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Acta Mathematicae Applicatae Sinica 2023年第3期39卷 465-490页

作者： Gui-qin QIU Gao-wei cao Xiao-zhou YANG University of Chinese Academy of Sciences Beijing 100049China Wuhan Institute of Physics and Mathematics Innovation Academy for Precision Measurement Science and TechnologyCASWuhan 430071China

In this paper,we investigate the global solution and the structures of interaction between two dimensional non-selfsimilar shock wave and rarefaction wave of general two-dimensional scalar conservation law in which flux functions f(u)and g(u)do not need to be convex,and the initial value contains three constant states which are respectively separated by two general initial *** initial value contains three constant states,the cases of selfsimilar shock wave and rarefaction wave had been studied before,but no results of the cases of neither non-selfsimilar shock wave or non-selfsimilar rarefaction *** the assumption that Condition H which is generalization of one dimensional convex condition,and some weak conditions of initial discontinuity,according to all the kinds of combination of elementary waves respectively staring from two initial discontinuities,we get four cases of wave interactions as S+S,S+R,R+S and R+*** studying these interactions between non-selfsimilar elementary waves,we obtain and prove all structures of non-selfsimilar global solutions for all cases.

关键词： Riemann problem shock wave rarefaction wave wave interaction

Theoretical prediction of ground settlements due to shield tunneling in multi-layered soils considering process parameters

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Underground Space 2024年第3期16卷 29-43页

作者： Liqiang cao Xiangsheng Chen Dechun Lu Dingli Zhang Dong Su Institute of Geotechnical and Underground Engineering Beijing University of TechnologyBeijing 100124China Underground Polis Academy Shenzhen UniversityShenzhen 518060China Key Laboratory of Urban Underground Engineering of Ministry of Education Beijing Jiaotong UniversityBeijing 100044China Key Laboratory for Resilient Infrastructures of Coastal Cities(MOE) Shenzhen UniversityShenzhen 518060China

This paper conducts a theoretical analysis of ground settlements due to shield tunneling in multi-layered soils which are usually encountered in urban *** proposed theoretical solution which is based on the general form of the Mindlin’s solution and Loganathan-Poulos formula can comprehensively consider the in-process tunneling parameters including:unbalanced face pressure,shield-soil friction,unbalanced tail grouting pressure,unbalanced secondary grouting pressure,overloading during tunneling and the ground volume *** method is verified by comparing with the field data from the Qinghuayuan Tunnel Project in terms of the ground surface settlements along the longitudinal and transverse *** to the local settlement or heave caused by the certain tunneling parameters,the ground surface settlements calculated using current solution along the longitudinal direction presents an irregular S-shaped curve instead of the traditional S-shaped *** also find that the effect of the unbalanced secondary grouting pressure and the overloading during tunneling cannot be ignored.

关键词： Tunneling Shield Ground settlements Theoretical analysis Urban areas Multi-layered soils Qinghuayuan Tunnel

Preparation and performance improvement of a dual-component microcapsule self-healing system for silicone rubber insulating material

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High Voltage 2024年第2期9卷 453-465页

作者： Mingzhe Li Bin cao Fanghui Yin Hongwei Mei Liming Wang Engineering Laboratory of Power Equipment Reliability in Complicated Coastal Environments Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhenChina

A key factor limiting the development of silicone rubber insulating materials is their short service life in harsh operating *** establishment of a self-healing system is desired to improve the long-term operational performance of silicone rubber and effectively extend its service *** this study,poly(urea-formaldehyde)microcapsules containing polydimethylsiloxane healing agents are prepared and a dual-component microcapsule self-healing system for silicone rubber material is established and *** addition,the key factors affecting the self-healing performance(such as microcapsule size,rupture rate,and microcapsule doping amount)are *** is found that when SYLGARDTM 184 is used as the healing agent and matrix,with a 4:6(A:B)doping ratio of dual-component microcapsules and 20 phr doping amount,the self-healing efficiency is approximately 51%.Furthermore,increasing the microcapsule rupture rate and the interface strength between the healing agent and the matrix can effectively improve the self-healing *** relationships between key factors and self-healing performance are theoretically *** on the relationships,the microcapsule self-healing system can be appropriately *** results of this paper can provide a reference for the development of long-life silicone rubber insulating materials.

关键词： service rubber performance

Data-Driven Hybrid Neural Fuzzy Network and ARX Modeling Approach to Practical Industrial Process Identification

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IEEE/CAA Journal of Automatica Sinica 2022年第9期9卷 1702-1705页

作者： Feng Li Tian Zheng Naibao He Qingfeng cao College of Electrical and Information Engineering Jiangsu University of TechnologyChangzhou 213001China College of Electrical Energy and Power EngineeringYangzhou UniversityYangzhou 225127China

Dear editor,This letter presents a practical industrial process identification *** specifically,to improve the identification accuracy of practical process,a decoupled identification scheme is developed based on neural fuzzy network and autoregressive exogenous(ARX)model,which is based on multi-signal *** multiple signal sources include binary signals and random *** results of pH neutralization process show that developed identification scheme can provide accurate identification accuracy.

关键词： ARX editor Hybrid

Physical Properties and Electrochemical Performance of lini_xMn_(2-x)O_4 Cathode Materials Prepared using a Precipitation Method

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Journal of Materials Science & Technology 2006年第1期22卷 19-24页

作者： Guoguang WAN Jianming WANG Wenqu MAO Jianqing ZHANG Chunan cao Department of Chemistry Zhejiang University Hangzhou 310027 China State Key Laboratory for Corrosion and Protection Institute of Metal Research CAS Shenyang 110016 China

To improve the cycle performance of spinel LiMn204 as the cathode material of 4 V class Li secondary batteries, linixMn2-xO4 （x=0-0.3） samples were prepared using a simple precipitation method, and the effects of Ni doping on the physical properties and electrochemical performance of the samples were investigated using various methods. All linixMn2-xO4 （x=0-0.3） compounds show a single spinel phase, and the lattice parameter （a）, the unit cell volume （v） and particle size decrease with increasing Ni content. The results of the electrochemical experiments showed that the initial charge-discharge capacity of linixMn2-xO4 samples in the 3.0-4.4 V range decreases with increasing Ni content except for pure LiMn2O4; however, the capacity in the 4.4-4.9 V range increases with the increasing Ni content. For spinel samples Ni substitution can contribute to the improvement of their cycle performance due to the formation of the stronger Ni-O bond, homogeneous morphology, and sub-micron sized particles, and the sample with x=0.05 has larger peak currents, higher initial capacity and better cycling capability due to its lower electrochemical and diffusion polarization than those of other samples.

关键词： Ni-substituted LiMn2O4 Electrochemical performance Electrochemical impedance spectroscopy

Enzyme-loaded liposome with biocatalytic precipitation for potentiometric immunoassay of thyroid-stimulating hormone in thyroid carcinoma

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Chinese Chemical Letters 2020年第2期31卷 463-467页

作者： Yongjin cao Min Zheng Weihua Cai Zongcai Wang Department of Thyroid and Breast Surgery The First Affiliated Hospital of Fujian Medical UniversityFuzhou 350005China Department of Medical Oncology The First Affiliated Hospital of Fujian Medical UniversityFuzhou 350005China

A simple and feasible potentiometric immunosensing platform based on enzymatic biocatalytic precipitation technique was designed for the sensitive detection of thyroid-stimulating hormone(TSH;a typical kind of biomarkers for thyroid carcinoma),using horseradish peroxidase(HRP)-loaded liposome for the signal *** construct such an assay system,a sandwich-type immunoreaction was readily carried out on monoclonal anti-TSH capture antibody-coated electrode by using polyclonal antiTSH secondary antibody-conjugated HRP-loaded *** the formation of sandwichtype immunocomplex,the carried liposome was lysed through the added Triton X-100 to release the entrapped HRP molecules,which catalyzed the oxidation of 4-chloro-1-naphthol to produce an insoluble and uncharged organic precipitation on the electrode surface,thereby causing the change of the local electrical *** labeling protocols with and without the liposome were investigated for detection of target TSH,improved analytical features were achieved with HRP-entrapped *** optimal conditions,the potentiometric immunosensor had good responses for TSH detection within the linear range of 0.01-30 p IU/mL at a detection limit of 0.0067 p IU/*** reproducibility,high specificity and long-time stability were acquired during the assay ***,a wellmatched accuracy between the potentiometric immunosensor and commercial human TSH ELISA kit was gave for the analysis of human serum samples.

关键词： Potentiometer Modification electrode Potentiometric immunoassay Thyroid-stimulating hormone Enzyme-encapsulated liposome Enzyme biocatalytic precipitation

COMBAT:A New Bitmap Index Coding Algorithm for Big Data

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Tsinghua Science and Technology 2016年第2期21卷 136-145页

作者： Yinjun Wu Zhen Chen Yuhao Wen Wenxun Zheng Junwei cao Department of Automation and Tsinghua National Laboratory for Information Science and Technology(TNList) Tsinghua UniversityBeijing 100084China. iCenter of Tsinghua University Beijing 100084China Department of Computer Science Duke UniversityNC 27708USA. Research Institute of Information Technology and Tsinghua National Laboratory for Information Science and Technology(TNList) Tsinghua UniversityBeijing 100084China.

Bitmap indexing has been widely used in various applications due to its speed in bitwise operations. However, it can consume large amounts of memory. To solve this problem, various bitmap coding algorithms have been proposed. In this paper, we present COMbining Binary And Ternary encoding （COMBAT）, a new bitmap index coding algorithm. Typical algorithms derived from Word Aligned Hybrid （WAH） are COMPressed Adaptive indeX （COMPAX） and Compressed ＂n＂ Composable Integer Set （CONCISE）, which can combine either two or three continuous words after WAH encoding. COMBAT combines both mechanisms and results in more compact bitmap indexes. Moreover, querying time of COMBAT can be faster than that of COMPAX and CONCISE, since bitmap indexes are smaller and it would take less time to load them into memory. To prove the advantages of COMBAT, we extend a theoretical analysis model proposed by our group, which is composed of the analysis of various possible bitmap indexes. Some experimental results based on real data are also provided, which show COMBAT＇s storage and speed superiority. Our results demonstrate the advantages of COMBAT and codeword statistics are provided to solidify the proof.

关键词： bitmap index big data COMBAT CONCISE COMPAX index encoding performance evaluation

Rock burst mechanism analysis in an advanced segment of gob-side entry under different dip angles of the seam and prevention technology

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International Journal of Mining Science and Technology 2018年第6期28卷 891-899页

作者： Yang Zengqiang Liu Chang Tang Shichuan Dou linming cao Jinglong School of Resource and Safety Engineering China University of Mining and Technology State Key Laboratory of Coal Resources and Mine Safety China University of Mining and Technology Beijing Key Laboratory of Occupational Health and Safety Beijing Municipal Institute of Labor Protections

In order to investigate the frequent occurrences of rock burst in gob-side entry during the mining process of the mining zone No. 7, the mechanical model of main roof of fully-mechanized caving mining before breaking was established by the Winkler foundation beam theory, and the stress evolution law of surrounding rock with different dip angles of the seam during the mining process was analyzed by using FLAC3 D. The results show that: with the dip angle changing from 45° to 0°, the solid-coal side of gobside entry begins to form an L-shaped stress concentration zone at a dip angle of 30°, and the stress concentration degree goes to higher and higher levels. However, the stress concentration degree of the coalpillar side goes to lower and lower levels; the influence range and peak stress of the abutment at the lateral strata of adjacent gob increase with dip angle decreasing and reach a maximum value at a dip angle of 0°, but the tailgate is not affected; the abutment pressure superposition of two adjacent gobs leads to stress concentration further enhancing in both sides of gob-side entry. With the influence of strong mining disturbance, rock burst is easily induced by dynamic and static combined load in the advanced segment of gob-side entry. To achieve stability control similar to that in the roadway, the key control strategy is to reinforce surrounding rock and unload both sides. Accordingly, the large-diameter drilling and high-pressure water injection combined unloading and reinforced support cooperative control technology was proposed and applied in field test. The results of Electromagnetic Emission(EME) and field observation showed that unloading and surrounding rock control effect was obvious.

关键词： Rock burst Change of dip angle Gob-side entry Dynamic and static combined load Cooperative control Electromagnetic emission

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基于虚拟属性学习的文本-图像行人检索方法

软件学报 2023年第5期34卷 2035-2050页

作者：王成济苏家威罗志明曹冬林林耀进李绍滋厦门大学信息学院福建厦门361005 闽南师范大学计算机学院福建漳州363000 数据科学与智能应用重点实验室(闽南师范大学) 福建漳州363000

文本-图像行人检索旨在从行人数据库中查找符合特定文本描述的行人图像.近年来受到学术界和工业界的广泛关注.该任务同时面临两个挑战:细粒度检索以及图像与文本之间的异构鸿沟.部分方法提出使用有监督属性学习提取属性相关特征,在细粒... 详细信息

文本-图像行人检索旨在从行人数据库中查找符合特定文本描述的行人图像.近年来受到学术界和工业界的广泛关注.该任务同时面临两个挑战:细粒度检索以及图像与文本之间的异构鸿沟.部分方法提出使用有监督属性学习提取属性相关特征,在细粒度上关联图像和文本.然而属性标签难以获取,导致这类方法在实践中表现不佳.如何在没有属性标注的情况下提取属性相关特征,建立细粒度的跨模态语义关联成为亟待解决的关键问题.为解决这个问题,融合预训练技术提出基于虚拟属性学习的文本-图像行人检索方法,通过无监督属性学习建立细粒度的跨模态语义关联.第一,基于行人属性的不变性和跨模态语义一致性提出语义引导的属性解耦方法,所提方法利用行人的身份标签作为监督信号引导模型解耦属性相关特征.第二,基于属性之间的关联构建语义图提出基于语义推理的特征学习模块,所提模块通过图模型在属性之间交换信息增强特征的跨模态识别能力.在公开的文本-图像行人检索数据集CUHK-PEDES和跨模态检索数据集Flickr30k上与现有方法进行实验对比,实验结果表明了所提方法的有效性.

关键词：行人检索跨模态属性学习预训练

Experimental evaluation of a 10-kW parabolic trough solar reactor prototype driving Ni-based chemical looping redox cycle with methane for solar fuel production

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Science China Technological Sciences 2024年第12期67卷 3741-3754页

作者： JIANG QiongQiong cao YaLi SUN Fan XING XueLi HONG Hui Key Laboratory of Power Station Energy Transfer Conversion and System of MOE School of Energy Power and Mechanical EngineeringNorth China Electric Power University State Power Investment Corporation Hydrogen Energy School of Aeronautics and Astronautics University of Chinese Academy of Sciences Institute of Engineering Thermophysics Chinese Academy of Sciences China Huaneng Group Clean Energy Association Research Institute

Solar fuels can be cost-effectively produced using solar-driven thermochemical processes. Hybridizing thermochemical processes can not only effectively utilize solar energy but also achieve clean conversion of fossil fuels. With this method, the solar energy level can be upgraded, and the irradiation fluctuation can be solved. It is worth noting that solar reactors play an important role in this technology. In this study, we demonstrated a 10-kW parabolic trough solar-driven reactor prototype for methane reforming and solar fuel production. The primary setup of the experimental platform consisted of a trough concentrating solar collector, chemical looping reforming reactors with indirect heat transfer, and associated auxiliary equipment. Experiments on the chemical looping redox cycle were conducted using nickel-based NiO/NiAl2O4as the OC under different direct normal irradiation（DNI） from 740 to 920 W/m2. Under irradiation at approximately 920 W/m2, the methane conversion initially increased to 92% before declining to 75% from 0 to 900 s and then to 2500 s. Under these conditions, the syngas concentration increased from 30% to 57% and the solar-to-fuel efficiency reached 59%. The oxygen transfer rate during the chemical looping redox cycle was also experimentally investigated. Cyclic redox cycle experiments were conducted for 540 min of long-term operation to assess the duration and adaptability performance. The fractional oxidation can consistently return to almost 1.0 after each redox cycle, indicating strong reactivity and regenerability when exposed to different levels of DNI. The reactivity of the chemical looping redox cycle during typical autumn and winter days was also investigated and discussed. This study aimed to prove that this 10-kW parabolic trough reactor prototype can harness 500°C solar heat to drive efficient methane reforming,offering a promising avenue for solar fuel production.

关键词： solar fuel solar reactor chemical looping thermochemical redox cycle methane reforming