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Science China(Information Sciences) 2022年第2期65卷 254-256页

作者： Rui-Yang CAI hua-cheng zhou Chun-Hai KOU College of Information Science and Technology Donghua University School of Mathematics and Statistics Central South University Department of Applied Mathematics Donghua University

Dear editor,Fractional systems have been identified as an excellent tool for describing sub-diffusion phenomena owing to the memory property of the fractional derivatives.Among all the research fields in the control theory of fractional systems,stabilization occupies an important place.Ref.[1]discussed the boundary stabilization for fractional PDEs (partial differential equations) for the first time,where a feedback controller was designed to stabilize fractional wave equations using numerical methods,

关键词： Boundary control active disturbance rejection control backstepping method fractional Mittag-Leffler stable

Controllability of fractional-order damped systems with time-varying delays in control

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Frontiers of Information Technology & Electronic Engineering 2020年第6期21卷 844-855页

作者： Bin-bin HE hua-cheng zhou Chun-hai KOU College of Urban Railway Transportation Shanghai University of Engineering ScienceShanghai 201620China School of Mathematics and Statistics Central South UniversityChangsha 410075China Department of Applied Mathematics Donghua UniversityShanghai 201620China

In this study,we focus on the controllability of fractional-order damped systems in linear and nonlinear cases with multiple time-varying delays in control.For the linear system based on the Mittag-Leffler matrix function,we define a controllability Gramian matrix,which is useful in judging whether the system is controllable or not.Furthermore,in two special cases,we present serval equivalent controllable conditions which are easy to verify.For the nonlinear system,under the controllability of its corresponding linear system,we obtain a sufficient condition on the nonlinear term to ensure that the system is controllable.Finally,two examples are given to illustrate the theory.

关键词： Controllability Fractional-order damped systems Time-varying delays Gramian matrix

On the convergence of tracking differentiator with multiple stochastic disturbances

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Science China(Information Sciences) 2024年第2期67卷 157-169页

作者： Zehao WU huacheng zhou Baozhu GUO Feiqi DENG School of Mathematics and Big Data Foshan University School of Mathematics and Statistics Central South University Academy of Mathematics and Systems Science Chinese Academy of Sciences Systems Engineering Institute South China University of Technology

This paper investigates the convergence, noise-tolerance, and filtering performance of a tracking differentiator in the presence of multiple stochastic disturbances for the first time. We consider a general case wherein the input signal is corrupted by additive colored noise, and the tracking differentiator is disturbed by additive colored noise and white noise. The tracking differentiator is shown to track the input signal and its generalized derivatives in the mean square sense. Further, the almost sure convergence can be achieved when the stochastic noise affecting the input signal is vanishing. Herein, numerical simulations are performed to validate the theoretical results.

关键词： tracking differentiator convergence noise-tolerance filtering performance multiple stochastic disturbances

Reliability of a Multicomponent Stress-strength Model Based on a Bivariate Kumaraswamy Distribution with Censored Data

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 478-507页

作者： Cong-hua cheng School of Mathematics and Statistics Zhaoqing UniversityZhaoqing 526061China

In this paper,we consider a system which has k statistically independent and identically distributed strength components and each component is constructed by a pair of statistically dependent elements with doubly type-II censored scheme.These elements(X1,Y1),(X2,Y2),…,(Xk,Yk)follow a bivariate Kumaraswamy distribution and each element is exposed to a common random stress T which follows a Kumaraswamy distribution.The system is regarded as operating only if at least s out of k(1≤s≤k)strength variables exceed the random stress.The multicomponent reliability of the system is given by Rs,k=P(at least s of the(Z1,…,Zk)exceed T)where Zi=min(Xi,Yi),i=1,…,k.The Bayes estimates of Rs,k have been developed by using the Markov Chain Monte Carlo methods due to the lack of explicit forms.The uniformly minimum variance unbiased and exact Bayes estimates of Rs,k are obtained analytically when the common second shape parameter is known.The asymptotic confidence interval and the highest probability density credible interval are constructed for Rs,k.The reliability estimators are compared by using the estimated risks through Monte Carlo simulations.

关键词： stress-strength model bivariate Kumaraswamy distribution multicomponent reliability doubly Type-II censored scheme interval estimation

Triple reverse order law for the Drazin inverse

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 55-68页

作者： WANG hua ZHONG cheng-cheng College of Sciences Inner Mongolia University of TechnologyHohhot 010051China College of Engineering University of Jinan Quancheng CollegeYantai 265600China

In this paper,we investigate the reverse order law for Drazin inverse of three bound-ed linear operators under some commutation relations.Moreover,the Drazin invertibility of sum is also obtained for two bounded linea... 详细信息

关键词： Drazin inverse reverse order law space decomposition

Hydrophobic long-chain two-dimensional perovskite scintillators for underwater X-ray imaging

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Rare Metals 2024年第1期43卷 175-185页

作者： Jin-Xiao Zheng Zi-An zhou Tiao Feng Hui Li cheng-hua Sun NüWang Yang Tian Yong Zhao Shu-Yun zhou Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Laboratory of Bioinspired Smart Interfacial Science and Technology of the Ministry of Education Beijing Key Laboratory of Bioinspired Energy Materials and DevicesSchool of ChemistryBeijing Advanced Innovation Center for Biomedical EngineeringBeihang UniversityBeijing 100191China Department of Engineering Physics Tsinghua University and Key Laboratory of Particle and Radiation Imaging Ministry of EducationTsinghua UniversityBeijing 100084China e-mail:yangt@***

The underwater X-ray imaging technology development is significant to subaqueous target reconnaissance/detection/identification, subfluvial archaeology,submerged resource exploration, etc. As the core of X-ray imaging detection, the scintillator has been plagued by inherent moisture absorption and decomposition, and strict requirements for seamless packaging and waterproofing.Here, we designed a manganese-doped two-dimensional(2D) perovskite scintillator modified by hydrophobic longchain organic amine through the combination of component and doping engineering. The modified perovskites show high water repellency that can be used as an underwater X-ray scintillator. X-ray images of aquatic organisms or other objects with a high spatial resolution of10 lp·mm^(-1) at a big view field(32 mm × 32 mm) were obtained by scintillation screen. This hydrophobic perovskite scintillator based on molecular design is of great promise in underwater X-ray nondestructive testing technology development.

关键词： Two-dimensional perovskite Hydrophobic Scintillators Underwater X-ray imaging Underwater nondestructive testing technology

Effects of plants-associated microbiota on cultivation and quality of Chinese herbal medicines

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Chinese Herbal Medicines 2024年第2期16卷 190-203页

作者： Yue Ouyang Qiqing cheng Chunsong cheng Ziyu Tang Yufeng huang Eyu Tan Shaofeng Ma Xinheng Lin Ying Xie hua zhou Guangdong Provincial Hospital of Chinese Medicine Guangdong Provincial Academy of Chinese Medical SciencesState Key Laboratory of Dampness Syndrome of Chinese MedicineSecond Affiliated Hospital of Guangzhou University of Chinese MedicineGuangdong-Hong Kong-Macao Joint Lab on Chinese Medicine and Immune Disease ResearchGuangzhou 510006China Faculty of Chinese Medicine Macao University of Science and TechnologyMacao 999078China School of Pharmacy Hubei University of Science and TechnologyXianning 437100China Key Laboratory of Plant Ex-situ Conservation and Research Center of Resource Plant Lushan Botanical GardenChinese Academy of SciencesJiujiang 332900China Jiangmen Wuyi Hospital of Traditional Chinese Medicine Jiangmen 529020China Joint Laboratory for Translational Cancer Research of Chinese Medicine Ministry of EducationGuangzhou University of Chinese MedicineGuangzhou 510006China

Microbial resource influences the life activities of medicinal plants from several perspectives.Endophytes,rhizosphere microorganisms,and other environmental microorganisms play essential roles in medicinal plant growth and development,plant yield,and clinical efficacy.The microbiota can influence the biosynthesis of active compounds in medicinal plants by stimulating specific metabolic pathways.They induce host plants to improve their resistance to environmental stresses by accumulating secondary metabolites.Microorganisms can interact with their host plants to produce long-term,targeted selection results and improve their ability to adapt to the environment.Due to the interdependence and interaction between microorganisms and medicinal plants,Chinese herbal medicines(CHMs)quality is closely related to the associated microorganisms.This review summarizes the relationship between medicinal plants and their associated microorganisms,including their species,distribution,life activities,and metabolites.Microorganisms can aid in quality control,improve the efficacy of medicinal plants,and provide markers for identifying the origin and storage time of CHMs.Therefore,a comprehensive understanding of the relationship between microorganisms and medicinal plants will help to control the quality of CHMs from different perspectives.

关键词： Chinese herbal medicines endophytes environmental microorganisms microbiota rhizosphere microorganisms

Learnware:small models do big

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Science China(Information Sciences) 2024年第1期67卷 39-50页

作者： Zhi-hua zhou Zhi-Hao TAN National Key Laboratory for Novel Software Technology Nanjing University

There are complaints about current machine learning techniques such as the requirement of a huge amount of training data and proficient training skills,the difficulty of continual learning,the risk of catastrophic forgetting,and the leaking of data privacy/proprietary.Most research efforts have been focusing on one of those concerned issues separately,paying less attention to the fact that most issues are entangled in practice.The prevailing big model paradigm,which has achieved impressive results in natural language processing and computer vision applications,has not yet addressed those issues,whereas becoming a serious source of carbon emissions.This article offers an overview of the learnware paradigm,which attempts to enable users not to need to build machine learning models from scratch,with the hope of reusing small models to do things even beyond their original purposes,where the key ingredient is the specification which enables a trained model to be adequately identified to reuse according to the requirement of future users who know nothing about the model in advance.

关键词： artificial intelligence machine learning learnware

Evaluation of the value of combined detection of tumor markers CA724,carcinoembryonic antigen,CA242,and CA19-9 in gastric cancer

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1737-1744页

作者： Chong-Mei zhou Shao-hua Zhao Department of Clinical Laboratory Henan Provincial People's HospitalZhengzhou 450003Henan ProvinceChina

BACKGROUND Gastric cancer is a global health concern that poses a significant threat to human well-being.AIM To detecting serum changes in carcinoembryonic antigen(CEA),carbohydrate antigens(CA)724,CA242,and CA19-9 expression among patients with gastric cancer.METHODS Eighty patients diagnosed with gastric cancer between January 2020 and January 2023 were included in the observation group,while 80 patients with benign gastric diseases were included in the control group.Both groups were tested for tumor markers(CA724,CEA,CA242,and CA19-9].Tumor marker indicators(CA724,CEA,CA242,and CA19-9)were compared between the two groups,assessing positive rates of tumor markers across various stages in the observation group.Additionally,single and combined detection of various tumor markers were examined.RESULTS The sensitivity,specificity,accuracy,positive predictive value,and negative predictive value observed for the combined detection of CA724,CEA,CA242,and CA19-9 were higher than those of CA724,CEA,CA242,and CA19-9 individually.Therefore,the combined detection of CA724,CEA,CA242,and CA19-9 has a high diagnostic accuracy and could reduce the occurrence of missed or misdiagnosed cases,facilitating the early diagnosis and treatment of patients.CONCLUSION CA724,CEA,CA242,and CA19-9 serum levels in gastric cancer patients significantly surpassed those in non-gastric cancer patients(P<0.05).Their combined detection can improve the diagnostic accuracy for gastric cancer,warranting clinical promotion.

关键词： Biomarkers Serum Gastric cancer Diagnostic value

Investigating the Mechanism of Qu Du Qiang Fei 1 Hao Fang Formula against Coronavirus Disease 2019 Based on Network Pharmacology Method

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World Journal of Traditional Chinese Medicine 2024年第1期10卷 93-103页

作者： Yuan-hua Wang He-Yang zhou Jin-Yun Ma Gui-Qing Ding hua Yu Yong-Sheng Jin Xiao-Dong cheng Institute of Clinical Immunology Yue-Yang Hospital of Integrative MedicineShanghai University of Traditional Chinese MedicineShanghaiChina School of Pharmacy Naval Medical UniversityShanghaiChina

Objective:Qu Du Qiang Fei 1 Hao Fang(QDQF1)is a novel Chinese herbal medicine formula used to treat coronavirus disease 2019(COVID-19).However,the pharmacological mechanisms of action of QDQF1 remain unclear.The objective of this study was to identify the effective ingredients and biological targets of QDQF1 for COVID-19 treatment.Materials and Methods:The effective ingredients and mechanisms of action of QDQF1 were analyzed by using network pharmacology methods,which included an analysis of the effective ingredients and corresponding targets,COVID-19-related target acquisition,compound-target network analyses,protein-protein interaction network analysis,Kyoto Encyclopedia of Genes and Genomes(KEGG)and Gene Ontology(GO)enrichment analyses,and molecular docking studies.Results:In total,288 effective QDQF1 ingredients were identified.We identified 51 core targets from the 148 targets through an overlap between putative QDQF1 targets and COVID-19-related targets.Six key components,including formononetin,kaempferol,luteolin,naringenin,quercetin,and wogonin were identified through component-target network analyses.GO functional enrichment analysis of the core targets revealed 1296 items,while KEGG pathway enrichment analysis identified 148 signaling pathways.Nine central targets(CCL2,CXCL8,IL1B,IL6,MAPK1,MAPK3,MAPK8,STAT3,and TNF)related to the COVID-19 pathway were identified in the KEGG pathway enrichment analysis.Furthermore,molecular docking analysis suggested that the docking scores of the six key components to the nine central targets were better than those to remdesivir.Conclusions:QDQF1 may regulate multiple immune-and inflammation-related targets to inhibit the progression of severe acute respiratory syndrome coronavirus 2,and thus,may be suitable for the treatment of COVID-19.

关键词： Coronavirus disease 2019 molecular docking molecular mechanism network pharmacology Qu Du Qiang Fei 1 Hao Fang formula