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Compressed Least Squares Algorithm of Continuous-Time Linear Stochastic Regression Model Using Sampling Data

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Journal of Systems Science & Complexity 2024年第4期37卷 1488-1506页

作者： XIE Siyu ZHANG Shujun wang ziming GAN Die School of Aeronautics and Astronautics University of Electronic Science and Technology of ChinaChengdu 611731China China Academy of Aerospace Science and Innovation Beijing 100176China Zhongguancun Laboratory Beijing 100094China

In this paper,the authors consider a sparse parameter estimation problem in continuoustime linear stochastic regression models using sampling *** on the compressed sensing(CS)method,the authors propose a compressed least squares(LS) algorithm to deal with the challenges of parameter *** each sampling time instant,the proposed compressed LS algorithm first compresses the original high-dimensional regressor using a sensing matrix and obtains a low-dimensional LS estimate for the compressed unknown ***,the original high-dimensional sparse unknown parameter is recovered by a reconstruction *** introducing a compressed excitation assumption and employing stochastic Lyapunov function and martingale estimate methods,the authors establish the performance analysis of the compressed LS algorithm under the condition on the sampling time interval without using independence or stationarity conditions on the system *** last,a simulation example is provided to verify the theoretical results by comparing the standard and the compressed LS algorithms for estimating a high-dimensional sparse unknown parameter.

关键词： Compressed excitation condition compressed sensing continuous-time model least squares linear stochastic regression parameter identification sampling data

A physical model study of surrounding rock failure near a fault under the influence of footwall coal mining

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International Journal of Coal Science & Technology 2021年第4期8卷 626-640页

作者： Shukun Zhang Lu Lu ziming wang Shuda wang School of City and Architecture Engineering Zaozhuang UniversityZaozhuang 277160ShandongChina School of Civil Engineering Liaoning Technical UniversityFuxin 123000LiaoningChina

A study of the deformation of the surrounding rock and coal pillars near a fault under the influence of mining is conducted on a physical model for the design of coal pillars to support and maintain the roofs of adjacent fault *** research is based on the 15101 mining face in the Baiyangling Coal Mine,Shanxi,China,and uses simulation tests similar to digital speckle test technology to analyse the displacement,strain and vertical stress fields of surrounding rocks near faults to determine the influence of the coal pillar *** results are as *** surrounding rock of the roadway roof fails to form a balance hinge for the massive rock *** vertical displacement,vertical strain and other deformation of the surrounding rock near the fault increase steeply as the coal pillar width *** steep increase in deformation corresponds to a coal pillar width of 10 *** the coal pillar width is 7.5 m,the pressure on the surrounding rock near the footwall of the fault suddenly increases,while the pressure on the hanging wall near the fault increases by only 0.35 *** stress of the rock mass of the hanging wall is not completely shielded by the fault,and part of the load disturbance is still transmitted to the hanging wall via *** width of the fault coal pillars at the 15101 working face is determined to be 7.5 m,and the monitoring data verify the rationality of the fault coal pillars.

关键词： Fault Mining roadway Surrounding rock Coal pillar Physical model

Symmetric-threshold ReLU for Fast and Nearly Lossless ANN-SNN Conversion

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Machine Intelligence Research 2023年第3期20卷 435-446页

作者： Jianing Han ziming wang Jiangrong Shen Huajin Tang College of Computer Science and Technology Zhejiang UniversityHangzhou310027China Zhejiang Lab Hangzhou311121China

The artificial neural network-spiking neural network(ANN-SNN)conversion,as an efficient algorithm for deep SNNs training,promotes the performance of shallow SNNs,and expands the application in various ***,the existing conversion methods still face the problem of large conversion error within low conversion time *** this paper,a heuristic symmetric-threshold rectified linear unit(stReLU)activation function for ANNs is proposed,based on the intrinsically different responses between the integrate-and-fire(IF)neurons in SNNs and the activation functions in *** negative threshold in stReLU can guarantee the conversion of negative activations,and the symmetric thresholds enable positive error to offset negative error between activation value and spike firing rate,thus reducing the conversion error from ANNs to *** lossless conversion from ANNs with stReLU to SNNs is demonstrated by theoretical *** contrasting stReLU with asymmetric-threshold LeakyReLU and threshold ReLU,the effectiveness of symmetric thresholds is further *** results show that ANNs with stReLU can decrease the conversion error and achieve nearly lossless conversion based on the MNIST,Fashion-MNIST,and CIFAR10 datasets,with 6×to 250 speedup compared with other ***,the comparison of energy consumption between ANNs and SNNs indicates that this novel conversion algorithm can also significantly reduce energy consumption.

关键词： Symmetric-threshold rectified linear unit(stReLU) deep spiking neural networks artificial neural network-spiking neural network(ANN-SNN)conversion lossless conversion double thresholds

Hydrothermal-deposition synthesis of MnO2/MnS nanorods as high-performance asymmetric supercapacitor positive electrode materials

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Progress in Natural Science:Materials International 2024年第5期34卷 1057-1065页

作者： ziming wang Hanbo wang Dongyu Pei Sheng Wan Yan wang Mingrui Yu Haiyan Lu College of Chemistry Jilin University Key Laboratory of Physics and Technology for Advanced Batteries Ministry of Education Jilin University Zhuhai Zhongli New Energy Sci-Tech Co. Ltd.

Nanostructuring has shown promise in enhancing the performance of MnO2for energy storage in supercapacitors,highlighting its technological significance. This study introduces an innovative synthesis method, employing hydrothermal and constant-pressure deposition techniques, to produce nanostructured MnO2/MnS rod electrodes on nickel foam. The roded heterostructure enhances specific surface area, conductivity, and symbiotic effect between MnO2and MnS. With optimized material and structural advantages, the electrode reaches a capacitance of 977.6 F g-1at 1 A g-1, demonstrating extended cycling lifespan. Using MnO2/MnS-5h rods as the positive electrode and activated carbon as the negative electrode, the supercapacitor achieves an energy density of 122.23Wh kg-1at 898.75 W kg-1. Notably, it maintains 91.55 % capacity retention after 5000 cycles at 10 A g-1,indicating outstanding cycling stability. This research presents a promising solution for efficient energy storage,emphasizing the potential application of the developed MnO2/MnS based supercapacitor in high-performance energy storage systems.

关键词： High energy density Nanostructured MnO2/MnS2 rod Outstanding cycling stability Supercapacitors

Ultrasonic Extraction Coupled with Capillary Electrophoresis for the Determination of Azo Dyes in Lipsticks Using Ionic Liquid as Dynamic Coating and Background Electrolyte

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Chinese Journal of Chemistry 2011年第1期29卷 147-152页

作者： Li, Dan wang, ziming wang, Lu Xu, Xu Zhang, Hanqi Department of Chemistry Jilin University Changehun Jilin 130012 China

A simple and rapid method based on ultrasonic extraction and capillary electrophoresis using l-butyl-3-methylimidazolium tetrafluoroborate as dynamic coating and background electrolyte was developed. The method was applied to the separation and determination of three azo dyes in two lipsticks. To increase extraction rate and yield, lipstick samples were coated on a glass slide before ultrasonic extraction. The dyes were extracted by ultrasonic extraction for 30 min, and then determined by capillary electrophoresis. Several experimental factors, such as ionic liquid concentration, pH value of background electrolyte and applied voltage, were examined and optimized. Under the optimal conditions, three azo dyes were completely separated within 12 min, and the detection limits for the three azo dyes ranged from 0.33 to 0.88 μg/mL. The recoveries were in the range of 96.8% to 108.8%.

关键词： capillary electrophoresis ionic liquids dyes lipstick

Refinement of structural characteristics and supercapacitor performance of MnO2 nanosheets via CTAB-assisted electrodeposition

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Progress in Natural Science:Materials International 2023年第6期33卷 881-890页

作者： ziming wang Hanbo wang Dongyu Pei Sheng Wan Zhitian Fan Mingrui Yu Haiyan Lu College of Chemistry Jilin University Key Laboratory of Physics and Technology for Advanced Batteries Ministry of Education Jilin University Zhuhai Zhongli New Energy Sci-Tech Co. Ltd.

MnO2stands out as a highly promising material for electrochemical capacitors due to its impressive theoretical capacitance,cost-effectiveness,eco-friendliness,and abundant natural ***,its inherent low conductivity and structural fragility result in restricted specific capacitance and a shortened cycle life,posing a notable obstacle to its *** the introduction of CTAB(cetyltrimethylammonium bromide),we successfully tailored the surface morphology of the electrode material,yielding a robust and highly conductive layered MnO2electrode *** MnO2/CTAB composite synthesized through a simple electrodeposition method exhibits outstanding performance,achieving a specific capacitance of 665 F g-1at 1 A *** after30,000 cycles,it maintains 92.13% *** performance improvement is primarily attributed to increased conductivity,and additional electrochemically active ***,the assembled MnO2/CTAB//AC capacitor(ACs) achieves a specific capacitance of 70.06 F g-1at 1 A g-1,operating at a voltage of 1.8 *** a power density of 563.36 W kg-1,it reaches an energy density of 35.21 Wh *** work provides an effective approach for high-performance electrode of supercapacitor.

关键词： Manganese dioxide CTAB Asymmetric capacitor Electrodeposition

The anodically polarized Mg surface products and accelerated hydrogen evolution

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Journal of Magnesium and Alloys 2023年第1期11卷 230-248页

作者： Jufeng Huang Guang-Ling Song Yixing Zhu Dajiang Zheng ziming wang Center for Marine Materials Corrosion and Protection College of MaterialsXiamen UniversityPeople’s Republic of China State Key Laboratory of Physical Chemistry of Solid Surfaces Xiamen UniversityXiamen 361005People’s Republic of China School of Engineering The University of QueenslandSt.LuciaQld 4072Australia

To clarify the anodic dissolution mechanism of Mg,the hydrogen evolution from pure Mg in acidic solutions under galvanostatic conditions were systematically *** increasing anodic current density,the cathodic hydrogen evolution rate decreased,and the anodic hydrogen evolution became faster while some surface area on the Mg was becoming dark under anodic *** on the surface analysis results and the generally accepted basic electrochemical equations,the evolution kinetics of hydrogen from Mg was deduced,and the most possible surface intermediate active species that could facilitate the anodic Mg dissolution and anodic hydrogen evolution were *** paper further develops the model of incomplete film Mg^(+) dissolution,explains many reported experimental phenomena,and clarifies misunderstandings of current mechanism.

关键词： Magnesium Corrosion Hydrogen evolution Negative difference effect

Microstructural Characteristics Analysis of PCE Copolymer from Methyl Allyl Polyethylene Glycol and Methacrylic Acid based on Determination of Monomer Reactivity Ratios

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Journal of Wuhan University of Technology(Materials Science) 2021年第2期36卷 223-229页

作者： wang ziming KANG Yaxin PENG Jingying College of Materials Science and Engineering Beijing University of TechnologyBeijing 100124China

The reactivity ratio of monomer and the microstructure of copolymer as polycarboxylate ether(PCE)superplasticizer were *** ethers(PCEs)were synthesized from methyl allyl polyethylene glycol(MAPEG,Mw=2400 g/mol)and methacrylic acid(MAA)via aqueous free radical copolymerization in low conversion(P<20%).Gel permeation chromatography(GPC)and high performance liquid chromatography(HPLC)were used to track the residual concentration of the reactants and the amount of copolymer formed during the *** reactivity ratios of monomers,MAPEG and MAA,were determined as r1(MAPEG)=0.0489 and r2(MAA)=1.6173,respectively,by employing the K-T and YBR *** to the obtained monomer reactivity results,the sequence distribution of the copolymer,the number average length of MAA in the polymerisate were found to decline with the decrease of the mole fraction of MAA in the polymerization *** a result,the distribution of chain segments becomes narrower and the copolymer structure becomes more ***,uniform polymers could be obtained by slowly adding MAA monomer during copolymerization process.

关键词： reactivity ratio polycarboxylate K-T method copolymer sequence distribution

Supplemental Feeding of Laying Hens with Wood Vinegar to Decrease the Ratio of n-6 to n-3 Fatty Acids in Eggs

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Chemical Research in Chinese Universities 2019年第6期35卷 983-989页

作者： ZHAO Nan XIN Hua LI Zhanchao wang ziming ZHANG Lening Department of Thoracic Surgery China-Japan Union Hospital of Jilin UniversityChangchun 130031P.R.China College of Chemistry Jilin UniversityChangchun 130012P.R.China

A balanced ratio of fatty acids n-6 to n-3 in chicken eggs is important for health and to help prevent and manage obesity and other ***,fish oil or flax seed has been utilized as feed additives to decrease the ratio of n-6 to n-3(n-6:n-3)fatty acids in *** hull of spina date seed(HSDS)is a common agricultural waste product in China,from which wood vinegar(HSDSWV)may be *** study evaluated HSDSWV as a sup-plement in hen feeds to improve the quality of eggs and decrease the ratio of fatty acids n-6:*** was obtained via carbonization,and *** concentrations(nil to 0.5%)of HSDSWV were prepared and fed to 6 hen groups,respectively,for 50 *** fatty acids of the hen’s egg yolks were analyzed by gas chromatography/electron ionization-mass spectrometry(GC/EI-MS)in the selected ion monitoring(SIM)*** 0.2%HSDSWV resulted in the best egg yolk quality,with a lower percentage of linoleic acid(C18:2n6)and higher percentages of cis-5,8,11,14,17-eicosapentaenoic acid(C20:5n3)and cis-4,7,10,13,16,19-docosahexaenoic acid(C22:6n3),and thus a lower n-6:n-3 ratio compared with the other HSDSWV *** addition,the eggs contained higher levels of yolk fat and egg yolk than the controls *** conclusion,to modify the fatty acid composition of hens’eggs and obtain a balanced ratio of n-6:n-3,0.2%HSDSWV may be considered suitable as a dietary supplement in hens’feed.

关键词： Gas chromatography/electron ionization-mass spectrometry(GC/EI-MS) Hull of spina date seed Wood vinegar n-3 fatty acid n-6 fatty acid