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On modelling relative risks for longitudinal binomial responses:implications from two dueling paradigms

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General Psychiatry 2023年第2期36卷 143-147页

作者： tuo Lin Rongzhe Zhao Shengjia tu Hao Wu Hui Zhang xin m tu Division of Biostatistics and Bioinformatics Herbert Wertheim School of Public Health and Human Longevity ScienceUC San DiegoLa JollaCaliforniaUSA College of Environmental Science and Engineering Tongji UniversityShanghaiChina Department of mathematics and Statistics Georgia State UniversityAtlantaGeorgiaUSA Division of Biostatistics Department of Preventive MedicineNorthwestern University Feinberg School of MedicineChicagoIllinoisUSA

Although logistic regression is the most popular for modelling regression relationships with binary responses,many find relative risk(RR),or risk ratio,easier to interpret and prefer to use this measure of risk in regression ***,since Zou published his modified Poisson regression approach for modelling RR for cross-sectional data,his paper has been cited over 7000 times,demonstrating the popularity of this alternative measure of risk in regression analysis involving binary *** longitudinal studies have become increasingly popular in clinical trials and observational studies,it is imperative to extend Zou’s approach for longitudinal *** two most popular approaches for longitudinal data analysis are the generalised linear mixed-effects model(GLmm)and generalised estimating equations(GEE).However,the parametric GLmm cannot be used for the extension within the current context,because Zou’s approach treats the binary response as a Poisson variable,which is at odds with the Bernoulli distribution for the binary *** the other hand,as it imposes no mathematical model on data distributions,the semiparametric GEE is coherent with Zou’s modified Poisson *** this paper,we develop a GEE-based longitudinal model for binary responses to provide inference about RR.

关键词： sectional coherent estimating

Inconsistency between overall and subgroup analyses

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General Psychiatry 2022年第3期35卷 201-204页

作者： Hongyue Wang Bokai Wang xin m tu Changyong Feng Departments of Biostatistics&Computational Biology University of RochesterRochesterNew YorkUSA Division of Biostatistics and Bioinformatics Herbert Wertheim School of Public Health and Human Longevity ScienceUC San DiegoLa JollaCaliforniaUSA

Suppose we have a sample of subjects in two treatment *** study the difference of the treatment effects,we can analyse the data using all subjects(overall analysis).We may also divide the subjects into several subgroups based on some covariates of interest(eg,gender),and study the treatment effects within each *** results of these two analyses may be different or even in opposite *** this paper,we give a general sufficient condition of consistency between the overall and subgroup analyses.

关键词： subgroup consistency groups.

Fine-grained grid computing model for Wi-Fi indoor localization in complex environments

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Journal of Electronic Science and Technology 2024年第1期22卷 42-52页

作者： Yan Liang Song Chen xin Dong tu Liu School of Computer Engineering Chengdu Technological UniversityChengdu611730China HAN Networks Corporation Limited Beijing100094China

The fingerprinting-based approach using the wireless local area network(WLAN)is widely used for indoor ***,the construction of the fingerprint database is quite *** when the position of the access point(AP)or wall changes,updating the fingerprint database in real-time is *** appropriate indoor localization approach,which has a low implementation cost,excellent real-time performance,and high localization accuracy and fully considers complex indoor environment factors,is preferred in location-based services(LBSs)*** this paper,we proposed a fine-grained grid computing(FGGC)model to achieve decimeter-level localization *** points(RPs)are generated in the grid by the FGGC ***,the received signal strength(RSS)values at each RP are calculated with the attenuation factors,such as the frequency band,three-dimensional propagation distance,and walls in complex *** a result,the fingerprint database can be established automatically without manual measurement,and the efficiency and cost that the FGGC model takes for the fingerprint database are superior to previous *** proposed indoor localization approach,which estimates the position step by step from the approximate grid location to the fine-grained location,can achieve higher real-time performance and localization accuracy *** mean error of the proposed model is 0.36 m,far lower than that of previous ***,the proposed model is feasible to improve the efficiency and accuracy of Wi-Fi indoor *** also shows high-accuracy performance with a fast running speed even under a large-size *** results indicate that the proposed method can also be suitable for precise marketing,indoor navigation,and emergency rescue.

关键词： Fine-grained grid computing (FGGC) Indoor localization Path loss Random forest Reference points(RPs)

Partial least squares regression and principal component analysis:similarity and differences between two popular variable reduction approaches

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General Psychiatry 2022年第1期35卷 67-71页

作者： Chenyu Liu xinlian Zhang Tanya T Nguyen Jinyuan Liu Tsungchin Wu Ellen Lee xin m tu Division of Biostatistics and Bioinformatics Herbert Wertheim School of Public Health and Human Longevity ScienceUC San DiegoLa JollaCaliforniaUSA Department of Psychiatry Stein Institute for Research on AgingUC San DiegoLa JollaCaliforniaUSA

SUmmARY In many statistical applications,composite variables are constructed to reduce the number of variables and improve the performances of statistical analyses of these variables,especially when some of the variables are highly *** component analysis(PCA)and factor analysis(FA)are generally used for such *** the variables are used as explanatory or independent variables in linear regression analysis,partial least squares(PLS)regression is a better *** PCA and FA,PLS creates composite variables by also taking into account the response,or dependent variable,so that they have higher correlations with the response than composites from their PCA and FA *** this report,we provide an introduction to this useful approach and illustrate it with data from a real study.

关键词： composite composites component

Experimental study on effects of gas flow rate on soot characteristics in diffusion flames coupled with plasma

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Science China(Technological Sciences) 2024年第2期67卷 475-485页

作者： QI DanDan CHEN mingXiao tu xin LIU Dong mIIT Key Laboratory of Thermal Control of Electronic Equipment School of Energy and Power EngineeringNanjing University of Science and TechnologyNanjing 210094China Advanced Combustion Laboratory School of Energy and Power EngineeringNanjing University of Science and TechnologyNanjing 210094China Department of Electrical Engineering and Electronics University of LiverpoolLiverpool L693GJUK

This study examined the evolution of morphology and nanostructure of soot particles from the plasma-flame interaction for various gas flow *** current study used both optical diagnostic and sampling methods to explore the soot production and combustion *** particles were characterized at the same positions downstream from the flame zone by thermophoretic sampling and transmission electron ***,X-ray diffraction analysis,and thermogravimetric analysis were performed to study the nanostructure and oxidation reactivity of soot.A reduction in soot concentration was found with the plasma addition,which illustrated an inhibition effect of plasma on soot *** increased gas flow rate promoted soot concentration since a growing number of carbons participated in the combustion *** on the gas flow rate(carbon content)variation and plasma activation,either liquid-like soot material with irregularly shaped protrusions or chain-like structure,or a mixture of both,were generated from the diffusion *** soot produced by plasma-flame interaction also demonstrated a high correlation between nanostructure and *** soot from lower carbon content with plasma activation had a shorter fringe length and larger fringe tortuosity related to higher oxidation *** the contrary,soot from the highest carbon content without plasma-flame interaction exhibited prevalent fullerene-like nanostructures with evident large or small shells and also had a higher carbonization degree resulting in lower oxidation reactivity.

关键词： soot characteristics gas flow rate plasma diffusion flames

machine learning-driven optimization of plasma-catalytic dry reforming of methane

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Journal of Energy Chemistry 2024年第9期96卷 153-163页

作者： Yuxiang Cai Danhua mei Yanzhen Chen Annemie Bogaerts xin tu Department of Electrical Engineering and Electronics University of LiverpoolLiverpool L693GJUK Research Group PLASmANT Department of ChemistryUniversity of AntwerpUniversiteitsplein 1BE-2610 Wilrijk-AntwerpBelgium College of Electrical Engineering and Control Science Nanjing Tech UniversityNanjing 211816JiangsuChina

This study investigates the dry reformation of methane(DRm)over Ni/Al_(2)O_(3)catalysts in a dielectric barrier discharge(DBD)non-thermal plasma reactor.A novel hybrid machine learning(mL)model is developed to optimize the plasma-catalytic DRm reaction with limited experimental *** address the non-linear and complex nature of the plasma-catalytic DRm process,the hybrid mL model integrates three well-established algorithms:regression trees,support vector regression,and artificial neural networks.A genetic algorithm(GA)is then used to optimize the hyperparameters of each algorithm within the hybrid mL *** mL model achieved excellent agreement with the experimental data,demonstrating its efficacy in accurately predicting and optimizing the DRm *** model was subsequently used to investigate the impact of various operating parameters on the plasma-catalytic DRm *** found that the optimal discharge power(20 W),CO_(2)/CH_(4)molar ratio(1.5),and Ni loading(7.8 wt%)resulted in the maximum energy yield at a total flow rate of∼51 mL/***,we investigated the relative significance of each operating parameter on the performance of the plasma-catalytic DRm *** results show that the total flow rate had the greatest influence on the conversion,with a significance exceeding 35%for each output,while the Ni loading had the least impact on the overall reaction *** hybrid model demonstrates a remarkable ability to extract valuable insights from limited datasets,enabling the development and optimization of more efficient and selective plasma-catalytic chemical processes.

关键词： Plasma catalysis machine learning Process optimization Dry reforming of methane Syngas production

Assessment of the Characteristics of Demersal Fish Communities Using Species-and Trait-Based Approaches in the Coastal Habitats Along Rongcheng Bay,Shandong Peninsula,China

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Journal of Ocean University of China 2024年第3期23卷 786-796页

作者： YUAN Shunjie SUN xin tu Zhong SUN Jie WANG Xianning ZHANG Peidong Key Laboratory of mariculture(Ocean University of China) Ministry of EducationQingdao 266003China Shandong Fisheries Development and Resource Conservation Center Yantai 264003China

Biodiversity declines have motivated many studies on the relationship between species diversity and ecosystem *** this study,we described the spatial-temporal characteristics of demersal fish communities along a coastal habitat in Rongcheng Bay,Shandong Peninsula,China with both species-based and biological trait-based *** field survey was carried out monthly using traps from April to October of 2018,and divided into three seasons(spring:April and may;summer:June,July and August;autumn:September,October and November).The study area included five distinct habitats:seagrass bed,natural rocky reef,bare sand,artificial reef together with natural rocky reef,and artificial reef together with bare *** analyzed the fish communities with three taxonomic diversity indices,including Shannon-Wiener,Simpson,and Pielou Evenness,as well as four functional diversity indices,including FRic,FEve,FDiv,and FDis,based on 7 functional groups which are categorized into 27 *** results showed that there were no significant differences in taxonomic diversity indices among different habitats in the three ***,significant differences were found in the functional richness of fish communities among different habitats in three *** bed represented the highest functional richness in spring and *** study demonstrates that seagrass bed is very important in enhancing the functional diversity of fish communities in a complex *** study also indicates that the combination of taxonomic diversity and functional diversity will provide a more detailed description of the characteristics of fish communities.

关键词： complex habitat biological traits biodiversity fish communities

Ultrathin GaN Film Derived from Amorphous Ga_(2)O_(3) Film

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Journal of Wuhan University of Technology(materials Science) 2024年第4期39卷 814-818页

作者：王鹏 ZHANG Binbin LIU Xiaofei ZHANG xin tu Rong ZHANG Song 李宝文 State Key Laboratory of Advanced Technology for materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China State Key Laboratory of Silicate materials for Architectures School of Materials Science and EngineeringWuhan University of TechnologyWuhan 430070China

It remains a big challenge to synthesize two-dimensional(2D)GaN material for applications in power *** synthetic methods require complex equipment and processes and time ***,we reported a two-step route to prepare polycrystalline 2D GaN *** amorphous ultrathin Ga_(2)O_(3)film was first exfoliated from the surface of liquid *** a vapor phase reaction,2D Ga_(2)O_(3)film was then converted into 2D GaN film while maintaining the 2D *** and high-resolution transmission electron microscope(HRTEm)analysis implies the successful synthesis of wurtzite-type GaN ultrathin *** simple strategy proposed in this work will provide more opportunities for applications of GaN ultrathin film in many devices.

关键词： GaN Ga_(2)O_(3) liquid gallium

An Assembly of Pyrano[3,2-b]indol-2-ones via NHC-Catalyzed[3+3]Annulation of Indolin-3-ones with Ynals

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Chinese Journal of Chemistry 2024年第13期42卷 1487-1492页

作者： Xia Wang Shulei Zhang Shao-Jie Wang Hao An Xiaolan xin Haonan Lin Zhifeng tu Shenci Lu Frontiers Science Center for Flexible Electronics(FSCFE) Shaanxi Institute of Flexible Electronics(SIFE)&Shaanxi Instituteof Biomedical Materials and Engineering(SiBME)Northwestern Polytechnical University(NPU)127 West Youyi RoadXi'anShaanxi 710072China School of Chemistry and Chemical Engineering Northwestern Polytechnical University(NPU)127 West Youyi RoadXi'anShaanxi 710072China

We report herein an unprecedented N-heterocyclic carbene-catalyzed formal[3+3]annulation of ynals with N-Ts indolin-3-ones under the oxidation condition affording the functionalized pyrano[3,2-b]*** alkynyl acylazoliums via the combination of a carbene with ynals in the presence of oxidate proved to be the important intermediates for the success of this *** method features a broad substrate scope and mild conditions,including axially chiral skeletons with suitable substitutions.

关键词： N-Heterocyclic carbene Annulation Organocatalysis Atropisomerism Carbazole Aldehydes Heterocycles Asymmetric catalysis