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Journal of Integrative Agriculture 2024年第2期23卷 457-467页

作者： Mosses Lufuke xu Tian college of economics and Management Nanjing Agricultural UniversityNanjing 210095China department of economics The University of DodomaDodoma 41218Tanzania college of economics and Management China Agricultural UniversityBeijing 100083China Academy of Global Food economics and Policy China Agricultural UniversityBeijing 100083China

Despite the growing recognition of women’s increasing role in the household and corresponding empowerment programs in sub-Saharan Africa,intensive research on the relationship between women’s influence and household food consumption is *** the most recent(2017-2018)national household survey data from Tanzania,this study examined the influence of women’s empowerment on household food ***,we compared the monthly consumption of eight food categories between female-headed households(FHHs)and male-headed households(MHHs)using both descriptive statistics and the propensity score matching(PSM)***,we adopted the two-stage Linear Expenditure System and Almost Ideal Demand System model(LES-AIDS)to estimate income and price elasticities for the two household *** results show that FHHs consume bread and cereals,fish,oils and fats,vegetables,and confectionery(sugar,jam,honey,chocolate,etc.)more than ***,FHHs have a significantly higher income elasticity of demand for all food groups than *** are also more price elastic than MHHs in meat,fish,oils,fats,sugar,jam,honey,chocolate,etc.

关键词： women’s empowerment food consumption income elasticity price elasticity

Portable spirometer-based pulmonary function test willingness in China: A nationwide cross-sectional study from the "Happy Breathing Program"

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中华医学杂志(英文版) 2024年第14期137卷 1695-1704页

作者： Qi Weiran Huang Ke Chen Qiushi Jiao Lirui Yu Fengyun Yu Yiwen Niu Hongtao Li Wei Fang Fang Lei Jieping Chu xu Li Zilin Geldsetzer Pascal B?rnighausen Till Chen Simiao Yang Ting Wang Chen department of Health economics and Health Policy School of Population Medicine and Public Health Chinese Academy of Medical Sciences and Peking Union Medical College Beijing China department of Pulmonary and Critical Care Medicine National Center for Respiratory Medicine State Key Laboratory of Respiratory Health and Multimorbidity National Clinical Research Center for Respiratory Diseases Institute of Respiratory Medicine Chinese Academy of Medical Sciences Center of Respiratory Medicine China-Japan Friendship Hospital Beijing China The Harold and Inge Marcus department of Industrial and Manufacturing Engineering The Pennsylvania State University University Park PA USA department of Health Policy and Management Gillings School of Global Public Health University of North Carolina at Chapel Hill Chapel Hill NC USA Heidelberg Institute of Global Health (HIGH) Faculty of Medicine and University Hospital Heidelberg University Heidelberg Germany Administration Office of Medical Reform and Development China-Japan Friendship Hospital Beijing China Data and Project Management Unit Institute of Clinical Medical Sciences China-Japan Friendship Hospital Beijing China department of statistics School of Mathematics and Statistics Northeast Normal University Changchun Jilin China Chan Zuckerberg Biohub Stanford University School of Medicine San Francisco CA USA Division of Primary Care and Population Health Department of Medicine Stanford University School of Medicine Stanford CA USA Harvard Center for Population and Development Studies Harvard T.H. Chan School of Public Health Harvard University Cambridge MA USA

Background: Understanding willingness to undergo pulmonary function tests (PFTs) and the factors associated with poor uptake of PFTs is crucial for improving early detection and treatment of chronic obstructive pulmonary disease (COPD). This study aimed to understand willingness to undergo PFTs among high-risk populations and identify any barriers that may contribute to low uptake of ***: We collected data from participants in the "Happy Breathing Program" in China. Participants who did not follow physicians’ recommendations to undergo PFTs were invited to complete a survey regarding their willingness to undergo PFTs and their reasons for not undergoing PFTs. We estimated the proportion of participants who were willing to undergo PFTs and examined the various reasons for participants to not undergo PFTs. We conducted univariable and multivariable logistic regressions to analyze the impact of individual-level factors on willingness to undergo ***: A total of 8475 participants who had completed the survey on willingness to undergo PFTs were included in this study. Out of these participants, 7660 (90.4%) were willing to undergo PFTs. Among those who were willing to undergo PFTs but actually did not, the main reasons for not doing so were geographical inaccessibility (n = 3304, 43.1%) and a lack of trust in primary healthcare institutions (n = 2809, 36.7%). Among the 815 participants who were unwilling to undergo PFTs, over half (n = 447, 54.8%) believed that they did not have health problems and would only consider PFTs when they felt unwell. In the multivariable regression, individuals who were ≤54 years old, residing in rural townships, with a secondary educational level, with medical reimbursement, still working, with occupational exposure to dust, and aware of the abbreviation "COPD" were more willing to undergo ***: Willingness to undergo PFTs was high among high-risk populations. Policymakers may consider implementing strategies suc

关键词： Chronic obstructive pulmonary disease Pulmonary function tests Willingness to undergo pulmonary function tests Population medicine

OPTIMAL INVESTMENT WITH NOISE TRADING RISK

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Journal of Systems Science & Complexity 2008年第4期21卷 519-526页

作者： Yunhui xu Zhongfei LI Ken Seng TAN Lingnan college Sun Yat-Sen University Guangzhou 510275 China department of statistics and Actuarial Science University of Waterloo Waterloo Ontario N2L 3G1 Canada. Lingnan college Sun Yat-Sen University Guangzhou 510275 China department of statistics and Actuarial Science University of Waterloo Waterloo Ontario N2L 3G1 Canada China Institute for Actuarial Science Central University of Finance and Economics Beijing 100081 China.

This paper investigates the optimal dynamic investment for an investor who maximizes constant absolute risk aversion （CARA） utility in a discrete-time market with a riskfree bond and a risky stock. The risky stock is assumed to present both the dividend risk and the price risk. With our assumptions, the dividend risk is equivalent to fundamental risk, and the price risk is equivalent to the noise trading risk. The analytical expression for the optimal investment strategy is obtained by dynamic programming. The main result in this paper highlights the importance of differentiating between noise trading risk and fundamental risk for the optimal dynamic investment.

关键词： Dynamic investment noise trade overlapping generation serial correlation.

Adjoining Batch Markov Arrival Processes of a Markov Chain

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Acta Mathematicae Applicatae Sinica 2018年第1期34卷 1-10页

作者： Xiao-yun MO xu-yan XIANG Xiang-qun YANG college of Mathematics and statistics Hunan University of Finance and Economics Changsha 410205 China college of Mathematics and Computational Science Hunan University of Arts and Science Changde 415000 China Key Laboratory of High performance Computing and Stochastic Information Processing Ministry of Education of China College of Mathematics and Computer Science Hunan Normal University Changsha 410081 China Hunan Province Cooperative Innovation Center for the Construction and Development of Dongting Lake Ecological Economic Zone Changde 415000 China

A batch Markov arrival process（BMAP） X^＊=（N, J） is a 2-dimensional Markov process with two components, one is the counting process N and the other one is the phase process J. It is proved that the phase process is a time-homogeneous Markov chain with a finite state-space, or for short, Markov chain. In this paper,a new and inverse problem is proposed firstly： given a Markov chain J, can we deploy a process N such that the 2-dimensional process X^＊=（N, J） is a BMAP？ The process X^＊=（N, J） is said to be an adjoining BMAP for the Markov chain J. For a given Markov chain the adjoining processes exist and they are not unique. Two kinds of adjoining BMAPs have been constructed. One is the BMAPs with fixed constant batches, the other one is the BMAPs with independent and identically distributed（i.i.d） random batches. The method we used in this paper is not the usual matrix-analytic method of studying BMAP, it is a path-analytic method. We constructed directly sample paths of adjoining BMAPs. The expressions of characteristic（D_k, k = 0, 1, 2· · ·）and transition probabilities of the adjoining BMAP are obtained by the density matrix Q of the given Markov chain J. Moreover, we obtained two frontal Theorems. We present these expressions in the first time.

关键词： Markov chain batch Markov arrival process (BMAP) adjoining BMAP fixed constant batch independent identically distributed (i.i.d) random batch

露天煤矿人工林植被碳密度分配格局及其影响因素

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干旱区研究 2024年第6期41卷 974-983页

作者：张建华周晓阳郭旭婷杜鑫鑫安利秦浩刘勇张红徐龙超忻州师范学院生物系山西忻州034000 太原理工大学生态学学院山西太原030024 山西财经大学统计学院山西太原030006 山西大学黄土高原研究所山西太原030006

定量研究露天煤矿人工林植被碳密度分配格局及其影响因素,进而为矿区森林碳汇服务功能的提升提供数据基础。本研究以安太堡矿区排土场油松(Pinus tabulaeformis)、小叶杨(Populus microphylla)、加拿大杨(Populus canadensis)、刺槐(Rob... 详细信息

定量研究露天煤矿人工林植被碳密度分配格局及其影响因素,进而为矿区森林碳汇服务功能的提升提供数据基础。本研究以安太堡矿区排土场油松(Pinus tabulaeformis)、小叶杨(Populus microphylla)、加拿大杨(Populus canadensis)、刺槐(Robinia pseudoacacia)、榆树(Ulmus pumila)和刺槐-榆树混交林为研究对象,基于样地本底调查和异速生长方程法,测定了不同人工林的碳密度及空间分布格局。加拿大杨林植被碳密度(36.95 t·hm-2)显著高于其他人工林(P凋落物层>草本层、灌木层(P<0.05),其中,乔木层碳密度占植被碳密度的78.3%~93.6%,表明人工林植被碳密度以乔木层为主;人工林乔木层树干中碳密度显著高于根、枝和叶(P<0.05),加拿大杨林树干碳密度显著高于刺槐林和刺槐-榆树混交林,密植油松林显著高于疏植油松林。乔木层和凋落物层碳密度均与林分密度显著正相关,与草本高度和盖度显著负相关,且乔木层碳密度与乔木高度显著正相关(P<0.05)。从固碳功能来看,安太堡煤矿排土场复垦合理密植油松和加拿大杨,有利于矿区的生态恢复,从而实现生态环境安全的可持续发展。

关键词：碳密度生物量人工林植被恢复安太堡煤矿

中国数字经济企业技术创新的区域差异及其时空演进

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浙江树人学院学报 2024年第2期24卷 65-76页

作者：肖明月方倩徐晓慧杨君浙江理工大学经济管理学院浙江杭州310018 浙江金融职业学院发展规划处浙江杭州310018

基于国家统计局最新标准匹配数字经济企业,综合运用多种研究方法,分析中国数字经济企业技术创新的区域差异及其时空演进特征。Dagum基尼系数显示,数字经济企业技术创新的总体差异呈波动上升态势,区域间差异是总体差异的主要来源,贡献率... 详细信息

基于国家统计局最新标准匹配数字经济企业,综合运用多种研究方法,分析中国数字经济企业技术创新的区域差异及其时空演进特征。Dagum基尼系数显示,数字经济企业技术创新的总体差异呈波动上升态势,区域间差异是总体差异的主要来源,贡献率均值达68.31%;从区域内差异上看,仅东部沿海和长江中游地区存在收敛趋势;从区域间差异上看,沿海—内陆之间的差异最大,沿海—沿海次之,内陆—内陆最小。Markov链概率转移矩阵显示,数字经济企业技术创新呈现出低水平和高水平状态相对稳定、中水平状态波动强的特征,且跨状态转移比例远低于邻近状态转移,说明数字经济企业技术创新跨越式发展难度较大。Moran指数显示,数字经济企业技术创新存在空间负相关性且保持较强的空间稳定性。α和β收敛分析显示,数字经济企业技术创新的发散态势显著,且区域间存在负向空间溢出效应。上述结论可为中国数字经济创新发展和区域协同增长政策制定提供启示。

关键词：数字经济技术创新区域差异时空演进

Varying coefficient analysis for indeterminate species interactions with non-parametric estimation, exemplifying with a fig-fig wasp system

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Chinese Science Bulletin 2011年第24期56卷 2545-2552页

作者： SHI Lei WANG RuiWu ZHU LiXing ZEN WeiMing xu WangLi ZHENG Qi statistics and Mathematics School Yunnan University of Finance and Economics Kunming 650221 China Ecology Conservation and Environment Center (ECEC) State Key Laboratory of Genetic Resources and Evolution Kunming Institute of Zoo-logy Chinese Academy of Sciences Kunming 650223 China department of Mathematics Hong Kong Baptist University Hong Kong China Scientific and Technical department Yunnan University of Nationalities Kunming 650031 China statistics college RenMing University of China Beijing 100080 China

Research on species interactions has generally assumed that species have a fixed interaction and therefore linear or non-linear parametric regression models (e.g. exponential, logistic) have been widely used to describe the species interaction. However, these models that describe the relationship between interacting species as a specific functional response might not be appropriate for real biological communities, for instance, in a chaotic system, when the species relationship varies among different situations. To allow a more accurate description of the relationship, we developed a species correlation model with varying coefficient analysis, in which a non-parametric estimation is applied to identify, as a function of related factors, variation in the correlation coefficient. This was applied to a fig-fig wasp model system. When the effect of the factors on the relationship can be described with parameters, the new method reduces to traditional parametric correlation analysis. In this way, the new method is more general and flexible for empirical data analyses, but different by allowing investigation of whether a species interaction varies with respect to factors, and of the factors that maintain or change the species interaction. This method will have important applications in both theoretical and applied research (e.g. epidemiology, community management).

关键词：相互作用系数非参数估计混沌系统无花果物种非线性参数例证小蜂

A Non-Singleton Type-3 Fuzzy Modeling: Optimized by Square-Root Cubature Kalman Filter

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Intelligent Automation & Soft Computing 2023年第7期37卷 17-32页

作者： Aoqi xu Khalid A.Alattas Nasreen Kausar Ardashir Mohammadzadeh Ebru Ozbilge Tonguc Cagin School of economics Fujian Normal UniversityFuzhou350007China department of Computer Science and Artificial Intelligence College of Computer Science and EngineeringUniversity of JeddahJeddah23890Saudi Arabia department of Mathematics Faculty of Arts and ScienceYildiz Technical UniversityEsenler34220IstanbulTurkey Multidisciplinary Center for Infrastructure Engineering Shenyang University of TechnologyShenyang110870China American University of the Middle East Department of Mathematics&Statistics54200EgailaKuwait

In many problems,to analyze the process/metabolism behavior,a mod-el of the system is identiﬁ*** main gap is the weakness of current methods *** *** primary objective of this study is to present a more robust method against *** paper proposes a new deep learning scheme for modeling and identiﬁcation *** suggested approach is based on non-singleton type-3 fuzzy logic systems(NT3-FLSs)that can support measurement errors and high-level *** the rule optimization,the antecedent parameters and the level of secondary memberships are also adjusted by the suggested square root cubature Kalmanﬁlter(SCKF).In the learn-ing algorithm,the presented NT3-FLSs are deeply learned,and their nonlinear structure is *** designed scheme is applied for modeling carbon cap-ture and sequestration problem using real-world data *** various ana-lyses and comparisons,the better efﬁciency of the proposed fuzzy modeling scheme is veriﬁ*** main advantages of the suggested approach include better resistance against uncertainties,deep learning,and good convergence.

关键词： Modeling computational intelligence fuzzy logic systems modeling identiﬁcation deep learning type-3 fuzzy systems optimization

Dynamic changes and convergence of China's regional green productivity:A dynamic spatial econometric analysis

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Advances in Climate Change Research 2022年第2期13卷 266-278页

作者： xu-Quan ZHAI Rui xuE Bin HE Dong YANG Xiang-Yu PEI Xian LI Yuli SHAN Research Center for Socialism with Chinese Characteristics Zhejiang UniversityHangzhou 310058China Centre for Corporate Sustainability and Environmental Finance Department of Applied FinanceMacquarie UniversitySydney 2109Australia China Center for Public Sector Economic Research Jilin UniversityChangchun 130012China School of statistics Southwestern University of Finance and EconomicsChengdu 611130China School of economics Jilin UniversityChangchun 130012China college of Textile Donghua UniversityShanghai 201620China Integrated Research on Energy Environment and Society(IREES)Energy and Sustainability Research Institute GroningenUniversity of GroningenGroningen 9747 AGthe Netherlands

Low-carbon economic development is at the heart of the post-pandemic green recovery scheme *** requires economic recovery without compromising on the environment,implying a critical role that green productivity plays in achieving the carbon neutrality *** productivity measures the quality of economic growth with consideration for energy consumption and environmental *** study employs the slacks-based measure directional distance function(SBM-DDF)approach and the Malmquist-Luenberger(ML)index to calculate green productivity and its components of 30 provinces in China between 2001 and *** a spatial panel data model,we empirically analyzed the conditionalβ-convergence of China's green *** found that overall,since 2001,China's green productivity has demonstrated a continuous upward *** taking into account spatial factors,China's green productivity demonstrates a significant conditionalβ-*** terms of regional effects,the results indicate that the green productivity of the eastern and western regions demonstrates club convergence,implying a more balanced green economic ***,the convergence rate of China's green productivity increases with the addition of environmental regulation variable,and so the corresponding convergence time *** indicates that environmental regulations help to facilitate the convergence of China's green productivity,narrowing the gap between the regional green economic *** findings provide guideline for achieving a low-carbon development and carbon neutrality from a regional green productivity perspective.

关键词： Green productivity Slacks-based measure of directional distance function(SBM-DDF) Malmquist-Luenberger(ML)index Conditionalβ-convergence Spatial econometrics Carbon neutrality