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Admissibility for Linear Estimator of Parameter on Growth Curve Model with Respect to Linear Constraint

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Acta Mathematicae Applicatae Sinica 2009年第1期25卷 171-176页

作者： Ming-xiang Cao fan-chao kong Department of Mathematics Hefei Teachers College Heifei 230061 China Department of Mathematics Anhui University Hefei 230038 China

By using the vector-method of matrix, we study Growth Curve Model with respect to linear constraint. Under matrix loss function and vector loss function, we obtain necessary and sufficient conditions for admissibility... 详细信息

关键词： Growth curve model linear estimators admissibility

General Admissibility for Linear Estimators in a General Multivariate Linear Model under Balanced Loss Function

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Acta Mathematica Sinica,English Series 2013年第9期29卷 1823-1832页

作者： Ming Xiang CAO fan chao kong Department of Mathematics Hefei Normal University School of Mathematics Anhui University

A generalization of Zellner’s balanced loss function is proposed. General admissibility in a general multivariate linear model is investigated under the generalized balanced loss function. And the sufficient and necessary conditions for linear estimators to be generally admissible in classes of homogeneous and nonhomogeneous linear estimators are given, respectively.

关键词： Balanced loss function linear estimators general optimality general admissibility

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

Test on Stochastic Block Model:Local Smoothing and Extreme Value Theory

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Journal of Systems Science & Complexity 2022年第4期35卷 1535-1556页

作者： WU fan kong Xinbing XU chao School of Mathematics Southeast UniversityNanjing211819China School of Statistics and Mathematics Nanjing Audit UniversityNanjing211815China School of Information Engineering Nanjing Audit UniversityNanjing211815China

In this paper,to obtain a consistent estimator of the number of communities,the authors present a new sequential testing procedure,based on the locally smoothed adjacency matrix and the extreme value *** the null hypothesis,the test statistic converges to the type I extreme value distribution,and otherwise,it explodes fast and the divergence rate could even reach n in the strong signal case where n is the size of the network,guaranteeing high detection *** method is simple to use and serves as an alternative approach to the novel one in Lei(2016)using random matrix *** detect the change of the community structure,the authors also propose a two-sample test for the stochastic block model with two observed adjacency *** studies justify the *** authors apply the proposed method to the political blog data set and find reasonable group structures.

关键词： Extreme value distribution network data stochastic block model

Rate of strong consistency of the maximum quasi-likelihood estimator in quasi-likelihood nonlinear models

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Applied Mathematics(A Journal of Chinese Universities) 2008年第4期23卷 391-400页

作者： XIA Tian kong fan-chao Dept. of Statist. Yunnan Univ. Kunming 650091 China Dept. of Math. Anhui Univ Hefei 230039 China

Quasi-likelihood nonlinear models （QLNM） include generalized linear models as a special case. Under some regularity conditions, the rate of the strong consistency of the maximum quasi-likelihood estimation （MQLE） is obtained in QLNM. In an important case, this rate is O（n-^1/2（loglogn）^1/2）, which is just the rate of LIL of partial sums for i.i.d variables, and thus cannot be improved anymore.

关键词： maximum quasi-likelihood estimator quasi-likelihood nonlinear models strong consistency

不稳定型心绞痛患者围术期心理分析及干预效果

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国际护理学杂志 2017年第4期36卷 535-537页

作者：王瑜范超孔繁晶秦迎迎首都医科大学附属北京安贞医院 100029

目的通过调查和分析不稳定型心绞痛患者围术期的焦虑状况,制定相应的心理护理干预方法,预防和减少术后并发症的发生,促进患者康复.方法选取348例诊断为不稳定型心绞痛并行择期介入治疗的患者,通过焦虑自评量表（self-rating anxietysc... 详细信息

目的通过调查和分析不稳定型心绞痛患者围术期的焦虑状况,制定相应的心理护理干预方法,预防和减少术后并发症的发生,促进患者康复.方法选取348例诊断为不稳定型心绞痛并行择期介入治疗的患者,通过焦虑自评量表（self-rating anxietyscale,SAS）测试调查,分为SAS＜50分患者与SAS≥50分患者组.两组患者又分别随机分为两个亚组,其中一组进行心理护理干预,另一组进行常规护理,分析心理护理干预对术后并发症发生率的影响.结果女性较男性SAS积分更高（61.1±10.9 vs 53.1±12.8,P=0.038）,更容易存在焦虑障碍;SAS≥50分患者的术后并发症发生率较于SAS＜50分患者更高（13.6%vs 25.1%,P=0.033）;对于SAS＜50分的患者,是否行心理护理干预对术后并发症发生率影响不大（11.1%vs 15.6%,P〉0.05）,而对SAS≥50分的患者心理护理干预可显著降低术后并发症的发生率（13.3%vs 37.1%,P＜0.01）.结论介入治疗围术期焦虑状态可显著影响不稳定型心绞痛患者介入治疗的预后,对焦虑患者应当加强心理护理,对预防和减少术后并发症的发生是十分有效的.

关键词：不稳定型心绞痛焦虑心理护理

Dynamic Interaction Analysis of Coupled Axial-Torsional-Lateral Mechanical Vibrations in Rotary Drilling Systems

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Structural Durability & Health Monitoring 2025年第1期19卷 77-103页

作者： Sabrina Meddah Sid Ahmed Tadjer Abdelhakim Idir kong Fah Tee Mohamed Zinelabidine Doghmane Madjid Kidouche Applied Automation Laboratory Faculty of Hydrocarbons and ChemistryUniversity of BoumerdesBoumerdes35000Algeria Institute of Electrical and Electronic Engineering(IGEE) University of BoumerdesBoumerdes35000Algeria Laboratory of the Electrification of Industrial Enterprises University of BoumerdesBoumerdes35000Algeria Electrical Engineering Department Mohamed Boudiaf University of M’silaM’sila28000Algeria Department of Civil and Environmental Engineering King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Interdisciplinary Research Center for Construction and Building Materials King Fahd University of Petroleum&Minerals(KFUPM)Dhahran31261Saudi Arabia

Maintaining the integrity and longevity of structures is essential in many industries,such as aerospace,nuclear,and *** achieve the cost-effectiveness of large-scale systems in petroleum drilling,a strong emphasis on structural durability and monitoring is *** study focuses on the mechanical vibrations that occur in rotary drilling systems,which have a substantial impact on the structural integrity of drilling *** study speciﬁcally investigates axial,torsional,and lateral vibrations,which might lead to negative consequences such as bit-bounce,chaotic whirling,and high-frequency *** events not only hinder the efﬁciency of drilling but also lead to exhaustion and harm to the system’s components since they are difﬁcult to be detected and controlled in real *** study investigates the dynamic interactions of these vibrations,speciﬁcally in their high-frequency modes,usingﬁeld data obtained from measurement while ***ﬁndings have demonstrated the effect of strong coupling between the high-frequency modes of these vibrations on drilling sys-tem *** obtained results highlight the importance of considering the interconnected impacts of these vibrations when designing and implementing robust control ***,integrating these compo-nents can increase the durability of drill bits and drill strings,as well as improve the ability to monitor and detect ***,by exploiting theseﬁndings,the assessment of structural resilience in rotary drilling systems can be ***,the study demonstrates the capacity of structural health monitoring to improve the quality,dependability,and efﬁciency of rotary drilling systems in the petroleum industry.

关键词： Rotary drilling systems mechanical vibrations structural durability dynamic interaction analysis ﬁeld data analysis

A low redox potential and long life organic anode material for sodium-ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 557-564页

作者： Zhi Li Yang Wei Kang Zhou Xin Huang Xing Zhou Jie Xu Taoyi kong Junwei Lucas Bao Xiaoli Dong Yonggang Wang Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Institute of New Energy Collaborative Innovation Center of Chemistry for Energy Materials (iChEM) Fudan University Department of Chemistry Boston College School of Materials Science and Engineering Anhui University of Technology

Sodium-ion batteries （SIBs） with organic electrodes are an emerging research direction due to the sustainability of organic materials based on elements like C,H,O,and sodium ***,organic electrode materials for SIBs are mainly used as cathodes because of their relatively high redox potentials（>1 V）.Organic electrodes with low redox potential that can be used as anode are ***,a novel organic anode material （tetrasodium 1,4,5,8-naphthalenetetracarboxylate,Na4TDC） has been developed with low redox potential （<0.7 V） and excellent cyclic *** three-sodium storage mechanism was demonstrated with various in-situ/ex-situ spectroscopy and theoretical calculations,showing a high capacity of 208 mAh/g and an average decay rate of merely 0.022%per ***,the Na4TDC-hard carbon composite can further acquire improved capacity and cycling stability for 1200 cycles even with a high mass loading of up to 20 mg *** pairing with a thick Na3V2（PO4）3cathode (20.6 mg cm-2),the as-fabricated full cell exhibited high operating voltage （2.8 V）,excellent rate performance and cycling stability with a high capacity retention of 88.7% after 200 cycles,well highlighting the Na4TDC anode material for SIBs.

关键词： Organic anode material Low redox potential Composite anode Sodium-ion batteries

A new perspective on polyethylene-promoted lignin pyrolysis with mass transfer and radical explanation

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Green Energy & Environment 2022年第6期7卷 1318-1326页

作者： Yuyang fan chao Liu Xiangchen kong Yue Han Ming Lei Rui Xiao Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing210096China

Co-pyrolysis of lignin and waste plastics,for example polyethylene(PE),has been studied,but related reports are basically on condition *** study revealed a new perspective on PE-promoted lignin pyrolysis to phenolic monomers with mass transfer and radical *** and PE were first pyrolyzed individually to identify pyrolysis characteristics,pyrolytic products,as well as the suitable copyrolysis ***,co-pyrolysis of blended lignin/PE with various ratios was *** of lignin products reached the maximum under lignin/PE ratio of 1:1,but blended approach always inhibited the production of lignin *** resulted from the poor mass transfer and interactions between lignin and PE,in which PE pyrolysates could easily escape from the particle *** in layered approach,PE pyrolysates had to pass through the lignin layer which contributed to the good interactions with lignin pyrolysis intermediates,thus the yields of lignin-derived products were significantly *** between lignin and PE(or their pyrolysates)were mainly radical quenching reactions,and X-ray photoelectron spectrum(XPS)and electron paramagnetic resonance(EPR)of pyrolytic chars were conducted to verify these interactions controlled by mass *** percentage of C]C(sp^(2))and concentration of organic stable radicals in layered lignin/PE char were both the lowest compared with those in blended lignin/PE and lignin char,indicating the stabilization of lignin-derived radicals by PE ***,the spin concentration of radicals in the char from layered char/PE was lower than that in lignin char,which further affirmed the quenching of radicals by PE in the layered co-pyrolysis mode.

关键词： Lignin Polyethylene Pyrolysis Radical Mechanism