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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
301

An application of the Tracking-Trapping technique in estimating population density.

O'Neil, J. Kevin January 1976 (has links)
No description available.
302

Analysis of Inbreeding in a Closed Population of Crossbred Sheep

MacKinnon, Kathryn Michelle 05 September 2003 (has links)
Genetic diversity and the effect of lamb and dam inbreeding on multiple traits were analyzed in an 11-yr closed population of sheep established in 1983 and remained closed after 1987, with 50% Dorset, 25% Rambouillet, and 25% Finnsheep breeding to determine selection response for spring fertility. The population had been randomly divided in 1987 into a fall-lambing selection line (S) of 125 ewes and 10 rams, fall-lambing environmental control line (E) of 55 ewes and 5 rams, and a spring-lambing genetic control line (G) of 45 ewes and 5 rams. Inbreeding effects were estimated from 2678 lambs and 556 dams present after the creation of the respective lines. The traits assessed were ewe spring-fertility, lambing date, lamb birth, 60 d, and 120 d weight, and lamb survival to 1, 3, and 14 d. Genetic diversity was assessed by estimating change in inbreeding per generation (ΔF) and effective number of breeding animals (N<sub>e</sub>), and parameters derived from gene drop simulations and an iterative procedure developed by Boichard et al. (1997); effective number of founders (f<sub>e</sub>), effective number of ancestors (f<sub>a</sub>), founder genome equivalents (f<sub>g</sub>), and two additional measures of genetic diversity (GD₁, GD2). In order to estimate the diversity available in S and G, three sets of animals from the end of the study and one set of animals at line formation were considered in each line: all lambs born (including dead lambs), all matings (including potential offspring, even if a lamb was not born), and all rams and ewes available at the end of the study and at line formation. At the time of line formation, most of the loss in diversity was due to unequal founder representation. The smaller population of G, as compared to S, caused a greater decrease in diversity due to bottlenecks at line formation. Very little diversity was lost due to additional drift by the time of line formation because selection had not occurred and a random mixing of founders was the goal. Allelic diversity decreased moderately; of the 322 founder alleles, there were 71% in S and 58% in G of rams and ewes (RE) that appeared in at least 50 runs of gene drop. By the end of the study in 1998, the amount of allelic diversity had decreased substantially. Of the alleles possible in RE at the end of the study in S and G, only 6 and 8 %, respectively, appeared in greater than 50 simulations of gene drop. The measures of f<sub>e</sub>, f<sub>a</sub>, and f<sub>g</sub> revealed there was not much additional loss in diversity from the line founders to the end of the study due to unequal founder representation, but there was a larger amount of loss due to bottlenecks and additional drift. The diversity loss was similar, which was the goal of the selection study, when values for RE were compared in S and G. The effects of lamb and dam inbreeding were estimated from REML analysis. Effects of lamb or dam inbreeding were negative but not significant for lambing date or survival to 1, 3, or 14 d. Spring fertility was estimated to decrease by 0.70 ± 0.30 %/% inbreeding of the ewe (P < 0.01), which seems even greater since the average spring fertility was only 47.5 %. Effects of lamb inbreeding on birth, 60-d, and 120-d weights were -0.012 ± 0.006 (P < 0.05), -0.045 ± 0.020 (P < 0.05), and -0.130 ± 0.034 kg/% (P < 0.01), respectively. Dam inbreeding had smaller effects on birth, 60-d, and 120-d weights of -0.008 ± 0.010 (ns), -.033 ± 0.034 (ns), and -0.087 ± 0.056 (P < 0.1) kg/%, respectively. / Master of Science
303

Conservation and ecology of the hazel dormouse, Muscardinus avellanarius

Mills, Cheryl Anne January 2012 (has links)
Conservation biologists require information on the distribution, ecology, behaviour and genetic diversity of endangered species in order to identify threatened populations, determine which mechanisms are driving populations closer to extinction, and design appropriate mitigating solutions. The hazel dormouse, Muscardinus avellanarius, is declining across much of its northern range. Dormice are detrimentally affected by habitat degradation, loss and fragmentation. Despite extensive studies and conservation work on hazel dormice, there remain many gaps in our understanding. This thesis aims to fill some of those gaps. Hazel dormice are elusive, and therefore difficult to monitor in the wild. I demonstrate the utility of novel monitoring techniques for the rapid determination of dormouse presence, and provide algorithms for the objective verification of species identity from small mammal footprints. I design and utilise genetic microsatellite markers to investigate molecular ecology in this species. In one of the first studies of hazel dormouse population genetics, I describe high levels of population differentiation and genetic isolation across the southwest UK range. I find a powerful signal of reduction in genetic diversity, and an increase in differentiation between core and peripheral populations. I consider rival hypotheses for the mechanisms driving this population genetic pattern, and place the results in the context of conservation strategies for UK dormice. Further, I use molecular data to investigate the prevalence of multiple paternity in wild dormouse populations. Results contradict a recent estimate of very high rates of polyandry, but remain high at 50%. I investigate the effect of food availability on the hibernation behaviour of dormice. My findings, which demonstrate dormice are variable and flexible in their response to winter diet, increases our understanding of the trade-offs dormice must make in order to survive winter periods. I hope that the research undertaken for this thesis will add to the understanding and conservation of an iconic British mammal, ultimately contributing to the persistence of this species.
304

Land use and population regulation : vole dynamics in a grazing experiment

Fernandez de la Pradilla Villar, Jose Ignacio January 2009 (has links)
Land use is the major global driver of biodiversity loss and ecosystem change. In this thesis the impact of an important land use practice, livestock grazing, in the population dynamics of a keystone species of temperate grassland ecosystems, the field vole Microtus agrestis, was investigated in a manipulative grazing experiment in the UK uplands. Vole densities at different spatial scales declined with increasing grazing intensities. This decline was especially acute and non-linear at high altitudes, where the preferred habitat of voles is less abundant. The activity of an important vole predator, the red fox Vulpes vulpes, declined accordingly. The evidence suggested that the availability of voles to foxes changed between grazing treatments. A behavioural response to reduced habitat quality was the most likely mechanism to explain vole declines with grazing, while food limitation or increased predation received no support as valid mechanisms to explain vole declines. Grazing increased vole mobility, changed sex-specific patterns of natal dispersal, affected the age structure of the female population and led to biases in sex ratios amongst the adult population. Despite profound demographic changes, the dynamics of the vole population was unaffected by grazing. Neither direct nor delayed density dependent dynamics nor seasonal dynamics changed between grazing treatments. Apparent survival in adults was not direct density dependent and similar in ungrazed and grazed areas. Negative direct density dependence in reproductive and immigration rates, and population growth rates at different spatial scales was strong and did not change in response to grazing. Thus, livestock grazing reduced vole densities probably through a behavioural response to grazing, but it did not affect the demographic mechanisms of population regulation or vole population dynamics.
305

Selected Demographic and Socioeconomic Factors Related to Urbanization in Iran, 1956-1966

Hashemi, Alireza Shapur 08 1900 (has links)
Demographic and Socioeconomic factors related to the urbanization of Iran are discussed. An historical review of the growth of urbanization in Iran is reported. Factors included in the analysis are the birth, death, literacy, and mobility rates as well as the age-sex structure of the population. The data are from the national censuses of 1956 and 1966. Changes in demographic trends in both major and smaller cities during this decade are discussed in detail. The results of the analyses of these data are applicable to most developing countries. This information may be of possible aid in planning for the growth and redistribution of the Iranian population.
306

Galactic archaeology with metal-poor stars

Nordlander, Thomas January 2017 (has links)
The chemical fingerprints of old, metal-poor stars can be used to unravel the events of the newborn Universe and help us understand the properties of the first stars and star clusters. The study of nearby stars to infer properties in the distant past is often referred to as Galactic archaeology. However, the chemical composition of stars cannot be observed directly, but must be inferred by means of spectroscopic modelling. Traditionally, this modelling utilises one-dimensional (1D) stellar atmospheres in hydrostatic and local thermodynamic equilibrium (LTE). Today, we know that departures from LTE (known as NLTE), and differences between 1D model atmospheres and their hydrodynamical three-dimensional (3D) counterparts, become increasingly severe at lower metallicity. The development of NLTE modelling of spectral line formation in 3D atmospheres is still in its infancy, but constitutes a remarkable step forward that has been made possible by parallelised codes and supercomputers. The central theme of this thesis is the application of NLTE analyses to metal-poor stars, to help usher the field of Galactic archaeology forward with important consequences for the nature of the first stellar generations. I present a theoretical NLTE study of aluminium, where I validate the analysis using a set of bright standard stars and provide calculated NLTE effects for a large parameter space. I perform 3D NLTE calculations for the solar spectrum to better constrain the zero-point of the cosmic abundance scale, and find excellent agreement with the meteoritic aluminium abundance. I also present NLTE analyses of metal-poor stars in the globular clusters NGC 6397 and M4. While globular cluster stars were long expected to form from a chemically homogeneous medium, star-to-star abundance variations of light elements indicate multiple epochs of star formation. Massive first-generation stars polluted the interstellar medium from which later generations formed, and I use the observed abundance variations to deduce the properties of the polluting stars. Among the heavier elements, I uncover evolutionary abundance variations that match predictions of stellar evolution models with atomic diffusion. The results indicate that the chemical abundance ratios of unevolved metal-poor stars are affected by gravitational settling, with a bias of the order 25-50 %, increasing towards lower metallicity. This atmospheric depletion mechanism is a probable explanation to why the stellar abundances of lithium fall short of the predictions from standard Big Bang nucleosynthesis. Finally, I apply a 3D NLTE abundance analysis to the red giant SMSS 0313-6708, which is the most iron-deficient star known. The chemical abundance pattern of this star indicates that it formed from gas affected only by Big Bang nucleosynthesis and a single faint supernova. Comparison of the inferred abundance pattern to theoretical predictions leads to constraints on the explosion mechanism and the mass of the metal-free progenitor star.
307

Host Densities and Parasitism Rates in a Forest Defoliator Across a Rural-Urban Landscape

Nelson, Abigail J 01 January 2016 (has links)
Fall cankerworm (FCW) outbreaks have recently increased in frequency and intensity in the mid-Atlantic region of the United States, especially around cities of Charlotte, NC and Richmond, VA. This study evaluated the effects of two landscape features associated with urbanization, impervious surface and forest cover, on population patterns of FCW and its parasitoids across eastern Virginia. Forest cover was positively related to parasitism rates while impervious surface was positively related to FCW abundance, suggesting that FCW outbreaks may be amplified in urban areas. FCW abundance declined over the two-year period of this study, but parasitism rate increased at most sites. Parasitism was highest at sites that experienced FCW outbreaks first, indicating that parasitoid populations are responding to moth abundances. It remains to be seen whether this outbreak was an aberrant occurrence, or represents a regime shift to more frequent defoliation in Virginia, similar to that in North Carolina urban areas.
308

Analyse statistique de la diversité en anthropometrie tridimensionnelle / Statistical analysis of diversity in three-dimensional anthropometry

Kollia, Aikaterini 13 January 2016 (has links)
L’anthropométrie est le domaine scientifique qui étudie les dimensions du corps humain. La complexité de la morphologie du corps nécessite une analyse 3D, aujourd’hui permise par les progrès des scanners 3D. L’objectif de cette étude est de comparer les populations et utiliser les résultats pour mieux adapter les produits sportifs à la morphologie des utilisateurs. Des campagnes de mensuration 3D ont été réalisées et des algorithmes de traitement automatique ont été créés pour analyser les nuages de points des sujets scannés. Basés sur les méthodes d’images et de géométrie, ces algorithmes repèrent des points anatomiques, calculent des mesures 1D, alignent les sujets scannés et créent des modèles anthropométriques 3D représentatifs des populations. Pour analyser les caractéristiques anthropométriques, des statistiques de premier ordre et factorielles ont été adaptées pour être utilisées dans l’espace 3D. Les méthodes ont été appliquées à trois parties : le pied, la tête et la poitrine. Les différences morphologiques entre les populations, mais également au sein d’une population donnée, ont été révélées. Par exemple, la différence à chaque point de la tête entre des têtes a été calculée. Les statistiques en trois dimensions ont aussi permis de mettre en évidence l’asymétrie de la tête. La méthode de création de modèles anthropométriques est plus adaptée à nos applications que les méthodes dans la littérature. L’analyse en trois dimensions permet d’obtenir des résultats qui ne sont pas visibles par les analyses 1D. Les connaissances acquises par cette étude sont utilisées pour la conception de différents produits vendus dans les magasins DECATHLON à travers le monde. / Anthropometry is the scientific field that studies human body dimensions (from the greek άνθρωπος (human) + μέτρον (measure)). Anthropometrical analysis is based actually on 1D measurements (head circumference, length, etc). However, the body’s morphological complexity requires 3D analysis. This is possible due to recent progress of 3D scanners. The objective of this study is to compare population’s anthropometry and use results to adapt sporting goods to user’s morphology. For this purpose, 3D worldwide measurement campaigns were realized and automated treatment algorithms were created in order to analyze the subjects’ point cloud. Based on image processing methods and on shape geometry, these algorithms detect anatomical landmarks, calculate 1D measurements, align subjects and create representative anthropometrical 3D models. In order to analyze morphological characteristics, different statistical methods including components’ analysis, were adapted for use in 3D space. The methods were applied in three body parts: the foot, the head and the bust. The morphological differences between and inside the populations were studied. For example, the difference in each point of the head, between Chinese and European head, was calculated. The statistics in three dimensions, permitted also to show the asymmetry of the head. The method to create anthropometrical models is more adapted to our applications than the methods used in the literature. The analysis in three dimensions, can give results that they are not visible from 1D analyses. The knowledge of this thesis is used for the conception of different products that they are sold in DECATHLON stores around the world.
309

Factors affecting the optimisation of diagnostic radiation exposures of the population in Hong Kong.

January 1993 (has links)
Chan Mok-wah, Paul. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1993. / Includes bibliographical references (leaves [219-231]). / ACKNOWLEDGEMENTS / SUMMARY / LIST OF ABBREVIATIONS / Chapter CHAPTER 1. --- INTRODUCTION / Chapter 1.1 --- HISTORY --- p.1 / Chapter 1.2 --- RADIATION EXPOSURES OF THE POPULATION --- p.1 / Chapter 1.2.1 --- Introduction --- p.1 / Chapter 1.2.1 --- The Projected Expansion of Medical Exposures --- p.2 / Chapter 1.3 --- RADIATION HAZARDS --- p.6 / Chapter 1.3.1 --- Deterministic Effects --- p.6 / Chapter 1.3.2 --- Stochastic Effects --- p.7 / Chapter 1.3.3 --- Pre-natal Irradiation --- p.9 / Chapter 1.4 --- THE LOCAL SITUATION --- p.9 / Chapter 1.5 --- JUSTIFICATION OF THE STUDY OF LOCAL PATIENT DOSE --- p.10 / Chapter CHAPTER 2. --- THE MEDICAL EXPOSURES IN HONG KONG / Chapter 2.1 --- INTRODUCTION --- p.11 / Chapter 2.2 --- MAN-MADE RADIATION IN HONG KONG --- p.11 / Chapter 2.2.1 --- Occupational Exposure --- p.11 / Chapter 2.2.2 --- Radioactive Fall-out --- p.12 / Chapter 2.2.3 --- Nuclear Medicine --- p.12 / Chapter 2.2.4 --- Diagnostic Radiology --- p.12 / Chapter 2.3 --- THE FUTURE TREND --- p.13 / Chapter 2.4 --- THE CURRENT STUDY --- p.15 / Chapter CHAPTER 3. --- METHODS OF OPTIMISATION / Chapter 3.1 --- INTRODUCTION --- p.17 / Chapter 3.2 --- JUSTIFICATION OF DIAGNOSTIC RADIATION EXPOSURE --- p.17 / Chapter 3.3 --- OPTIMISATION OF DIAGNOSTIC RADIATION EXPOSURE --- p.18 / Chapter 3.4 --- THE CONTROL OF EXPOSURES --- p.19 / Chapter 3.4.1 --- The Control of Occupational Exposure --- p.19 / Chapter 3.4.2 --- The Control of Public Exposure --- p.20 / Chapter 3.4.3 --- The Control of Patient Exposure --- p.20 / Chapter 3.5 --- A PRACTICAL APPROACH TO CONTROL PATIENT EXPOSURES --- p.23 / Chapter 3.5.1 --- Intrumental Approach --- p.23 / Chapter 3.5.2 --- Technical Approach --- p.24 / Chapter 3.5.3 --- Administrative Approach --- p.25 / Chapter 3.6 --- CONCLUSION --- p.26 / Chapter CHAPTER 4. --- METHOD OF STUDY / Chapter 4.1 --- INTRODUCTION --- p.27 / Chapter 4.2 --- A WORKING SCHEME --- p.27 / Chapter 4.3 --- THE MEASUREMENT OF ESD --- p.29 / Chapter 4.3.1 --- Thermoluminescent Dosimetry --- p.29 / Chapter 4.3.2 --- The TL Material Adopted --- p.30 / Chapter 4.3.3 --- Irradiated of TLDs --- p.32 / Chapter 4.3.4 --- Readout of the Exposed TLDs --- p.32 / Chapter 4.3.5 --- Accuracy of Readings --- p.35 / Chapter 4.4 --- MONTE CARLO SIMULATION --- p.36 / Chapter 4.4.1 --- Introduction --- p.36 / Chapter 4.4.2 --- History --- p.38 / Chapter 4.4.3 --- The Principle --- p.38 / Chapter 4.4.4 --- Photon History --- p.40 / Chapter 4.4.5 --- The Use of Monte Carlo simulation in Organ Doses Estimation --- p.47 / Chapter 4.4.6 --- The Electron-Gamma-Shower (EGS4) Code System --- p.51 / Chapter 4.5 --- A LOCAL MATHEMATICAL PHANTOM --- p.52 / Chapter 4.5.1 --- Introduction --- p.52 / Chapter 4.5.2 --- An Ideal Mathematical Phantom --- p.52 / Chapter 4.5.3 --- Choice of Mathematical Phantom Model --- p.53 / Chapter 4.5.4 --- The Development of a Chinese Mathematical Phantom --- p.55 / Chapter 4.5.5 --- Results --- p.56 / Chapter 4.5.6 --- A Comparison --- p.60 / Chapter 4.6 --- A SUMMARY --- p.62 / Chapter CHAPTER 5. --- POPULATION STUDIES / Chapter 5.1 --- INTRODUCTION --- p.63 / Chapter 5.2 --- FREQUENCY SURVEY --- p.63 / Chapter 5.2.1 --- Survey in Private Sectors --- p.63 / Chapter 5.2.2 --- Surveyin Government Sectors --- p.64 / Chapter 5.3 --- DOSE SURVEY --- p.66 / Chapter 5.3.1 --- Selection of Regions and Projections --- p.66 / Chapter 5.3.2 --- Selection of Hospitals and Laboratories --- p.66 / Chapter 5.4 --- SAMPLE SIZE --- p.67 / Chapter CHAPTER 6. --- RESULTS / Chapter 6.1 --- INTRODUCTION --- p.68 / Chapter 6.2 --- SAMPLE SIZE --- p.68 / Chapter 6.3 --- AGE BAND AND SEX DISTRIBUTION --- p.68 / Chapter 6.4 --- THE MEASURED ESD --- p.75 / Chapter 6.4.1 --- Histograms of ESDs by Projection --- p.75 / Chapter 6.4.2 --- A Comparison of ESDs by Projection --- p.89 / Chapter 6.4.3 --- A Comparison of ESDs by Centre --- p.93 / Chapter 6.4.4 --- A Comparison of Collective ESDs by Centre --- p.96 / Chapter 6.5 --- THE ESTIMATED ORGAN DOSES --- p.103 / Chapter 6.5.1 --- Introduction --- p.103 / Chapter 6.5.2 --- Method --- p.103 / Chapter 6.5.3 --- Normalised Organ Doses --- p.105 / Chapter 6.5.4 --- Organ doses per Projection --- p.105 / Chapter 6.5.5 --- A Computerised programme --- p.119 / Chapter 6.6 --- A COMPARISON OF ORGAN DOSES ESTIMATED ON LOCAL AND NRPB MODELS --- p.152 / Chapter CHAPTER 7. --- SOURCES OF UNCERTAINTY / Chapter 7.1 --- UNCERTAINTITIES IN COMPUTATION --- p.156 / Chapter 7.1.1 --- Inaccuracy of the Justaposition of Complex Human Anatomy and the X-ray Beam --- p.156 / Chapter 7.1.2 --- Statistical Uncertainties --- p.156 / Chapter 7.1.3 --- Attenuation Coefficient Uncertainties --- p.157 / Chapter 7.1.4 --- Anatomic Inexactitudes --- p.157 / Chapter 7.2 --- ERRORS CONTRIBUTED BY TLDs --- p.155 / Chapter 7.3 --- TOTAL POSSIBLE ERROR --- p.157 / Chapter 7.4 --- VERIFICATION OF THE RESULTS --- p.158 / Chapter 7.4.1 --- Verification of the Measured ESD --- p.158 / Chapter 7.4.2 --- Verification of the Estimated Organ Doses --- p.158 / Chapter CHAPTER 8. --- HEALTH IMPLICATIONS / Chapter 8.1 --- INTRODUCTION --- p.161 / Chapter 8.2 --- DATA SOURCE --- p.161 / Chapter 8.3 --- ASSUMPTIONS --- p.162 / Chapter 8.4 --- SOMATIC RISK --- p.162 / Chapter 8.4.1 --- Somatically Significant Dose (SSD) --- p.162 / Chapter 8.4.2 --- Results --- p.163 / Chapter 8.5 --- LEUKAEMIC RISK --- p.166 / Chapter 8.5.1 --- Leukaemically Significant Dose (LSD) --- p.166 / Chapter 8.5.2 --- Results --- p.167 / Chapter 8.6 --- GENETIC RISK --- p.170 / Chapter 8.6.1 --- Genetically Significant Dose (GSD) --- p.170 / Chapter 8.6.2 --- Results --- p.171 / Chapter 8.7 --- DISCUSSION --- p.174 / Chapter CHAPTER 9. --- DISCUSSION --- p.199 / Chapter 9.1 --- MEAN ESDs PER PROJECTION --- p.199 / Chapter 9.2 --- A COMPARISON OF MEAN ESDs BETWEEN LOCAL CENTRES --- p.200 / Chapter 9.3 --- A COMPARISON OF MEAN ESDs BETWEEN COUNTRIES --- p.202 / Chapter 9.4 --- EFFECTIVE DOSE PER EXAMINATION --- p.203 / Chapter 9.5 --- NEED FOR LOCAL ANTHROPOMORPHIC PHANTOM --- p.204 / Chapter 9.6 --- ORGAN DOSES WITH HIGH CANCER INDUCTION --- p.205 / Chapter 9.7 --- A DISTRIBUTION OF COLLECTIVE DOSES --- p.206 / Chapter 9.8 --- "A DISTRIBUTION OF SSD, LSD AND GSD" --- p.209 / Chapter 9.9 --- OVERALL RISK ESTIMATION --- p.212 / Chapter 9.10 --- POPULATION ORGAN DOSES --- p.213 / Chapter 9.11 --- SUMMARY --- p.214 / Chapter CHAPTER 10. --- CONCLUSION --- p.217 / REFERENCES --- p.R 1 - 12 / APPENDICES / Chapter A. --- RADIATION QUANTITIES USED IN PATIENT DOSIMETRY --- p.A 1 - 12 / Chapter B. --- QUALITY ASSURANCE --- p.B 1 - 14 / Chapter C. --- DOSE REDUCTION --- p.C 1 - 11 / Chapter D. --- REJECT ANALYSIS --- p.D 1 - 15 / Chapter E. --- PUBLISHED WORK IN DOSE MEASUREMENT --- p.E 1 - 18 / Chapter F. --- THERMOLUMINESCENT DOSIMETRY --- p.F 1 - 27 / Chapter G. --- A STUDY ON ANTHROPOMORPHIC PHANTOM --- p.G 1 - 4
310

Equations of structured population dynamics.

January 1990 (has links)
Guo Bao Zhu. / Thesis (Ph.D.)--Chinese University of Hong Kong. / Includes bibliographical references. / Abstract --- p.1 / Introduction --- p.3 / Chapter Chapter 1. --- Semigroup for Age-Dependent Population Equations with Time Delay / Chapter 1.1 --- Introduction --- p.13 / Chapter 1.2 --- Problem Statement and Linear Theory --- p.14 / Chapter 1.3 --- Spectral Properties of the Infinitesimal Generator --- p.20 / Chapter 1.4 --- A Nonlinear Semigroup of the Logistic Age-Dependent Model with Delay --- p.26 / References --- p.34 / Chapter Chapter 2. --- Global Behaviour of Logistic Model of Age-Dependent Population Growth / Chapter 2.1 --- Introduction --- p.35 / Chapter 2.2 --- Global Behaviour of the Solutions --- p.37 / Chapter 2.3 --- Oscillatory Properties --- p.47 / References --- p.51 / Chapter Chapter 3. --- Semigroups for Age-Size Dependent Population Equations with Spatial Diffusion / Chapter 3. 1 --- Introduction --- p.52 / Chapter 3.2 --- Properties of the Infinitesimal Generator --- p.54 / Chapter 3.3 --- Properties of the Semigroup --- p.59 / Chapter 3.4 --- Dynamics with Age-Size Structures --- p.61 / Chapter 3.5 --- Logistic Model with Diffusion --- p.66 / References --- p.70 / Chapter Chapter 4. --- Semi-Discrete Population Equations with Time Delay / Chapter 4. 1 --- Introduction --- p.72 / Chapter 4.2 --- Linear Semi-Discrete Model with Time Delay --- p.74 / Chapter 4.3 --- Nonlinear Semi-Discrete Model with Time Delay --- p.88 / References --- p.98 / Chapter Chapter 5. --- A Finite Difference Scheme for the Equations of Population Dynamics / Chapter 5.1 --- Introduction --- p.99 / Chapter 5.2 --- The Discrete System --- p.102 / Chapter 5.3 --- The Main Results --- p.107 / Chapter 5.4 --- A Finite Difference Scheme for Logistic Population Model --- p.113 / Chapter 5.5 --- Numerical Simulation --- p.116 / References --- p.119 / Chapter Chapter 6. --- Optimal Birth Control Policies I / Chapter 6. 1 --- Introduction --- p.120 / Chapter 6.2 --- Fixed Horizon and Free Point Problem --- p.120 / Chapter 6.3 --- Time Optimal Control Problem --- p.129 / Chapter 6.4 --- Infinite Horizon Problem --- p.130 / Chapter 6.5 --- Results of the Nonlinear System with Logistic Term --- p.143 / Reference --- p.148 / Chapter Chapter 7. --- Optimal Birth Control Policies II / Chapter 7. 1 --- Free Final Time Problems --- p.149 / Chapter 7.2 --- Systems with Phase Constraints --- p.160 / Chapter 7.3 --- Mini-Max Problems --- p.166 / References --- p.168 / Chapter Chapter 8. --- Perato Optimal Birth Control Policies / Chapter 8.1 --- Introduction --- p.169 / Chapter 8.2 --- The Duboviskii-Mi1yutin Theorem --- p.171 / Chapter 8.3 --- Week Pareto Minimum Principle --- p.172 / Chapter 8.4 --- Problem with Nonsmooth Criteria --- p.175 / References --- p.181 / Chapter Chapter 9. --- Overtaking Optimal Control Problems with Infinite Horizon / Chapter 9. 1 --- Introduction --- p.182 / Chapter 9.2 --- Problem Statement --- p.183 / Chapter 9.3 --- The Turnpike Property --- p.190 / Chapter 9.4 --- Existence of Overtaking Optimal Solutions --- p.196 / References --- p.198 / Chapter Chapter 10. --- Viable Control in Logistic Populatiuon Model / Chapter 10. 1 --- Introduction --- p.199 / Chapter 10. 2 --- Viable Control --- p.200 / Chapter 10.3 --- Minimum Time Problem --- p.205 / References --- p.208 / Author's Publications During the Candidature --- p.209

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