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Asynchronous control for 2-D Markov jump cyber-physical systems against aperiodic denial-of-service attacks

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Science China(Information Sciences) 2023年第7期66卷 195-209页

作者： Peng CHENG Di WU Shuping HE weidong zhang Department of Automation Shanghai Jiao Tong University School of Electrical Engineering and Automation Anhui University

This work focuses on the asynchronous controller design for two-dimensional Markov jump cyberphysical systems against denial-of-service attacks. Firstly, due to the openness of the network, it is vulnerable to cyber-attacks, resulting in the control input signal may not being sent to the designated location. Meanwhile, considering the influence of transmission delays and unavoidable packet dropout, a hidden Markov model can help to deal with the unavoidable asynchronous phenomenon between the plant mode and the controller mode. Then, by introducing the concepts of time instants and global states into two-dimensional systems, an asynchronous control scheme for two-dimensional Markov jump cyber-physical systems is successfully formulated. Subsequently, recurring to the multi-Lyapunov function method and iterative technology,sufficient conditions are achieved to make sure that the dynamic hidden two-dimensional Markov jump cyberphysical systems are asymptotically mean-square stable. To conclude, an application example related to the metal rolling process is provided to illustrate the feasibility and effectiveness of the presented asynchronous control scheme under aperiodic denial-of-service attacks.

关键词： asynchronous two-dimensional Markov jump cyber-physical systems denial-of-service attacks hidden Markov model

Priming effect and its regulating factors for fast and slow soil organic carbon pools: A meta-analysis

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Pedosphere 2022年第1期32卷 140-148页

作者： Changfu HUO Junyi LIANG weidong zhang Peng WANG Weixin CHENG Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China Department of Grassland Resources and Ecology College of Grassland Science and TechnologyChina Agricultural UniversityBeijing 100083China Environmental Studies Department University of CaliforniaSanta Cruz CA 95064USA

The priming effect (PE) plays a critical role in the control of soil carbon (C) cycling and influences the alteration of soil organic C (SOC) decomposition by fresh C input.However,drivers of PE for the fast and slow SOC pools remain unclear because of the varying results from individual studies.Using meta-analysis in combination with boosted regression tree (BRT) analysis,we evaluated the relative contribution of multiple drivers of PE with substrate and their patterns across each driver gradient.The results showed that the variability of PE was larger for the fast SOC pool than for the slow SOC pool.Based on the BRT analysis,67%and 34%of the variation in PE were explained for the fast and slow SOC pools,respectively.There were seven determinants of PE for the fast SOC pool,with soil total nitrogen (N) content being the most important,followed by,in a descending order,substrate C:N ratio,soil moisture,soil clay content,soil pH,substrate addition rate,and SOC content.The directions of PE were negative when soil total N content and substrate C:N ratio were below 2 g kg~(-1)and 20,respectively,but the directions changed from negative to positive with increasing levels of this two factors.Soils with optimal water content (50%–70%of the water-holding capacity) or moderately low pH (5–6) were prone to producing a greater PE.For the slow SOC pool,soil p H and soil total N content substantially explained the variation in PE.The magnitude of PE was likely to decrease with increasing soil pH for the slow SOC pool.In addition,the magnitude of PE slightly fluctuated with soil N content for the slow SOC pool.Overall,this meta-analysis provided new insights into the distinctive PEs for different SOC pools and indicated knowledge gaps between PE and its regulating factors for the slow SOC pool.

关键词： boosted regression tree fresh C input recalcitrant carbon soil carbon cycling soil carbon mineralization soil moisture soil nitrogen content soil organic carbon

B-GQDs@GSH as a Highly Selective and Sensitive Fluorescent Probe for the Detection of Fe^(3+) in Water Samples and Intracellular

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Journal of Analysis and Testing 2023年第2期7卷 147-156页

作者： Xiaohua Yang Peigang zhang Jie Tan Xuebing Li weidong zhang Wei Bian Martin M.F.Choi Department of Biochemistry and Molecular Biology School of Basic Medical ScienceShanxi Medical UniversityTaiyuan 030001China Lvliang People’s Hospital Lvliang 033000China Department of Traditional Chinese Medicine the First Hospital of Shanxi Medical UniversityTaiyuan 030001China

Owing to the excellent stability,biocompatibility and photoluminescence property,graphene quantum dots(GQDs)are emerging as a kind of potential materials to be applied in a series of fields ranging from sensor to drug delivery.As the growing concern for human and environmental safety,selective detection of metal ions has been paid more and more attention.GQDs,as nanoparticles with superior optical properties,have been attracting growing attention in the field of metal ions detection.In this work,glutathione(GSH)functionalized boron doped graphene quantum dots(B-GQDs@GSH)were successfully synthesized with stable bright blue fluorescence and has been used for the detection of Fe^(3+).A good linear relationship between 1/(F_(0)-F)and 1/c with the concentration ranging from 0.70 to 53μmol/L was obtained with a detection limit of 5.5 nmol/L.The application of B-GQDs@GSH for Fe^(3+)detection in water samples was demonstrated and the quenching mechanism was further explored.Due to low cytotoxicity and favorable biocompatibility,B-GQDs@GSH were successfully applied for cell fluorescence imaging and intracellular determination of Fe^(3+).

关键词： Fluorescence probe Quenching mechanism Real samples detection Intracellular detection

一种基于EGK-均值聚类和PCA的海流发电机叶片冲击故障检测方法

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太阳能学报 2024年第3期45卷 201-209页

作者：谢涛张卫东张义博上海交通大学电子信息与电气工程学院上海200240

海流发电机受海流流速变化、随机湍流的影响呈现多变工况,想要准确检测出叶片冲击故障是一项巨大挑战。基于此,提出一种基于包络几何特征聚类(EGK-均值聚类)的方法用于划分变工况下产生的定子电流信号,在不同子工况下建立故障检测模型... 详细信息

海流发电机受海流流速变化、随机湍流的影响呈现多变工况,想要准确检测出叶片冲击故障是一项巨大挑战。基于此,提出一种基于包络几何特征聚类(EGK-均值聚类)的方法用于划分变工况下产生的定子电流信号,在不同子工况下建立故障检测模型。首先,根据样本矩阵构建包络几何特征矩阵,利用几何特征矩阵确定初始聚类中心进行聚类;然后,基于各工况下的包络数据分别进行主元分析以降低数据维度;最后,T^(2)和SPE统计量被计算用于实时冲击故障检测。一台海流发电机样机及配套循环水槽被搭建验证本文所提方法。实验结果表明本文所提方法在变工况下针对海流发电机叶片冲击故障有着显著的识别能力和检测精度。

关键词：海洋能海洋工程信号处理聚类算法故障检测主成分分析

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Food-derived bioactive peptides:production,biological activities,opportunities and challenges

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Journal of Future Foods 2022年第4期2卷 294-306页

作者： Hedan Ye Xin Tao weidong zhang Yi Chen Qiang Yu Jianhua Xie State Key Laboratory of Food Science and Technology Nanchang UniversityNanchang 330047China

Bioactive peptides(BPs)are multifunctional compounds derived from proteins,which exhibit different functions and show significant pharmacological effects.In the past few decades,the study on food-derived BPs had never been interrupted,and a wide range of BPs sequences have been identified due to its wide range of health benefit and multiple bioactivities,such as antioxidant,immune activity,anti-aging,anti-inflammatory activities.The bioactivities of BPs are mainly depend on the amino acid composition,size,sequence and physicochemical properties.What's more,BPs is reasonable and feasible as functional foods and pharmaceutical preparations to promote human health for its advantages of high safety,rich source,obvious physiological effect and easy digestion and absorption.However,there are many obstacles that limit the development of BPs.This review mainly summarizes the preparation methods,biological properties and applications of food-derived BPs.The opportunities and challenges of food-derived BPs as functional products are also disscussed.This review may provide a reference for the further utilization,deep processing and commercial development of food derived BPs.

关键词： Peptides Preparation Bioactivity Opportunities Challenges

Allocation patterns of nonstructural carbohydrates in response to CO_(2)elevation and nitrogen deposition in Cunninghamia lanceolata saplings

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Journal of Forestry Research 2023年第1期34卷 87-98页

作者： Wenhui Zheng Renshan Li Qingpeng Yang weidong zhang Ke Huang Xin Guan Longchi Chen Xin Yu Qingkui Wang Silong Wang Fujian Provincial Key Laboratory of Resources and Environmental Monitoring and Sustainable Management and Utilization Sanming UniversitySanming 365004People’s Republic of China CAS Key Laboratory of Forest Ecology and Management Institute of Applied EcologyHuitong Experimental Station of Forest EcologyShenyang 110016People’s Republic of China Huitong National Research Station of Forest Ecosystem HuaihuaHuitong 418307People’s Republic of China Life Science Department Luoyang Normal UniversityLuoyang 471934People’s Republic of China Fujian Provincial Key Laboratory of the Development and Utilization of Bamboo Resources Sanming UniversitySanming 365004People’s Republic of China

Stored nonstructural carbohydrates(NSC)indicate a balance between photosynthetic carbon(C)assimilation and growth investment or loss through respiration and root exudation.They play an important role in plant function and whole-plant level C cycling.CO_(2)elevation and nitrogen(N)deposition,which are two major environmental issues worldwide,aff ect plant photosynthetic C assimilation and C release in forest ecosystems.However,information regarding the eff ect of CO_(2)elevation and N deposition on NSC storage in diff erent organs remains limited,especially regarding the trade-off between growth and NSC reserves.Therefore,here we analyzed the variations in the NSC storage in diff erent organs of Chinese fi r(Cunninghamia lanceolata)under CO_(2)elevation and N addition and found that NSC concentrations and contents in all organs of Chinese fi r saplings increased remarkably under CO_(2)elevation.However,N addition induced diff erential accumulation of NSC among various organs.Specifi cally,N addition decreased the NSC concentrations of needles,branches,stems,and fi ne roots,but increased the NSC contents of branches and coarse roots.The increase in the NSC contents of roots was more pronounced than that in the NSC content of aboveground organs under CO_(2)elevation.The role of N addition in the increase in the structural biomass of aboveground organs was greater than that in the increase in the structural biomass of roots.This result indicated that a diff erent tradeoff between growth and NSC storage occurred to alleviate resource limitations under CO_(2)elevation and N addition and highlights the importance of separating biomass into structural biomass and NSC reserves when investigating the eff ects of environmental change on biomass allocation.

关键词： Biomass partition CO_(2)elevation N deposition Nonstructural carbohydrates Structural biomass

Exceptional points and enhanced nanoscale sensing with a plasmon-exciton hybrid system

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Photonics Research 2022年第2期10卷 557-563页

作者： Hong Jiang weidong zhang Guowei Lu Lulu Ye Hai Lin Jinglin Tang Zhaohang Xue Zheng Li Haitan Xu Qihuang Gong State Key Laboratory for Mesoscopic Physics Collaborative Innovation Center of Quantum MatterNano-optoelectronics Frontier Center of the Ministry of EducationSchool of PhysicsPeking UniversityBeijing 100871China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China Peking University Yangtze Delta Institute of Optoelectronics Nantong 226010China Shenzhen Institute for Quantum Science and Engineering Southern University of Science and TechnologyShenzhen 518055China School of Physical Sciences University of Science and Technology of ChinaHefei 230026China

Singularities in the spectra of open systems, known as exceptional points(EPs), have been shown to exhibit nontrivial topological properties and enhanced sensitivities. Here, we propose a novel approach to realize the EPs in a plasmon-exciton hybrid system and explore their applications in enhanced nanoscale sensing technology.We consider a plasmon-exciton system composed of a gold nanorod and a monolayer WSe_(2). By controlling the geometric parameters of the nano-hybrid system, we obtain simultaneous coalescence of the resonance frequencies and loss rates of the hybrid system, which is a unique feature of EPs. Numerical simulations show its application in enhanced nanoscale sensing for environmental refractive indices. Our work opens the way to a new class of sensors based on EP-enhanced sensing, with intrinsic nanoscale sensitivity due to the sub-diffractionlimit size of the plasmon-exciton nano-hybrid system.

关键词： system plasmon points

Nature of CoCrFeMnNi/Fe and CoCrFeMnNi/Al Solid/Solid Interface

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Acta Metallurgica Sinica(English Letters) 2021年第11期34卷 1483-1491页

作者： Zhongtao Li weidong zhang Zhenggang Wu College of Materials Science and Engineering Hunan UniversityChangsha 410082China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan UniversityChangsha 410082China

To shed light into the application potential of high-entropy alloys as"interlayer"materials for Al-steel solid-state joining,we investigated the nature of the CoCrFeMnNi/Fe and CoCrFeMnNi/Al solid/solid interfaces,focusing on the bonding behavior and phase components.Good metallurgical bonding without the formation of hard and brittle IMC can be achieved for CoCrFeMnNi/Fe solid/solid interface.In contrast to the formation of Al5 Fe2 phase at the Fe/Al interface,Al13Fe4-type IMC,in which the Fe site is co-occupied equally by Co,Cr,Fe,Mn and Ni,dominates the CoCrFeMnNi/Al interface.Although the formation of IMC at the CoCrFeMnNi/Al interface is not avoidable,the thickness and hardness of the Al13(CoCrFeMnNi)4 phase formed at the CoCrFeMnNi/Al interface are significantly lower than the Al5 Fe2 phase formed at the Fe/Al interface.The activation energies for the interdiffusion of Fe/Al and CoCrFeMnNi/Al static diffusion couple are 341.6 kJ/mol and 329.5 kJ/mol,respectively.Despite this similarity,under identical static annealing condition,the interdiffusion coe fficient of the CoCrFeMnNi/Al diffusion couple is significantly lower than that of the Fe/Al diffusion couple.This is thus mainly a result of the reduced atomic mobility/diffusivity caused by the compositional complexity in CoCrFeMnNi high-entropy alloy.

关键词： High-entropy alloy Microstructure Metallurgical bonding Interface

Adsorption equilibrium and the effect of honeycomb heat exchanging device on charge/discharge characteristic of methane on MIL-101(Cr)and activated carbon

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Chinese Journal of Chemical Engineering 2020年第7期28卷 1964-1972页

作者： Guobin Zhao Qingrong Zheng Xuan zhang weidong zhang Provincial Key Laboratory of Naval Architecture&Ocean Engineering Institute of Marine EngineeringJimei UniversityXiamen 361021China

Experiments were conducted for developing suitable ANG adsorbents for vehicular applications.MIL-101 and activated carbon samples were respectively prepared by hydrothermal and chemical activation methods.Two samples were undergone structure analysis on adsorption data of nitrogen at 77.15 K,and adsorption data of methane were then volumetrically measured within temperature-pressure range 293.15 K-313.15 K and 0-8 MPa.A conformable vessel in volume 2.5 L was employed for charge/discharge tests under the flow rate 10-30 L·min^-1.It shows that limit isostreic heat of methane adsorption is respectively about 25.15 k J·mol^-1 and22.94 k J·mol^-1 on the activated carbon and the MIL-101,and isosteric heat within the experimental condition is 14-19.5 k J·mol^-1;employing a smaller charge/discharge flow rate can weaken the temperature fluctuation of the adsorbent bed and increase the charge/discharge amount;employing honeycomb heat exchanging device enhance the thermal conductivity of the adsorbent bed by consuming a negligible part of volume of the vessel.It suggests that a smaller flow rate for charge/discharge should be employed,and MOFs together with the honeycomb heat exchanging device are promising for practical applications.

关键词： Natural gas MOFs Activated carbon Adsorption