scholarly journals Ziebur's matrix equation for population growth

1986 ◽  
Vol 28 (2) ◽  
pp. 220-228
Author(s):  
A. Brown
Keyword(s):  
Population Growth ◽  
Matrix Equation ◽  
Death Rate ◽  
Transition Matrix ◽  
Birth Rate ◽  
Age Groups ◽  
Growth Equation ◽  
Age Dependent ◽  
The Matrix

AbstractThe paper examines a matrix equation given by Ziebur [6] for the growth of a population in which the birth-rate and death-rate are age-dependent. For convenience the population was sub-divided into four age groups, with the same birth-rate and death-rate for individuals in a particular group, and the matrix equation relates the numbers in each sub-division in consecutive years. This avoids delay terms and makes it easier to modify the growth equation but it is shown that the form suggested by Ziebur for the transition matrix leads to some difficulties.

Medical and demographic indicators of the Orenburg Region

2021 ◽  
pp. 65-71
Author(s):  
Lyubov Kuzminichna Grigorieva ◽  
Sergey Aleksandrovich Kuzmin
Keyword(s):  
Life Expectancy ◽  
Population Growth ◽  
Death Rate ◽  
Birth Rate ◽  
Population Decline ◽  
Female Population ◽  
Orenburg Region ◽  
Managerial Decisions ◽  
Demographic Indicators ◽  
Gradual Process

The analysis of the medical and demographic indicators of the Orenburg Region from 2015 to 2019 showed that over this time period, there was a gradual process of population decline. The dynamics of the birth and death rates of the population was characterized by a stable decline. Over a five-year period, the birth rate decreased by 30.78 %, and the death rate by 8.8 %. The natural population growth in 2015 was positive, and since 2016, there has been a negative population growth, i.e. the number of citizens who died annually exceeded the number of births. The region has seen slight changes in the ratio of urban and rural residents. Life expectancy has increased for both sexes from 69.63 years in 2015 to 72.04 years in 2019. The growth of this indicator for men was 4.31 %, and for women — 2.43 %. Studies of the sex composition of the population of the Orenburg Region over the past five years have demonstrated that there have been minor changes in the ratio of the male and female population in the region under study. So, in 2015 and 2016, there were 1149 women per 1000 men; in 2017–1148, in 2018–1147, in 2019–1146. Over the studied period, the number of marriages registered in the Orenburg Region decreased from a maximum of 15418 in 2015 to a minimum of 12304 in 2019, which was 20.2 %. The number of divorces did not decrease so rapidly, from 8,717 maximum in 2015 to 8,424 minimum in 2019, which was 3.36 %. The adoption of managerial decisions aimed at improving the standard of living and health of the population, as well as the environmental situation at the level of legislative and executive authorities will contribute to an increase in life expectancy, reduction in the death rate, and an increase in the birth rate of the population.

Demographic Well-Being: Theoretical Approaches to Definition and Assessment Methodology

2021 ◽  
Vol 1 (4) ◽  
pp. 5-19
Author(s):  
Sergey Ryazantsev ◽  
Timur Miryazov
Keyword(s):  
Population Growth ◽  
Russian Federation ◽  
Birth Rate ◽  
Age Groups ◽  
Its Region ◽  
Well Being ◽  
Demographic Development ◽  
Theoretical Approaches ◽  
The Russian Federation ◽  
The Individual

The article introduces the concept of “demographic well-being”. At the micro level, demographic well-being should be understood as the possibility of realizing matrimonial, reproductive, migration attitudes, which leads to life satisfaction and the achievement of the desired physical, mental, socio-economic state of the individual and the family. Demographic well-being at the level of a country or its region, at the macro level, can be interpreted as a balanced ratio of quantitative and qualitative indicators of the demographic development of a country (region) for at least five years. The article also examines the features of the demographic development of the Russian Federation during the second wave of depopulation. A methodology for assessing demographic well-being based on several criteria is proposed. First, demographic well-being should be characterized by positive (upward) demographic dynamics that have a stable (long-term) character. Secondly, regions in which there is a population growth due to two components – natural and migratory population growth – can be considered demographically prosperous. Regions in which there is a migration or natural decline in population, but there is a general increase, cannot be considered demographically prosperous. Thirdly, the ratio of indicators and the dynamics of fertility and mortality rates can be considered an important point. First of all, this is their direct ratio, where the birth rate should exceed the death rate. At the same time, the birth rate should be close to the population replacement level, and the structure of mortality should have no extreme “surges” in the form of excess mortality in the working age and younger age groups. Fourth, an important point is the qualitative indicators of demographic well-being, including a balanced sex and age structure of the population, the optimal proportion of young people and pensioners, and the availability of labor resources necessary for socio-economic development. The typology of the regions of the Russian Federation according to the indicators of demographic well-being is presented. The authors also propose measures of demographic policy to achieve demographic well-being in the Russian Federation, including federal and regional measures.

Reproductive potential of Gyrodactylus bullatarudis (Monogenea) on guppies (Poecilia reticulata)

Parasitology ◽  
1982 ◽  
Vol 85 (2) ◽  
pp. 217-236 ◽  
Author(s):  
Marilyn E. Scott
Keyword(s):  
Death Rate ◽  
Birth Rate ◽  
Poecilia Reticulata ◽  
Deterministic Model ◽  
Reproductive Potential ◽  
Experimental Conditions ◽  
Average Value ◽  
Age Dependent ◽  
Average Fecundity ◽  
Host Parasite

SUMMARYTwo simple experiments were undertaken using the viviparous ectoparasite, Gyrodactylus bullatarudis, and laboratory-reared guppies, Poecilia reticulata, whereby detailed records of the number and temporal sequence of all births and the age at death were obtained for flukes on isolated guppies. Gyrodactylus bullatarudis has an average fecundity of 1·68 offspring during its expected life-span of 4·20 days. The instantaneous birth rate is independent of generation but dependent on age. The first offspring is born approximately 1 day after the birth of the parent and subsequent offspring are born at 2–2·5 day intervals. The average instantancous birth rate (under given experimental conditions) is 0.43/parasite/day. The death rate increases exponentially with the age of the fluke and has an average value of 0.24/parasite/day. A simple deterministic model incorporating age structure and an age-dependent death rate was found to provide a good fit to the observed exponential increase in G. bullatarudis numbers. The variability observed in this host–parasite system was found to be largely a function of chance, as shown by Monte Carlo simulations of stochastic birth–death processes.

ANALISIS FAKTOR-FAKTOR YANG MEMPENGARUHI PERTUMBUHAN JUMLAH PENDUDUK DI KABUPATEN ACEH TIMUR

2018 ◽  
Vol 9 (1) ◽  
pp. 23-29
Author(s):  
Murtala Murtala
Keyword(s):  
Linear Regression ◽  
Population Growth ◽  
Multiple Linear Regression ◽  
Death Rate ◽  
Birth Rate ◽  
Secondary Data ◽  
Research Problem ◽  
Independent Variables ◽  
The Future ◽  
External Migration

Tujuan penelitian ini adalah untuk mengetahui pengaruh tingkat kelahiran, kematian, migrasi dari luar dan migrasi dari dalam terhadap pertumbuhan jumlah penduduk di Kabupaten Aceh Timur. Data yang digunakan dalam penelitian ini bersumber dari BPS Aceh, BAPPEDA, dan Kantor Bupati serta berbagai literatur dan terbitan berkala lainnya yang ada kaitan dengan masalah penelitian ini. Jenis data yang digunakan adalah data sekunder selama periode 1995-2004 dengan peralatan regresi linear berganda. Hasil penelitian menunjukkan bahwa semua variabel bebas dalam penelitian ini ternyata berpengaruh signifikan terhadap pertumbuhan penduduk di Kabupataen Aceh Timur. Diharapkan pertumbuhan jumlah penduduk di Aceh Timur dimasa yang akan datang terus meningkat dengan harapan tingkat kematian semakin berkurang dan perbaikan gizi semakin baik.AbstractThe purpose of this study was to determine the effect of birth rate, mortality, external migration and inward migration to population growth in East Aceh district. The data used in this research are sourced from BPS Aceh, BAPEDA, and Bupati's Office as well as various other literature and periodical publications related to this research problem. The type of data used is secondary data during the period 1995-2004 with multiple linear regression equipment. The results showed that all independent variables in this study turned out to have a significant effect on population growth in Kabupataen Aceh Timur. It is expected that population growth in East Aceh in the future will continue to increase with the expectation of decreasing death rate and better nutrition improvement.Keywords: birth rate, death, migration from outside, migration from within, population

Population strategies and random environments

1975 ◽  
Vol 53 (2) ◽  
pp. 160-165 ◽  
Author(s):  
Hugh Barclay
Keyword(s):  
Population Growth ◽  
Stochastic Models ◽  
Carrying Capacity ◽  
Death Rate ◽  
Logistic Model ◽  
Birth Rate ◽  
Environmental Variation ◽  
Random Environments ◽  
Probability Of Extinction ◽  
Established Species

It is shown using several models that r and K selection may result from random environmental variation. Probabilities of extinction are derived for both colonizing and well-established species using stochastic models similar to the logistic model, and it is shown that the probability of extinction of a population can be reduced by increasing the birth rate or the carrying capacity or by decreasing the death rate or the effects of the environmental variation on population growth. It is probable that random environmental variation mainly facilitates r selection.

COVID - 19 AND THE PROBLEM OF PERSONALITY

2020 ◽  
pp. 31-35
Author(s):  
Mazaeva N.A. ◽  
Golovina A.G.
Keyword(s):  
General Population ◽  
Age Groups ◽  
Personal Transformation ◽  
Personality Changes ◽  
Age Dependent

In order to determine possible trends in the dynamics and characterological structure of personality in the General population caused by the COVID-19 pandemic, which is a long-term strong stressful effect and clinically and psychopathologically comparable to chronic personality changes after experiencing a disaster, the conditions predisposing to personal transformation, including clinical and prognostic patterns, are analyzed. The age-dependent nature of these changes is shown, and a number of features identified for different age groups are discussed.

Dynamic monitoring of changes in medical and demographic indicators in the Republic of Sakha (Yakutia) from 1998 to 2018

2020 ◽  
pp. 33-36
Keyword(s):  
Mortality Rate ◽  
Population Growth ◽  
Russian Federation ◽  
Rural Population ◽  
Urban Population ◽  
Birth Rate ◽  
Dynamic Monitoring ◽  
Demographic Indicators ◽  
The Russian Federation ◽  
The Republic

We studied the medical and demographic indicators in the Republic of Sakha (Yakutia) for the last 20 years (1998–2018). A decrease in the population by 4,7 % (р<0,01) was revealed in the Russian Federation in the period 1998–2008, 3,4 % decrease, followed by its growth by 2,8 % (р<0,01); a decrease in the number of rural population in the republic and an increase in the urban population were observed. By the beginning of 2019, in comparison with the 2003 data, an increase in the population by 1.9% (р<0,01), a decrease in the number of able-bodied people in the Republic of Sakha (Yakutia) at the beginning of 2019, as compared to 1998, were revealed, by 8,2 %, in the Russian Federation – by 4,7 % (р<0,01). In the Republic of Sakha (Yakutia) the birth rate remains high, the mortality rate is relatively low, and the natural population growth is maintained.

Age and growth pattern of the thin-lipped mullet Liza Ramada in the Eastern coast of Libya.

2016 ◽  
Vol 5 (06) ◽  
pp. 4620
Author(s):  
Manal M. Khalifa ◽  
Ramadan A. S. Ali ◽  
Abdalla N. Elawad* ◽  
Mohammad El. ElMor
Keyword(s):  
Frequency Distribution ◽  
Age Groups ◽  
Age Determination ◽  
Age And Growth ◽  
Eastern Coast ◽  
Growth Equation ◽  
Length Frequency Distribution ◽  
Length Frequency ◽  
Scale Reading ◽  
Von Bertalanffy Growth Equation

Age and growth characteristics of the thin-lipped Grey Mullet (Liza ramada) were investigated in Eastern coast of Libya. Aging was done by two methods: counting annuli on scales and by length frequency distribution, a total of 218 scales were studied for age determination, in addition of 334 fishes specimen for length frequency distribution reading. Four age groups were determined from scale reading, and five age groups from length frequency distribution methods, the parameters of the Von Bertalanffy growth equation for both sex of all individuals were estimated at 35.4 cm, 0.187 per year, -1.14 years and 2.4, for male were estimated at 35.7 cm, 0.17 per year, -1.367 and 2.3, for female were 38.6 cm, 0.156 per year, -1.383 and 2.4, for L∞, k and t0, and φ′, respectively.

scholarly journals Convergence analysis of gradient-based iterative algorithms for a class of rectangular Sylvester matrix equations based on Banach contraction principle

2021 ◽  
Vol 2021 (1) ◽  
Author(s):  
Adisorn Kittisopaporn ◽  
Pattrawut Chansangiam ◽  
Wicharn Lewkeeratiyutkul
Keyword(s):  
Spectral Radius ◽  
Matrix Equation ◽  
Iterative Algorithms ◽  
Banach Contraction Principle ◽  
Contraction Principle ◽  
Convergence Factor ◽  
Sylvester Matrix ◽  
Iteration Matrix ◽  
Banach Contraction ◽  
The Matrix

AbstractWe derive an iterative procedure for solving a generalized Sylvester matrix equation $AXB+CXD = E$ A X B + C X D = E , where $A,B,C,D,E$ A , B , C , D , E are conforming rectangular matrices. Our algorithm is based on gradients and hierarchical identification principle. We convert the matrix iteration process to a first-order linear difference vector equation with matrix coefficient. The Banach contraction principle reveals that the sequence of approximated solutions converges to the exact solution for any initial matrix if and only if the convergence factor belongs to an open interval. The contraction principle also gives the convergence rate and the error analysis, governed by the spectral radius of the associated iteration matrix. We obtain the fastest convergence factor so that the spectral radius of the iteration matrix is minimized. In particular, we obtain iterative algorithms for the matrix equation $AXB=C$ A X B = C , the Sylvester equation, and the Kalman–Yakubovich equation. We give numerical experiments of the proposed algorithm to illustrate its applicability, effectiveness, and efficiency.

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