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控制方向未知的受限多智能体系统的预设时间模糊控制

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工程科学学报 2025年第1期47卷 121-129页

作者：李菲周超范利蓉王芳燕山大学理学院秦皇岛066004 河北农业大学海洋学院秦皇岛066003

综合考虑受控制方向未知、输入受限和状态时延影响的有领导者多智能体系统的编队控制问题,设计基于模糊逻辑系统的预设时间一致性控制策略.为了保证编队输出误差在预设时间内满足预定的约束范围要求,引入预设时间性能函数,构造Lyapunov-... 详细信息

综合考虑受控制方向未知、输入受限和状态时延影响的有领导者多智能体系统的编队控制问题,设计基于模糊逻辑系统的预设时间一致性控制策略.为了保证编队输出误差在预设时间内满足预定的约束范围要求,引入预设时间性能函数,构造Lyapunov-Krasovskii(L-K)泛函解决状态时延问题,将外界干扰和L-K泛函的导数中的部分项定义为未知非线性函数,并利用模糊逻辑系统对其进行估计,利用Nussbaum函数和均值定理分别处理控制方向未知和输入受限问题,基于以上设计,提出预设时间模糊控制策略,并通过Lyapunov稳定性理论,分析闭环系统的有界稳定性,数值对比仿真和两级化学反应器应用仿真说明控制方法的有效性.

关键词：多智能体系统状态时延输出误差约束输入受限控制方向未知

Applications of nanomaterials in COVID-19 pandemic

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Rare Metals 2022年第1期41卷 1-13页

作者： Mei-fang Xiao chang Zeng Shao-Hui li Fu-Lai Yuan Health Management Center Xiangya HospitalCentral South UniversityChangsha 410008China

The novel coronavirus 2019(COVID-19)pandemic represents one of the biggest global health threats in the last two decades,so researchers around the world are searching for solutions and treatments for *** the time of writing,there are no specific drugs that have demonstrated suitable effectiveness in treating *** current challenge involves designing tools for the prevention,rapid and accurate diagnosis,drug delivery,and effective treatment of this novel *** this short review,we discuss how nanotechnology offers new ways to combat COVID-19,and how nanomaterials can be applied to control the COVID-19 *** also summarize relevant studies regarding the use of nanomaterials for preventing viral spread,preparing vaccines,and diagnosing coronavirus,as well as studies that show how nanoparticles can be used as drug delivery systems for the treatment of viral *** on nanotechnology-based diagnosis,drug delivery,and antiviral therapy is currently in the early ***,the unique chemical properties of some nanomaterials highlight the broad prospect of nanomaterials in the future,and we propose that they will play an important role in the fight against COVID-19.

关键词： Coronaviruses COVID-19 Nanomaterials Viral control

Joint Optimization Scheme Based on Beam Selection and Interference Cancellation in Lens Millimeter Wave NOMA Systems

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China Communications 2022年第4期19卷 57-66页

作者： Lei Xu Jing Cai Jing chang Hongyu fang Xiaohui li School of Electronics and Information Engineering Anhui UniversityHefei 230601China

Non-orthogonal multiple access(NOMA)has been integrated in millimeter-wave(mmWave)Massive MIMO systems to further enhance the spectrum efficiency, but NOMA has not been fully considered in lens mmWave systems. The fusion of these two technologies requires the joint design of beam selection and interference cancellation. In addition, when users follow the spatial cluster distribution, although the user clustering schemes based on K-means algorithm have been applied, the influence of the virtual and actual cluster center users on achievable sum rate has not been differentiated and analyzed in detail. To solve the above problems, a joint optimization scheme is proposed to maximize the achievable sum rate. The optimization problem is NP-hard, which is solved by using the divide-and-conquer approach. Concretely,based on the signal power loss analysis of directional deviation, a beam selection algorithm is designed for inter-cluster interference cancellation based on the Kmeans algorithm. Further for intra-cluster interference cancellation, a power allocation algorithm based on the bisection method is designed to guarantee the fairness of users in each cluster. The simulation results show that the proposed scheme offers a significant performance improvement in terms of both achievable sum rate and energy efficiency, and it is suitable for the large-scale user scenario due to its low complexity.

关键词： lens mmWave systems NOMA user clustering beam selection power allocation

Evaluation on the natural gas hydrate formation process

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Chinese Journal of Chemical Engineering 2020年第3期28卷 881-888页

作者： Shuqi fang Xinyue Zhang Jingyi Zhang Chun chang Pan li Jing Bai School of Chemical Engineering and Energy Zhengzhou UniversityZhengzhou 450001China Henan Outstanding Foreign Scientists'Workroom Zhengzhou 450001China Engineering Laboratory of Henan Province for Biorefinery Technology and Equipment Zhengzhou 450001China

Gas hydrates have endowed with great potential in gas storage,and rapid formation of gas hydrates is critical to use this novel *** work evaluated the natural gas hydrate formation process,which was compared from six parameters,including conversion of water to hydrate,storage capacity,the rate of hydrate formation,space velocity(SV)of hydrate reaction,energy consumption and hydrate *** literature was selected by analyzing and comparing these six parameters mentioned above,meanwhile placing emphasis on the three parameters of storage capacity,the rate of hydrate formation and space velocity of hydrate *** analysis and comparison,four conclusions could be obtained as ***,the overall performance of the stirring process and the spraying process were better than other processes after analyzing the six ***,the additive types,the reactor structure and the reactor size had influence on the natural gas hydrate formation ***,the energy consumption via reciprocating impact in the hydrate formation process was higher than that via stirring,spraying and static ***,it was one key for hydrate removal to realize the hydrate industrial production.

关键词： Natural gas hydrate Evaluate Hydrate formation process Storage capacity Space velocity of hydrate reaction

Effect of Noncontact Ultrasonic Technology on Solidification Quality of Electroslag Steel

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Journal of Iron and Steel Research International 2016年第11期23卷 1168-1176页

作者： Xiao-fang SHI li-zhong chang Zheng-hai ZHU Jian-jun WANG li ZHOU School of Metallurgy Engineering Anhui University of Technology

A new electroslag furnace with ultrasonic vibration introduced through water-cooled base plate was de- signed and the effects of ultrasonic power on the distribution of elements, compactness and carbides in the electroslag remelting （ESR） ingots was investigated. The results showed that the distribution of elements on the entire excita- tion section changed with the change of ultrasonic power under experimental conditions. The statistical segregation of elements was minimum when the ultrasonic power was 500 W, whereas excessively high or excessively low power was not conducive to the uniform distribution of elements. Meanwhile, the compactness of ESR ingots gradually in- creased with the increase in ultrasonic power and distribution of compactness was the most uniform when ultrasonic power reached 500 W. Further increase in the ultrasonic power was not conducive to the improvement of compactness. The distribution characteristic of carbides was similar to the distribution of elements and compactness. The re- sults indicated that the ultrasonic vibration introduced through water-cooled base plate was advantageous in impro- ving solidification quality. However, this method needed reasonable ultrasonic power. Moreover, the effects of ultra- sonic power varied for different elements.

关键词： ultrasonic eleetroslag remelting solidification element distribution carbide

Micro-strain regulation strategy to stabilize perovskite lattice based on the categories and impact of strain on perovskite solar cells

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Journal of Energy Chemistry 2025年第1期100卷 578-604页

作者： Caixia li Wenwu liu Shiji Da lingbin Kong Fen Ran State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of Technology School of Materials Science and Engineering Lanzhou University of Technology

Photovoltaic metal halide perovskite solar cells(PSCs) convert light to electricity more efficiently than crystalline silicon cells, and the cost of materials used to make them is lower than that of silicon *** efficiency is not a core issue affecting the application of perovskite solar cells in special *** present, stability is the major technical encounters that hinders its further commercial development. Microstrain in PSCs is currently a significant factor responsible for the device's instability. Strain-induced ion migration is widely believed to accelerate perovskite degradation even when external stimuli are ***, it is imperative to study strain to enhance the stability of PSCs. This paper reviews recent developments to understand strain's origin and effect mechanisms on performance of PSCs, including ion migration,failure behavior, defect formation, and its effect on photoelectric properties, stability, and ***, several well-known strain management strategies are systematically introduced based on the strain effect mechanism and strain engineering on the film, providing more clues for further preparation with increased stability. The manipulation of external physical strain applied from films to entire devices has been extensively studied. Furthermore, recommendations for future research directions and chemical approaches have been provided. It is emphasized that strain engineering plays a crucial role in improving the efficiency and longevity of PSCs. Tensile strain causes rapid degradation, while moderate compressive strain and external strain control could improve properties and stability. Efforts should focus on controlling compressive strain to mitigate residual tensile strain and introducing it in a controlled manner. Future research endeavors may focus on exploring these pathways to improve the efficiency and lifespan of PSCs.

关键词： Halide perovskite solar cells Strain origins Strain effects Strain management

Cryptococcus infection with asymptomatic diffuse pulmonary disease in an immunocompetent patient:A case report

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World Journal of Clinical Cases 2021年第11期9卷 2619-2626页

作者： Yong li Lei fang fang-Qun chang fang-Zhou Xu Yan-Bei Zhang Department of Geriatric Respiratory and Critical Care The First Affiliated Hospital of Anhui Medical UniversityHefei 230000Anhui ProvinceChina Department of Tuberculosis Anhui Medical University Clinical College of Chest&Anhui Chest HospitalHefei 230000Anhui ProvinceChina

BACKGROUND Cryptococcus presenting as an opportunistic pathogen mainly affects immunocompromised patients,but the disseminated form of infection is rare among immunocompetent *** partial radiographic characteristics of pulmonary cryptococcosis mimic lung carcinoma,leading to unnecessary open chest exploratory surgery,and the lack of a gold-standard noninvasive diagnostic increases the risk of *** emission tomography/computed tomography(PET/CT),a sensitive method for distinguishing malignant tumors,coupled with cryptococcal latex agglutination test showing a high positive rate may overcome these *** A 36-year-old man presented for general examination,without health *** CT showed multiple pulmonary nodules and a mass with high maximum standardized uptake ***,we suspected primary malignancy with hematogenous *** his routine fungal analysis had been negative,subsequent CT-guided percutaneous core needle biopsy and histopathology examination indicated a diagnosis of pulmonary ***(200 mg/d)antifungal drug treatment was initiated,and 1 mo later the pulmonary mass had reduced in size markedly(on chest CT scan)without any *** Serologic and PET/CT examinations may not rule out cryptococcosis,and percutaneous lung puncture is critical under all circumstances.

关键词： Cryptococcus Immunocompetent Positron emission tomography Computed tomography Cryptococcal latex agglutination test Lung diseases Fungal Case report

Effects of Cr and Mo elements on the microstructures and compressive properties of the in situ (TiCxNy–TiB2)/Ni cermets

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Progress in Natural Science:Materials International 2019年第1期29卷 20-27页

作者： fang chang Feng Qiu Chuanlu li Yawei Wang Qichuan Jiang State Key Laboratory of Automotive Simulation and Control Jilin University Key Laboratory of Automobile Materials Ministry of Education and Department of Materials Science and Engineering Jilin University

In-situ(TiCN–TiB)/Ni cermets with 70 wt%TiCN–TiBwere successfully fabricated by combustion synthesis and hot pressing sintering in Ni-Ti-BC-BN powder *** microstructures,density,compressive properties,and hardness of the TiCN–TiB/Ni cermets with the addition of 0–8 wt%Cr/Mo to the Ni-Ti-BC-BN powder systems were compared and *** results showed that the ceramic particles distributed uniformly in the cermets,and the size of the ceramic particles reduced with the Cr/Mo *** Cr and Mo addition can improve the hardness,compressive properties,and fracture strains of the *** hardness,compressive strength,and fracture strain of the(TiCN–TiB)/(Ni+Cr)cermets increased from 1561 HV,2.94 GPa,and 2.9%to 1864 HV,3.65 GPa,and 3.4%,respectively when the Cr content increased to 5 wt%.The hardness and compressive strength of the(TiCN–TiB)/(Ni+Mo)cermets increased from 1561 HV and 2.94 GPa to 1902 HV and 3.43 GPa,respectively when the Mo content increased to 8 wt%.The cermets with Cr had better compressive properties than the cermets with Mo.

关键词： (TiCxNy–TiB2)/Ni cermets Cr/Mo content Microstructure Compressive properties

Synthesis, Crystal Structure and Antibacterial Activities of 3-[(2-Hydroxy-4-diethylamino-phenyl)methylenehydrazinocarbonyl]-4-hydroxy-6-methyl-2(1H)-pyridinones

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Chinese Journal of Structural Chemistry 2006年第5期25卷 626-630页

作者： li fang PAN Fu-You YANG Jian-Guo GE chang-Hua Department of Chemistry Taizhou University Zhejiang 317000 China Office of Assets Administration Taizhou University Zhejiang 317000 China

The title compound C18H22N4O4 was synthesized by the reaction of 3-hydrazine-4-hydroxy-6-methyl-2（1H）-pyridinones with 2-hydroxy-4-diethylaminobenzaldehyde in ethanol and characteri- zed by IR, tH NMR and elemental analysis. The single-crystal structure has been determined by X-ray diffraction analysis. The crystal belongs to the triclinic system, space group P1^- with a = 10.1930（14）, b = 12.5200（17）, c = 15.1863（19） A, α= 96.292（3）, β= 96.450（3）, γ= 102.443（3）°, V= 1862.6（4） A^3, Z= 4, Mr = 358.40, μ = 0.092 mm^-1, D c= 1.278 g/cm^3, F（000） = 760 and R = 0.0803. The crystal structure involves intermolcular N-H…O as well as intramolcular O-H…N, O-H…O and N-H…O hydrogen bonds. The title compound shows no antibacterial activity.

关键词： 2(1H)-pyridinones X-ray diffraction crystal structure synthesis antibacterial activities