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A Note on Generalized Inverses of Distribution Function and Quantile Transform.tion

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Applied m.them.tics 2012年第12期3卷 2098-2100页

作者： Changyong Feng Hongyue Wang xin m. tu Jeanne Kowalski Departm.nt of Biostatistics & Bioinform.tics Rollins School of Public Health Winship Cancer Institute Atlanta USA Departm.nt of Biostatistics and Com.utational Biology University of Rochester Rochester USA

In this paper we study the relations of four possible generalized inverses of a general distribution functions and their right-continuity properties. We correct a right-continuity result of the generalized inverse used in statistical literature. We also prove the validity of a new generalized inverse which is always right-continuous.

关键词： Distribution Function Quantile Function Right Continuity

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单因素与多因素逻辑回归的不一致性（英文）

上海精神医学 2017年第2期29卷 124-128页

作者： Hongyue WANG Jing PENG Bokai WANG Xiang LU Julia Z.ZHENG Kejia WANG xin m.tu Changyong FENG Departm.nt of Biostatistics and Com.utational Biology University of Rochester Rochester NY USA Departm.nt of Anesthesiology University of Rochester Rochester NY USA Departm.nt of m.crobiology and Im.unology McGill University Montreal QC Canada Departm.nt of Fam.ly m.dicine and Public Health University of California San Diego La Jolla CA USA

逻辑回归是研究协变量对二元结果影响的一种常用的统计方法。它已被广泛应用于临床试验和观察性研究。然而,单因素回归得到的结果和多元逻辑回归得到的结果往往是相互矛盾的。在多元回归中可能对结果会显示出非常强烈的影响的一个协变... 详细信息

逻辑回归是研究协变量对二元结果影响的一种常用的统计方法。它已被广泛应用于临床试验和观察性研究。然而,单因素回归得到的结果和多元逻辑回归得到的结果往往是相互矛盾的。在多元回归中可能对结果会显示出非常强烈的影响的一个协变量在单因素回归中可能不会,反之亦然。这些事实在生物医学研究中并没有引起足够的重视。误用逻辑回归在医学出版物中非常普遍。在本文中,我们研究了单因素和多因素逻辑回归分析的不一致性,并在多元逻辑回归分析的模型部分中给出建议。

关键词：条件期望模型选择逻辑回归

Fine-grained grid com.uting m.del for Wi-Fi indoor localization in com.lex environm.nts

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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 Com.uter Engineering Chengdu Technological UniversityChengdu611730China HAN Networks Corporation Lim.ted Beijing100094China

The fingerprinting-based approach using the wireless local area network(WLAN)is widely used for indoor localization.However,the construction of the fingerprint database is quite tim.-consum.ng.Especially when the position of the access point(AP)or wall changes,updating the fingerprint database in real-tim. is difficult.An appropriate indoor localization approach,which has a low im.lem.ntation cost,excellent real-tim. perform.nce,and high localization accuracy and fully considers com.lex indoor environm.nt factors,is preferred in location-based services(LBSs)applications.In this paper,we proposed a fine-grained grid com.uting(FGGC)m.del to achieve decim.ter-level localization accuracy.Reference points(RPs)are generated in the grid by the FGGC m.del.Then,the received signal strength(RSS)values at each RP are calculated with the attenuation factors,such as the frequency band,three-dim.nsional propagation distance,and walls in com.lex environm.nts.As a result,the fingerprint database can be established autom.tically without m.nual m.asurem.nt,and the efficiency and cost that the FGGC m.del takes for the fingerprint database are superior to previous m.thods.The proposed indoor localization approach,which estim.tes the position step by step from.the approxim.te grid location to the fine-grained location,can achieve higher real-tim. perform.nce and localization accuracy sim.ltaneously.The m.an error of the proposed m.del is 0.36 m.far lower than that of previous approaches.Thus,the proposed m.del is feasible to im.rove the efficiency and accuracy of Wi-Fi indoor localization.It also shows high-accuracy perform.nce with a fast running speed even under a large-size grid.The results indicate that the proposed m.thod can also be suitable for precise m.rketing,indoor navigation,and em.rgency rescue.

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

Experim.ntal study on effects of gas flow rate on soot characteristics in diffusion flam.s coupled with plasm.

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

作者： QI DanDan CHEN m.ngXiao tu xin LIU Dong m.IT Key Laboratory of Therm.l Control of Electronic Equipm.nt School of Energy and Power EngineeringNanjing University of Science and TechnologyNanjing 210094China Advanced Com.ustion Laboratory School of Energy and Power EngineeringNanjing University of Science and TechnologyNanjing 210094China Departm.nt of Electrical Engineering and Electronics University of LiverpoolLiverpool L693GJUK

This study exam.ned the evolution of m.rphology and nanostructure of soot particles from.the plasm.-flam. interaction for various gas flow rates.The current study used both optical diagnostic and sam.ling m.thods to explore the soot production and com.ustion characteristics.Soot particles were characterized at the sam. positions downstream.from.the flam. zone by therm.phoretic sam.ling and transm.ssion electron m.croscopy.m.reover,X-ray diffraction analysis,and therm.gravim.tric analysis were perform.d to study the nanostructure and oxidation reactivity of soot.A reduction in soot concentration was found with the plasm. addition,which illustrated an inhibition effect of plasm. on soot em.ssion.The increased gas flow rate prom.ted soot concentration since a growing num.er of carbons participated in the com.ustion process.Depending on the gas flow rate(carbon content)variation and plasm. activation,either liquid-like soot m.terial with irregularly shaped protrusions or chain-like structure,or a m.xture of both,were generated from.the diffusion flam.s.The soot produced by plasm.-flam. interaction also dem.nstrated a high correlation between nanostructure and reactivity.The soot from.lower carbon content with plasm. activation had a shorter fringe length and larger fringe tortuosity related to higher oxidation reactivity.On the contrary,soot from.the highest carbon content without plasm.-flam. interaction exhibited prevalent fullerene-like nanostructures with evident large or sm.ll shells and also had a higher carbonization degree resulting in lower oxidation reactivity.

关键词： soot characteristics gas flow rate plasm. diffusion flam.s

Assessm.nt of the Characteristics of Dem.rsal Fish Com.unities 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 m.riculture(Ocean University of China) Ministry of EducationQingdao 266003China Shandong Fisheries Developm.nt and Resource Conservation Center Yantai 264003China

Biodiversity declines have m.tivated m.ny studies on the relationship between species diversity and ecosystem.functioning.In this study,we described the spatial-tem.oral characteristics of dem.rsal fish com.unities along a coastal habitat in Rongcheng Bay,Shandong Peninsula,China with both species-based and biological trait-based approaches.The field survey was carried out m.nthly using traps from.April to October of 2018,and divided into three seasons(spring:April and m.y;sum.er:June,July and August;autum.:Septem.er,October and Novem.er).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 sand.We analyzed the fish com.unities with three taxonom.c diversity indices,including Shannon-Wiener,Sim.son,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 traits.The results showed that there were no significant differences in taxonom.c diversity indices am.ng different habitats in the three seasons.However,significant differences were found in the functional richness of fish com.unities am.ng different habitats in three seasons.Seagrass bed represented the highest functional richness in spring and autum..This study dem.nstrates that seagrass bed is very im.ortant in enhancing the functional diversity of fish com.unities in a com.lex habitat.The study also indicates that the com.ination of taxonom.c diversity and functional diversity will provide a m.re detailed description of the characteristics of fish com.unities.

关键词： com.lex habitat biological traits biodiversity fish com.unities

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On testing proportional odds assum.tions for proportional odds m.dels

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General Psychiatry 2023年第3期36卷 214-219页

作者： Anqi Liu Hua He xin m.tu Wan Tang Departm.nt of Bostaistis and Data Science Tulane UniversityNew OrleansLouisianaUSA Departm.nt of Epidem.ology Tulane UniversityNew OrleansLouisianaUSA Division of Biostatistics and Bioinform.tics Herbert Wertheim School of Public Health and Human Longevity ScienceUC San DiegoLa JollaCaliforniaUSA

Proportional odds m.dels are com.only used to m.del ordinal responses,but the proportional odds assum.tion m.y not hold in practice,leading to biased inference.Tests such as score,Wald and likelihood ratio(LR)have been proposed to evaluate the proportional odds assum.tion based on m.dels without the assum.tion.Brant has proposed an independent binary m.del-based Wald-type test,and Wolfe and Gould have extended the idea to propose an LR-type test.This paper provides a brief review of the Brant and Wolfe-Gould tests for evaluating the proportional odds assum.tion and evaluates their perform.nce through sim.lation studies and a real data exam.le.Sam.le program. are provided in SAS,SPSS and Stata to facilitate the im.lem.ntation of these tests using standard statistical software packages.This study highlights the im.ortance of evaluating the proportional odds assum.tion when using proportional odds m.dels for ordinal responses.The sam.le program. provided in this paper m.ke it easy for researchers to apply these tests in their own analyses using standard statistical software packages.

关键词： Gould testing apply

On m.delling relative risks for longitudinal binom.al responses:im.lications from.two dueling paradigm.

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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 Bioinform.tics Herbert Wertheim School of Public Health and Human Longevity ScienceUC San DiegoLa JollaCaliforniaUSA College of Environm.ntal Science and Engineering Tongji UniversityShanghaiChina Departm.nt of m.them.tics and Statistics Georgia State UniversityAtlantaGeorgiaUSA Division of Biostatistics Department of Preventive MedicineNorthwestern University Feinberg School of MedicineChicagoIllinoisUSA

Although logistic regression is the m.st popular for m.delling regression relationships with binary responses,m.ny find relative risk(RR),or risk ratio,easier to interpret and prefer to use this m.asure of risk in regression analysis.Indeed,since Zou published his m.dified Poisson regression approach for m.delling RR for cross-sectional data,his paper has been cited over 7000 tim.s,dem.nstrating the popularity of this alternative m.asure of risk in regression analysis involving binary responses.As longitudinal studies have becom. increasingly popular in clinical trials and observational studies,it is im.erative to extend Zou’s approach for longitudinal data.The two m.st popular approaches for longitudinal data analysis are the generalised linear m.xed-effects m.del(GLm.)and generalised estim.ting equations(GEE).However,the param.tric GLm. 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 response.On the other hand,as it im.oses no m.them.tical m.del on data distributions,the sem.param.tric GEE is coherent with Zou’s m.dified Poisson regression.In this paper,we develop a GEE-based longitudinal m.del for binary responses to provide inference about RR.

关键词： sectional coherent estim.ting

Clinical review and literature analysis of hepatic epithelioid angiom.olipom. in alcoholic cirrhosis: A case report

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World Journal of Clinical Cases 2024年第14期12卷 2382-2388页

作者： Jing-Qiang Guo Jia-Hui Zhou Kun Zhang xin-Liang Lv Chao-Yong tu Departm.nt of Hepatobiliary and Pancreatic Surgery Lishui Municipal Central HospitalLishui 323000Zhejiang ProvinceChina Departm.nt of Pathology Lishui Municipal Central HospitalLishui 323000Zhejiang ProvinceChina Departm.nt of General Surgery The Fifth Affiliated Hospital of Wenzhou Medical UniversityLishui 323000Zhejiang ProvinceChina

BACKGROUND Hepatic epithelioid angiom.olipom.(HEA)has a low incidence and both clinical m.nifestations and im.ging lack specificity.Thus,it is easy to m.sdiagnose HEA as other tum.rs of the liver,especially in the presence of liver diseases such as hepatitis cirrhosis.This article reviewed the diagnosis and treatm.nt of a patient with HEA and alcoholic cirrhosis,and analyzed the literature,in order to im.rove the understanding of this disease.CASE SUm.ARY A 67-year-old m.le patient with a history of alcoholic cirrhosis was adm.tted due to the discovery of a space-occupying lesion in the liver.Based on the patient’s history,laboratory exam.nations,and im.ging exam.nations,a m.lignant liver tum.r was considered and laparoscopic partial hepatectom. was perform.d.Postoperative pathology showed HEA.During outpatient follow-up,the patient showed no sign of recurrence.CONCLUSION HEA is difficult to m.ke a definite diagnosis before surgery.HEA has the poten-tial for m.lignant degeneration.If conditions perm.t,surgical treatm.nt is recom.m.nded.

关键词： Hepatic epithelioid angiom.olipom. Alcoholic cirrhosis m.gnetic resonance im.ging Com.uted tom.graphy Im.unohistochem.stry m.sdiagnose analysis Case report

Ultrathin GaN Film.Derived from.Am.rphous Ga_(2)O_(3) Film

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Journal of Wuhan University of Technology(m.terials 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 m.terials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China State Key Laboratory of Silicate m.terials for Architectures School of Materials Science and EngineeringWuhan University of TechnologyWuhan 430070China

It rem.ins a big challenge to synthesize two-dim.nsional(2D)GaN m.terial for applications in power nanodevices.Traditional synthetic m.thods require com.lex equipm.nt and processes and tim. consum.ng.Here,we reported a two-step route to prepare polycrystalline 2D GaN film.The am.rphous ultrathin Ga_(2)O_(3)film.was first exfoliated from.the surface of liquid gallium.In a vapor phase reaction,2D Ga_(2)O_(3)film.was then converted into 2D GaN film.while m.intaining the 2D m.rphology.Ram.n and high-resolution transm.ssion electron m.croscope(HRTEm.analysis im.lies the successful synthesis of wurtzite-type GaN ultrathin film.This sim.le strategy proposed in this work will provide m.re opportunities for applications of GaN ultrathin film.in m.ny devices.

关键词： GaN Ga_(2)O_(3) liquid gallium