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人口普查遗漏的组合式估计方法

统计与信息论坛 2024年第2期39卷 3-14页

作者：胡桂华 lOpez-carr david 黄艳华吴笛重庆工商大学数学与统计学院重庆400067 重庆工商大学成渝地区双城经济圈建设研究院重庆400067 加州大学圣芭芭拉分校地理系加利福尼亚圣芭芭拉93106

以人口普查标准时点上的人口总体(全国、全国以下各行政区)为研究对象,研究如何利用对总体登记的普查人口名单和覆盖调查人口名单构造的组合式遗漏估计量估计人口普查遗漏人口数。目前各国政府统计部门在人口普查遗漏估计中主要使用单... 详细信息

以人口普查标准时点上的人口总体(全国、全国以下各行政区)为研究对象,研究如何利用对总体登记的普查人口名单和覆盖调查人口名单构造的组合式遗漏估计量估计人口普查遗漏人口数。目前各国政府统计部门在人口普查遗漏估计中主要使用单重遗漏估计量,但该方法未包括同时遗漏于这两份调查人口名单的双重遗漏人口,低估了总体普查遗漏人口数。组合式遗漏估计量除了包括单重遗漏人口外,还包括了双重遗漏人口,避免了单重遗漏估计量的缺陷。采取抽样估计和数理模型相结合的方法研究单重遗漏估计量、双重遗漏估计量和组合式遗漏估计量,理论和数据分析结果表明:组合式遗漏估计量在抽样估计精度和遗漏人口数估计上优于单重遗漏估计量,尤其是在分析双重遗漏人口特征和改进未来人口普查登记工作等方面;在使用刀切法近似计算总体的组合式遗漏估计量的抽样方差时,不能忽视等概率人口层之间的协方差,否则可能低估或高估其抽样方差;单重遗漏估计量和组合式遗漏估计量属于有偏估计量,要使用均方误差比较其估计精度。本文创新之处在于,利用原始数据全面演示了单重遗漏估计量、双重遗漏估计量和组合式遗漏估计量及其抽样方差估计量等的详细计算过程,同时讨论了其统计性质,尤其是利用设置的数据模拟了有偏性,有助于中国人口普查遗漏估计方案的科学制定及估计精度的提高。

关键词：政府统计人口普查质量评估单重遗漏估计量双重遗漏估计量组合式遗漏估计量不完整二维列联表

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人口统计分析模型与人口普查净误差估计

系统科学与数学 2024年

作者：余鲁李婷 david lópez-carr 胡桂华吴笛漆莉重庆工商大学数学与统计学院 Department of Geography America University of California 重庆工商大学统计智能计算与监测重庆市重点实验室

本文旨在引入美国的人口统计分析模型,建立适合于在我国应用的人口统计分析模型.采取文献解读法和概率模型法,研究人口统计分析模型及其相关问题.研究结果表明:人口统计分析模型在我国的研究尚处于起步阶段,建立我国的人口统计分析模型... 详细信息

本文旨在引入美国的人口统计分析模型,建立适合于在我国应用的人口统计分析模型.采取文献解读法和概率模型法,研究人口统计分析模型及其相关问题.研究结果表明:人口统计分析模型在我国的研究尚处于起步阶段,建立我国的人口统计分析模型,不能照搬美国的人口统计分析模型,而应该结合我国实际情况有所改进与创新;建立人口统计分析模型分为两个层次,一是建立基于全面资料的人口统计分析模型,无需计算抽样方差,二是建立基于抽样调查资料的人口统计分析模型,需采用刀切法近似计算其抽样方差;人口统计分析模型的优势是,充分利用了出生、死亡及国际迁移等人口行政记录资料,节约了数据采集成本,与人口普查独立,劣势是,估计结果具有不确定性,尤其是其中的国际净迁移人数的估计结果差异较大.人口统计分析模型有望应用于我国2030年人口普查净误差估计,开创我国在该领域使用人口统计分析模型的先河.

关键词：人口普查人口普查质量评估行政记录抽样调查刀切法

Experimental implementation of phase triplicator gratings in a spatial light modulator

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Chinese Optics letters 2024年第2期22卷 64-69页

作者：高尚 María del Mar Sánchez-lópez Ignacio Moreno Instituto de Bioingeniería Universidad Miguel HernándezElche 03202Spain Departamento de Física Aplicada Universidad Miguel HernándezElche 03202Spain Departamento de Ciencia de Materiales Óptica y Tec.Electr´onicaUniversidad Miguel HernándezElche 03202Spain

In this work,we compare different methods for implementing a triplicator,a phase grating that generates three equiintense diffraction *** design with optimal efficiency features a continuous phase profile,which cannot be easily reproduced,and is typically affected by *** compare its performance with binary and sinusoidal phase *** also analyze the effect of quantizing the phase ***,a random approach is adopted to eliminate the additional harmonic *** all cases,a liquid-crystal-on-silicon spatial light modulator is employed to experimentally verify and compare the different approaches.

关键词： diffraction gratings phase modulation triplicator spatial light modulators

Metal-modulated epitaxy of Mg-doped Al_(0.80)In_(0.20)N-based layer for application as the electron blocking layer in deep ultraviolet light-emitting diodes

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Journal of Semiconductors 2024年第5期45卷 80-89页

作者： Horacio Irán Solís-Cisneros Carlos Alberto Hernández-Gutiérrez Enrique Campos-González Máximo lópez-lópez Optomechatronics Group Tecnológico Nacional de México Campus Tuxtla Gutiérrezcarretera Panamericana 1080C.P.29050Tuxtla GutiérrezChiapasMéxico Departamento de Física Instituto Nacional de Investigaciones NuclearesCarretera México-Toluca s/nC.P.52750La Marquesa OcoyoacacMéxico Departamento de Física Centro de Investigación y estudios Avanzados del Instituto Politécnico NacionalAv.Instituto Politécnico Nacional 2508San Pedro ZacatencoGustavo A.Madero07360 Ciudad de MéxicoCDMXMéxico

This work reports the growth and characterization of p-AlInN layers doped with Mg by plasma-assisted molecular beam epitaxy(PAMBE).AlInN was grown with an Al molar fraction of 0.80 by metal-modulated epitaxy(MME)with a thickness of 180 nm on Si(111)substrates using AlN as buffer *** substrate temperatures were used to enhance the incorporation of indium atoms into the alloy without clustering,as confirmed by X-ray diffraction(XRD).Cathodoluminescence measurements revealed ultraviolet(UV)range ***,Hall effect measurements indicated a maximum hole mobility of 146 cm^(2)/(V∙s),corresponding to a free hole concentration of 1.23×10^(19)cm^(−3).The samples were analyzed by X-ray photoelectron spectroscopy(XPS)estimating the alloy composition and extracting the Fermi level by valence band ***-doped AlInN layers were studied for use as the electron-blocking layer(EBl)in lED *** varied the Al composition in the EBl from 0.84 to 0.96 molar fraction to assess its theoretical effects on electroluminescence,carrier concentration,and electric field,using SIlVACO *** results from this study highlight the importance and capability of producing high-quality Mg-doped p-AlInN layers through *** simulations suggest that an Al content of 0.86 is optimal for achieving desired outcomes in electroluminescence,carrier concentration,and electric field.

关键词： metal-modulated epitaxy AlInN DUV-lED EBl simulation

Oligodendroctyes:the forgotten players of diabetes pathophysiology

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Neural Regeneration Research 2024年第11期19卷 2349-2350页

作者： Juan Antonio lópez-Villodres Beatriz García-Díaz Departamento Fisiología Humana Histología HumanaAnatomía Patológica y Educación Física y DeportivaFacultad de MedicinaUniversidad de MálagaMálagaSpain UGC Neurociencia.Instituto de Investigación Biomédica de Málaga y Plataforma en Nanomedicina(IBIMA Plataforma Bionand) MálagaSpain

Oligodendrocytes(Ols),glial cells that provide myelin sheaths to axons in the central nervous system(CNS),have a dual ***,this myelin fatty cover around the axons protects the nerves and is crucial for the saltatory propagation of action *** and not less important,Ols provide trophic support to neurons and ***,Ol metabolism is important for Ol well-being and the proper accomplishment of their functions,and Ol metabolism energetics directly affect the energy metabolism of neighboring neurons.

关键词： metabolism nerves myelin

Prevalence of Helicobacter pylori infection among patients with esophageal carcinoma

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World Journal of Gastroenterology 2024年第29期30卷 3479-3487页

作者： Miriam lópez-Gómez Maria Morales Rebeca Fuerte Marta Muñoz Pedro-david Delgado-lópez Jorge Francisco Gómez-Cerezo Enrique Casado Department of Medical Oncology Precision Oncology LaboratoryInfanta Sofía University HospitalSan Sebastián de los Reyes 28231MadridSpain Department of Medical Oncology Infanta Sofía University HospitalSan Sebastián de los Reyes 28702Spain Department of Internal Medicine Infanta Sofía University HospitalSan Sebastián de los Reyes 28703MadridSpain Department of Pathology Infanta Sofía University HospitalSan Sebastián de los Reyes 28702Spain Department of Neurosurgery Burgos University HospitalBurgos 09006Spain Department of Internal Medicine Infanta Sofía University Hospital and Henares University Hospital Foundation for Biomedical Research and InnovationSan Sebastian de los Reyes 28702MadridSpain Department of Medical Oncology Infanta Sofia University Hospital and Henares University Hospital Foundation for Biomedical Research and InnovationSan Sebastian de los Reyes 28702MadridSpain

BACKGROUND Helicobacter pylori(***)is a widespread microorganism related to gastric adenocarcinoma(AC).In contrast,it has been reported that an inverse association exists between *** infection and esophageal *** mechanisms underlying this supposedly protective effect remain *** To determine the prevalence of *** infection in esophageal carcinoma patients,we performed a retrospective observational study of esophageal tumors diagnosed in our *** We retrospectively reviewed the prevalence of *** infection in a cohort of patients diagnosed with esophageal *** or previous proton pump inhibitor(PPI)usage was also *** A total of 89 patients with esophageal carcinoma(69 males,77.5%),with a mean age of 66 years(range,26-93 years)were *** was the most frequent pathological variant(n=47,52.8%),followed by squamous cell carcinoma(n=37,41.6%).Fourteen ACs(29.8%)originated in the gastroesophageal junction and 33(70.2%)in the esophageal ***,54 patients(60.7%)presented at stages III and *** *** infection occurred only in 4 patients(4.5%),3 with AC(6.3%of all ACs)and 1 with squamous cell carcinoma(2.7%of all squamous cell tumors).All patients with previous *** infection had stage *** one patient had received prior *** eradication therapy,whereas 86(96.6%)had received previous or concomitant PPI *** In our cohort of patients,and after histologic evaluation of paraffin-embedded primary tumors,we found a very low prevalence of previous *** *** also reviewed the medical history of the patients,concluding that the majority had received or were on PPI *** minimal prevalence of *** infection found in this cohort of patients with esophageal carcinoma suggests a protective role.

关键词： Helicobacter pylori Eradication Esophageal tumor Dysbiosis Proton pump inhibitors Carcinogenesis Microbiota Incidence

Experimental and numerical investigation to elucidate the fluid flow through packed beds with structured particle packings

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Particuology 2024年第6期89卷 218-237页

作者： Shirin Patil Christian Gorges Joel lòpez Bonilla Moritz Stelter Frank Beyrau Berend van Wachem laboratory of Technical Thermodynamics Otto-von-Guericke-Universität MagdeburgUniversitätsplatz 239106 MagdeburgGermany Chair of Mechanical Process Engineering Otto-von-Guericke-Universität MagdeburgUniversitätsplatz 239106 MagdeburgGermany

The present paper presents an experimental and numerical investigation of the dispersion of the gaseous jet flow and co-flow for the simple unit cell(SUC)and body-centred cubic(BCC)configuration of particles in packed *** experimental setup is built in such a way that suitable and simplified boundary conditions are imposed for the corresponding numerical framework,so the simulations can be done under very similar conditions as the ***,a porous plate is used for the co-flow to achieve the uniform velocity and the fully developed flow is ensured for the jet *** SUC and BCC particle beds consist of 3D-printed spheres,and the non-isotropy near the walls is mostly eliminated by placing half-spheres at the channel *** flow velocities are analysed directly at the exit of the particle bed for both beds over 36 pores for the SUC configuration and 60 pores for the BCC configuration,for particle Reynolds numbers of 200,300,and *** particle image velocimetry is experimentally arranged in such a way that the velocities over the entire region at the exit of the packed bed are obtained *** numerical method consists of a state-of-the-art immersed boundary method with adaptive mesh *** paper presents the pore jet structure and velocity field exiting from each pore for the SUC and BCC packed particle *** numerical and experimental studies show a good agreement for the SUC configuration for all flow *** the BCC configuration,some differences can be observed in the pore jet flow structure between the simulations and the experiments,but the general flow velocity distribution shows a good overall *** axial velocity is generally higher for the pores located near the centre of the packed bed than for the pores near the *** addition,the axial velocities are observed to increase near the peripheral pores of the packed *** behaviour is predominant for the BCC configuration as compared to t

关键词： Uniform particle packing Packed bed reactor Stereo particle image velocimetry Immersed boundary method

Digital Social Connectedness as a lifeline for Older People: Use and Non-use of VinclesBCN During the Pandemic

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International Journal of Disaster Risk Science 2024年第2期15卷 251-264页

作者： Israel Rodríguez‑Giralt Daniel lópez‑Gómez Roser Beneito‑Montagut CareNet IN3Universitat Oberta de Catalunya08018 BarcelonaSpain School of Social Sciences Cardif UniversityCardif CF103NSWalesUK

This article presents the results of a study that evaluated VinclesBCN during COVID-19. This digital-based public social service aims to prevent loneliness and isolation in +65-year-old adults living in Barcelona. Through service user(N = 12) and professional(N = 6) interviews and a questionnaire with service users(N = 255), we demonstrate the pivotal role of digital connectedness in transforming VinclesBCN into a lifeline during the pandemic. The analysis revealed the importance of sociability, social support, and, especially, entertainment in coping with pandemic fatigue and facilitating social connectivity and support among users. Users engaged in activities such as sharing images, songs, memes, and daily greetings to provide proximity, sociability, and care among users, whether they belonged to preexisting groups or were newly introduced to the platform. It also facilitated the identification of individuals who needed companionship, comfort, or more specialized support. The findings emphasize the significance of entertainment as a resilience-building strategy during times of uncertainty. Despite the positive impact, not all users equally used the platform. Non-use was strongly associated with being a woman, having a low educational level, having preexisting social relationships, less time of enrolment in the platform, as well as a high perception of loneliness, poor self-reported health, and low mood. The article underscores the need for further research into older adults' digital engagement during crises, its role in building resilience, and advocating for inclusive digital interventions that take into account diverse older adults' needs and experiences in crisis contexts.

关键词： Barcelona COVID-19 pandemic Digital social connectedness Entertainment Older adult resilience Public digital service

Electrifying Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ) for focalized heating in oxygen transport membranes

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Journal of Energy Chemistry 2024年第4期91卷 99-110页

作者： Marwan laqdiem Julio García-Fayos laura Almar Alfonso J.carrillo Álvaro Represa JoséM.lópez Nieto Sonia Escolástico david Catalán-Martinez Jose M.Serra Instituto de Tecnología Química(Universitat Politècnica de València–Consejo Superior de Investigaciones Científicas) Av.Los Naranjos s/nE-46022 ValenciaSpain

Industry decarbonization requires the development of highly efficient and flexible technologies relying on renewable energy resources,especially biomass and solar/wind *** the case of pure oxygen production,oxygen transport membranes(OTMs)appear as an alternative technology for the cryogenic distillation of air,the industrially-established process of producing ***,OTMs could provide oxygen from different sources(air,water,CO_(2),etc.),and they are more flexible in adapting to current processes,producing oxygen at 700^(-1)000℃.Furthermore,OTMs can be integrated into catalytic membrane reactors,providing new pathways for different *** first part of this study was focused on electrification on a traditional OTM material(Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ)),imposing different electric currents/voltages along a capillary *** to the emerging Joule effect,the membrane-surface temperature and the associated O_(2) permeation flux could be ***,the OTM is electrically and locally heated and reaches 900℃on the surface,whereas the surrounding of the membrane was maintained at 650℃.The O_(2)permeation flux reached for the electrified membranes was~3.7 Nml min^(-1)cm^(-2),corresponding to the flux obtained with an OTM non-electrified at 900℃.The influence of depositing a porous Ce_(0.8)Tb_(0.2)O_(2-δ) catalytic/protective layer on the outer membrane surface revealed that lower surface temperatures(830℃)were detected at the same imposed electric ***,the electrification concept was demonstrated in a catalytic membrane reactor(CMR)where the oxidative dehydrogenation of ethane(ODHE)was carried *** reaction is very sensitive to temperature,and here,we demonstrate an improvement of the ethylene yield by reaching moderate temperatures in the reaction chamber while the O_(2) injection into the reaction can be easily fine-tuned.

关键词： Oxygen permeation Oxidative dehydrogenation of ethane Oxygen transport membranes Joule effect Mixed ionic-electronic conductors Catalytic membrane reactors