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Fractional Order Proportional Integral Derivative Controller Design and Simulation for Bioengineering Systems

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Journal of Harbin Institute of Technology(New Series) 2013年第5期20卷 46-50页

作者： wei-cheng fu Chun-Yang Wang Yao-Wu Shi Ying-Bin Sun Dept. of Electronic and Information Engineering Changchun University of Science and Technology Dept. of Communication Engineering Jilin University

This paper deals with the study of fractional order system tuning method based on Factional Order Proportional Integral Derivative( FOPID) controller in allusion to the nonlinear characteristics and fractional order mathematical model of bioengineering systems. The main contents include the design of FOPID controller and the simulation for bioengineering systems. The simulation results show that the tuning method of fractional order system based on the FOPID controller outperforms the fractional order system based on Fractional Order Proportional Integral( FOPI) controller. As it can enhance control character and improve the robustness of the system.

关键词： robustness bioengineering systems fractional order proportional integral derivative controller

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应用于高能激光器的XY离焦像差校正方法

中国光学（中英文） 2024年第2期17卷 366-373页

作者：冯亚飞韦承甫任晓明郭建增王杰中国船舶集团有限公司第七一八研究所河北邯郸056027

针对高能激光器出光过程中出现的大量离焦和0°像散低阶像差现象,提出了基于哈特曼波前传感器和二维整形光路的XY离焦像差校正方法。首先,通过对Zernike多项式的离焦项和0°像散项进行线性组合得到XY离焦像差的表达式,该XY离焦像差系数... 详细信息

针对高能激光器出光过程中出现的大量离焦和0°像散低阶像差现象,提出了基于哈特曼波前传感器和二维整形光路的XY离焦像差校正方法。首先,通过对Zernike多项式的离焦项和0°像散项进行线性组合得到XY离焦像差的表达式,该XY离焦像差系数的大小可直接表征X离焦和Y离焦的波前PV值。同时,通过微调高能激光器中二维整形光路中的镜子间距,可实现激光器输出光束XY离焦波面的补偿。因此,首先利用哈特曼波前传感器提取出光束的XY离焦像差系数大小,而后再根据XY离焦像差系数的大小实时闭环微调二维整形光路中的镜子间距,从而实现XY离焦像差的校正,改善输出光束的光束质量。实验结果表明,该方法可有效地将高能激光器输出光束XY离焦量的PV值由5.2μm和1.1μm校正到0.5μm以下,相应的光束质量β因子由3.1降到1.8,光束质量得到明显改善。

关键词：高能激光光束质量像差校正光束整形矩阵光学

The Inexistence of Symmetrical,Orthonormal and Compactly Supported Three-Band Wavelet System with the Length(6,m,n)

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Journal of Mathematical Research and Exposition 2010年第6期30卷 1071-1077页

作者： Zheng wei SHEN Yu LIU wei XU fu cheng LIAO Department of Mathematics and Mechanics School of Applied ScienceUniversity of Science and Technology BeijingBeijing 100083P.R.China

This paper proves the inexistence of symmetric,orthonormal and commpactly supported three-band wavelet system with the length（6,m,n） in terms of the method of polyphase matrix representation.

关键词： wavelets polyphase matrix filters.

Mesoporous polymers:soft-template self-assembly synthesis and applications

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Science China Chemistry 2024年第5期67卷 1442-1464页

作者： Facai wei Tingting Zhang Jianwei fu chengbin Jing Jiangong cheng Shaohua Liu State Key Laboratory of Precision Spectroscopy Engineering Research Center of Nanophotonics&Advanced Instrument(Ministry of Education)School of Physics and Electronic ScienceEast China Normal UniversityShanghai 200241China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450052China State Key Lab of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China

Mesoporous polymers combine the advantages of polymer materials(abundant polar functional groups,lightweight,flexibility,and processability)and mesoporous structures(high specific surface area,adjustable pore structure,and large pore volume);hence,they have great application potential in sensing,adsorption,catalysis,energy storage,biomedicine,***,developing advanced synthetic strategies for mesoporous polymers and investigating their intrinsic applications have become hot research ***-template-based self-assembly is regarded as a promising approach for synthesizing mesoporous *** work reviews recent progress in the synthetic strategy for producing various mesoporous polymers using soft-template selfassembly,focusing on the synthesis of conductive polymers,phenol-based polymers,and resin-based polymers and their potential ***,perspectives on future applications of mesoporous polymers,along with a few challenges that need to be resolved,are also discussed in this review.

关键词： mesoporous polymer porous material self-assembly soft templates interface synthesis

Preparation of yttrium oxide coating with enhanced thermal shock resistance on refractories used for titanium alloy melting and casting

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Journal of Iron and Steel Research International 2024年第6期31卷 1411-1422页

作者： Ao Chen Yan Ma Zhou-fu Wang Hao Liu Xi-tang Wang Sen-na Chen Chen-xin Zhang Zi-yi Tang wei-dong fu wei cheng The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Xiangyang Juli High Technology Material Co. Ltd.Xiangyang 441705HubeiChina Xiangyang Public Inspection and Testing Center Xiangyang 441000HubeiChina

In order to enhance the service life of refractories for melting and casting of titanium alloy,preparation of yttrium oxide coatings on the refractories surface is an effective *** improvement of thermal shock stability of the coating is beneficial to its spalling resistance during the high-temperature service,and the available slurry with good performance is the *** effects of the varieties and contents of dispersant(sodium tripolyphosphate,sodium hexametaphosphate,sodium pyrophosphate,citric acid and polycarboxylate ammonium salt)and binder(aluminum dihydrogen phosphate,zirconium acetate and yttria sol)on the stability,rheological and thixotropic properties of yttrium oxide waterbased slurry were investigated,and the effects of slurry composition design on the thermal shock resistance of the coating were *** results showed that the introduction of polycarboxylate ammonium salt as dispersant significantly improved the stability of the slurry,and the varieties of the binders had significant effects on the dispersibility of the *** aluminum dihydrogen phosphate and polycarboxylate ammonium salt were used as binder and dispersant,respectively,the slurry had better stability,suitable rheological and thixotropic *** using aluminum dihydrogen phosphate as binder,the coating had good thermal shock resistance and no obvious cracks were observed for the coating after thermal shock,which was attributed to the yttrium aluminate binding phase generated in the *** effective method was provided for preparing yttrium oxide coatings with enhanced thermal shock resistance applied in the process of titanium alloy melting and casting.

关键词： Yttrium oxide-Slurry Stability Rheological property Thixotropic property-Coating Thermal shock resistance

Development of component stiffness equations for thread-fixed one-side bolt connections to an enclosed rectangular hollow section column under tension

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Frontiers of Structural and Civil Engineering 2024年第4期18卷 568-586页

作者： fu-wei WU Yuan-Qi LI Department of Structural Engineering Tongji UniversityShanghai 200092China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China

The derivation and validation of analytical equations for predicting the tensile initial stiffness of threadfixed one-side bolts(TOBs),connected to enclosed rectangular hollow section(RHS)columns,is presented in this *** unknown stiffness components are considered:the TOBs connection and the enclosed RHS ***,the trapezoidal thread of TOB,as an equivalent cantilevered beam subjected to uniformly distributed loads,is analyzed to determine the associated *** on the findings,the thread-shank serial-parallel stiffness model of TOB connection is *** analysis of the tensile stiffness of the enclosed RHS face due to two bolt forces,the four sidewalls are treated as rotation constraints,thus reducing the problem to a two-dimensional plate *** to the load superposition method,the deflection of the face plate is resolved into three components under various boundary and load *** to the plate deflection theory of Timoshenko,the analytical solutions for the three deflections are derived in terms of the variables of bolt spacing,RHS thickness,height to width ratio,***,the validity of the above stiffness equations is verified by a series of finite element(FE)models of T-stub *** proposed component stiffness equations are an effective supplement to the component-based method.

关键词： initial stiffness component based method thread-fixed one-side bolt rectangular hollow sections analytical equation

Streamflow abrupt change and the driving factors in glacierized basins of Tarim Basin,Northwest China

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Advances in Climate Change Research 2024年第1期15卷 75-89页

作者： cheng-De YANG Min XU Shi-Chang KANG Cong-Sheng fu wei ZHANG Di-Di HU State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Watershed Geographic Sciences Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210000China

A climate transition towards warm-wet conditions in Northwest China has drawn much *** continuous climate change and universal glacier degradation,increasing water-related hazards and vulnerability have become one of the important problems facing the Tarim ***,the impacts of the climate transition on streamflow abrupt change and extreme hydrological events were less discussed,especially in glacial *** the present study,the discharge datasets in four glacial basins of Tarim Basin from 1979 to 2018 were constructed using the GRU-GSWAT+model *** differences in streamflow characteristics,the shift of hydrological extreme pattern,and potential changes of the controlling factors before and after the abrupt changes were *** results indicated that the abrupt change point(ACP)in streamflow occurred in 2000 in the Qarqan River Basin,2002 in the weigan River Basin,and 1994 in the Aksu River Basin and the Yarkant River Basin.A general decrease in streamflow before the ACP has shifted to a notable upward trend in the Qarqan River Basin and the Aksu River Basin,while minor upward fluctuations were observed in other ***,the hydrological characteristics in extreme events vary dramatically before and after the ACPs,characterized by a pronouncing shift from drought-dominant pattern to wet events dominated *** driven climate factors have been altered after the ACPs with notable spatial heterogeneity,in which temperature remained as the dominant role in meltwater-dominated basins while the influence of precipitation has increased after the ACPs,whereas the sensitivity of temperature on streamflow change has been enhanced in basins dominated by precipitation such as the Qarqan River *** to the evident warming-wetting trend and glacier compensation effect,both the inter-annual and intra-annual streamflow fluctuations can be efficiently smoothed in basins with a high glacier area ratio(GAR).These findings provide a

关键词： Abrupt change Streamflow Hybrid model Tarim Basin Glacier

Nitric oxide assists nitrogen reduction reaction on 2D MBene: A theoretical study

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Chinese Chemical Letters 2024年第5期35卷 428-433页

作者： Chaozheng He Jia Wang Ling fu wei wei Henan Engineering Center of New Energy Battery Materials College of Chemistry and Chemical EngineeringShangqiu Normal UniversityShangqiu 476000China School of Chemistry and Chemical Engineering Shandong Provincial Key Laboratory/Collaborative Innovation Center of Chemical Energy Storage&Novel Cell TechnologyLiaocheng UniversityLiaocheng 252059China Institute of Environment and Energy Catalysis Shaanxi Key Laboratory of Optoelectronic Functional Materials and DevicesSchool of Materials Science and Chemical EngineeringXi’an Technological UniversityXi’an 710021China College of Resources and Environmental Engineering Tianshui Normal UniversityTianshui 741001China

Electrocatalytic synthesis of ammonia as an environment-friendly and sustainable development method has received widespread attention in recent ***-dimensional(2D)materials are a promising catalyst for ammonia synthesis due to their large surface *** this work,we have constructed a series of 2D metal borides(MBenes)with transition metal(TM)defects(TMd-MBenes)and comprehensively calculated the reactivity of electrocatalytic synthesis of ammonia-based on density functional *** results have demonstrated that the TMd-MBenes can effectively activate nitrogen oxide(NO)and nitrogen(N2)molecules *** interesting,the co-chemisorption of O atoms,dissociated from NO,can facilitate the spilled of the inert N2 molecules into single N atoms,which can further hydrogenate into ammonia easily with an ultralow limiting potential of 0.59 V on *** research has not only provided clues for catalyst design for experimental study but also paved the way for the industrial application of electrocatalytic ammonia synthesis.

关键词： 2D mbenes Nitrogen electro-reduction DFT N_(2)activation Ammonia synthesis

Nutrient transport following water transfer through the world's largest water diversion channel

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Journal of Environmental Sciences 2024年第1期135卷 703-714页

作者： Yuanhui cheng Hong Zhang wei Yin State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085 China Changjiang Water Resources Protection Institute Wuhan 430051China University of Chinese Academy of Sciences Beijing 100049China

Nutrient levels in the artificial channel constructed for the Middle Route Project are significant indicators of water quality safety and aquatic ecological integrity for this large,interbasin ***,the distribution and transport of nutrients along the channel were poorly *** on a time-series dataset as well as mass balance and material flow analysis methods,the water and nutrient transport fluxes in the Middle Route of the South-to-North Water Diversion Project were identified in this *** results indicate that the nutrient concentrations varied considerably with time,but there was no significant difference among the 30 stations of the main *** temperature difference was the major factor in the large fluctuations of water quality indicators over *** nutrient loadings varied with the water volume outputs from the main channel to the waterreceiving *** deposition was an important source of nutrients in the main channel,accounting for 9.13%,20.6%,and 0.635%of the nitrogen,phosphorus,and sulfur input from the Danjiangkou Reservoir,*** 2021,a net accumulation of 988 tons of N,29 tons of P,and 2,540 tons of S,respectively,were present in the main *** increase of these external and internal nutrient loadings would cause water quality fluctuation and deterioration in some local sections of the main *** study quantified the spatial and temporal patterns of nutrient transport in the Middle Route and revealed the ecological effects on the aquatic environment,assisting authorities on the project to develop effective water conservation strategies.

关键词： Nutrient transport Spatiotemporal patterns The Middle Route The South-to-North Diversion Project Hydro-ecological effects Water-receiving cities