Population Growth Model Research Articles

Prediction of fine tailings settlement in pit lakes using a population growth model

A model for predicting the settlement trajectory in saturated fluid fine tailings deposits is described. The model uses a population growth function and leverages established theories in soil mechanics, clay–water surface interactions and biogeochemistry to derive compressibility and permeability functions for predicting the settlement behaviour of fine tailings in deep deposits, typical of end pit lakes. The method is particularly useful for tailings treated with flocculants and/or coagulants with continuously changing compressibility and permeability parameters during deposition. For oil sands or mineral sands fluid tailings treated with or without high doses of a coagulant and/or a flocculant, the consolidation parameters determined from the model are comparable with those measured using standardised large-strain consolidation methods, and the predicted settlement using a modified Gibson’s finite-strain equation closely describes the measured settlement and void ratio profiles in geocolumns.

Penerapan Materi Barisan Dan Deret Pada Matematika Ekonomi Terhadap Model Petumbuhan Penduduk

This article discusses the results of research on the application of sequences and series material in economic mathematics to population growth models. Material sequences and series are often used by experts in solving problems related to socio-economics. The purpose of this study was to determine student responses when learning sequences and series in economic mathematics to population growth models, to determine the effectiveness of student knowledge during learning sequences and series material in their understanding of population growth model material. The research method used is quasi-experimental, with a quantitative approach. The population of this study were all students of the Mathematics Education study program and the sample was students of the Mathematics Education study program for the fifth semester Mathematics Economics course at Indraprasta University PGRI which consisted of one class. The research instrument used was observation of student activities to find out the process of learning the material for sequences and series in economic mathematics on population growth models, interviews and filling out Likert-scale questionnaires. Based on an analysis of the completed questionnaire, students responded positively in learning the material for sequences and series in economic mathematics to population growth models. And based on the results of the questionnaire it is known that the learning material for sequences and series is effective in learning population growth models in economic mathematics.

Influencing factors and scenario forecasting of carbon emissions in Liaoning Province, China

Liaoning is a province with large energy consumption and carbon emissions. Management of carbon emissions in Liaoning Province is crucial to realizing China's carbon peaking and carbon neutrality goals. To clarify the driving factors and trends of carbon emissions in Liaoning Province, we analyzed the impacts of six factors on carbon emissions in Liaoning Province through STIRPAT model based on carbon emission data from 1999 to 2019. The impact factors included population, urbanization rate, per-capita GDP, secondary industry ratio, energy consumption per unit GDP, and coal consumption ratio. Nine forecasting scenarios with three economic and population growth models and three emission reduction models were set up, and their carbon emission trends under the above nine forecasting scenarios were predicted. The results showed that the main driving factor of carbon emissions in Liaoning Province was per-capita GDP, and that the main inhibitor was energy consumption per unit GDP. The carbon peak year in Liaoning Province would fluctuate between 2020 and 2055 under the nine forecasting scenarios, with peak values ranging from 544 to 1088 million tons CO2. The medium economic development growth and high carbon emission reduction scenario would be the optimal carbon emission scenario in Liaoning Province. Under this forecasting scenario, Liaoning Province could achieve carbon peak (611 million tons CO2) by 2030 without affec-ting economic development through optimizing energy structure and controlling the intensity of energy consumption. Our results would be helpful for seeking the best path for carbon emission reduction in Liaoning Province and providing a reference for its realization of carbon peaking and carbon neutrality goals.

Extended Kalman filter for fish weight estimation using augmented fish population growth model*

The fish weight, which indicates the growth rate of fish, is a crucial factor that optimizes the feeding rate and shapes the life history of fish in recirculating aquaculture systems. Estimating or predicting fish weight is essential for achieving better control of the output of an aquaculture system. However, many difficulties arise from the lack of direct measurement of fish weight. Currently, aquaculture sensors that directly estimate the fish's weight are unavailable. Additionally, the fish growth model that relies on the fish weight is affected by various environmental factors like water temperature, dissolved oxygen, salinity, and light, increasing the difficulty in estimating the weight. This paper proposes an extended Kalman filter approach for assessing the fish weight from directly available measurements of the fish stocking density and dissolved oxygen. The extended Kalman approach relies on a new version of the fish population growth model, which includes the fish population and dissolved oxygen dynamics. The simulation results demonstrate that the extended Kalman filter algorithm achieves good weight estimation in the nominal case and the presence of process and measurement noises.

EQUATIONS FOR CALCULATING TECHNOLOGICAL PARAMETERS OF PNEUMATIC SORTING MACHINES

The purpose of separation of seed mixtures is the most complete separation of fractions according to the characteristics that ensure the required quality of the resulting final product with the least number of operations. These features are taken into account when creating schematic diagrams of grain-cleaning and sorting machines (separators). Presented the results of a study to determine the indicator for assessing the technological effect of separation by the example of separation of seed mixtures in the ascending air flow of pneumatic sorting machines. (Research purpose) The research purpose is developing a method for calculating the indicator for assessing the technological effect of separation on the separation of seed mixtures in the ascending air flow of pneumatic sorting machines. (Materials and methods) Conducted a study based on the logistician equation and methods of mathematical statistics. (Results and discussion) We considered the logistic equation (the Ferhulst equation by the name of the Belgian mathematician who first formulated it), which initially appeared when studying the population growth model. It was established that the result of measurements of the physico-mechanical properties of seeds (signs of separation) is expressed either in variational series or in variational curves that determine the frequency of a particular seed size of any aggregate. It was shown that from the comparison of these data obtained for each component separately, it is possible to identify which sizes of the main grain are the most different in comparison with those of the impurities. (Conclusions) We obtained a formula for evaluating the technological effect of separation by the example of separation of seed mixtures in the ascending air flow of pneumatic sorting machines, characterized in that it takes into account the soaring speed of the separated components as a sign of separation.

Generalized Second Einstein Relation in Heterogeneous Media and Population Growth Models

Generalized second Einstein relation is obtained from a Fokker–Planck equation for a wide class of space-dependent coefficients. The relation is investigated for population growth models.

Analisis Penerapan Deret Ukur dalam Perhitungan Laju Pertumbuhan Penduduk Terhadap Tingkat Kemiskinan

This study aims to analyze the application of a series of measures in calculating the rate of population growth to the poverty rate. The measuring series in the economy is a model of population growth. Population growth is a change in the number of inhabitants in a population that occurs over a certain period. Judging from data from BPS (Central Statistics Agency) regarding the population growth rate in 2015-2022, there are similar differences. BPS also stated that Indonesia's population growth rate in 2020-2025 was 0.9%. In research conducted using the literature study method which is one type of qualitative research which uses references derived from books, scientific articles such as journals, proceedings that are in accordance with the topic to be discussed. The purpose of applying the measuring series in the calculation of the population growth rate to the poverty rate is to predict the number of inhabitants in 2023-2025 and its effect on the poverty rate. An increasing population will result in a large gap between the population, low quality and ability of the population, causing an increase in the level of poverty.

Analisis Penerapan Deret Ukur dalam Perhitungan Laju Pertumbuhan Penduduk Terhadap Tingkat Kemiskinan

This study aims to analyze the application of a series of measures in calculating the rate of population growth to the poverty rate. The measuring series in the economy is a model of population growth. Population growth is a change in the number of inhabitants in a population that occurs over a certain period. Judging from data from BPS (Central Statistics Agency) regarding the population growth rate in 2015-2022, there are similar differences. BPS also stated that Indonesia's population growth rate in 2020-2025 was 0.9%. In research conducted using the literature study method which is one type of qualitative research which uses references derived from books, scientific articles such as journals, proceedings that are in accordance with the topic to be discussed. The purpose of applying the measuring series in the calculation of the population growth rate to the poverty rate is to predict the number of inhabitants in 2023-2025 and its effect on the poverty rate. An increasing population will result in a large gap between the population, low quality and ability of the population, causing an increase in the level of poverty.

Analyzing population dynamics models via Sumudu transform

This study demonstrates how to construct the solutions of a more general form of population dynamics models via a blend of variational iterative method with Sumudu transform. Evolution of population growth models are presented and new models which are more general, are proposed in form of delay differential equations of pantograph type. This study presents suitable reformulation and reconstruction for some existing population growth models in terms of delay differential equations of pantograph type. Also, presentation is given on innovative ways to obtain the solutions of population growth models where other analytic methods fail. Stimulating procedures for finding patterns and regularities in seemingly chaotic processes are elucidated in this paper. Some single and interacting species population models are illustrated graphically and analyzed. How, when and why the changes in population sizes occur can be deduced through this study.

Analysis of the population growth model to maintain environmental stability in the Province of The Bangka Belitung Islands

The province of the Bangka Belitung archipelago is one of the relatively young provinces in Indonesia. Based on BPS data in 2021, the population of Bangka Belitung is around 1.473.165. This population data is very useful for formal demography and will influence local government policies, economic stability and environmental balance. In this study, the population growth of the Bangka Belitung Islands Province was modeled using the Leslie model. The model show that the population of the Bangka Belitung Islands Province will decrease slowly.

PROYEKSI PERTUMBUHAN PENDUDUK KABUPATEN PEGUNUNGAN ARFAK MENGGUNAKAN MODEL LOGISTIK

Arfak Mountains Regency is an expansion area of Manokwari Regency which was formed based on the law of the Republic of Indonesia Number 24 of 2012 concerning the expansion of Arfak Mountain Regency in West Papua Province. The population growth of the Arfak Mountains Regency which has increased after the expansion can cause social problem in the area. social problems arising from the increase in population can be anticipated by using population growth projection. The purpose of this paper is to determine the logistic model and project population growth in the Arfak Mountains Regency. The results of this study are the mathematical model of population growth in the Arfak Mountains Regency using the logistic model is:
 
 The projected population growth of Arfak Mountains Regency in 2030 is people with an intrinsic growth rate of which is .

Stochastic differential equation models for tumor population growth

In this paper we develop stochastic differential equation models for tumor population growth with immunization. We investigate especially the effect of a multiplicative noise on the progression of tumor evolution. Then, we perform a computational analysis in order to assess the behavior of the solution process. With this, we analyze the population extinction probability and the probability of persistence. In the case of persistence we analyze the behavior of the steady probability density and the evolution of its mean and variance. We further calculate the mean first passage time in order to describe the probability transitions between the extinction state and the state of the stable tumor. It is found that an increasing noise intensity rate enhances the probability of the extinction of the tumor.

Planning gaps: unexpected urban expansion in five Colombian metropolitan areas

Colombia has experienced rapid urbanization over the past three decades. Most Colombian cities doubled their urban extent in the last 10 years which resulted in a high demand for land. This research identifies urban expansion patterns in five of the largest urban agglomerations in Colombia. Urban growth is analysed using satellite images (Landsat 5) and census data to assess spatiotemporal land-use changes over a 30-year period (1990–2020). The actual urban extents are compared with each city’s land-use predictions, instruments, and regulations to ascertain whether local authorities have the capabilities to predict land demand and to guide development processes at the municipal level. The predictions made by local authorities are inaccurate and often underestimate the rates of population growth and land requirements. The findings reveal that local authorities lack the capabilities to manage urban growth and deliver sustainable urban development. This is leading to poor outcomes: low planning standards, urban informality and inefficient land use. <em><strong>Policy relevance</strong></em> This research reveals a significant gap between urban land-use policy instruments and actual urban growth patterns in Colombian cities. The findings reveal that the current urban expansion surpassed what local authorities had anticipated and allocated for land use. Although existing policies empower local authorities, their capabilities to effectively monitor and model population growth and associated land requirements are poor. This led to an underestimation of land requirements and poor planning outcomes. To improve future decision-making and management of urban growth, urban planners should use empirical data to inform urban growth scenarios: allocate sufficient land to allow for orderly growth, designate specific areas for development and provide for sufficient infrastructure.

Life cycle and population dynamics of Bursaphelenchus willibaldi (Nematoda: Rhabditida: Aphelenchoididae) in vitro

Summary To develop models of forest ecosystem functioning, it is necessary to estimate parameters of the population dynamics of nematode species. Parameters of ontogenesis of Bursaphelenchus willibaldi from oak in culture of the fungus Botrytis cinerea were determined in vitro: oviposition began 2.7 (1-3) days after inoculation with adult nematodes; timelines of juvenile formation were: second-stage juveniles: 3.2 (3-4) days, third-stage juveniles: 3.6 (3-5) days, fourth-stage juveniles: 4.8 (3-6) days, first generation (1G) ended with a J4 moulting to adult after 5.8 (4-6) days. One day after the formation of the first generation, nematodes left the 2% potato-sugar agar (PSA) medium with the feed fungus and moved upwards, forming a migratory group (MG). In PSA the total nematode abundance reached peaks on day 11 (2G) and in the MG on day 27 (4.5G). The fecundity of females during population growth was determined as 3.4 (2.1-5.9) eggs day−1 and a model of exponential population growth was developed for total nematodes , ; and for females , . Under conditions of unrestricted reproduction and temperature of 21-23°C, the nematode and fungus can colonise 1 m3 of PSA-like medium in 36.8 days. The survival stage in the propagative generation was presumably J4. The female lifespan consists of a feeding and reproductive phase in the PSA (6 days) and a survival phase in the MG (1 month to 1 year). In MG, nematodes formed swarming groups of 20-200 individuals.

Locked fronts in a discrete time discrete space population model.

A model of population growth and dispersal is considered where the spatial habitat is a lattice and reproduction occurs generationally. The resulting discrete dynamical system exhibits velocity locking, where rational speed invasion fronts are observed to persist as parameters are varied. In this article, we construct locked fronts for a particular piecewise linear reproduction function. These fronts are shown to be linear combinations of exponentially decaying solutions to the linear system near the unstable state. Based upon these front solutions, we then derive expressions for the boundary of locking regions in parameter space. We obtain leading order expansions for the locking regions in the limit as the migration parameter tends to zero. Strict spectral stability in exponentially weighted spaces is also established.

Daubechies Wavelet Scaling Function Approach to Solve Volterra’s Population Model

In this paper, we focus on a collocation approach based on Daubechies wavelet scaling functions for approximating the solution of Volterra’s model of population growth of a species with a closed system. We present that the integral and derivative terms, which appear in Volterra’s model of the population, will be computed exactly in dyadic points. Utilizing this collocation technique, Volterra’s population model reduces into a system of nonlinear algebraic equations. In addition, an error bound for our method will be explored. The numerical results demonstrate the applicability and accuracy of our method.

Machine learning for population growth modeling through annual CO2 data

This article presents a general framework to model the population growth of Colombia through machine learning, which allows incorporating variables such as CO2 emissions. The data are obtained through the DANE Geoportal and the World Bank portal database. In recent years, several cities in Colombia have experienced an accelerated population and urban growth as a result of an overwhelming increase in the immigrant population, a situation that has been affecting the urban order of the city, mainly due to population confinement, increased environmental pollution, unhealthiness, poverty among other factors.The population growth prediction fully shows the effects of the fertility rate, mortality, and migration of people from one territory to another, essential factors in determining population and health system conditions. Accurate information can be obtained from population census measurements, a strategy with a high cost; However, the capabilities of machine learning are growing, being also implemented to determine predictions of systems and behaviors in demographic, environmental, and socioeconomic issues, which contributes to the economic and energy-saving that implies the gathering and processing of demographic information for the country.In this work, to predict population growth, the concept of machine learning was applied, carrying out a data analysis using an Artificial Neural Network (ANN). The results obtained provide a predictive model with the potential to provide regional and governmental entities with suggestions, strategies, and alternatives for studying the population and making decisions for urban redevelopment.

Investigating the Ability of Growth Models to Predict In Situ Vibrio spp. Abundances.

Vibrio spp. have an important role in biogeochemical cycles; some species are disease agents for aquatic animals and/or humans. Predicting population dynamics of Vibrio spp. in natural environments is crucial to predicting how the future conditions will affect the dynamics of these bacteria. The majority of existing Vibrio spp. population growth models were developed in controlled environments, and their applicability to natural environments is unknown. We collected all available functional models from the literature, and distilled them into 28 variants using unified nomenclature. Next, we assessed their ability to predict Vibrio spp. abundance using two new and five already published longitudinal datasets on Vibrio abundance in four different habitat types. Results demonstrate that, while the models were able to predict Vibrio spp. abundance to an extent, the predictions were not reliable. Models often underperformed, especially in environments under significant anthropogenic influence such as aquaculture and urban coastal habitats. We discuss implications and limitations of our analysis, and suggest research priorities; in particular, we advocate for measuring and modeling organic matter.

Mathematical Models for Population Growth with Variable Carrying Capacity: Analytical Solutions

A general population model with variable carrying capacity consisting of a coupled system of nonlinear ordinary differential equations is proposed, and a procedure for obtaining analytical solutions for three broad classes of models is provided. A particular case is when the population and carrying capacity per capita growth rates are proportional. As an example, a generalised Thornley–France model is given. Further examples are given when the growth rates are not proportional. A criterion when inflexion may occur is also provided, and results of numerical simulations are presented.

Birth and death processes in interactive random environments

This paper studies birth and death processes in interactive random environments where the birth and death rates and the dynamics of the state of the environment are dependent on each other. Two models of a random environment are considered: a continuous-time Markov chain (finite or countably infinite) and a reflected (jump) diffusion process. The background is determined by a joint Markov process carrying a specific interactive mechanism, with an explicit invariant measure whose structure is similar to a product form. We discuss a number of queueing and population-growth models and establish conditions under which the above-mentioned invariant measure can be derived. Next, an analysis of the rate of convergence to stationarity is performed for the models under consideration. We consider two settings leading to either an exponential or a polynomial convergence rate. In both cases we assume that the underlying environmental Markov process has an exponential rate of convergence, but the convergence rate of the joint Markov process is determined by certain conditions on the birth and death rates. To prove these results a coupling method turns out to be useful.