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Compressive Sensing Sparse Sampling Method for Composite Material Based on Principal Component Analysis

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第2期35卷 282-289页

作者： Sun Yajie Gu Feihong ji sai Wang Lihua jiangsu Engineering Centre of Network Monitoring Nanjing University of Information Science and Technology Nanjing 210044 P. R. China jiangsu Collaborative Innovation Center on Atmospheric Environment and Equipment Technology Nanjing University of Information Science and Technology Nanjing 210044 P. R. China School of Computer and Software Nanjing University of Information Science and Technology Nanjing 210044 P. R. China School of Information and Control Nanjing University of Information Science and Technology Nanjing 210014 P. R. China

Signals can be sampled by compressive sensing theory with a much less rate than those by traditional Nyquist sampling theorem,and reconstructed with high probability,only when signals are sparse in the time domain or a transform domain.Most signals are not sparse in real world,but can be expressed in sparse form by some kind of sparse transformation.Commonly used sparse transformations will lose some information,because their transform bases are generally fixed.In this paper,we use principal component analysis for data reduction,and select new variable with low dimension and linearly correlated to the original variable,instead of the original variable with high dimension,thus the useful data of the original signals can be included in the sparse signals after dimensionality reduction with maximize portability.Therefore,the loss of data can be reduced as much as possible,and the efficiency of signal reconstruction can be improved.Finally,the composite material plate is used for the experimental verification.The experimental result shows that the sparse representation of signals based on principal component analysis can reduce signal distortion and improve signal reconstruction efficiency.

关键词： principal component analysis compressive sensing sparse representation signal reconstruction

基于FK-FE混合方法的位错点源作用下全过程结构地震反应模拟

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工程力学 2024年第4期41卷 184-198页

作者：巴振宁鲁世斌付继赛梁建文芦燕中国地震局地震工程综合模拟与城乡抗震韧性重点实验室天津300354 天津大学土木工程系天津300354

基于区域缩减思想,集整基于精确动力刚度矩阵的频率波数域(FK)半解析方法和有限元(FE)数值方法各自优势(FK精确高效模拟一维波速结构地震波传播;FEM具有丰富单元和本构类型,可精细模拟工程结构地震反应),提出了一种从震源到工程结构全... 详细信息

基于区域缩减思想,集整基于精确动力刚度矩阵的频率波数域(FK)半解析方法和有限元(FE)数值方法各自优势(FK精确高效模拟一维波速结构地震波传播;FEM具有丰富单元和本构类型,可精细模拟工程结构地震反应),提出了一种从震源到工程结构全过程地震反应模拟的FK-FE混合方法。并将FK代码作为插件二次开发到大型商业有限元软件ABAQUS中,实现了ABAQUS平台下从震源到工程结构的全过程宽频地震反应物理模拟。验证了FK-FE混合方法正确性,进而将其应用于位错点源作用下美国SAC机构设计的9层Benchmark抗弯钢框架结构全过程0 Hz~15 Hz宽频地震反应模拟,重点探讨了地壳层波速结构和近地表场地条件对框架结构地震反应的影响。研究表明:地壳层速度结构和场地类别对该结构的地震反应均有显著影响,地壳层速度结构3(较硬)相比速度结构1(较软),结构最大位移和层间位移角分别减小了22.7%和62.0%;Ⅱ类场地相较于Ⅳ类场地,结构最大位移和层间位移角分别减小了22.3%和44.7%。

关键词：地震反应位错点源 FK-FE混合方法区域缩减全过程模拟

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BIM技术在城市更新旧改中的应用研究

价值工程 2024年第20期43卷 81-83页

作者：嵇赛克浙江省建科建筑设计院有限公司杭州310000

旧改作为城市更新的关键环节,涉及到建筑、规划、结构、市政等多个专业领域的融合与创新,因此,需要综合运用各种技术,形成技术合力,以助推城市更新的实现。本文以某市老旧小区为例,结合实际情况应用BIM技术,实施功能分析,设计了改进方案... 详细信息

旧改作为城市更新的关键环节,涉及到建筑、规划、结构、市政等多个专业领域的融合与创新,因此,需要综合运用各种技术,形成技术合力,以助推城市更新的实现。本文以某市老旧小区为例,结合实际情况应用BIM技术,实施功能分析,设计了改进方案,并融合多项关键技术。经过评估,小区的整体环境得到了大幅提升,绿色建筑技术的应用使得小区能耗得以降低,节能减排效果显著,小区功能布局更加合理,改造效果显著。

关键词：城市更新旧改建筑设计技术结构加固与改造技术

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Approximation Algorithm for the Balanced 2-Correlation Clustering Problem

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Tsinghua Science and Technology 2022年第5期27卷 777-784页

作者： sai ji Dachuan Xu Donglei Du Ling Gai Zhongrui Zhao Department of Operations Research and Information Engineering Beijing University of TechnologyBeijing 100124China Beijing Institute for Scientific and Engineering Computing Beijing University of TechnologyBeijing 100124China Faculty of Business Administration University of New BrunswickFrederictonNB E3B 5A3Canada Glorious Sun School of Business and Management Donghua UniversityShanghai 200051China

The Correlation Clustering Problem(CorCP) is a significant clustering problem based on the similarity of data.It has significant applications in different fields,such as machine learning,biology,and data mining,and many different problems in other areas.In this paper,the Balanced 2-CorCP(B2-CorCP) is introduced and examined,and a new interesting variant of the CorCP is described.The goal of this clustering problem is to partition the vertex set into two clusters with equal size,such that the number of disagreements is minimized.We first present a polynomial time algorithm for the B2-CorCP on M-positive edge dominant graphs(M≥ 3).Then,we provide a series of numerical experiments,and the results show the effectiveness of our algorithm.

关键词： balanced clustering k-correlation clustering positive edge dominant graphs approximation algorithm

Nitrogen-doped titanium dioxide/schwertmannite nanocomposites as heterogeneous photo-Fenton catalysts with enhanced efficiency for the degradation of bisphenol A

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Journal of Environmental Sciences 2024年第9期143卷 1-11页

作者： Xing-Xing Qiao Yu-Hang Xu Xiang-ji Liu sai-Le Chen Zhou Zhong Ya-Feng Li jian Lü Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation College of Resources and EnvironmentFujian Agriculture and Forestry UniversityFuzhou 350002China State Key Laboratory of Photocatalysis on Energy and Environment Fuzhou UniversityFuzhou 350116China

Potential health risks related to environmental endocrine disruptors(EEDs)have aroused research hotspots at the forefront of water treatment technologies.Herein,nitrogen-doped titanium dioxide/schwertmannite nanocomposites(N-TiO_(2)/SCH)have been successfully developed as heterogeneous catalysts for the degradation of typical EEDs via photo-Fenton processes.Due to the sustainable Fe(Ⅲ)/Fe(Ⅱ)conversion induced by photoelectrons,as-prepared N-TiO_(2)/SCH nanocomposites exhibit much enhanced efficiency for the degradation of bisphenol A(BPA;ca.100% within 60 min under visible irradiation)in a wide pH range of 3.0-7.8,which is significantly higher than that of the pristine schwertmannite(ca.74.5%)or N-TiO_(2)(ca.10.8%).In this photo-Fenton system,the efficient degradation of BPA is mainly attributed to the oxidation by hydroxyl radical(·OH)and singlet oxygen(^(1)O_(2)).Moreover,the possible catalytic mechanisms and reaction pathway of BPA degradation are systematically investigated based on analytical and photoelectrochemical analyses.This work not only provides a feasible means for the development of novel heterogeneous photo-Fenton catalysts,but also lays a theoretical foundation for the potential application of mineral-based materials in wastewater treatment.

关键词： Titanium dioxide Schwertmannite Fenton reaction Environmental endocrine disruptors Photocatalysis

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高原高寒地区应急保障垃圾处置实验

环境科技 2024年第1期37卷 17-21页

作者：胡孙陈纪赛周永贤张永良王小峰中船绿洲环保(南京)有限公司江苏南京211162

为促进我国高原高寒地区应急保障技术及装备高质量发展,实现高原高寒地区灾害现场垃圾及时无害化焚烧处置。依托于公司参与的“十三五”国家重点研发计划科研项目,通过中试实验方法,在海拔3540 m,环境温度-16℃条件下,以格尔木纳赤台为... 详细信息

为促进我国高原高寒地区应急保障技术及装备高质量发展,实现高原高寒地区灾害现场垃圾及时无害化焚烧处置。依托于公司参与的“十三五”国家重点研发计划科研项目,通过中试实验方法,在海拔3540 m,环境温度-16℃条件下,以格尔木纳赤台为实验场地,验证在高原高寒应急条件下移动式垃圾处置系统对现场存在垃圾的焚烧处置效果。结果表明,该系统可满足高原高寒地区灾害现场200 kg/h垃圾应急保障处置工作,烟气排放符合GB 18484—2020《危险废物焚烧污染控制标准》要求,可有效为高原高寒地区垃圾处置提供技术及装备支撑。

关键词：移动焚烧系统高原高寒医疗垃圾动物尸体

Urinary Creatinine Concentrations and Its Explanatory Variables in General Chinese Population:Implications for Creatinine Limits and Creatinine Adjustment

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Biomedical and Environmental Sciences 2022年第10期35卷 899-910页

作者： ji sai sai LYU Yue Bin QU Ying Li HU Xiao jian LU Yi Fu CAI Jun Fang SONG Shi Xun ZHANG Xu LIU Ying Chun YANG Yan Wei ZHANG Wen Li LI Ya Wei ZHANG Ming Yuan CHEN Chen LI Cheng Cheng LI Zheng GU Heng LIU Ling CAI jia Yi QIU Tian FU Hui ji S.John ZHAO Feng ZHU Ying CAO Zhao jin SHI Xiao Ming China CDC Key Laboratory of Environment and Population Health National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijing 100021China School of Public Health Jilin UniversityChangchun 130021JilinChina Vanke School of Public Health Tsinghua UniversityBeijing 100084China

Objective The study aimed to analyze the applicability of the World Health Organization’s exclusionary guidelines for Urinary creatinine(Ucr)in the general Chinese population,and to identify Ucr related factors.Methods We conduct a cross-sectional study using baseline data from 21,167 participants in the China National Human Biomonitoring Program.Mixed linear models and restricted cubic splines(RCS)were used to analyze the associations between explanatory variables and Ucr concentration.Results The geometric mean and median concentrations of Ucr in the general Chinese population were 0.90 g/L and 1.01 g/L,respectively.And 9.36%samples were outside 0.3-3.0 g/L,including 7.83%below the lower limit and 1.53%above the upper limit.Middle age,male,obesity,smoking,higher frequency of red meat consumption and chronic kidney disease were associated significantly with higher concentrations of Ucr.Results of the RCS showed Ucr was positively and linearly associated with body mass index,inversely and linearly associated with systolic blood pressure,diastolic blood pressure,triglycerides level,and glomerular filtration rate,and were non-linearly associated with triiodothyronine.Conclusion The age-and gender-specific cut-off values of Ucr that determine the validity of urine samples in the general Chinese population were recommended.To avoid introducing bias into epidemiologic associations,the potential predictors of Ucr observed in the current study should be considered when using Ucr to adjust for variations in urine dilution.

关键词： Biomonitoring Urine Hydration correction Creatinine

Secure Provenance of Electronic Records Based on Blockchain

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Computers, Materials & Continua 2020年第11期65卷 1753-1769页

作者： Qirun Wang Fujian Zhu sai ji Yongjun Ren School of Engineering and Technology University of HertfordshireHertfordUK School of Computer and Software Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologyNanjing University of Information Science&TechnologyNanjing210044China

At present,the provenance of electronic records is stored centrally.The centralized way of information storage has huge risks.Whether the database itself is destroyed or the communication between the central database and the external interruption occurs,the provenance information of the stored electronic records will not play its role.At the same time,uncertainties such as fires and earthquakes will also pose a potential threat to centralized databases.Moreover,the existing security provenance model is not specifically designed for electronic records.In this paper,a security provenance model of electronic records is constructed based on PREMIS and METS.Firstly,this paper analyses the security requirements of the provenance information of electronic records.Then,based on the characteristics of blockchain decentralization,and combined with coding theory,a distributed secure provenance guarantees technology of electronic records is constructed,which ensures the authenticity,integrity,confidentiality and reliability of the provenance information.

关键词： Secure provenance electronic records blockchain

Impact Force Magnitude and Location Recognition of Composite Materials

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Computers, Materials & Continua 2020年第9期64卷 1647-1656页

作者： Yajie Sun Yanqing Yuan Qi Wang sai ji Lihua Wang Shao’en Wu jiangsu Engineering Centre of Network Monitoring Nanjing University of Information Science and TechnologyNanjing210044China School of Computer and Software Nanjing University of Information Science and TechnologyNanjing210044China School of Information and Control Nanjing University of Information Science and TechnologyNanjing210044China Department of Computer Science Ball State UniversityMuncieUSA

In order to identify the location and magnitude of the impact force accurately,determine the damage range of the structure and accelerate the health monitoring of key components of the composite,this paper studies the location and magnitude of the impact force of composite plates by an inverse method.Firstly,a PZT sensor mounted on the material plate is used to collect the response signal generated by the impact force,which is from several impact locations,and establish transfer functions between the impact location and the PZT sensor.Secondly,this paper applies several forces to any location on the material plate,and collects the corresponding response signals,and reconstructs the impact force of several locations in turn.Finally,according to the reconstruction result of each location,the correct impact location is identified.Then,an improved regularization method is used to optimize the reconstructed impact force and accurate the magnitude of the impact force.The comparison experiments prove that the recognition error of this method is smaller.

关键词： Impact force identification transfer function regularization