The Age Distribution Model and the Parity Progressive Model of Population and Their Equivalence

This paper proved that the integral form and the intero-differential form of the agestructured population equation(Lotka model) are equivalent, the integral form and the integrodifferential form of the parity prongressive population equation(Henry model)are equivalent. By the age parity progressive model, the equivalence between Lotka model and Henry Model is also proved. Moreover. the relation between the parity progression ratio and the total fertility rate is giver.     

CRITICAL BIRTH ORDER RATIO CONTROL AND ATTAINABLE SET OF A DISCRETE AGE－DEPENDENT PARITY PROGRESSION POPULATION SYSTEM

ＣＲＩＴＩＣＡＬＢＩＲＴＨＯＲＤＥＲＲＡＴＩＯＣＯＮＴＲＯＬＡＮＤＡＴＴＡＩＮＡＢＬＥＳＥＴＯＦＡＤＩＳＣＲＥＴＥＡＧＥ－ＤＥＰＥＮＤＥＮＴＰＡＲＩＴＹＰＳＯＧＲＥＳＳＩＯＮＰＯＰＵＬＡＴＩＯＮＳＹＳＴＥＭＧＵＯＢａｏｚｈｕ（Ｄｅｐａｒｔｍｅｎｔｏｆ...     

洞庭湖区东方田鼠种群生长与灾变过程建模与仿真分析

根据洞庭湖区东方田鼠的生物特性和周围生态环境的特点,建立了具有年龄结构的洞庭湖区东方田鼠种群增长离散模型。通过模型的稳定性和仿真分析,探讨了洞庭湖区东方田鼠种群增长的一般性规律及其灾变过程。研究结论对洞庭湖区东方田鼠历年频频爆发成灾给出了合理解释,并对鼠灾的最佳防治策略提出了建议。     

THE EQUILIBRIA OF THE SIZE STRUCTURED POPULATION MODEL

In this paper the existence and stability of the positive equilibrium of the size-structured population model are proved by Rabinowitz‘s theorem and the local linearization method.The result here shows that near the bifurcation point where a branch of positive equilibria appears,the stability of the positive equilibrium on the branch is dcpendent on the direction of the bifurcation.The argument for the model of age-structured population is generalized in this paper.     

Global stability for a heroin model with age-dependent susceptibility

This paper considers global asymptotic properties for an age-structured model of heroin use based on the principles of mathematical epidemiology where the incidence rate depends on the age of susceptible individuals. The basic reproduction number of the heroin spread is obtained. It completely determines the stability of equilibria. By using the direct Lyapunov method with Volterra type Lyapunov function, the authors show that the drug-free equilibrium is globally asymptotically stable if the basic reproduction number is less than one, and the unique drug spread equilibrium is globally asymptotically stable if the basic reproduction number is greater than one.     

Global stability of an age-structured sir epidemic model with pulse vaccination strategy

This paper discusses the application of a pulse vaccination strategy to prevent and control some infectious diseases,which is described by age-structured SIR model in which susceptible and recovered individuals are structured by chronological age,while infected individuals are structured by infection age(duration since infection).The time dependent disease-free equilibrium is determined, for which an explicit expression exists.The analytical results show that there exists a globally stable infect ion-free situation if the impulsive period T and proportion p satisfy Ro(p,T) < 1.Optimal problem is discussed:Pulse vaccination strategy with minimal costs at given Ro(p,T) < 1.     

农村分性别户籍人口年龄结构统计数据修正——————以陕西省宝鸡市陈仓区为例

农村分性别户籍人口年龄结构统计数据是研究农村问题的基础数据, 文章以农村分性别户籍人口年龄结构调查数据作为对照组, 基于设定相对误差界限前提下的对比分析方法确定需修正的年龄组, 构建农村分性别户籍人口统计数据修正模型, 并运用该模型对陕西省宝鸡市陈仓区农村分性别户籍人口年龄结构统计数据进行修正, 修正结果表明, 相对误差界限取10%时, 修正后陈仓区农村户籍人口总量比统计总量多3.65%, 其中男性多1.99%, 女性多5.43%; 相对误差界限取5%时, 修正后陈仓区农村户籍人口总量比统计总量多3.70%, 其中男性多3.59%, 女性多3.83%. 文章为农村户籍人口数据修正提供了基本方法, 所得结论为精确研究农村社会问题提供了基础资料.     

EXISTENCE AND UNIQUENESS OF ENDEMIC STATES FOR THE AGE-STRUCTURED SEIR EPIDEMIC MODEL

An age-structured SEIR epidemic model of a vertically as well as horizontally transmitteddisease is investigated.Threshold results for the existence of endemic states are established for mostcases.Under certain conditions,uniqueness is also shown.Threshold used are explicitly computablein term of demographic and epidemiological parameters of the model.     

中国人口年龄结构变化及其对社会经济的影响

讨论中国特有的人口年龄结构变化特征及其对我国社会经济的影响问题．     

1991－2010年间中国人口生育基数

为了较为准确地估计今后我国生育基数,本文分析了女性死亡率、生育模式和女性年龄结构对生育基数预测的影响,并利用1988年全国千分之二抽样调查、1990年人口普查和1992年38万全国抽样调查的数据资料进行数据处理,给出了1991-2010年间全国人口生育基数计算结果。     

传染病传播模型综述

建立传染病传播模型是理解传染病流行机理, 预测流行趋势, 进行防控决策的基础. 将传染病传播模型分为单一群体模型, 复合群体模型和微观个体模型三类. 单一群体模型从宏观角度刻画了集计量的变化, 以经典的\,SIR\,为基础, 在仓室设置、 年龄结构、 随机性、 异质性等方面进行了扩展. 复合群体模型将人群划分为多个子群体, 子群体之间因人口流动而耦合, 适合研究具有空间异质性的跨地区传播问题. 微观个体模型的出发点是个体状态和行为, 所有个体形成接触网络. 这类模型有理想网络和现实网络两个研究方向, 理想网络关注接触网络特性对传染病传播动力学的影响, 现实网络致力于揭示社会接触的实际特征, 构建足够真实的模拟网络, 研究传染病的传播. 这三类模型各有特点, 分别具有各自的适用领域, 应根据研究目的和问题特点选择合适的建模方法.     

辽宁省人口结构与经济协调发展研究

人口结构与经济发展相互影响、相互制约,两者的协调发展是实现区域可持续发展的重要途径。建立人口结构与经济协调度的评价指标体系、模型和方法,并对辽宁省进行了实证研究。研究表明,1995年以来辽宁省人口结构与经济协调发展呈现“倒u”型曲线：2000年以前,人口结构与经济协调发展状况由初级协调向高级协调转化;2000年以后,两者的协调发展状况却有不断下降的趋势。图2,表4,参12。     

中国城乡迁移年龄模式的研究

分析了中国１９９０年人口普查问卷中迁移项目的特点,指出从原始数据估计迁移人口迁移年龄的困难及克服此困难所必须引入的假定,提出了在较弱的假定下估计各种按龄迁移人口及按龄人口迁移率的方法。据此方法可得出１９８５年到１９８９年四年间平均按龄迁移量、平均按龄人口数及平均按龄迁移率。作为应用,对“四普”中城乡人口迁移的年龄模式进行了分析,并与联合国人口迁移的年龄模式进行了比较,发现中国城乡迁移特殊的年龄模式     

1998-based national population projections for the United Kingdom and constituent countries

The 1998-based national population projections, carried out by the Government Actuary in consultation with the Registrars General, show the population of the United Kingdom rising from 59.2 million in 1998 to over 63.5 million by 2021. Longer-term projections suggest the population will peak around 2036 and then gradually start to fall. The population will become gradually older with the median age expected to rise from 36.9 years in 1998 to nearly 42 years by 2021. In 1998, there were 1.4 million (13 per cent) more children aged under 16, than people of pensionable age. However, by 2008, the population of pensionable age is projected to exceed the number of children.     

2002-based national population projections for the United Kingdom and constituent countries

The 2002-based national population projections, carried out by the Government Actuary in consultation with the Registrars General, show the population of the United Kingdom rising from 59.2 million in 2002 to nearly 65 million by 2031. Longer-term projections suggest the population will peak around 2050 at over 65 million and then gradually start to fall. The population will become gradually older with the median age expected to rise from 38.2 years in 2002 to 43.3 years by 2031. In 2002, there were around 850 thousand (8 per cent) more children aged under 16, than people of state pensionable age. However, from 2007, the population of pensionable age is projected to exceed the number of children.     

2004-based national population projections for the UK and constituent countries

The 2004-based national population projections, carried out by the Government Actuary in consultation with the Registrars General, show the population of the United Kingdom (UK) rising from 59.8 million in 2004, passing 60 million in 2005 and 65 million in 2023, to reach 67.0 million by 2031. In the longer-term, the projections suggest that the population will continue rising beyond 2031 but at a much lower rate of growth. The population will become older with the median age expected to rise from 38.6 years in 2004 to 42.9 years by 2031. With the current plans for a common state pension age of 65 for both sexes from 2020, the number of people of working age for every person of state pensionable age is projected to fall from 3.33 in 2004 to 2.62 by 2031.     

2006-based national population projections for the U.K. and constituent countries

The 2006-based national population projections, carried out by the Office for National Statistics in consultation with the devolved administrations, show the population of the UK rising from 60.6 million in 2006, passing 65 million in 2016 and 70 million in 2028, to reach 71.1 million by 2031. In the longer-term, the projections suggest that the population will continue rising beyond 2031 for the full length of the projection period. The population will become older with the median age expected to rise from 39.0 years in 2006 to 41.8 years by 2031. Since the last projection round legislation has been passed to increase the state pension age from 65 to 66 for both sexes between 2024 and 2026. Despite this change, the number of people of working age for every person of state pensionable age will reduce from 3.32 in 2006 to 2.91 by 2031. The legislation includes further increases in the state pension age to 68 for both sexes by 2046.     

基于合理膳食结构的2020-2050年我国食物用粮需求测算

测算我国未来粮食需求量是制定我国粮食安全相关政策措施的基础.目前我国城镇化水平加快,老龄化问题突出,完全二孩生育政策刚刚实施,正处于人口结构转型的关键期,而人口结构变动直接影响食物用粮需求.本文从满足居民营养健康标准的食物需求视角下,考虑人口年龄、性别和城乡结构,采用标准人消费系数法,测算了单独二孩政策、完全二孩政策和完全放开生育政策情景下2020-2050年我国食物用粮（包括口粮与饲料粮）的需求,并进行对比分析.结果表明：在完全二孩政策情景下,我国食物用粮需求将在2030年达到峰值39263.1万吨,比通常采用人均方法的计算结果低10061.0万吨;因城镇化率的提高将使2020、2030与2050年食物用粮需求分别增加约406.7万吨、1142.5万吨与1553.8万吨;生育政策调整所带来的人口规模与结构变化并不是2020-2050年我国粮食安全的主要影响因素.建议积极引导和鼓励生育,在适当时间进一步完全放开生育;同时采取有效措施将粮食损耗与浪费降到最低.     

2000-based national population projections for the United Kingdom and its constituent countries

The 2000-based national population projections, carried out by the Government Actuary at the request of the Registrars General, show the population of the United Kingdom rising from 59.8 million in 2000 to nearly 65 million by 2025. Longer-term projections suggest the population will peak at nearly 66 million around 2040 and then gradually start to fall. The population will become gradually older with the median age expected to rise from 37.4 years in 2000 to 42.4 years by 2025. In 2000, there were 1.3 million (12 per cent) more children aged under 16, than people of state pensionable age. However, by 2007, the population of state pensionable age is projected to exceed the number of children.     

Interim 2003-based national population projections for the United Kingdom and constituent countries

The 2003-based national population projections, carried out by the Government Actuary in consultation with the Registrars General, and using essentially the same underlying assumptions as for the previous 2002-based projections, show the population of the United Kingdom rising from 59.6 million in 2003, passing 60 million during 2005, to reach 65.7 million by 2031. Longer-term projections suggest the population will peak around 2050 at nearly 67 million and then very gradually start to fall. The population will become older with the median age expected to rise from 38.4 years in 2003 to 43.3 years by 2031. In 2003, there were around 700 thousand (six per cent) more children aged under 16, than people of state pensionable age. However, from 2007, the population of pensionable age is projected to exceed the number of children.