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肺结核发病的时空分布特征和气象因素分析

山东理工大学学报（自然科学版） 2025年第1期39卷 41-45页

作者：谢小义汉江师范学院数学与计算机科学学院湖北十堰442000

通过对2015—2019年全国肺结核发病率数据(不含香港地区、澳门地区和台湾地区)可视化,探究全国肺结核发病的时空分布特征;通过空间自相关分析和拉格朗日乘数(LM)检验,选取面板数据空间杜宾模型探究有关气象因素对肺结核发病的影响。研... 详细信息

通过对2015—2019年全国肺结核发病率数据(不含香港地区、澳门地区和台湾地区)可视化,探究全国肺结核发病的时空分布特征;通过空间自相关分析和拉格朗日乘数(LM)检验,选取面板数据空间杜宾模型探究有关气象因素对肺结核发病的影响。研究结果表明,每年的1月和3月是全国肺结核的高发期,且全国肺结核发病率存在空间聚集性,高发区域是新疆、西藏和青海等西北部地区;气温和湿度与当地肺结核发病是负相关关系,与周边地区的肺结核发病是正相关关系。

关键词：肺结核时间流行趋势空间分布特征空间杜宾模型

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开发区升格政策能促进企业创新增量提质吗?

太原学院学报（社会科学版） 2025年第1期26卷 92-106页

作者：张帅王筱依太原学院财经系山西太原030032

通过构建多时点DID模型实证检验开发区升格政策对企业创新数量和创新质量的影响,结果表明:省级开发区升格通过降低制度性交易成本、提升市场化程度和加速创新要素流入对企业创新产出数量和产出质量产生促进作用,该政策对非民营企业、非... 详细信息

通过构建多时点DID模型实证检验开发区升格政策对企业创新数量和创新质量的影响,结果表明:省级开发区升格通过降低制度性交易成本、提升市场化程度和加速创新要素流入对企业创新产出数量和产出质量产生促进作用,该政策对非民营企业、非高技术制造行业、高新区和小规模城市的作用效果更强。因此,要充分发挥开发区“以升促建”的创新激励效应,不仅要注重有为政府和有效市场的结合,还要根据城市固有经济特征优化开发区制度环境。

关键词：开发区升格创新数量创新质量

Preparation and optical properties of Y_2O_3/SiO_2 powder

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Rare Metals 2011年第1期30卷 33-38页

作者： SHEN xiaoyi ZHAI Yuchun School of Materials and Metallurgy Northeastern UniversityShenyang 110819China

Y（NO3）3 and NH3·H2O were used as a raw materials,and nano-Y2O3 powder was successfully synthesized by a precipitation *** TEOS as a raw material,SiO2 powder was successfully prepared by a alkoxide-hydrolysis method,and a Y2O3/SiO2 composite powder was obtained by *** Y2O3,SiO2,and Y2O3/SiO2 powders were characterized using X-ray diffraction（XRD）,scanning electron microscopy（SEM）,and Fourier transform infrared spectrophotometer（FT-IR）;the Y2O3 and Y2O3/SiO2 powders were further examined by photoluminescence（PL） *** results indicated that the Y2O3 powder had a body-centered cubic structure with an average size of 35 nm,while the SiO2 powder was amorphous,with an average size of 145 nm and a narrow size *** PL spectra of the Y2O3 and Y2O3/SiO2 powders showed that their wavelength of emission spectra were 585 nm,while their wavelength of excitation spectra were in the range of 240-260 *** optical properties of the Y2O3/SiO2 powder were identical to the Y2O3 powder.

关键词： powders composite materials yttrium oxide silicon oxide optical properties

Swelling and instability of a gel annulus

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Acta Mechanica Sinica 2015年第5期31卷 627-636页

作者： xiaoyi Chen Hui-Hui Dai Department of Mathematics City University of Hong Kong

We study the swelling of a gel annulus attached to a rigid core when it is immersed in a *** equilibrium states,the free-energy function of the gel can be converted into a strain energy function,and as a result the gel can be treated as a compressible hyperelastic *** methods are used to study the inhomogeneous swelling in order to obtain the leading-order *** analytical insights are then *** of the compressive hoop stress in this state,at some stage instability can occur,leading to wrinkles in the *** incremental deformation theory in nonlinear elasticity is used to conduct a linear bifurcation analysis for understanding such *** specifically,the critical loading for the onset of a wrinkled state is *** discussions on the behaviors of various physical quantities in this critical state are *** is found that the critical mode number,while insensitive to the material parameters,is greatly influenced by the ratio of the inner and outer radii of the ***,an interesting finding is that the critical swelling ratio is an increasing function of this geometrical parameter,which implies that a thin annulus is more likely to be unstable than a thick one.

关键词： gel Wrinkle Linear bifurcation analysis

The Necessary and Sufficient Conditions of Exponential Stability for Heat and wave Equations with Memory

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Journal of Systems Science & Complexity 2024年第3期37卷 1037-1051页

作者： LI Lingfei ZHANg xiaoyi ZHOU Xiuxiang School of Science Northeast Electric Power UniversityJilin 132012China School of Mathematics and Statistics Lingnan Normal UniversityZhanjiang 524048China

This paper is addressed to a study of the stability of heat and wave equations with *** necessary and sufficient conditions of the exponential stability are investigated by the theory of Laplace transform. The results show that the stability depends on the decay rate and the coefficient of the kernel functions of the memory. Besides, the feedback stabilization of the heat equation is obtained by constructing finite dimensional controller according to unstable eigenvalues. This stabilizing procedure is easy to operate and can be applicable for other parabolic equations with memory.

关键词： Memory stability stabilization

Electronic polarization in dipolar organic molecular semiconductors:The case study of 1,2,3,4-tetrafluoro-6,7-dimethylnaphthalene crystal

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Chinese Chemical Letters 2020年第3期31卷 797-800页

作者： xiaoyi Ma Yuanping Yi Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Organic SolidsCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy Sciences Beijing 100049China

Electronic polarization has an important impact on the site energies of charge carriers that play a key role in determining the charge transport in organic *** molecules have strong intermolecular interactions and widespread applications in organic *** r,compared with nonpolar organic semiconductors,electronic polarization for dipolar systems has been rarely ***,taking 1,2,3,4-tetrafluoro-6,7-dimethylnaphthalene as representative,we have calculated the electronic polarization energies of dipolar organic molecular crystals by means of a polarizable forcefield ***,our results point to that the polarization energies for this dipolar system are similar to those of nonpolar *** addition,theπ-πstack contributes only about 30%~40%to the total polarization energy,thus the polarization effects along the three dimensions should be treated equally even for the one-dimensional stacking crystals.

关键词： Electronic polarization Dipolar Organic semiconductors Charge transport Polarizable force field

An analysis method for ISL of multilayer constellation

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Journal of Systems Engineering and Electronics 2022年第4期33卷 961-968页

作者： XU xiaoyi wa.g Chunhui JIN Zhonghe Micro-Satellite Research Center Zhejiang UniversityHangzhou 310027China

The multilayer satellite network has high spatial spectrum utilization, flexible networking, strong survivability, and diversified functions. The inter-satellite links(ISLs) and crosslayer ISLs(CLISLs) enable direct communication paths between satellites, which improves the spatial autonomy of the constellation. Due to the existence of perturbation, ISLs are affected for a long time, which impacts reliable inter-satellite transmission. The stability and complexity of ISL establishment are related to the static and dynamic characteristics of range and azimuth. This paper presents a model of ISLs in a perturbed multilayer constellation. Series of theoretical derivation, simulation, and numerical calculation are carried out. A more comprehensive multilayer constellation ISL model is obtained. The work of this paper provides some theoretical foundations for constellation networking research.

关键词： satellite network multilayer constellation inter-satellite link(ISL)

Epilepsy: Quality of life and assessment scale evaluation

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Neural Regeneration Research 2008年第1期3卷 83-88页

作者： Fayun Hu xiaoyi Zou Department of Neurology West China Hospital Sichuan University Chengdu 610041 Sichuan Province China

BACKgROUND： Quality of life （QOL） is an important topic in current international research of epilepsy. In countries other than China, QOL in epilepsy has been well studied, and many assessment scales or QOL of epilepsy have been developed and used in the clinical practice. In China, concern for QOL of epilepsy patients is very recent, and QOL assessment scales, which correspond to China＇s basic conditions, are still needed. OBJECTIVE： This review aimed to analyze the primary influencing factors and assessment scales of QOL in epilepsy, to investigate the topics of current and future research for QOL of epilepsy patients, and to highlight the importance of QOL for epilepsy patients, according to China＇s basic conditions. RETRIEVAL STRATEgY： Using the terms ＂quality of life in epilepsy＂, we computer-retrieved from the PubMed （http：//***/PubMed） database human studies published between January 1998 and April 2007 in the English language. A total of 745 manuscripts were searched, of which 243 were review papers. At the same time, we computer-searched the China National Knowledge Infrastructure with the terms ＂epilepsy and quality and life＂ in the Chinese language for studies published between 2002 and 2007. Altogether, 181 Chinese literatures were retrieved, 32 of which were from high-impact journals. LITERATURE EVALUATION： The retrieved manuscripts were initially selected, but 50 were kept for further analysis. The selected manuscripts were as follows： 31 Chinese and/or English studies addressed the influencing factors of QOL for epilepsy patients, as well as assessment scales for QOL in different populations of epilepsy patients, of which 5 were review articles and the remaining 26 were clinical studies; and 19 Chinese and/or English literatures were rejected, because they were not in accordance with the inclusive criteria. DATA SYNTHESIS： QOL for epilepsy patients is an emerging field. At present, ＂the Liverpool group model for determining QOL in peo

关键词： epilepsy quality of life China.

Subinterval Decomposition-Based Interval Importance Analysis Method

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Computer Modeling in Engineering & Sciences 2020年第9期124卷 985-1000页

作者： Wenxuan wa.g xiaoyi wa.g School of Mechatronic Engineering Lanzhou Jiaotong UniversityLanzhou730070China

The importance analysis method represents a powerful tool for quantifying the impact of input uncertainty on the output *** an input variable is described by a specific interval rather than a certain probability distribution,the interval importance measure of input interval variable can be calculated by the traditional non-probabilistic importance analysis ***,the non-probabilistic importance analysis methods involve the Monte Carlo simulation(MCS)and the optimization-based methods,which both have high computational *** order to overcome this problem,this study proposes an interval important analytical method avoids the time-consuming optimization ***,the original performance function is decomposed into a combination of a series of one-dimensional ***,the interval of each variable is divided into several subintervals,and the response value of each one-dimensional subsystem at a specific input point is ***,the obtained responses are taken as specific values of the new input variable,and the interval importance is calculated by the approximated performance *** with the traditional non-probabilistic importance analysis method,the proposed method significantly reduces the computational cost caused by the MCS and optimization *** the proposed method,the number of function evaluations is equal to one plus the sum of the subintervals of all of the *** efficiency and accuracy of the proposed method are verified by five *** results show that the proposed method is not only efficient but also accurate.

关键词： Importance analysis method interval variable subinterval decomposition performance function MCS