检索结果-南通市图书馆

Adaptive Observer-Based Finite-Time Fault Tolerant Control for Non-Strict Feedback Systems

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2024年第4期37卷 1526-1544页

作者： sheng Ning liu yang CHI Ronghu ai Zidong College of Automation and Electronic Engineering Qingdao University of Science and TechnologyQingdao 266042China

This paper considers the adaptive finite-time control and observer design method for a class of non-strict feedback systems with unmeasurable states,unknown nonlinear dynamics and actuator *** this paper,an observer is proposed to estimate the unmeasurable states in finite-time based on adaptive technique and neural networks,while the actuator faults are not *** filter is used to solve the computational explosion and singularity problems caused by the traditional backstepping and non-strict feedback structure,*** the fault efficiency indicators in real systems are not available,two-layer neural networks are adopted,where the first network is to estimate the unknown nonlinearities of systems and the second one is to estimate fault efficiency indicators and unknown nonlinear *** proposed scheme guarantees that states are bounded through stability ***,two experiments including a numerical example and a spring-mass-damper system are given to verify the effectiveness of the proposed method.

关键词： Command filter fault tolerant control finite-time control non-strict systems two-layer neural networks

Potential application of radiant floor cooling systems for residential buildings in different climate zones

在线全文

学校读者我要写书评

暂无评论

Building Simulation 2024年第4期17卷 543-560页

作者： Mengying Cui yang Song yudong Mao Kaimin yang Jiying liu Zhe Tian School of Thermal Engineering Shandong Jianzhu UniversityJinan250101China School of Environmental Science and Engineering Tianjin UniversityTianjin300072China Key Lab of Building Environment and Energy of Tianjin Tianjin UniversityTianjin300072China

A radiant floor cooling system(RFCS)is a high-comfort and low energy consumption system suitable for residential *** floor systems usually work with fresh air,and their operating performance is affected by climatic *** and outdoor environmental disturbances and the system’s control strategy affect the indoor thermal comfort and energy efficiency of the ***,a multi-story residential building model was established in this *** system simulation program was used to study the operation dynamics of three control strategies of the RFCS based on the calibrated ***,the performance of the control strategies in five climate zones in China were compared using multi-criteria decision-making in *** results show that control strategy has a negligible effect on condensation risk,but the thermal comfort and economic performance differ for different control *** adaptability of different control strategies varies in different climate zones based on the consideration of multiple *** performance of the direct-ground cooling source system is better in Hot summer and warm winter *** variable air volume control strategy scores higher in Serve cold and Temperate zones,and the hours exceeding thermal comfort account for less than 3%of the total simulation ***,it is suggested to choose the RFCS control strategy for residential buildings according to the climate zone characteristics,to increase the energy *** results provide a reliable reference for implementing RFCSs in residential buildings.

关键词： control strategy radiant floor cooling system residential building energy efficiency climate zones

Preparation of Polyurea Elastomer with Flame Retardant, Insulation and Thermal Conductivity Properties

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 781-789页

作者：方今 DOng yang LU Shangkai liu Junbang ai Lianghui 刘平 State Key Laboratory of Luminescent Materials and Devices Research Institute of Materials ScienceSouth China University of TechnologyGuangzhou 510640China

By using 6,6-((sulfonylbis(4,1-phenylene)bis(azanediyl))bis(thiophen-2-ylm-ethylene))bis6H-di-benzo[c,e][1,2]oxaphosphinine 6-oxide(DOPO-N)as phosphorus-nitrogen flame retardant,the polyurea(PUA)with flame retardant properties(PUA/DOPO-N)was *** addition,organically modified montmorillonite(OMMT)and magnesium hydroxide(MH)were used as co-effectors respectively,and the flame retardant PUA(PUA/DOPO-N/OMMT and PUA/DOPO-N/MH)were also *** properties,flame retardant properties,flame retardant mechanism and mechanical properties of PUA/DOPO-N,PUA/DOPO-N/OMMT and PUA/DOPO-N/MH were investigated by thermogravimetric(Tg)analysis,limiting oxygen index(LOI),UL 94,cone calorimeter test,scanning electron microscopy(SEM),and tensile *** results show that the LOI value of PUA/20%DOPO-N,PUA/18%DOPO-N/2%OMMT and PUA/15%DOPO-N/5%MH are 27.1%,27.7%,and 28.3%,respectively,and UL 94 V-0 rating is *** with PUA,the peak heat release rate(pk-HRR),total heat release(THR)and average effective heat combustion(av-EHC)of PUA/20%DOPO-N,PUA/18%DOPO-N/2%OMMT and PUA/15%DOPO-N/5%MH decrease *** results indicate that the residual chars of PUA/20%DOPO-N,PUA/18%DOPO-N/2%OMMT and PUA/15%DOPO-N/5%MH are completer and more *** complex of DOPO-N/OMMT and DOPO-N/MH have synergistic flame *** mechanical properties of PUA can be improved by the addition of DOPO-N,DOPO-N/OMMT and DOPO-N/MH,*** insulation performance test shows that the volume resistivity of PUA/20%DOPO-N is 6.25×10^(16)Ω.***,by using modified boron nitride(MBN)as heat dissipating material,the complex of PUA/MBN was prepared,and the thermal conductivity of PUA/MBN was *** thermal conductivity of PUA/8%MBN complex coating at room temperature is 0.166 W/(M·K),which is a 163%improvement over pure PUA.

关键词： polyurea organic flame retardant inorganic flame retardant synergistic flame retardancy insulation thermal conductivity

Identification of Motor Nuclei in the Medulla Oblongata of Carp for Biological Control

在线全文

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2024年第2期21卷 842-851页

作者： yang Zhao Yong Peng yudong Wen Lingjun Han Yanhong Yan Xueying Dong Hui Zhang Zheng Zhao Xiaoyue liu School of Electrical Engineering Yanshan UniversityQinhuangdao066004China School of Mechanical Engineering Yanshan UniversityQinhuangdao066004China Key Laboratory of National Defense of Mechanical Structure and Material Science Under Extreme Conditions Yanshan UniversityQinhuangdao066004China Institute of Marine Science and Engineering Yanshan UniversityQinhuangdao066004China Shijiazhuang University Shijiazhuang050035China

Brain-controlled technology is the key technology in biological control,and the corresponding relationship between animal brain nuclei and motor behavior is the *** purpose of this study was to explore the motor nuclei of the medulla oblongata in *** carps were subjected to electrical stimulation and chemical stimulation experiments,respectively,in the water-free state,and the effective chemical stimulation sites were injected with the pontamine sky blue *** brain tissue sections were obtained by paraffin tissue section technology and the neutral red staining *** comparing the positions of the brain nuclei shown in earlier studies,the motor nerve nuclei in the medulla oblongata were *** brain electrode was implanted into the motor nucleus of the medulla oblongata,and the underwater control experiment and behavioral tests were carried out with different electrical stimulation *** results showed that the abducens nucleus(NVI)was the motor nucleus that controls the ipsilateral steering,and the facial nucleus(NVII)was the motor nucleus that controls the forward *** adjusting the stimulation voltage and the stimulation pulse number,the carp can be stably controlled to achieve a left–right steering motion of 30°–180°and a forward motion of more than 80 cm/*** study indicated that the quantitative control of the steering and forward behavior of the carp can be achieved by electrical stimulation of the NVI and NVII,which provided a certain experimental basis for the accurate control of the carp robot.

关键词： Biological control Carp Medulla oblongata motor nucleus Electrical stimulation technique Chemical stimulation technique

Asymptotic behavior of an SIQR epidemic model driven by Lévy jumps on scale-free networks

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Biomathematics 2024年第2期17卷 51-86页

作者： Yuncheng Xu sanyang liu Xiaojun Sun Hua Hu Yu Wang School of Mathematics and Statistics Xidian University Xi'an 710071P.R.China School of Mathematics and Statistics Ning Xia University Ningria 750021P.R.China School of Mathematics and Information Science Bao Ji University of Arts and Sciences Baoji 721013 P.R.China College of Mathematics Science and Center for Applied Mathematical Science Inner Mongolia Normal University Hohhot 010022 P.R.China

To investigate the effect of information transmission,Levy jumps and contact heterogeneity of individuals on the asymptotic behavior of epidemic,a stochastic SIQR epidemic model with non-monotone incidence rate and Levy jumps on scale-free networks is *** first,the global dynamics of the deterministic model is studied by constructing appropriate Lyapunov *** the stochastic model is made in accordance with the ecological significance,the existence and uniqueness of the global positive solution of the stochastic SIQR model is ***,by constructing suitable stochastic Lyapunov functions and applying Ito formula with jump,the asymptotic behavior of solutions of stochastic model around equilibrium of the corresponding deterministic model is *** last,the correctness of the analytical results is verified by numerical simulations.

关键词： Lévy jumps asymptotic behavior non-monotone incidence rate scale-free networks SIQR.

A lightweight and high compressive resistance thermal insulation material with dual-network structure

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第5期17卷 4279-4287页

作者： Mengmeng yang Zhaofeng Chen yang Ding Wu Qiong Tianlong liu Manna Li Lixia yang sheng Cui School of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites Nanjing Tech UniversityNanjing 211816China

Ceramic fibrous aerogels are highly desirable for thermal management materials due to their high porosity,excellent elasticity,thermal conductivity,and good thermal ***,the fabrication of nanofibrous aerogel with super-elasticity and good shape retention at the same time has remained *** meet the requirements,a novel anisotropy nanofibrous-granular aerogel with a quasi-layered multi-arch-like and hierarchical-cellular structure is designed and prepared by vacuum-filtration-assisted freeze-drying and *** quasi-layered multi-arch and flexible nanofibers endowed the aerogels with excellent mechanical robustness(ultimate stress up to 60 kPa with strain 60%)and super-elasticity with recoverable compression strain up to 60%.The introduced SiO_(2) aerogel nanoparticles and nanofibers are assembled into an arch-like structure and become the connection point of adjacent nanofibers,which endows low thermal conductivity(0.024 mW/(m·K))of composite *** novel strategy provides a fresh perspective for the preparation of nanofibrous aerogel with robust mechanical in thermal insulation and other fields.

关键词： nanofibrous aerogel dual-network structure thermal insulation nanofibrous-granular composite aerogels strong mechanical

generalized Embedding Machines for Recommender Systems

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Machine Intelligence Research 2024年第3期21卷 571-584页

作者： Enneng yang Xin Xin Li Shen yudong Luo guibing guo Software College Northeastern UniversityShenyang110000China School of Computer Science and Technology Shandong UniversityQingdao266000China JD Explore Academy JD Explore AcademyBeijing100000China

Factorization machine (FM) is an effective model for feature-based recommendation that utilizes inner products to capture second-order feature interactions. However, one of the major drawbacks of FM is that it cannot capture complex high-order interaction signals. A common solution is to change the interaction function, such as stacking deep neural networks on the top level of FM. In this work, we propose an alternative approach to model high-order interaction signals at the embedding level, namely generalized embedding machine (gEM). The embedding used in gEM encodes not only the information from the feature itself but also the information from other correlated features. Under such a situation, the embedding becomes high-order. Then we can incorporate gEM with FM and even its advanced variants to perform feature interactions. More specifically, in this paper, we utilize graph convolution networks (gCN) to generate high-order embeddings. We integrate gEM with several FM-based models and conduct extensive experiments on two real-world datasets. The results demonstrate significant improvement of gEM over the corresponding baselines.

关键词： Feature interactions high-order interaction factorization machine(FM) recommender system graph neural network(gNN)

Response characteristics of PWR primary circuit under SBLOCAs considering steam bypass discharging

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2024年第6期35卷 189-201页

作者： Shuai yang Xiang-Bin Li Yu-sheng liu Jia-Ning Xu De-Chen Zhang School of Nuclear Science and Engineering North China Electric Power UniversityBeijing 102206China Beijing Key Laboratory of Passive Safety Technology for Nuclear Energy Beijing 102206China Nuclear and Radiation Safety Center MEPBeijing 100084China

Small-break superposed station blackout(SBO)accidents are the basic design accidents of nuclear power *** the condition of a small break in the cold leg,SBO further increases the severity of the accident,and the steam bypass discharg-ing system(gCT)in the second circuit can play an important role in guaranteeing core *** explore the influence of the gCT on the thermal-hydraulic characteristics of the primary circuit,RELAP5 software was used to establish a numerical model based on a typical pressurized water reactor nuclear power *** different small breaks in the cold-leg super-posed SBO were selected,and the impact of the gCT operation on the transient response characteristics of the primary and secondary circuit systems was *** results show that the gCT plays an indispensable role in core heat removal during an accident;otherwise,core safety cannot be *** gCT was used in conjunction with the primary safety injection system during the placement *** the break diameter was greater than a certain critical value,the core cooling rate could not be guaranteed to be less than 100 K/h;however,the core remained in a safe state.

关键词： Steam bypass discharging Pressurized water reactor SBLOCA Numerical simulation

Narrowband blue emitter based on fused nitrogen/carbonyl combination with external quantum efficiency approaching 30%

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2024年第1期67卷 351-359页

作者： Long Chen Jia-Heng Cai You-Jun Yu yang-Kun Qu sheng-Yi yang sheng-Nan Zou Rui-Hong liu Dong-Ying Zhou Liang-sheng Liao Zuo-Quan Jiang Institute of Functional Nano&Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials&DevicesSoochow UniversitySuzhou 215123China Macao Institute of Materials Science and Engineering Macao University of Science and TechnologyMacao 999078China

Multi-resonance thermally activated delayed fluorescence(MR-TADF)emitters can enable narrowband emission with high color purity and electroluminescence ***/carbonyl(N/C=O)system is receiving increasing attention while the nitrogen/boron(N/B)system has been widely *** decoration is an effective approach for N/B type MR-TADF system but always leads to broadening and red-shifting of the emission band in N/C=O MR-TADF *** attribute these unfavorable phenomena to the formation of intramolecular charge transfer between the MR-core and peripheral *** address this issue,we have developed a new strategy by decorating DMQAO(a fused N/C=O MR-core)with a triazine acceptor and a neutral terphenyl group to construct MTDMQAO and MBDMQAO,*** introduction of the triazine acceptor not only realizes efficient narrowband emission in MTDMQAO,but also accelerates the reverse intersystem crossing process through enhanced spin-orbital *** a result,MTDMQAO exhibits a significantly higher external quantum efficiency of 29.4%compared to the referent emitters,validating the rationality of our derivation *** study highlights the potential of the N/C=O system for MR-TADF emitters and provides important insights for understanding the difference between N/B and N/C=O systems.

关键词： carbonyl group narrowband acceptor decoration thermally activated delayed fluorescence OLEDs