Most migrating songbirds are required to stopover to rest and replenish their fat reserves, and suitable stopover habitat is vitally important to their survival and success securing territories at their breeding and wintering grounds. Identifying and protecting stopover locations and movement corridors is essential to connecting all life stages of these species, yet there remain significant knowledge gaps regarding the utilization of stopover sites and fine-scale movements during migration, particularly at inland stopover areas. We investigated the factors that influence stopover duration and migration rate of ten migratory songbirds within the Silvio O. Conte National Fish and Wildlife Refuge in the Northeastern United States during two fall and spring seasons in 2015 and 2016 at 5 banding sites using automated telemetry. We expected that fat and mass would influence stopover duration and migration rate, in that birds with larger fat stores and greater masses would make shorter stopovers, and migrate faster than leaner birds. We also expected that birds would move faster in spring, and minimize time later in the season, by making shorter stopovers and migrating faster as the season progresses. A lower percentage of our focal species departed the banding sites within 24 hours compared to other studies in coastal and urban sites, indicating that more birds made stopovers. Sixteen percent of birds made prolonged stopovers (> 7 days) in spring, and 38 % in fall, highlighting the importance of the refuge for long term refueling. Spring birds made shorter stopovers, and traveled at faster rates than fall birds, suggesting there is may be more pressure for early arrival at breeding grounds. Spring birds captured with significant fat loads made shorter stopovers, and traveled faster than leaner birds. Spring birds also appeared to employ a time minimization strategy, with birds captured later in the season making shorter stopovers. Migration rate of spring birds decreased with distance from the capture site, indicating many birds needed to make additional stopovers. Fall birds that made longer stopovers migrated at faster rates. Fall birds captured later in the season made longer stopovers, and subsequently traveled at faster rates once they departed to possibly minimize time on migration. Variation in stopover behavior was evident among sites and species and this may suggest habitat or site characteristics that affect their value for migrating birds, which should be taken into consideration when conservation planning or vulnerable species. The extensive use of this inland National fish and wildlife refuge by migratory birds, and the fact that birds are acquiring energy reserves that are facilitating successful migration suggests this region is an important corridor for migrating songbirds.

This is a thesis conducted in San José, Costa Rica during two months in the spring of 2021. The purpose of this study is to explore what factors are causing migration from Nicaragua to Costa Rica, if the migration has included discrimination in any form and to what extend the staff at the non-governmental organizations Dale una mano a tu hermano (Give your brother a hand), and Ticos y Nicas (costaricans and nicaraguans) somos hermanos (Ticos y Nicas, are brothers) find their vision of integrating Nicaraguan refugees into Costa Rica possible.  The data for this project was collected through semi structured interviews with staff members at the non-governmental organizations “Dale una mano a tu hermano”, “Ticos y Nicas somos hermanos” and migrants from Nicaragua. The concepts of The Rational Choice Theory, Lee’s Push and Pull Migration Theory, and Hall’s theory of the “Other” was used as a theoretical framework to the thesis. The conclusion of this study is that migration from one country to another is caused by several factors, that migration can lead to discrimination in any form, and that the mentioned non-governmental organizations still find their work of integrating migrants into Costa Rica hard.

No description available.

’appuyant sur une ethnographie d’environ cinq ans, effectuee entre 2010 et 2015 dans la ville de Tanger, l’enquete presentee ici interroge les formes de mobilité et les pratiques économiques mises en place par des migrants originaires de l'Afrique de l'Ouest et exclus des circuits de la mobilité privilégiée. Je décris ces individus comme des self-made-migrants qui, ne disposant pas des moyens économiques, administratifs et relationnels leur permettant d'accéder aux cir-cuits de la mobilité privilégiée, construisent, par le bas, une mobilité transnationale et subalterne réalisée par étapes et contournements de frontières. Cette mobilité se configure comme un projet et est conçue par les migrants comme un moyen pour “chercher leur vie”, a savoir pour chercher de manière autonome de nouvelles opportunités et une émancipation économique et sociale et s'imposer ainsi comme les acteurs de leur destin. Cette quête est orientée moins par une desti-nation precise que par la volonte de “sortir” et de circuler dans un ailleurs indefini et ouvert qui devient le catalyseur des imaginaires de réussite de ces migrants. Cette mobilité se réalise par étapes, à travers des découvertes, des explorations, des allers-retours : les migrants inventent ainsi étape après étape des parcours singuliers en reformulant constamment leurs itinéraires en fonction des contraintes et des opportunités qui se présentent. À travers mon enquête j'explore la relation existant entre cette forme de mobilité transnationale subalterne et des pratiques économiques de la mobilité et de la débrouille que les migrants in-ventent et développent afin d'alimenter leur trajectoire. Ces pratiques relèvent d'une économie de la pauvreté, caractérisée par des revenus extrêmement modestes et aléatoires et par un manque complet de toute forme de protection. Je montrerai que ces pratiques s'ancrent dans les marges de l'économie régulière et se greffent sur d'autres formes de mobilités qui se croisent et s'imbriquent dans la région tangéroise : des mobilités touristiques et commerciales notamment. Ces pratiques sont en outre transposables et peuvent être déclinées de manière inédite lors des étapes futures des itinéraires de ces self-made-migrants. Ces self-made-migrants sont donc les acteurs d'une mobilité subalterne qui se fonde sur des pratiques économiques de la débrouille qui leur permettent de circuler sur des territoires trans-nationaux et alimenter ainsi leur quête d'émancipation économique et sociale. Mots-clés : self-made-migrants, migration, mobilité transnationale, économie de la mobilité, économie de la débrouille, émancipation économique et sociale, étape, Maroc. / Based on an ethnographic field, made between 2010 and 2015 in the Tangier city, this research seeks to find out how the West African moves excluded of the circuits of the mainstream migration, and the economical practices they use in order to move. I describe these individuals as the self-made-migrants, whom not having access to the economical, administrative and social resources to move, they create by they own means, a transnational and subordinate mobility made by stages and border circumventions. This mobility is understood as a project, and a way to “seek their life”. For them, this expression means to look autonomously new social and economic opportunities to become the main character of their destiny. This quest is not lead by the destination but by the will of “going out” and move in an indefinite elsewhere, which becomes the catalyst of the imaginations of success of these migrants. This mobility is made by stages, through discoveries, explorations, and roundtrips. The migrants create, step by step, singular journeys by constantly reformulating the itinerary, in order to respond to the opportunities and the difficulties they found on their quest. In this research I explore the relationship between this transnational subordinated mobility and the economical practices created by the migrants in order to continue the trip. These economical strategies take part of the economics of poverty, defined by lowest and random incomes, and by a lack of protection. I’ll show that these strategies are link to the regular economy and are related to other forms of mobility found in the Tangier region. These strategies are also easy to transpose and adapt to other contexts in other steps of the journey. The self-made migrants are the actors of a subordinated mobility based on a precarious economy that nonetheless allows them to continue their transnational journey and their pursuit of an economic and social emancipation. Key Words: self-made-migrants, migration, transnational mobility, economics of the mobility, precarious economy, social and economic emancipation, stage, Morocco.

Migrer à chaud une machine virtuelle (VM) est une opération basique dans un centre de données. Tous les jours, des VM sont migrées pour répartir la charge, économiser de l'énergie ou préparer la maintenance de serveurs. Bien que les problèmes de placement des VM soient beaucoup étudiés, on observe que la gestion des migrations permettant de transiter vers ces nouveaux placements reste un domaine de second plan. Cette phase est cependant critique car chaque migration à un coût en terme de CPU, de bande passante et d'énergie. Des algorithmes de décision reposent alors sur des hypothèses irréalistes et calculent des ordonnancements conduisant à des migrations longues et incontrôlables qui réduisent les bénéfices attendus de la ré-organisation des VM.Dans cette thèse nous nous sommes fixé comme objectif d'améliorer la qualité des ordonnancements de migrations dans les centres de données. Pour cela, nous avons d'abord modélisé l'ordonnancement de migrations en considérant l'architecture réseau et l'activité mémoire des VM. Pour évaluer l'efficacité de notre modèle, nous avons ensuite implémenté un ordonnanceur de migrations au sein du gestionnaire de VM BtrPlace. Nous avons ensuite étendu notre ordonnanceur en développant des contraintes d'ordonnancement, des objectifs personnalisés, une heuristique de recherche ainsi qu'un modèle énergétique.Nous avons validé notre approche par l'étude pratique de scénarios d'ordonnancement réalisés en environnement réel. Nous avons ainsi pu analyser la précision de notre modèle de migration, valider la qualité des décisions prises par notre modèle d'ordonnancement et évaluer l'extensibilité ainsi que le passage à l'échelle de notre solution / A live-migration of a virtual machine (VM) is a basic operation in a data center. Every day, VMs are migrated to distribute the load, save energy or prepare maintenance operations on production servers. Although VM placement problems have been extensively studied, we observe that the migrations management needed to apply these new placements did not get much attention. This phase is however critical as each migration has a cost in terms of CPU, bandwidth and energy. Decision algorithms are thus based on unrealistic assumptions and compute schedules which can lead to unnecessarily long and uncontrollable migrations. This reduces the ultimate benefits expected from the VMs re-organization.In this thesis, our main ojective is to improve the efficiency of live-migrations scheduling within data centers. To achieve our goal, we have first modeled the scheduling of live migrations based on the network architecture and the VMs memory activity. To evaluate the efficiency of our model, we have then implemented and optimized a migrations scheduler within the VMs manager BtrPlace. We have then extended our scheduler by developing scheduling constraints, custom objectives, a search heuristic and an energy model.We have validated our approach by the practical study of many scheduling scenarios executed in a real environment. We have then analyzed the accuracy of our migration model, assessed the quality of the decisions taken by our scheduling model, and evaluated the extensibility and the scalability of our solution

Magister Philosophiae - MPhil / The study analyses the changing patterns of international migration within the Southern African region. Topics surrounding migration are rapidly gaining importance, especially in the context of regional integration. Past research has focused primarily on South African migration, neglecting or, rather, paying less attention to the migration within other countries in the Southern African region. This study includes all the migration trends across the countries in Southern Africa while discussing contemporary migration trends within Southern Africa.

<div> <div> <div> <p>The motion of synthetic capsules and living cells in microchannels has been the subject of numerous studies in the last decade due to its significance in engineer- ing and biomedical applications. Cell sorting and separation are common processes that are used for various purposes such as separation of leukocytes from blood used in DNA sequencing. Isolation of rare cells in blood is needed for early diagnosis of lethal diseases such as cancer. Cell isolation and enrichment will also provide a better platform to biologists to study and analyze various properties of living cells. Thus, there is a high demand for developing techniques to precisely control trajectories of the cells and manipulate them in a desired manner. Microfluidic devices provide a platform to achieve aforementioned needs while overcoming challenges such as sample contamination, cost and complexity of the procedures. In many of these applications, the background fluid is non-Newtonian due to the presence of DNA and proteins, or polymers are added to control the trajectory of the cells. In this work, we first provide a fundamental study on the dynamics of a single deformable capsule in a viscoelastic matrix under a simple shear flow. Furthermore, we investigate the motion of a single cell and suspension of cells in microchannels. The effects of cell size, inertia, cell volume fraction, cell deformability and fluid elasticity are explored. Our findings on capsule motion in the viscoelastic medium suggest that the use of constant-viscosity viscoelastic fluid pushes the cells toward the channel centerline which can be used in microfluidic devices used for cell focusing such as cytometers. However, viscoelastic fluid with shear-thinning characteristics and drives the flowing cells toward the channel wall. Particle motion in viscoelastic matrix equilibrium positions of the particle in the microchannel for a wide range of inertial and elastic effects. These fundamental studies can provide insight on the role of rheological properties of the fluid that can be tuned to control the motion of the cells and particles for efficient design of microfluidic devices. </p> </div> </div> </div>

A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in partial fulfilment of requirements for the degree of Master of Science. Johannesburg, 2015. / The aim of this study was to model internal migration in South Africa using the 2011 Census data. The net-internal migration was modelled in the district municipalities of South Africa using Ordinary Least Squares (OLS) and Geographically Weighted Regression (GWR). In this study, the following global and local modelling techniques were used, Gravity, Poisson, Negative Binomial (NB), Gamma, and GWR model (local model). Poisson and NB failed to fit the migration data, while the Gamma model managed to fit the data reasonably well. The GWR model performed better than OLS regression in modelling net-internal migration in district municipalities of South Africa. The results from these models revealed that there was a strong relationship between internal migration and economic variables, as well as living conditions and demographic variables. The Monte Carlo significance test results showed that the parameters of the white population vary significantly across space. The results of the study signal that the differences in social and economic disparities in the district municipalities of South Africa are the drivers of internal migration.

Historically virtual machines have been the backbone of the cloud-industry, allowing cloud-providers to offer virtualized multi-tenant solutions. A key aspect of the cloud is its flexibility and abstraction of the underlying hardware. Virtual machines can enhance this aspect by enabling support for live migration and failover. Live migration is the process of moving a running virtual machine from one host to another and failover ensures that a failed virtual machine will automatically be restarted (possibly on another host). Today, as containers continue to increase in popularity and make up a larger portion of the cloud, often replacing virtual machines, it becomes increasingly important for these processes to be available to containers as well. However, little support for container live migration and failover exists and remains largely experimental. Furthermore, no solution seems to exists that offers both live migration and failover for containers in a unified solution. The thesis presents a proof-of-concept implementation and description of a system that enables support for both live migration and failover for containers by extending current container migration techniques. It is able to offer this to any OCI-compliant container, and could therefore potentially be integrated into current container and container orchestration frameworks. In addition, measurements for the proof-of-concept implementation are provided and used to compare the proof-of-concept implementation to a current container migration technique. Furthermore, the thesis presents an overview of the history and implementation of containers, current migration techniques, and metrics that can be used for measuring different migration techniques are introduced. The paper concludes that current container migration techniques can be extended in order to support both live migration and failover, and that in doing so one might expect to achieve a downtime equal to, and total migration time lower than that of pre-copy migration. Supporting both live migration and failover, however, comes at a cost of an increased amount of data needed to be transferred between the hosts.

In this case study, migration to and from Kristinehamn during the years 1840, 1865 and 1866 is examined. This time period is characterized by significant changes in form of urbanization, increased communication opportunities, changed business legislation and an incipient industrialization. With help of moving lengths from the church archives in Kristinehamn, migration patterns will be mapped due to a quantitative method. Information concerning the migrants' age, titles and moving company is reported. Migrants are also categorized based on how far they moved and on how long they stayed in the city. The survey has elements of a qualitative method as interpretation of the results is made with support of existing migration theories and previous research. The aim of this study is to investigate how the migration patterns changed during this time and to seek reasonable explanations for the demographic changes that can be shown through migration trends. The results show that the migration patterns change, in various aspects, between the different investigated time periods. For example, the proportion of family migrants had increased, and the distance of migration was stretched in the later period. The findings in this study also point at differences in migration patterns due to social affiliation.