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建筑工程施工机器人现状分析、应用实例及发展探究
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作者 孟庆禹 陈越 +2 位作者 杨柳溪 臧博文 于航 《产业科技创新》 2024年第5期44-49,共6页
本文梳理了我国建筑机器人的迫切需求,总结了国内建筑机器人面临的诸多障碍,分析了国外建筑机器人发展的3个阶段,对北京市大兴区某4万平方米地下车库工程中使用的“振捣、抹平、抹光”机器人全过程协同流水作业模式进行了深度分析,并为... 本文梳理了我国建筑机器人的迫切需求,总结了国内建筑机器人面临的诸多障碍,分析了国外建筑机器人发展的3个阶段,对北京市大兴区某4万平方米地下车库工程中使用的“振捣、抹平、抹光”机器人全过程协同流水作业模式进行了深度分析,并为未来建筑机器人发展提出可行性建议。 展开更多
关键词 建筑机器人技术 施工阶段 发展建议 人机协作
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基于人工智能的科研管理模式探讨
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作者 陈越 孟庆禹 +2 位作者 侯兴旺 李京洋 于航 《产业科技创新》 2024年第3期83-86,共4页
人工智能技术的蓬勃发展为科研管理模式变革带来新的契机,本文在分析了现有科研管理模式面向人工智能转型过程中面临的3个主要问题的基础上,对基于人工智能的科研管理新范式展开探讨,并从政策体系的建立、科研管理人员的培养以及隐私安... 人工智能技术的蓬勃发展为科研管理模式变革带来新的契机,本文在分析了现有科研管理模式面向人工智能转型过程中面临的3个主要问题的基础上,对基于人工智能的科研管理新范式展开探讨,并从政策体系的建立、科研管理人员的培养以及隐私安全和科技伦理等方面为促进人工智能赋能科研管理等提出相关对策建议。 展开更多
关键词 科研管理 人工智能 体制改革 科研管理决策
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Research on the Freezing Phenomenon of Quantum Correlation by Machine Learning 被引量:3
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作者 Xiaoyu Li Qinsheng Zhu +6 位作者 Yiming Huang Yong Hu qingyu meng Chenjing Su Qing Yang Shaoyi Wu Xusheng Liu 《Computers, Materials & Continua》 SCIE EI 2020年第12期2143-2151,共9页
Quantum correlation shows a fascinating nature of quantum mechanics and plays an important role in some physics topics,especially in the field of quantum information.Quantum correlations of the composite system can be... Quantum correlation shows a fascinating nature of quantum mechanics and plays an important role in some physics topics,especially in the field of quantum information.Quantum correlations of the composite system can be quantified by resorting to geometric or entropy methods,and all these quantification methods exhibit the peculiar freezing phenomenon.The challenge is to find the characteristics of the quantum states that generate the freezing phenomenon,rather than only study the conditions which generate this phenomenon under a certain quantum system.In essence,this is a classification problem.Machine learning has become an effective method for researchers to study classification and feature generation.In this work,we prove that the machine learning can solve the problem of X form quantum states,which is a problem of physical significance.Subsequently,we apply the density-based spatial clustering of applications with noise(DBSCAN)algorithm and the decision tree to divide quantum states into two different groups.Our goal is to classify the quantum correlations of quantum states into two classes:one is the quantum correlation with freezing phenomenon for both Rènyi discord(α=2)and the geometric discord(Bures distance),the other is the quantum correlation of non-freezing phenomenon.The results demonstrate that the machine learning method has reasonable performance in quantum correlation research. 展开更多
关键词 Machine learning quantum correlation freezing phenomenon Rènyi discord geometric discord
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An Immunization Scheme for Ransomware
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作者 Jingping Song qingyu meng +2 位作者 Chenke Luo Nitin Naik Jian Xu 《Computers, Materials & Continua》 SCIE EI 2020年第8期1051-1061,共11页
In recent years,as the popularity of anonymous currencies such as Bitcoin has made the tracking of ransomware attackers more difficult,the amount of ransomware attacks against personal computers and enterprise product... In recent years,as the popularity of anonymous currencies such as Bitcoin has made the tracking of ransomware attackers more difficult,the amount of ransomware attacks against personal computers and enterprise production servers is increasing rapidly.The ransomware has a wide range of influence and spreads all over the world.It is affecting many industries including internet,education,medical care,traditional industry,etc.This paper uses the idea of virus immunity to design an immunization solution for ransomware viruses to solve the problems of traditional ransomware defense methods(such as anti-virus software,firewalls,etc.),which cannot meet the requirements of rapid detection and immediate prevention of new outbreaks attacks.Our scheme includes two parts:server and client.The server provides an immune configuration file and configuration file management functions,including a configuration file module,a cryptography algorithm module,and a display module.The client obtains the immunization configuration file from server in real time,and performs the corresponding operations according to the configuration file to make the computer have an immune function for a specific ransomware,including an update module,a configuration file module,a cryptography algorithm module,a control module,and a log module.This scheme controls mutexes,services,files and registries respectively,to destroy the triggering conditions of the virus and finally achieve the purpose of immunizing a computer from a specific ransomware. 展开更多
关键词 MALWARE ransomware malware immunization
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Optical properties of NaY(MoO4)2:Eu3+ nanophosphors prepared by molten salt method 被引量:10
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作者 Lin Bai qingyu meng +1 位作者 Mingxue Huo Yu Sui 《Journal of Rare Earths》 SCIE EI CAS CSCD 2019年第12期1261-1268,共8页
We synthesized NaY(MoO4)2:Eu3+phosphors of different doping concentrations by a molten salt method.This facile way possesses advantages such as simple process,lower calcination temperature(350℃)and small particle siz... We synthesized NaY(MoO4)2:Eu3+phosphors of different doping concentrations by a molten salt method.This facile way possesses advantages such as simple process,lower calcination temperature(350℃)and small particle size(70 nm).The crystal system is tetragonal phase and crystal lattice is body centered.The photo luminescence measurements including emission spectra,excitation spectra and fluorescence decay curves were carried out,elucidating that NaY(MoO4)2:Eu3+can be effectively excited by near UV and blue light.Moreover,it can be concluded that Eu3+energy transfer type is exchange interaction.Huang-Rhys factor and the critical energy transfer distance(Rc)were calculated to be 0.043 and 0.995 nm,respectively.Auzel’s model was used to obtain the intrinsic radiative transition lifetime of5 D0 level(τ0=0.923 ms).Furthermore,a calculation method was used to calculate refractive index n of nontransparent NaY(MoO4)2:1 mol%Eu3+phosphor,and n was obtained to be 1.86. 展开更多
关键词 Energy transfer Red PHOSPHORS EU^3+ MOLYBDATES Rare earths
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Modelling of grinding mechanics:A review 被引量:7
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作者 qingyu meng Bing GUO +4 位作者 Qingliang ZHAO Hao Nan LI Mark JJACKSON Barbara SLINKE Xichun LUO 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第7期25-39,共15页
Grinding is one of the most widely used material removal methods at the end of many process chains.Grinding force is related to almost all grinding parameters,which has a great influence on material removal rate,dimen... Grinding is one of the most widely used material removal methods at the end of many process chains.Grinding force is related to almost all grinding parameters,which has a great influence on material removal rate,dimensional and shape accuracy,surface and subsurface integrity,thermodynamics,dynamics,wheel durability,and machining system deformation.Considering that grinding force is related to almost all grinding parameters,grinding force can be used to detect grinding wheel wear,energy calculation,chatter suppression,force control and grinding process simulation.Accurate prediction of grinding forces is important for optimizing grinding parameters and the structure of grinding machines and fixtures.Although there are substantial research papers on grinding mechanics,a comprehensive review on the modeling of grinding mechanics is still absent from the literature.To fill this gap,this work reviews and introduces theoretical methods and applications of mechanics in grinding from the aspects of modeling principles,limitations and possible future trendencies. 展开更多
关键词 Force modeling GRINDING Grinding mechanics Macro force Micro force Model application
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FRMD7基因新突变位点导致先天性眼球震颤一家系的遗传学研究
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作者 付皓丽 张成 +9 位作者 梁舒婷 苗泽群 孟庆娱 黄旅珍 郭丽莉 欧阳倩如 许欣 曹宇 张晶议 王乐今 《中华眼科医学杂志(电子版)》 2022年第3期152-157,共6页
目的探讨4.1埃兹蛋白-根蛋白-膜突蛋白结构域包含的7(FRMD7)基因新突变位点导致先天性眼球震颤(CN)一家系的遗传学特征。方法2021年10月,收集于北京大学人民医院眼视光中心确诊CN家系四代19例的临床资料。采集家系中3例CN患者和9例眼正... 目的探讨4.1埃兹蛋白-根蛋白-膜突蛋白结构域包含的7(FRMD7)基因新突变位点导致先天性眼球震颤(CN)一家系的遗传学特征。方法2021年10月,收集于北京大学人民医院眼视光中心确诊CN家系四代19例的临床资料。采集家系中3例CN患者和9例眼正常者的外周血样本,检查受试者的最佳矫正视力(BCVA)、眼前节及眼底;评估眼球震颤的类型、头位、是否有中间带及眼位等。应用GenCap液相仪抓取目标基因技术,获取与眼部疾病相关的811个基因的外显子区域及其侧翼区域,对先证者进行高通量测序,筛选出致病基因和突变位点,并在家系中进行Sanger测序和共分离验证。使用Mutation Taster软件分析突变位点的基因突变类型;预测突变型蛋白质的三维结构和功能改变。结果该家系的先证者(Ⅲ6)男性,11岁。此患者右眼BCVA 0.7,左眼BCVA 0.8。先证者表弟(Ⅲ9)男性,2岁,双眼视力检查配合度不佳。先证者祖父(Ⅰ1)男性,73岁。此患者右眼BCVA 0.3,左眼BCVA 0.4,双眼晶状体混浊。3患者均双眼正位,眼球震颤呈水平钟摆型,无中间带及代偿头位,眼底检查未见明显异常。此家系患者均为男性,呈现隔代遗传特征,符合X连锁隐性遗传。家系中12例受试者外周血基因检测结果显示,3例患者FRMD7基因第9外显子编码区发生半合子变异,Ⅱ6、Ⅱ8及Ⅲ8等3例眼正常女性者在该区域发生杂合变异,核苷酸变异c.822C>A,氨基酸变异p.Y274X,使终止密码子提前出现,造成蛋白质编码提前终止,大量氨基酸丢失。根据美国医学遗传学与基因组学学会遗传变异分类标准与指南,该变异被评定为疑似致病性变异。经Mutation Taster软件分析,结果显示突变性质为无义突变;突变型蛋白质三维结构和功能的预测显示该突变影响FRMD7蛋白结构的稳定性,可能使其功能受损。结论FRMD7基因核苷酸变异c.822C>A(p.Y274X)为无义突变,属于新突变位点,此变异是该家系CN的可能致病原因,扩大了FRMD7基因突变频谱。 展开更多
关键词 先天性眼球震颤 X性染色体隐性遗传 FRMD7基因 基因突变
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税率不确定性与企业投资决策 被引量:3
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作者 孟庆玉 郑登津 袁淳 《中国会计评论》 2020年第3期491-522,共32页
已有文献主要考察税率变动和税率本身高低对企业投资决策活动的影响,鲜有文献研究税率不确定性对投资行为的影响。鉴于我国各地税收优惠政策及税收征管强度的差异和变化使得公司的税率存在较大的不确定性,探讨中国的税率不确定性对投资... 已有文献主要考察税率变动和税率本身高低对企业投资决策活动的影响,鲜有文献研究税率不确定性对投资行为的影响。鉴于我国各地税收优惠政策及税收征管强度的差异和变化使得公司的税率存在较大的不确定性,探讨中国的税率不确定性对投资决策的影响显得尤为重要。本文研究发现:税率不确定性越大,公司投资支出降低得越明显,而且显著抑制过度投资行为。进一步地,当公司上一期的税率处于波峰、融资约束较高时,这种抑制作用更加显著;而政府补助、产业政策优惠则会弱化这种负相关关系。本文结论补充和拓展了以往关于投资理论的研究,不仅对企业的投资决策和政府部门的税收管理具有重要参考意义,也响应了中共十九大关于深化投资改革和税收制度改革的精神。 展开更多
关键词 税率不确定性 投资支出 投资效率
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The critical role of m^(6)A methylation in the pathogenesis of Graves'ophthalmopathy 被引量:3
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作者 Li Zhu Siyan Li +12 位作者 Shikun He Qizhe Tong Lejin Wang Xiaohua Li Xi Wu qingyu meng Enzhong Jin Chuan Zhang Tianyuan Li Ningda Xu Lvzhen Huang Yi Wang Mingwei Zhao 《Eye and Vision》 SCIE CSCD 2020年第1期543-552,共10页
Purpose:To investigate the role of N6-methyladenosine(m^(6)A)RNA modification in the pathogenesis of Graves'ophthalmopathy(GO).Methods:Surgically excised extraocular muscles from 7 patients with GO and 5 subjects ... Purpose:To investigate the role of N6-methyladenosine(m^(6)A)RNA modification in the pathogenesis of Graves'ophthalmopathy(GO).Methods:Surgically excised extraocular muscles from 7 patients with GO and 5 subjects without GO were used.The global m^(6)A levels in the specimens were determined using an m^(6)A RNA methylation quantification kit.RNA sequencing(RNA-seq)was used to analyze the molecules involved in the regulation of m^(6)A RNA methylation and the differential expression of mRNAs between the two groups(4 eyes,respectively).The expression of m^(6)A RNA modification genes was evaluated by real-time PCR.The functional implications of the gene alterations between the GO and control specimens were determined by Gene Ontology analysis.Results:The m^(6)A level was significantly increased in the specimens of GO patients compared to the control specimens(P<0.05).The expression of m^(6)A methylation regulators,such as WT1 associated protein(WTAP),alkylation repair homolog protein 5(ALKBH5),E74 like ETS transcription factor 3(ELF3),YTH N6-methyladenosine RNA binding protein 2(YTHDF2),YTHDF3 and YTH domain containing 2(YTHDC2),was significantly upregulated(P<0.05).Gene Ontology enrichment analysis showed that the most highly upregulated genes and biological pathways were related to the immune response and inflammatory processes such as lymphocyte activation,leukocyte differentiation,cytokine production and cytokine-mediated signaling pathways.Conclusions:Our results suggest that m^(6)A methylation may play a critical role in the pathogenesis of GO and that targeting genes that regulate m^(6)A methylation may provide a new therapeutic approach for GO. 展开更多
关键词 m^(6)A methylation Graves'ophthalmopathy PATHOGENESIS RNA-seq
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微创改良手术矫正间歇性外斜视的临床研究
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作者 许欣 郭丽莉 +8 位作者 苗泽群 欧阳倩如 张晶议 李岩 孟庆娱 梁舒婷 付皓丽 曹宇 王乐今 《中华眼科医学杂志(电子版)》 2021年第6期327-332,共6页
目的探讨微创单眼外直肌后徙联合内直肌缩短术(R&R)治疗基本型及集合不足型间歇性外斜的临床疗效。方法选取2018年3月至2020年8月于北京大学人民医院眼科就诊且进行了微创单眼外直肌后徙联合内直肌缩短术的间歇性外斜视患者113例(11... 目的探讨微创单眼外直肌后徙联合内直肌缩短术(R&R)治疗基本型及集合不足型间歇性外斜的临床疗效。方法选取2018年3月至2020年8月于北京大学人民医院眼科就诊且进行了微创单眼外直肌后徙联合内直肌缩短术的间歇性外斜视患者113例(113只眼)进行研究。其中,男性48例(48只眼),女性65例(65只眼),年龄3~18岁,平均年龄(8.1±3.1)岁。手术前对所有患者进行睫状肌麻痹下验光,根据年龄及屈光状态予以处方配镜,在屈光矫正的前提下检查患者远、近斜视度。根据远、近斜视度之间的关系选择基本型及集合不足型间歇性外斜视患者行微创手术,关键步骤是彻底分离节制韧带及肌间膜,减少眼外肌周围组织粘连。随访6个月以上。手术前后,以近立体视锐度图检查患者近立体视功能,以同视机检查开散性融合功能、集合性融合功能、融合范围、远立体视功能。年龄、病程、斜视度、融合范围、集合性融合及开散性融合等行正态性检验,符合正态分布的连续变量采用x±s描述,其手术前后的比较采用配对t检验。性别、近立体视功能及远立体视功能等采用例数及百分比描述。手术前后立体视功能的有无采用卡方检验。结果本研究纳入113例(113只眼)患者,平均随访时间0.749年,最短随访6个月,最长随访时间3.5年,根据最后一次随访病例的记录,眼位保持正位的患者有97例(+4 PD~-8 PD),过矫3例(+6 PD~+8 PD),欠矫13例(-10 PD~-20 PD);正位率、欠矫率及过矫率分别为85.8%、2.7%及11.5%。融合范围均值术前为(14.61±8.43)°,术后为(22.70±5.72)°,两者差异具有统计学意义(t=-9.726,P<0.05)。有77例患者近立体视锐度值在最后一次随访中达到了40″,占68.1%;有10例患者术前无近立体视的患者在手术后获得近立体视,近立体视锐度值均能保持在40″至200″范围内,占8.8%。在最后一次复诊中,有68例患者的近立体视功能较前改善,术前范围200″~800″,术后范围60″~400″,占60.18%。有85例患者的远立体视功能有改善,术前范围40″~800″,术后范围40″~400″,占76.6%;有47例患者由无远立体视变为有远立体视,范围60″~800″,占42.3%。手术前后远立体视的有无经χ2检验,其差异无统计学意义(χ2=1.826,P>0.05)。结论微创外直肌后徙联合内直肌缩短术治疗基本型及集合不足型间歇性外斜视手术成功率高,术后患者双眼视功能恢复较好,可作为治疗基本型及集合不足型间歇性外斜视的优选方案。 展开更多
关键词 间歇性外斜视 手术治疗 立体视 融合功能
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Sorption phenomena of PCBs in environment
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作者 qingyu meng Shaogang Chu Xiaobai Xu 《Chinese Science Bulletin》 SCIE EI CAS 2001年第2期89-97,共9页
The relationship between the properties of PCBs and the behavior of soil and sediment is reviewed. The sorp-tion phenomena of PCBs in the environment are described with different models. The research progress on the s... The relationship between the properties of PCBs and the behavior of soil and sediment is reviewed. The sorp-tion phenomena of PCBs in the environment are described with different models. The research progress on the sorption mechanisms is also discussed. 展开更多
关键词 PCBS SORPTION ENVIRONMENTAL transport.
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Design and Implementation of Key-Value Database for Ship Virtual Test Platform Based on Distributed System
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作者 Kejia Zhang qingyu meng +2 位作者 Haiwei Pan Maocai Yuan Baoying Ma 《国际计算机前沿大会会议论文集》 EI 2023年第1期109-123,共15页
The virtual test platform is a vital tool for ship simulation and testing.However,the numerical pool ship virtual test platform is a complex system that comprises multiple heterogeneous data types,such as relational d... The virtual test platform is a vital tool for ship simulation and testing.However,the numerical pool ship virtual test platform is a complex system that comprises multiple heterogeneous data types,such as relational data,files,text,images,and animations.The analysis,evaluation,and decision-making processes heavily depend on data,which continue to increase in size and complexity.As a result,there is an increasing need for a distributed database system to manage these data.In this paper,we propose a Key-Value database based on a distributed system that can operate on any type of data,regardless of its size or type.This database architecture supports class column storage and load balancing and optimizes the efficiency of I/O bandwidth and CPU resource utilization.Moreover,it is specif-ically designed to handle the storage and access of largefiles.Additionally,we propose a multimodal data fusion mechanism that can connect various descrip-tions of the same substance,enabling the fusion and retrieval of heterogeneous multimodal data to facilitate data analysis.Our approach focuses on indexing and storage,and we compare our solution with Redis,MongoDB,and MySQL through experiments.We demonstrate the performance,scalability,and reliability of our proposed database system while also analysing its architecture’s defects and providing optimization solutions and future research directions.In conclu-sion,our database system provides an efficient and reliable solution for the data management of the virtual test platform of numerical pool ships. 展开更多
关键词 Key-Value databases multimodal data fusion heterogeneous data distributed systems columnar-like storage INDEXING
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