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This study investigates the factors influencing the adoption and acceptance of cloud-based solutions within organizational contexts, emphasizing the strategic insights necessary for effective cloud migration. Cloud computing, marked by its scalability, has significantly transformed information technology landscapes. However, the adoption rates vary widely across industries, driven by diverse organizational, individual, and technological factors. This research adopts a qualitative methodology, employing interviews with stakeholders in various organizations to explore the complexities of cloud adoption. It explores how strategic, organizational, and individual factors influence the decision-making processes related to cloud services adoption. The findings highlight the role of perceived ease of use and organizational readiness in facilitating cloud adoption, challenging the emphasis on perceived usefulness. Strategic frameworks like the ARTIST methodology and AWS’s phase-driven approach are analyzed to reveal their strengths and shortcomings in actual business contexts. The study concludes that successful cloud migration requires a balanced approach that considers both technical and human factors, recommending future research to focus on these dimensions to enhance the efficacy of cloud migration strategies.

With the increased use of the internet and applications, the architecture has had to adapt to the increasing number of users. Many companies have started migrating from monolithic architecture to microservice and, more recently, started to explore the possibility of migrating applications to Function-as-a-Service. Among other things, companies such as OpenFaaS have helped teams with migrating to Function-as-a-Service architecture by providing orchestration and tools for overseeing the applications. This thesis aims to study the migration process of a behaviour-driven application built with Function-as-a-Service architecture. The investigation will focus on migration strategies that use the Strangler Fig Pattern in which the factors that affect the migration process will be analysed through a literature review and case study. The results of this research can be of help to organisations and teams to better understand the possibility of using Behaviour-driven Development in the development of Function-as-a-Service. Furthermore, the research will also highlight and bring insight into the factors that affect the migration process from monolithic to Function-as-a-Service by going through some of the disadvantages and advantages., Med den ökade användningen av internet och applikationer har arkitekturen fått anpassa sig till det ökande antalet användare. Många företag har börjat migrera från monolitisk arkitektur till mikrotjänst och nyligen börjat utforska möjligheten till att migrera till Function-as-a-Service. Bland annat har företag så som OpenFaaS hjälpt organisationer med att migrera till Function-as-a-Service-arkitektur genom att erbjuda orkestrering och verktyg för att övervaka applikationerna. Denna uppsatts syftar till att studera migreringsprocessen för en beteendedriven applikation byggd med Function-as-a-Service-arkitektur. Undersökningen kommer att fokusera på migreringsstrategi som använder Strangler Fig Pattern och kommer att analysera de faktorer som påverkar migreringsprocessen genom en litteraturstudie samt fallstudie. Resultaten av denna forskningsansats kan vara till hjälp för organisationer att bättre förstå möjligheten att använda beteendedriven utveckling för att utveckla Function-as-a-Service och möjligheten att migrera till Function-as-a-Service från en monolitisk arkitektur. Följaktligen kommer uppsatsen också att belysa de faktorer som påverkar migreringsprocessen från monolitisk till Function-as-a-Service genom att gå genom några av dess för- och nackdelar.

With the increased use of the internet and applications, the architecture has had to adapt to the increasing number of users. Many companies have started migrating from monolithic architecture to microservice and, more recently, started to explore the possibility of migrating applications to Function-as-a-Service. Among other things, companies such as OpenFaaS have helped teams with migrating to Function-as-a-Service architecture by providing orchestration and tools for overseeing the applications. This thesis aims to study the migration process of a behaviour-driven application built with Function-as-a-Service architecture. The investigation will focus on migration strategies that use the Strangler Fig Pattern in which the factors that affect the migration process will be analysed through a literature review and case study. The results of this research can be of help to organisations and teams to better understand the possibility of using Behaviour-driven Development in the development of Function-as-a-Service. Furthermore, the research will also highlight and bring insight into the factors that affect the migration process from monolithic to Function-as-a-Service by going through some of the disadvantages and advantages., Med den ökade användningen av internet och applikationer har arkitekturen fått anpassa sig till det ökande antalet användare. Många företag har börjat migrera från monolitisk arkitektur till mikrotjänst och nyligen börjat utforska möjligheten till att migrera till Function-as-a-Service. Bland annat har företag så som OpenFaaS hjälpt organisationer med att migrera till Function-as-a-Service-arkitektur genom att erbjuda orkestrering och verktyg för att övervaka applikationerna. Denna uppsatts syftar till att studera migreringsprocessen för en beteendedriven applikation byggd med Function-as-a-Service-arkitektur. Undersökningen kommer att fokusera på migreringsstrategi som använder Strangler Fig Pattern och kommer att analysera de faktorer som påverkar migreringsprocessen genom en litteraturstudie samt fallstudie. Resultaten av denna forskningsansats kan vara till hjälp för organisationer att bättre förstå möjligheten att använda beteendedriven utveckling för att utveckla Function-as-a-Service och möjligheten att migrera till Function-as-a-Service från en monolitisk arkitektur. Följaktligen kommer uppsatsen också att belysa de faktorer som påverkar migreringsprocessen från monolitisk till Function-as-a-Service genom att gå genom några av dess för- och nackdelar.

The optimal placement of virtual network functions (VNFs) improves the overall performance of servicefunction chains (SFCs) and decreases the operational costs formobile network operators. To cope with changes in demands,VNF instances may be added or removed dynamically, resourceallocations may be adjusted, and servers may be consolidated.To maintain an optimal placement of SFCs when conditionschange, SFC reconfiguration is required, including the migration of VNFs and the rerouting of service-flows. However, suchreconfigurations may lead to stress on the VNF infrastructure,which may cause service degradation. On the other hand, notchanging the placement may lead to suboptimal operation,and servers and links may become congested or underutilized,leading to high operational costs. In this paper, we investigatethe trade-off between the reconfiguration of SFCs and theoptimality of their new placement and service-flow routing. Wedevelop a multi-objective genetic algorithm that explores thePareto front by balancing the optimality of the new placementand the cost to achieve it. Our numerical evaluations show thata small number of reconfigurations can significantly reduce theoperational cost of the VNF infrastructure. In contrast, toomuch reconfiguration may not pay off due to high costs. Webelieve that our work provides an important tool that helpsnetwork providers to plan a good reconfiguration strategy fortheir service chains.

Despite the assessment of long-term niche dynamics could provide crucial information for investigating species responses to environmental changes, it is a poorly investigated topic in ecology. Here, we present a case study of multi-species niche analysis for 71 common breeding birds in Northern Italy, exploring long-term niche changes from 1992 to 2017 and their relationship with both population trends and species traits. We (i) quantified the realized Grinnellian niche in the environmental space, (ii) compared variations in niche breadth and centroid, (iii) tested niche divergence and conservatism through equivalency and similarity tests, (iv) calculated niche temporal overlap, expansion and unfilling indices, and (v) investigated their association with both population changes and species traits. Results supported niche divergence (equivalency test) for 32% of species, although two-thirds were not supported by the similarity test. We detected a general tendency to adjust the niche centroids towards warmer thermal conditions. Increasing populations were positively correlated with niche expansion, while negatively correlated with niche overlap, albeit at the limit of the significance threshold. We found moderate evidence for a non-random association between niche changes and species traits, especially for body size, clutch size, number of broods per year, inhabited landscape type, and migration strategy. We encourage studies correlating long-term population trends and niche changes with species traits’ information and a specific focus on cause-effect relationship at both the single and multiple-species level.

Despite the assessment of long-term niche dynamics could provide crucial information for investigating species responses to environmental changes, it is a poorly investigated topic in ecology. Here, we present a case study of multi-species niche analysis for 71 common breeding birds in Northern Italy, exploring long-term niche changes from 1992 to 2017 and their relationship with both population trends and species traits. We (i) quantified the realized Grinnellian niche in the environmental space, (ii) compared variations in niche breadth and centroid, (iii) tested niche divergence and conservatism through equivalency and similarity tests, (iv) calculated niche temporal overlap, expansion and unfilling indices, and (v) investigated their association with both population changes and species traits. Results supported niche divergence (equivalency test) for 32% of species, although two-thirds were not supported by the similarity test. We detected a general tendency to adjust the niche centroids towards warmer thermal conditions. Increasing populations were positively correlated with niche expansion, while negatively correlated with niche overlap, albeit at the limit of the significance threshold. We found moderate evidence for a non-random association between niche changes and species traits, especially for body size, clutch size, number of broods per year, inhabited landscape type, and migration strategy. We encourage studies correlating long-term population trends and niche changes with species traits’ information and a specific focus on cause-effect relationship at both the single and multiple-species level.

Many long-distance migratory bird species are in decline, of which environmental changes, such as climate change and land-use changes, are thought to be important drivers. The effects of environmental change on the migration of these birds have often been studied during spring migration. Fewer studies have explored the impacts of environmental change on autumn migration, especially at stopover sites. However, stopover sites are important, as the quality of these sites is expected to change over time. We investigated impacts of local environmental conditions on the migration strategy and body condition of the Pied Flycatcher (Ficedula hypoleuca) at an autumn migration stopover site using long-term ringing data (1996–2018) and local environmental conditions. We found that although the arrival and departure dates of birds at the stopover site remained unchanged, the body condition (fat score) of the individuals caught decreased, and the stopover duration increased. This suggests that conditions at the stopover site during the autumn migration period have deteriorated over time. This study emphasizes the importance of suitable stopover sites for migratory birds and stresses that changes in environmental conditions during the autumn migration period may be contributing to the current decline in long-distance migratory passerines.

Non-breeding movement strategies of migratory birds may be expected to be flexibly adjusted to the distribution and quality of habitat, but few studies compare movement strategies among populations using distinct migration routes and wintering areas. In our study, individual movement strategies of red-necked phalaropes (Phalaropus lobatus), a long-distance migratory wader which uses saline waters in the non-breeding period, were studied using light-level geolocators. Results revealed a migratory divide between two populations with distinct migration routes and wintering areas: one breeding in the north-eastern North Atlantic and migrating ca. 10,000 km oversea to the tropical eastern Pacific Ocean, and the other breeding in Fennoscandia and Russia migratingca. 6,000 km—largely over land—to the Arabian Sea (Indian Ocean). In line with our expectations, the transoceanic migration between the North Atlantic and the Pacific was associated with proportionately longer wings, a more even spread of stopovers in autumn and a higher migration speed in spring compared to the migration between Fennoscandian-Russian breeding grounds and the Arabian Sea. In the wintering period, van Bemmelen et al. Contrasting Movement Strategies in Phalaropes birds wintering in the Pacific were stationary in roughly a single area, whereas individuals wintering in the Arabian Sea moved extensively between different areas, reflecting differences in spatio-temporal variation in primary productivity between the two wintering areas. Our study is unique in showing how habitat distribution shapes movement strategies over the entire non-breeding period within a species.

This thesis focuses on the adaptive strategies of daphnids that allows them to maintain stable populations while deal with UV radiation, highlighting the differences in the responses that populations with different evolutionary histories may have.Although exposition to lethal doses in nature is unlikely, sub-lethal UV-B radiation doses may have strong impacts on zooplankton. This work initiates with a study aimed at determining the effect of sub-lethal doses UV-B radiation on filtration rates of two cladoceran species (Daphnia pulicaria and Ceriodaphnia dubia) and showed that filtration rates of D. pulicaria and C. dubia decreased by 50% and more than 80%, respectively, enhancing the importance of avoidance behaviour and recovery strategies for freshwater zooplankton species. This study was followed by a second one that assessed the ability of Daphnia pulex to develop tolerance to UV radiation, while disentangling, at the same time, the relative importance of local adaptations and ontogenetic processes behind such tolerance. Two populations from environments strongly differing in UV radiation conditions (Bolivian Andes and southern of Sweden) were UV-induced to produce photo-protective compounds and changes in behavioural responses that were monitored by 3D Nano-tracking. Although changes in tolerance capacity of both populations were evident in the results, differences between populations were more related to local evolution than to short-time ontogenetic processes, showing that tolerance to UV radiation is dependent on the evolutionary history of each species population.Such evolutionary differences should be reflected in the life-histories of both populations so that the next study, through structural equation modelling, shows clear differences in the life-history structures of both populations of Daphnia pulex. Main differences involve indirect effects of UV radiation on offspring production as well as the age at first reproduction. In addition to known toleranc

Background: Migrants have been hypothesised to use different migration strategies between seasons: a time-minimization strategy during their pre-breeding migration towards the breeding grounds and an energy-minimization strategy during their post-breeding migration towards the wintering grounds. Besides season, we propose body size as a key factor in shaping migratory behaviour. Specifically, given that body size is expected to correlate negatively with maximum migration speed and that large birds tend to use more time to complete their annual life-history events (such as moult, breeding and migration), we hypothesise that large-sized species are time stressed all year round. Consequently, large birds are not only likely to adopt a time-minimization strategy during pre-breeding migration, but also during post-breeding migration, to guarantee a timely arrival at both the non-breeding (i.e. wintering) and breeding grounds. Methods: We tested this idea using individual tracks across six long-distance migratory shorebird species (family Scolopacidae) along the East Asian-Australasian Flyway varying in size from 50 g to 750 g lean body mass. Migration performance was compared between pre- and post-breeding migration using four quantifiable migratory behaviours that serve to distinguish between a time- and energy-minimization strategy, including migration speed, number of staging sites, total migration distance and step length from one site to the next. Results: During pre- and post-breeding migration, the shorebirds generally covered similar distances, but they tended to migrate faster, used fewer staging sites, and tended to use longer step lengths during pre-breeding migration. These seasonal differences are consistent with the prediction that a time-minimization strategy is used during pre-breeding migration, whereas an energy-minimization strategy is used during post-breeding migration. However, there was also a

Tato bakalářská práce se zabývá tématem migrace žen pocházejících z Ruska, které již delší dobu žijí v České republice, konkrétně na území Pardubic. Na problematiku je nahlíženo též z hlediska genderu a určité diskriminace žen cizinek na pracovním trhu. V neposlední řadě se práce zabývá následnou integrací těchto žen do české společnosti. Teorie v této práce je vhodně doplněna zjištěnými fakty na základě výzkumu, který probíhal formou rozhovorů s informátorkami. Cílem práce je zjistit jejich tehdejší důvody a motivaci k migraci, jakou roli v tom hrály ony samy, a jakým způsobem probíhala jejich integrace v České republice., This thesis deals with the issue of migration of women from Russia, which has been living in the Czech Republic for a long time, specifically on the territory of Pardubice. At issue also is viewed from a gender perspective and a certain discrimination against women foreigners in the labor market. Finally, the work deals with the subsequent integration of these women into the Czech society. Theory in this work is suitably supplemented with facts determined on the basis of the research, which was conducted through interviews with the informants. The aim is to determine their reasons and motivations for migration, their role in this process, and how were their integration in the Czech Republic under way., Fakulta filozofická, Studentka reagovala adekvátním způsobem na připomínky oponenta i vedoucího práce.

[Aim]: To identify the migration routes and wintering grounds of the core populations of the near-threatened pallid harrier, Circus macrourus, and highlight conservation needs associated with these phases of the annual cycle. [Location]: Breeding area: north-central Kazakhstan; Wintering areas: Sahel belt (Burkina Faso to Ethiopia) and north-west India. [Methods]: We used ring recovery data from Kazakhstan and satellite tracking data from 2007 to 2008 on six adults breeding in north-central Kazakhstan to determine migration routes and locate wintering areas. In addition, one first-year male was tagged in winter 2007-2008 in India. [Results]: Data evidenced an intercontinental migratory divide within the core pallid harrier population, with birds wintering in either Africa or India. The six individuals tagged in north-central Kazakhstan followed a similar route (west of the Caspian Sea and Middle East) towards east Africa, before spreading along the Sahel belt to winter either in Sudan, Ethiopia, Niger or Burkina Faso. Spring migration followed a shorter, more direct route, with marked interindividual variation. The bird tagged in India spent the summer in central Kazakhstan. Half of the signal losses (either because of failure or bird mortality) occurred on the wintering areas and during migration. [Main conclusions]: Our study shows that birds from one breeding area may winter over a strikingly broad range within and across continents. The intercontinental migratory divide of pallid harriers suggests the coexistence of distinct migratory strategies within the core breeding population, a characteristic most likely shared by a number of threatened species in central Asia. Conservation strategies for species like the pallid harrier, therefore, require considering very large spatial scales with possibly area-specific conservation issues. We highlight urgent research priorities to effectively inform the conservation of these species.

Since user demand for a Video-on-demand (VoD) service varies with time in one-day period, provisioning self-owned servers for the peak load it must sustain a few hours per day leads to bandwidth underutilization at other times. Content clouds, e.g. Amazon CloudFront and Azure CDN, let VoD providers pay by bytes for bandwidth resources, potentially leading to cost savings even if the unit rate to rent a machine from a cloud provider is higher than the rate to own one. In this paper, based on long-term traces from two large-scale VoD systems and temporal development model of content clouds, we tackle challenges, design and potential benefits in migrating VoD services into the hybrid cloud-assisted deployment, where the user requests are partly served by the self-owned servers and partly served by the cloud. Our measurements show that the popularity of the most popular videos decays so quickly, for example, by 11% after one hour that it poses large challenges on updating videos in the cloud. However, the trace-driven evaluations show that our proposed migration strategies (active, reactive and smart strategies), although simply based on the current information, can make the hybrid cloud-assisted VoD deployment save up to 30% bandwidth expense compared with the Clients/Server mode. They can also handle unpredicted the flash crowd traffic with little cost. It also shows that the cloud price and server bandwidth chosen play the most important roles in saving cost, while the cloud storage size and cloud content update strategy play the key roles in the user experience improvement. © 2011 IEEE.

Since user demand for a Video-on-demand (VoD) service varies with time in one-day period, provisioning self-owned servers for the peak load it must sustain a few hours per day leads to bandwidth underutilization at other times. Content clouds, e.g. Amazon CloudFront and Azure CDN, let VoD providers pay by bytes for bandwidth resources, potentially leading to cost savings even if the unit rate to rent a machine from a cloud provider is higher than the rate to own one. In this paper, based on long-term traces from two large-scale VoD systems and temporal development model of content clouds, we tackle challenges, design and potential benefits in migrating VoD services into the hybrid cloud-assisted deployment, where the user requests are partly served by the self-owned servers and partly served by the cloud. Our measurements show that the popularity of the most popular videos decays so quickly, for example, by 11% after one hour that it poses large challenges on updating videos in the cloud. However, the trace-driven evaluations show that our proposed migration strategies (active, reactive and smart strategies), although simply based on the current information, can make the hybrid cloud-assisted VoD deployment save up to 30% bandwidth expense compared with the Clients/Server mode. They can also handle unpredicted the flash crowd traffic with little cost. It also shows that the cloud price and server bandwidth chosen play the most important roles in saving cost, while the cloud storage size and cloud content update strategy play the key roles in the user experience improvement. © 2011 IEEE.

Since user demand for a Video-on-demand (VoD) service varies with time in one-day period, provisioning self-owned servers for the peak load it must sustain a few hours per day leads to bandwidth underutilization at other times. Content clouds, e.g. Amazon CloudFront and Azure CDN, let VoD providers pay by bytes for bandwidth resources, potentially leading to cost savings even if the unit rate to rent a machine from a cloud provider is higher than the rate to own one. In this paper, based on long-term traces from two large-scale VoD systems and temporal development model of content clouds, we tackle challenges, design and potential benefits in migrating VoD services into the hybrid cloud-assisted deployment, where the user requests are partly served by the self-owned servers and partly served by the cloud. Our measurements show that the popularity of the most popular videos decays so quickly, for example, by 11% after one hour that it poses large challenges on updating videos in the cloud. However, the trace-driven evaluations show that our proposed migration strategies (active, reactive and smart strategies), although simply based on the current information, can make the hybrid cloud-assisted VoD deployment save up to 30% bandwidth expense compared with the Clients/Server mode. They can also handle unpredicted the flash crowd traffic with little cost. It also shows that the cloud price and server bandwidth chosen play the most important roles in saving cost, while the cloud storage size and cloud content update strategy play the key roles in the user experience improvement. © 2011 IEEE.

The software engineering discipline has been quite successful in creating various development models for constructing software systems. It has not however been that successful in creating later lifecycle process models. One of them concerns retirement. In this paper, we elicit a retirement process model and compare it to the current standard retirement process models. Our goal is to evaluate current retirement process standards and provide feedback for their extension. The elicitation process has been made within one Nordic financial company., QC 20110221