shen Guanhua yuan Qunxin She CRISPR and Archaea Biology Research Center State Key Laboratory of Microbial Technology and Microbial Technology InstituteShandong UniversityQingdaoChina

Saccharolobus islandicus REY15A represents one of the very few archaeal models with versatile genetic tools,which include efficient genome editing,gene silencing,and robust protein expression systems.However,plasmid vectors constructed for this crenarchaeon thus far are based solely on the pRN2 cryptic plasmid.Although this plasmid coexists with pRN1 in its original host,early attempts to test pRN1-based vectors consistently failed to yield any stable host-vector system for Sa.islandicus.We hypothesized that this failure could be due to the occurrence of CRISPR immunity against pRN1 in this archaeon.We identified a putative target sequence in orf904 encoding a putative replicase on pRN1(target N1).Mutated targets(N1a,N1b,and N1c)were then designed and tested for their capability to escape the host CRISPR immunity by using a plasmid inter-ference assay.The results revealed that the original target triggered CRISPR immunity in this archaeon,whereas all three mutated targets did not,indicating that all the designed target mutations evaded host immunity.These mutated targets were then incorporated into orf904 individually,yielding corresponding mutated pRN1 backbones with which shuttle plasmids were constructed(pN1aSD,pN1bSD,and pN1cSD).Sa.islandicus transformation revealed that pN1aSD and pN1bSD were functional shuttle vectors,but pN1cSD lost the capability for replication.These results indicate that the missense mutations in the conserved helicase domain in pN1c inactivated the replicase.We further showed that pRN1-based and pRN2-based vectors were stably maintained in the archaeal cells either alone or in combination,and this yielded a dual plasmid system for genetic study with this important archaeal model.

关键词： archaeal genetics CRISPR-Cas CRISPR escape mutations dual plasmid vectors Saccharolobus-E.coli shuttle vectors

基于“动态”宏观调控视角的货币政策模式对比研究

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金融理论探索 2023年第4期 20-30页

作者：张龙袁鹏鹏暨南大学经济学院广东广州510632 广发银行总行广东广州510062

在规则性货币政策占领历史舞台数十年后,近来相机抉择货币政策在各国央行中出现抬头现象,说明相机抉择和规则性货币政策的相对有效性具有动态性,以往基于不变参数模型研究的相机抉择和规则性货币政策的长期不变有效性严重缺乏实际经济... 详细信息

在规则性货币政策占领历史舞台数十年后,近来相机抉择货币政策在各国央行中出现抬头现象,说明相机抉择和规则性货币政策的相对有效性具有动态性,以往基于不变参数模型研究的相机抉择和规则性货币政策的长期不变有效性严重缺乏实际经济意义。基于此,本文构建了时变参数结构模型,并基于“动态”宏观调控的视角数值模拟了不同经济状态下相机抉择和规则性货币政策的动态有效性。研究结果发现:第一,总需求冲击在经济高涨时期影响较大,规则性货币政策更有效;在经济萧条时期影响较小,相机抉择货币政策更有效;第二,总供给冲击无论在经济高涨时期还是经济萧条时期都会带来产出和通货膨胀调控的两难选择,但规则性货币政策在经济高涨时期相对更能有效应对总供给冲击,相机抉择货币政策在经济萧条时期相对更能有效应对总供给冲击。随着我国进入经济新常态时期,量化宽松的相机抉择货币政策将是中国央行未来一段时间的较好选择。

关键词：宏观调控货币政策相机抉择规则性货币政策

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基于信令数据的中型城市通勤公交站点优化方法

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交通信息与安全 2024年第1期42卷 142-149页

作者：葛浩菁吕远焦朋朋北京建筑大学通用航空技术北京实验室北京100044

大中型城市之间的手机通信基站密度和通勤出行结构不同,公交站点布设呈现出显著差异。在此背景下,研究了基于改进Mean Shift聚类算法的中型城市通勤公交站点优化方法。该方法采用荆州市中心城区信令数据中的通勤记录,以系统总成本(包括... 详细信息

大中型城市之间的手机通信基站密度和通勤出行结构不同,公交站点布设呈现出显著差异。在此背景下,研究了基于改进Mean Shift聚类算法的中型城市通勤公交站点优化方法。该方法采用荆州市中心城区信令数据中的通勤记录,以系统总成本(包括运营成本和乘客步行时间成本)作为主要评价指标。根据中心城区早高峰的通勤出行需求,制定通勤公交站点优化方案。通过对比优化结果和现有公交站点布局,验证了优化方法的有效性;比较不同聚类算法,证明改进的Mean Shift聚类算法的性能优越性;考虑基站和等时圈的影响,对比不同场景,证明了考虑二者影响的必要性。结果表明:①针对荆州市研究区域的早高峰出行需求,优化方法共设置28个公交站,乘客步行时间成本下降51.98%,系统总成本下降17.82%,表明本方法能够得到系统总成本更优的站点布设方案,有效减少研究区域内乘客步行时间成本;②与不同聚类算法的比较中,改进Mean Shift算法得到的方案有明显提升,系统总成本比K-means聚类算法下降8.73%,比近邻传播聚类算法(affinity propagation,AP)下降2.48%;③与未考虑基站和等时圈影响的情况相比,本算法步行时间成本有所下降。上述指标表明改进Mean Shift聚类方法在聚类质量上优于其他方法,可以获得更优的公交站点布设方案,为中型城市的公交线路规划提供基础。

关键词：交通规划中型城市公交站点布设改进Mean Shift算法信令数据

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元代地方经费承担主体社会化与基层治理——以地方官廨兴修为中心的考察

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求索 2024年第1期 159-168页

作者：孙朋朋河南大学黄河文明与可持续发展研究中心暨黄河文明省部共建协同创新中心河南开封475001

元朝政权除沿袭前代中央财政集权体制之外,又建构诸多制度以约束地方政府的财权,致使地方政府时常面临财政困窘的局面,乃至于无力主持地方行政设施建设。官廨兴修本是政府的基本职责,然元代地方政府受制于财力不足的现实,有时需仰仗社... 详细信息

元朝政权除沿袭前代中央财政集权体制之外,又建构诸多制度以约束地方政府的财权,致使地方政府时常面临财政困窘的局面,乃至于无力主持地方行政设施建设。官廨兴修本是政府的基本职责,然元代地方政府受制于财力不足的现实,有时需仰仗社会力量来筹措官廨营修所需经费。元代地方政府为降低行政成本,只得寻求经费来源与承担主体的社会化,由此给予了社会力量介入地方政治场域的契机。元代社会力量积极参与并主持行政设施建设,成为政府财政困境下实现地方有效治理的依托群体,此局势促使元代地方决策群体趋向多元化格局。元代地方财政困境下基层政治场域中的官民互动现象,凸显出政府行政体制对财政需求的妥协。

关键词：元代地方财政政治场域官廨基层治理

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