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In a recent paper, Wagner and Graf derived a population evolution equation for an ensemble of convective plumes, an analog with the Lotka–Volterra equation, from the energy equations for convective plumes provided by Arakawa and Schubert. Although their proposal is interesting, as the present note shows, there are some problems with their derivation.

The apiarian and agricultural sectors got together to set up an apiary survey in Eure-et-Loir, in 2010, during oilseed rape flowering. The aim of this observatory was to highlight what can occur during oilseed rape flowering regarding bee population evolution and agricultural practices. The year 2010 was marked by important larvae and brood mortalities which induced a national investigation. Among the 4 surveyed apiaries, 2 were also concerned by these mortalities but this could not be explained by the observations and the analysis that were carried out. However, this survey enabled us to identify apiarian and agricultural practices around the apiaries and to combine expert testimonies of apiarian and agricultural professionals.

In this paper, we proposed a LW-PSO (PSO using a local world evolving model) by combining a local world evolving model with the “survival of the fittest” evolution mechanism. The concept of population structural entropy, a new diversity measure is defined and used to control the evolution process of the population topology of LW-PSO so the balance between the exploration and exploitation can be preserved during the population evolution. The experimental results show that LW-PSO can outperform the standard PSO with the lbest topology and the gbest topology especially in the multimodal problems and the extra time cost is negligible.

Is there an overriding principle of nature, hitherto overlooked, that governs all population behavior? A single principle that drives all the regimes observed in nature - exponential-like growth, saturated growth, population decline, population extinction, oscillatory behavior? In current orthodox population theory, this diverse range of population behaviors is described by many different equations - each with its own specific justification. The signature of an overriding principle would be a differential equation which, in a single statement, embraces all the panoply of regimes. A candidate such governing equation is proposed. The principle from which the equation is derived is this: The effect on the environment of a population's success is to alter that environment in a way that opposes the success., Comment: Revised equation-numbering to correspond to published version

Aims: A research was undertaken to explore the possibility to use Biolog system of microbial metabolic characterization for the monitoring of yeast population evolution during alcoholic fermentation for wine production. Methods and Results: An application of Biolog system was employed for the characterization of yeasts of oenological interest, in pure cultures and mixed consortia, in various cell concentrations. The system’s capacity to discriminate among different cell concentrations of the same yeast strain was ascertained, along with the capacity to discriminate between mixed and pure populations. Conclusions: The tested application of Biolog system resulted suitable for a quick recognition (24 h) of the presence of starter cultures within mixed populations of autochthonous yeasts. Such discrimination was confirmed with the one resulting from molecular techniques. Significance and Impact of the Study: The study suggests the possibility to employ Biolog system for an early monitoring of yeast evolution in modern wine-making fermentations, where specialized yeasts are more and more frequently used as starters and their ability to overcome autochthonous yeast populations is crucial.

In recent years, evaluating graph distance has become more and more important in a variety of real applications and many graph distance measures have been proposed. Among all of those measures, structure-based graph distance measures have become the research focus due to their independence of the definition of cost functions. However, existing structure-based graph distance measures have low degree of precision because only node and edge information of graphs are employed in these measures. To improve the precision of graph distance measures, we define substructure abundance vector (SAV) to capture more substructure information of a graph. Furthermore, based on SAV, we propose unified graph distance measures which are generalization of the existing structure-based graph distance measures. In general, the unified graph distance measures can evaluate graph distance in much finer grain. We also show that unified graph distance measures based on occurrence mapping and some of their variants are metrics. Finally, we apply the unified graph distance metric and its variants to the population evolution analysis and construct distance graphs of marker networks in three populations, which reflect the single nucleotide polymorphism (SNP) linkage disequilibrium (LD) differences among these populations.

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A general population evolution model is considered. Any individual of the population is characterized by its score. Certain general conditions are assumed concerning the number of the individuals and their scores. Asymptotic theorems are obtained for the number of individuals having a fixed score. Then it is proved that the score distribution is scale free. The result is applied to obtain the weight distribution of cliques in a random graph evolution model.

trees sifter 1.0 implements an approximate method to estimate the time to the most recent common ancestor (TMRCA) of a set of DNA sequences, using population evolution modelling. In essence, the program simulates genealogies with a user-defined model of coalescence of lineages, and then compares each simulated genealogy to the genealogy inferred from the real data, through two summary statistics: (i) the number of mutations on the genealogy (Mn), and (ii) the number of different sequence types (alleles) observed (Kn). The simulated genealogies are then submitted to a rejection algorithm that keeps only those that are the most likely to have generated the observed sequence data. At the end of the process, the accepted genealogies can be used to estimate the posterior probability distribution of the TMRCA.

This paper examines the introduction of neutrality as proposed by Kimura (Kimura, 1968) into the genotype-phenotype mapping of a Genetic Algorithm (GA). The paper looks at the evolution of both a simple GA (SGA) and a multi-layered GA (MGA) incorporating a layered genotype-phenotype mapping based on the biological concepts of Transcription and Translation. Previous research in comparing GAs often use performance statistics; in this paper an analysis of population dynamics is used for comparison. Results illustrate that the MGA population’s evolution trajectory is quite different to that of the SGA population over dynamic landscapes and that the introduction of neutrality implicitly maintains genetic diversity within the population primarily through genetic drift in association with selection. peer-reviewed

In the origin of life community there has been a dispute about whether metabolism or replication came first. Yet both of these approaches are in implicit agreement that the first forms of life were basically passive. That shared assumption has begun to be challenged by a new generation of metabolism-first approaches, emphasizing that movement and adaptive behavior could have played an important role right from the start. After introducing recent research on this behavior-based approach to the origin of life, I offer a preliminary assessment of what this new approach implies for the origins of the genetic system. Current state of the field Metabolismand replicator-first approaches, while differing in many respects, implicitly agree that the first forms of life were passive and encapsulated individuals. Both failed to consider the intermediate timescales between chemical self-constitution and population evolution: no mention is made of motility nor of development (Froese et al., 2011). Yet new metabolismfirst approaches emphasize that motility and adaptive behavior could have played a crucial role from the start (Froese et al., 2014; Hanczyc, 2011; Egbert et al., 2012). Such a behaviorbased approach can refresh thinking on several classic issues. For example, it was long believed that pre-biotic evolution of a hypercycle of autocatalytic processes is unstable because it can be invaded by parasitic compounds. But later on it was realized that this is only the case in a well-mixed (non-spatial) environment, while spatial embedding can make hypercycles immune to parasites. We can push this change in perspective even further. It has been shown that it is possible to make use of the instabilities introduced by the parasites as a source of spontaneous motility, a capacity which can be adaptive under some conditions (e.g., Froese et al., 2012). Indeed, there may even have been forms of minimal cognition already at the origin of life (Hanczyc & Ikegami, 2010).

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In this work, we study the differentiability of the stationary age-dependent population system based on parity progression. By using the semigroup approach, we prove that the solution semigroup of the population evolution equation is eventually differentiable.

We present a simulation model based on the Penna model to study the population evolution. The wealth of the individual is considered in the model. We define increasing ratio α and decreasing ratio β of the wealth presenting the individual wealth variation, also define minimum wealth PROMO which works when one reproduces. We study the influence of α and β on a species' survival or downfall, and the influence of PROMO on the age distribution of a species. According to the different values of α and β, we find diverse regimes where a species will survive or die out, and even the regime where species' survival or downfall are very sensitive. We study the relation between life expectancy and the wealth of the individual, finding that life expectancy doesn't increase but decrease a little when the wealth of the individual increases.

In this paper, by using semigroup approach, we concerned with the regularity of the age-dependent population system with instantaneous time delay in the birth process. We prove that, under some additional condition, the solution semigroup { T ( t ) , t ⩾ 0 } of the population evolution equation is eventually differentiable, i.e., there exists t 0 > 0 such that T ( t ) is differentiable for t > t 0 .

- The Aosta Valley region displays at the same time a strong demographic growth in the Plain, the narrow strip of lowlands along the Dora Baltea river (1861/2001, + 162 %) and depopulation in the highlands i.e. the Mountains (1861/2001, - 36 %). Along the line of official statistics this paper analyzes the development of this phenomenon during 140 years, from 1861 to 2001. This study demonstrates that in the Mountains the patterns and causes of depopulation are different in the period 1861-1961 from the following period. In the first period the cause of depopulation is the preceding overpopulation, responsible of endemic poverty. After 1961, although, demographic pressure diminished and life quality improved, depopulation carried on because of the objective difficulties of Mountains to adapt itself to the market economy, and because of a strong pattern of decreasing birth rate in the vast majority of mountain communities. Those who relinquish their villages in the high valleys do not emigrate in far away countries as they used to, but find new homes in the Plain, where urbanization is increasing year by year., Résumé. - La région du Val d'Aoste est caractérisée à la fois par une forte croissance démographique dans la Plaine, le long ruban de terres basses qui bordent le lit de la Doire Baltée (entre 1861 et 2001, + 162 %), et par le dépeuplement des terres hautes de la Montagne (entre 1861 et 2001, - 36 %). Le phénomène est analysé d'après les statistiques officielles, au cours de 140 ans, de 1861 à 2001. Cette étude révèle que dans la Montagne les modalités et les causes du dépeuplement après 1961 ne sont pas les mêmes que dans la période précédente (1861-1961). Avant 1961, les causes remontent au surpeuplement antérieur qui avait provoqué une pauvreté générale. Après 1961, en dépit d'une atténuation de la pression démographique intérieure et de l'amélioration des conditions de vie, le dépeuplement se poursuit en raison des difficultés de la Montagne à s'adapter à l'économie de marché et de la forte dénatalité dans la plupart des communes montagnardes. Ceux qui abandonnent les villages des hautes vallées n 'émigrent plus, comme autrefois, vers des pays lointains, mais ils s'établissent dans la Plaine où l'urbanisme augmente au fil des ans., Cerutti Augusta Vittoria. «Le dépeuplement dans le Val d'Aoste : les causes et les conséquences» (Depopulation in Aosta valley : causes and consequences). In: Bulletin de l'Association de géographes français, 80e année, 2003-1 ( mars). la montagne : milieux, aménagement, paysages, sous la direction de Henri Rougier. pp. 23-30.

Enrichment of mixed microbial cultures (MMCs) in polyhydroxyalkanoate (PHA)-storing microorganisms must take place to develop a successful PHA production process. Moreover, throughout the operational period of a MMC system, the population needs to be checked in order to understand the changes in the performance that eventually occurred. For these reasons, it is necessary to monitor the population evolution, in order to identify the different groups of microorganisms and relate them with the storage capacity and kinetics of the MMC. Regarding this particular process, several culture-independent molecular techniques were already applied, with the use of hybridization techniques such fluorescence in situ hybridization and also PCR-based methods like denaturing gradient gel electrophoresis, terminal restriction fragment length polymorphism, pyrosequencing, and quantitative PCR standing out. This review intends, thus, to look at the molecular methods currently applied in monitoring the PHA-storing population evolution and how they can be combined with the evolutionary engineering step in order to optimize the overall process.

We analyze the evolution of a Cantabrian chamois population affected by sarcoptic mange over a twelve-year period, from 1991 to 2002. This population is spread out over 83,000 ha and has reached an average density of 12.3 chamois/100 ha. The epidemic appeared an 1993, however the population continued to increase until 1995, after which it began to decrease reaching its minimum in 2001. Currently there are 35.9% of the specimens that were in evidence in 1995. The annual variation of population in sectors affected by sarcoptic mange was considerable, with maximum losses between 30-48%. The heaviest losses occurred between the first and the third year after the epidemic entered the area. Five or six years after the beginning of the epidemic, the population stablilized at a density level of 4.1-6.4 specimens/100 ha., [fr]Durant une période de 12 ans, entre 1991 et 2002, nous avons analysé l'évolution d'une population d'isard cantabrique qui a été affectée par une épidémie de gale. La population s'étend sur 83 000 ha, la densité étant de 12,3 isards/100 ha. Malgré le fait que l'épidémie soit apparue en 1993, la population a continué à augmenter jusqu'à 1995, puis a baissé jusqu'à un minimum en 2001. Actuellement, la population représente 35,9% de celle de 1995. La variation annuelle de la population dans les secteurs affectés par la gale était considérable, avec des pertes maximales entre 30 et 48%. Ainsi la plus forte perte a eu lieu entre la première et la troisième année après l'arrivée de la maladie. Puis, cinq ou six ans après l'initiation de l'épidémie, la population s'est stabilisée à un niveau de densité de 4,1-6,4 individus/100 ha. [es]Se analizó la evolución de una población de rebeco cantábrico afectada por sarna sarcóptica entre 1991 y 2002. Esta población abarca 83.000 hay ha alcanzado una densidad media de 12,3 rebecos/100 ha. La epidemia comenzó en 1993, aunque la población continuó aumentando hasta 1995, tras lo que empezó a decrecer, alcanzando su mínimo en 2001. Actualmente la población representa el 35,9% de la existente en 1995. La variación poblacional anual en zonas afectadas por la sarna sarcóptica fue considerable, con pérdidas máximas entre 30-48%. Las mayores mortalidades ocurrieron entre el primer y el tercer año tras la aparición de la epidemia en la zona. Cinco o seis años antes de la epidemia, la población se había estabilizado en una densidad de 4,1-6,4 individuos/100 ha.

Clinical trials in severely diseased populations often suffer from a high dropout rate that is related tothe investigated target morbidity. These dropouts can bias estimates and treatment comparisons,particularly in the event of an imbalance. Methods to describe such selective dropout are presentedthat use the time in study distribution to generate so-called population evolution charts. These chartsshow the development of a distribution of a covariate or the target morbidity measure as it changes asa result of the dropout process during the follow-up time. The selectiveness of the dropout process withrespect to a variable can be inferred from the change in its distribution. Different types of selectivedropout are described with real data from several studies in metastatic bone disease, where markedeffects can be seen. A general strategy to cope with selective dropout seems to be the inclusion ofdropout events into the endpoint. Within a time-to-event analysis framework this simple approach canlead to valid conclusions and still retains conservative elements. Morbidity measures that are based on(recurrent) event counts react differently in the presence of selective dropout. They differ mainly inthe way dropout is included. One simple measure achieves good performance under selective dropoutby introducing a non-specific penalty for premature study termination. The use of a prespecifiedscoring system to assign a weight for each works well. This simple and transparent approach performswell even in the presence of unbalanced selective dropout. Copyright # 2002 John Wiley & Sons Ltd.Keywords: dropout; oncology; population evolution chart; imbalance; morbidity measures

We consider a two-dimensional model for the evolution of a population consisting of two subgroups. The model is described by a system of differential equations. A qualitative analysis of the system is conducted for various parameter values. Bifurcations of phase portraits are described. An example is considered.

Brettanomyces bruxellensis and the consequences of its development in wines are a continuous threat for wine quality. In this context, chitosan of fungal origin was introduced as a new tool to control B. bruxellensis in the context of winemaking. Recent studies have showed the impact of a fungal origin chitosan application on wines contaminated with B. bruxellensis, leading to the elimination of B. bruxellensis cells. In these studies, the chitosan preparation was added, the wine racked off after 10 days and the efficiency of the treatment was evaluated in a short delay after the treatment. This study focused on the evaluation of the impact of different addition protocols of an enological chitosan preparation on B. bruxellensis population evolution and volatile phenols content along the aging, up to 9 months. The results confirm the interest of fungal origin chitosan as a preventive tool to control B. bruxellensis in the context of wine aging.

This paper presents an application of a metapopulation model structured in classes for the study of population evolution of a network of schools. The global dynamics are considered in two parts, the local, where the evolution for each grade in a cycle is accounted, and the metapopulation or the movement of students between schools. Simulation of the model is presented.

The paper presents some results obtained at the Department of Stability of Processes of the Institute of Mechanics of the NASU in the following areas: the nonclassical theories of stability of motion, the method of integral inequalities, the comparison method, stability of large-scale systems, stability analysis of motions in nonlinear mechanics, matrix-valued Lyapunov functions and their application, and qualitative analysis of population evolution. The characteristic features of the development of stability theories at the end of the 20th century are discussed in the final section

Pulse propagation in the pure-state three-level medium called phaseonium by Marlan Scully is studied both analytically and numerically. Distinctions between SIT-type pulses (e.g., simultons) and EIT-type pulses are most naturally revealed by making use of dark and bright dressed-state amplitudes. We show that EIT-type and SIT-type pulses propagating in phaseonium are to be distinguished by the type of population evolution that they induce.

In this paper we present an optimization approach based on the combination of a Genetic Algorithms maximization procedure with a Monte Carlo simulation. The approach is applied within the context of plant logistic management for what concerns the choice of maintenance and repair strategies. A stochastic model of plant operation is developed from the standpoint of its reliability/availability behavior, i.e. of the failure/repair/maintenance processes of its components. The model is evaluated by Monte Carlo simulation in terms of economic costs and revenues of operation. The flexibility of the Monte Carlo method allows us to include several practical aspects such as stand-by operation modes, deteriorating repairs, aging, sequences of periodic maintenances, number of repair teams available for different kinds of repair interventions (mechanical, electronic, hydraulic, etc.), components priority rankings. A genetic algorithm is then utilized to optimize the components maintenance periods and number of repair teams. The fitness function object of the optimization is a profit function which inherently accounts for the safety and economic performance of the plant and whose value is computed by the above Monte Carlo simulation model. For an efficient combination of Genetic Algorithms and Monte Carlo simulation, only few hundreds Monte Carlo histories are performed for each potential solution proposed by the genetic algorithm. Statistical significance of the results of the solutions of interest (i.e. the best ones) is then attained exploiting the fact that during the population evolution the fit chromosomes appear repeatedly many times. The proposed optimization approach is applied on two case studies of increasing complexity.

A three-dimensional mathematical model of nonhomogeneous population dynamics with selection and birth-and-death processes is considered. Bifurcations of operating modes are determined and conditions for extinction, degeneration, and stabilization are established.

Computer study of population evolution in a modified Penna model is presented, where different thresholds T for bad mutation may be assigned to individuals. The model indicates a possible source of such fluctuations of T due to embryo period of life before birth. Changes in age characteristics of the population, survival rate and mutation distributions at equilibrium are discussed. Results of computer simulation are compared with the standard Penna model with no fluctuation in T. We obtained larger equilibrium population for the same environmental capacity. However, the survival rate is smaller and the age of the oldest individuals also decreases. This is also reflected in age distribution of the population, similar at older populations and with higher decrease rate among younger ones. Also, the mutation accumulation is similar for older ages, yet younger individuals may absorb more mutations as a result of the presence of some items with threshold value above the average T. We conclude that fluctuations in threshold T may alter population characteristics, also in terms of measurable statistics in population such as age distribution or the survival rate.

We propose, and solve via Monte-Carlo simulation, a model describing evolution of population subject to harmful mutations. The habitat changes periodically. The evolution of two, initially identical, populations is compared. One without any external ingerence and the second in which we eliminate all individuals which are ill-fitted to the changed environment (eugenics). We show that although in the short run the individuals in the latter are better adapted and live longer, after some more changes of the environment, the populations with eugenics become extinct, while the others live on.

Under the effect of strong genetic drift, it is highly probable to observe gene fixation or gene loss in a population, shown by singular peaks on a potential landscape. The genetic drift-induced noise gives rise to two-time-scale diffusion dynamics on the bipeaked landscape. We find that the logarithmically divergent (singular) peaks do not necessarily imply infinite escape times or biological fixations by iterating the Wright-Fisher model and approximating the average escape time. Our analytical results under weak mutation and weak selection extend Kramers's escape time formula to models with B (Beta) function-like equilibrium distributions and overcome constraints in previous methods. The constructed landscape provides a coherent description for the bistable system, supports the quantitative analysis of bipeaked dynamics, and generates mathematical insights for understanding the boundary behaviors of the diffusion model.

This paper presents a hybrid coding collaborative ant colony-differential evolution algorithm for solving bound constrained mixed integer programming problems. In this algorithm, a real number and integer hybrid coding strategy is used, and the population evolution is realized by colony optimization and differential evolution. It is shown by numerical experiments that the proposed algorithm is effective. The proposed algorithm is combined with penalty function method to solved the general mixed integer programming problems. Numerical experiments show that the proposed method achieves satisfactory results.

The last census of 20 October 2011, confirmed the decrease in the stable population in most localities, although this did not occur uniformly across the county. The analysis aims to highlight the stable population evolution in the last two censuses, which mainly led to decreases in existent disparities between localities, to a slight increase of the degree of uniformity in this regard. If in urban areas, all localities have recorded drops, in the rural areas there were 11 localities with population increases, especially large suburban cities. This led to a slight decrease in the degree of variation in the area, from a coefficient of 45,6% at the census of 2002 to 43,4% in 2011 and the reduction in the ratio of the largest and smallest area, from 7,84 times to 6,08 times. If in 2002 there were 21 local rural residents under 3000 inhabitants, in 2011 their number increased to 26, while more than 10 thousand people do not exist in any village in the county, compared to 2 as they were at the previous census. Territorial disparities are found also among the population by age, existing only 8 villages where the average age has decreased compared to 2002, these being mainly poor localities from Valea Siretului, where the birth rate is higher.

Cette étude porte sur la dynamique des populations de Varroa destructor dans trois écosystèmes du nord d'Algérie à climat méditerranéen humide ou Mitidja, continentale semi-aride des hauts plateaux et continentale aride de la steppe. Des observations mensuelles ont été effectuées, de janvier 2010 à aout 2012, sur 18 colonies réparties entre 3 ruchers tout au long de la bande nord de l'Algérie. Les populations d'abeilles n'ont pas subi de traitement acaricide. Le développement des populations d'acariens est étudié en tenant compte de la mortalité naturelle, du taux d'infestations des abeilles adultes et du taux d'infestation du couvain. Pour la mortalité naturelle, il y a des différences significatives entre les années où on enregistre une évolution importante entre les mois de mars et août avec un maximum de 577, 494 et 373 respectivement pour la Mitidja, les hauts plateaux et la steppe. Nous avons constaté une régression qui s'annule de septembre à février. Les taux d'infestation des abeilles adultes pour les trois types de climat sont respectivement de: 6,13; 6,09 et 4,81% pour 100 abeilles ouvrières. Il en est de même pour le maximum des taux d'infestation du couvain qui varie en fonction de la zone climatique. Les valeurs globales pour les trois écosystèmes étudiés s'établissent à: 7,16 pour la Mitidja, 6,55 pour les hauts plateaux et 5,39% pour la steppe. Ces valeurs baissent en passant du climat humide au sec. Les taux d'infestation diminuent sensiblement dans le temps. Este estudo debruça-se sobre a dinâmica das populações de Varroa destructor em três ecossistemas do norte da Argélia, com clima mediterrânico húmido como em Mitidja, continental semi-árido nos altos planaltos e continental árido na estepe. Efectuaram-se observações mensais, de janeiro de 2010 a agosto de 2012, em 18 colónias repartidas por três apiários ao longo da costa norte da Argélia. As populações de abelhas não foram tratadas com acaricidas. O desenvolvimento das populações de ácaros é estudado tendo em conta a mortalidade natural, a taxa de infestação das abelhas adultas e a taxa de infestação das larvas. Quanto à mortalidade natural, existem diferenças significativas entre os anos, e regista-se uma evolução importante entre os meses de março e agosto, com um máximo de 577, 494 e 373 respetivamente para Mitidja, os altos planaltos e a estepe. Constatámos uma regressão, que se anula de setembro a fevereiro. Nos três tipos de clima, a taxa de infestação das abelhas adultas é de, respetivamente, 6,13 ; 6,09 e 4,81% por 100 abelhas obreiras. O mesmo se passa com a taxa de infestação das larvas, que varia em função da zona climática. Os valores globais para os três ecossistemas estudados são os seguintes: 7,16 para Mitidja, 6,55 para os altos planaltos e 5,39% para a estepe. Estes valores baixam ao passar do clima húmido ao seco. As taxas de infestação diminuem sensivelmente com o passar do tempo. This experiment is performed on the dynamics of the population of the ectoparasitic Varroa destructor in northern Algeria where there are climatic differences from north to south. Monthly observations were conducted from January 2010 to August 2012, in 18 colonies in three apiaries distributed throughout the northern strip of Algeria. Bee populations have not undergone any acaricide treatment. Our experiment is undertaken in the areas corresponding to the following three climatic regions: Mediterranean climate or wet Mitidja (CM), Continental semiarid highlands (CSA) and continental arid steppe (CA). The development of mite populations is studied taking into account the following parameters: natural mortality (M) rates infestations of adult bees (TIA) and infestation rate of brood (ICT). For natural mortality, there are significant differences between the years, there has been a significant change during the period from March to August with a maximum of infestation of 577, 494 and 373 respectively for Mitidja highlands and steppe, which decreases to cancel from September to February. The infection rate of bees (TIA) for the three types of climate is respectively: 6.13, 6.09 and 4.81%. It is the same for the maximum infestation rate of brood, which varies depending on the climate zone. Global values for the three ecosystems studied are as follows: 7.16% for Mitidja, 6.55% for the highlands and 5.39% for the steppe. These values decrease from humid to dry climate. Infection rates decreased significantly over time.

This paper studies the improvement of parallel genetic algorithm. It mainly focuses on the application of adaptive crossover and adaptive mutation to achieve AGA in the population evolution of SGA. It also investigates the application of adaptive strategy to achieve AMPGA in the migration of PGA. On this basis, it puts forward a new algorithm APGA and demonstrates the feasibility and superiority of APGA by providing solutions to functions.

Dispersal and reproduction are fundamental elements in the life-cycle of every biological organism. As a result, if one needs to understand population evolution within timescales of the order of the individual lifespan of larger, then one needs to deal with reaction-dispersal models, where reaction is the technical term to designate birth and death processes.

Firefly algorithm is a bionic random algorithm for solving complex optimisation problems. Any firefly will be attracted to other better fireflies to complete the population evolution. In this method, the better fireflies only show the advantages of them, but do not represent that of swarm. In order to enhance information exchange between the swarms, different learning time of the general central particle is embedded into the particle update phase. So, we propose the general central firefly algorithm based on different learning time. Correspondingly, three variants of general central FA are generated, namely, the algorithms based on one-to-one (OO) learning time, one-to-all (OA) learning time and all-to-all (AA) learning time. Experiments are tested on 12 benchmark functions. The results show that the optimisation performance of three algorithms are better than that of the standard FA. OOFA algorithm has the best optimisation performance.

Computer experiment study of population evolution and its dynamics is presented for two competing species A and B which share two habitats (1 and 2) of limited environmental capacity. The Penna model of biological aging, based on concept of defective mutation accumulation was adopted for migrating population. In this paper we assume and concentrate on the case when only one species A is mobile. For isolated habitats and for any initial population, we get at equilibrium spatial population distribution (A, B) between the two locations - A occupies location 1 while B-species is present in 2. The effect of migration between habitats is reported for some migration scenarios. With increasing migration we get a sequence (A, B) -> (A, A&B) -> (A, A) -> (B, B) distribution. Another scenarios bring different sequences of population distribution, size and characteristics.

We explore with the use of multicore processing technologies for conducting simulations on population replacement of disease vectors. In our model, a native population of simulated vectors is inoculated with a small exogenous population of vectors that have been infected with theWolbachiabacteria, which confers immunity to the disease. We conducted a series of computational simulations to study the conditions required by the invading population to take over the native population. Given the computational burden of this study, we decided to take advantage of modern multicore processor technologies for reducing the time required for the simulations. Overall, the results seem promising both in terms of the application and the use of multicore technologies.

Fiber-to-the-Home (FTTH) has been talked about since the introduction of fiberin the 1970s. It is nowadays shaping up to be the foundation of our newdigital society, bringing economic prosperity and a multitude of business,social, and entertainment opportunities to its users. The increased consumerdemand for high-speed network accessibility is being taken more and moreseriously and a fiber-based network is able to cope with these growing demandsdue to its wide bandwidth and reliability. Today there is a practical need forquantitative analysis regarding the socio-economic impacts of fiber-basedaccess networks. This analysis could be used as an indicator/reference for allthe stakeholder entities as they consider future investments anddevelopments. Sweden is a suitable target country for this analysis since ithas adopted fiber for some years and the benefits that FTTH has brought seemto already be tangible. The primary value of this thesis lies ininvestigation of its quantified evidence of the socio-economic impacts of FTTHdeployment in Sweden. This has been achieved based on data from the SwedishPost and Telecommunications Authority (PTS), Statistics Sweden (SCB), previousrelated studies, and information collected on-line from operators involved inthe fiber market, along with empirical analysis based on multivariateregression models. The results of the study show that fiber penetrationhas had a significant impact on the population’s evolution, specially the netamount of migration into a municipality, which indicates the attractiveness ofmunicipalities per se. It is therefore reasonable to suggest that localgovernment and local authorities take fiber deployment into consideration, ifthey want to attract people to stay for further local development. The studyalso analyzed the competition in fiber-based open networks and the prices ofsubscribing for 10/10 Mbps symmetrical Internet Service. Study findingsrevealed that networks with multiple competing service providers have a widerrange of services and a lower price: the more ISPs competing in a fibernetwork, the lower consumer prices. Specifically, for each new serviceprovider present in the network, there will be 5 SEK per month decrease of theaverage price of the Internet services, and an approximately 7 SEK per monthreduction in the lowest price. Nevertheless, a number of socio-economicimpacts remain unquantifiable as of the current time and due to the limitedavailable data. It is recommended to incorporate more socio-economic effectsin future research in order to draw a more complete picture for all theinterested sectors, and to supplement the data with recent figures for 2012and 2013. Fiber till hemmet (Fiber-to-the-Home, FTTH) har talats om sedan fiberintroducerades på 1970-talet. Det håller numera på att bli grunden för vårtnya digitala samhälle, och bidra till ekonomiskt välstånd och medföra en mängdaffärsmässiga, sociala och underhållningsmässiga möjligheter tillslutanvändare. Den ökade efterfrågan på höghastighetsnät tas mer och mer påallvar och ett fiberbaserat nät kan hantera dessa ökade krav på grund av dessbreda bandbredd och tillförlitlighet. Idag finns ett praktiskt behov avkvantitativ analys av de socioekonomiska effekterna av fiberbaseradeaccessnät. Denna analys kan användas som en indikator och referens för allaintressenter när de överväger framtida investeringar. Sverige är ett lämpligtmålland för denna analys eftersom den har antagit fiber i några år och defördelar som FTTH har fört verkar redan vara synliga. Det huvudsakligavärdet av denna avhandling ligger i utredningen av kvantifierade bevis för desocioekonomiska effekterna av FTTH utbyggnad i Sverige. Detta har uppnåtts pågrundval av uppgifter från den Post- och telestyrelsen (PTS), Statistiskacentralbyrån (SCB), tidigare liknande studier och information som samlats inpå nätet från aktörer inom fiber, tillsammans med empirisk analys baserad påmultivariate regressionsmodeller. Resultatet visat att fiber har haft enbetydande inverkan på befolkningens utveckling, speciellt netto in- ochutflyttning till en kommun, vilket indikerar attraktionskraft kommunerna isig. Det är därför rimligt att föreslå att kommunerna och de lokalamyndigheterna överväger fiber driftsättning på allvar om de vill lockainvånare att stanna för ytterligare lokal utveckling. Studien analyserar ocksåkonkurrensen på fiberbaserade öppna nät och priserna på 10/10 Mbps symmetriskInternet-tjänst. Resultaten visar att nätverk med flera konkurrerandetjänsteleverantörer har ett bredare utbud av tjänster och ett lägre pris: jufler Internetleverantörer i ett fibernät, desto lägre konsumentpriser. Merspecifikt, för varje ny tjänsteleverantör som finns i nätverket, minskar detgenomsnittliga priset med 5 kronor per månad, och det lägsta priset med cirka7 kronor per månad. Ändå förblir ett antal socioekonomiska effekteromätbara på grund av begränsade tillgängliga data. Rekommendationen är attinförliva fler socioekonomiska effekter i framtida forskning för att dra enmer komplett bild för alla berörda sektorer, och att komplettera data medfärska siffror för 2012 och 2013.

In this paper, an ADaptive Immune Algorithm (ADIA) based on the artificial immune system (AIS) is proposed for the dependent task scheduling on Network on Chip (NoC). We increase the diversity of population of AIS in two ways, and improve the output result of scheduling. On one hand, new calculation method of the number of clones and the probability of mutation are proposed to enlarge the search space appropriately. On the other hand, our algorithm adopts an adaptive strategy to enable the local search to drive the population evolution when evolution speed is low after many iterative processes. Moreover, the influences of different factors in the proposed algorithm are studied. The comparative simulation results show that our algorithm always outperforms the tradition algorithms. Keywords-component; AIS; Dependent Task Scheduling; Network on Chip; Population Diversification; Adaptive

The research aims to observe the behavior of the acetic acid bacteria A. senegalensis during cider vinegar fermentation, respectively the cell population evolution and the acetate production ability in a cider medium.

Brazilian demography has gone through profound transformations in the last 50 years, in particular under the prism of internal migration and tendencies of fecundity decline. These changes promote huge, challenging impacts. In this context, State of Paraná is no exception to the rule. The objective of this article is to present a comprehensive presentation of the state’s demographic dynamics through the last decades. It highlights changes, regional diversity, directions and associated repercussions. La demografía brasileña ha vivido profundas transformaciones en los últimos 50 años, en particular en el ámbito de las migraciones internas y de las tendencias de declive de la fecundidad. Los impactos de esos cambios son grandes y desafiadores. En ese contexto, el estado del Paraná no huye de la regla. Así, el objetivo de este artículo es presentar un panorama de la dinámica demográfica paranaense en las últimas décadas, subrayando alteraciones, diversidades regionales, rumbos y las repercusiones que de ahí emergen. A demografia brasileira tem atravessado profundas transformações nos últimos 50 anos, em particular sob o prisma das migrações internas e das tendências de declínio da fecundidade. Os impactos dessas mudanças são enormes e desafiadores. Nesse contexto, o Paraná não foge à regra. Assim, o objetivo deste artigo é apresentar um panorama da dinâmica demográfica paranaense das últimas décadas, salientando alterações, diversidades regionais, rumos e as repercussões que daí emergem.

In this paper we present some recent work we performed on the socio-economic impact of fibre access networks (FTTH/FTTx). We summarise some results from a pre-study on the effects of fibre deployments in Sweden. Specifically, we list and quantify savings in data and telecommunications costs for Swedish local governments, estimate the added values for fibre-connected citizens, and present a multivariate regression analysis of the early impact on employment and population evolution, building on data from 290 municipalities between 2007 and 2010: we find a weak but statistically significant correlation, and we are able to exclude backward causality.

People’s movements, interactions and behaviours have always been at the centre of the modelling of complex social systems. This chapter introduces an individual-based, dynamic spatial microsimulation model that simulates the population evolution through the individual changes in various demographic processes at a fine spatial scale. Following discussions of the features of this model, details of the model design and development are described. The simulated results over the period of 30 years are also analysed and discussed.

We investigate a centrally-planned, infinite-horizon, single-good economy in which the labour force grows exogenously and new knowledge is generated in a separate R&D sector. Various balanced growth scenarios are studied and characterized, using a general production technology and a broad class of social utility functions.

Resources from the Internet, How to faster find the resources from cloud database, it is the database resource allocation algorithm cloud combinatorial optimization problem. Try buzzers and genetic algorithm fusion and normal cloud model algorithm, fast convergence to optimal solutions, and it improved phased efficiency of genetic algorithm from a optimal solution to an optimal solution.

This paper deals with the construction of a discrete mathematical model for addictive buying. Firstly, identifications of consumers buying behavior are performed by using multivariate statistical techniques based on real data bases and sociological approaches. Then the population is divided into appropriate groups according to the level of overbuying and a discrete compartmental model is constructed. The future short term addicted population is computed assuming several future economic scenarios. © 2010 Elsevier Ltd.

In the present paper propose two novel variants of Differential Evolution (DE), named IP-OBL and IP-NSDE, have been proposed. In IP-OBL the initial population is generated by using the intermediate positions between the uniformly generated random numbers and opposition based numbers. While in case of IP-NSDE, the initial population is generated as an intermediate of uniform random numbers and numbers generated by Nelder Mead Method. The proposed algorithms are further modified by selecting best NP/2 individuals to perform in population evolution. The modified variants are termed as MIP-OBL and MIP-NSDE. The numerical results of 10 benchmark problems indicate the competence of the proposed algorithms.