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WebAssembly (WASM) is a binary instruction format for a stack-based virtual machine originally designed for the Web but also capable of being run on outside of the browser contexts. The WASM binary format is designed to be fast to transfer, load and execute. WASM programs are designed to be safe to execute by running them in a memory safe sandboxed environment. Combining dynamic linking with WebAssembly could allow the creation of adaptive modular applications that are cross-platform and sandboxed but still fast to execute and load. This thesis explores implementing dynamic linking in WebAssembly. Two artifacts are presented: a dynamic linking runtime prototype which exposes a POSIX-like host function interface for modules and an Android GUI interfacing prototype built on top of the runtime. In addition the results of measurements which were performed on both artefacts are presented. Dynamic linking does improve the memory usage and the startup time of applications when only some modules are needed. However if all modules are needed immediately then dynamic linked applications. perform worse than statically linked applications. Based on the results, dynamically linking WebAssembly modules could be a viable technology for PC and Android. The poor performance of A Raspberry Pi in the measurements indicates that dynamic linking might not be viable for resource contrained system especially if applications are performance critical.

Context. Software Product Line (SPL) is a set of software system products that have common features and product-specific features. Dynamic Software Product Line (DSPL) is an SPL that features runtime variability. Objective. The main objective of this study is to evaluate the latest research related to SPL dynamic variability in general. The second objective of this study is to investigate dynamic variability modeling methods and tools that are utilized and introduced for SPLs by the scholars. The third objective of this study is to investigate testing methods and tools that are utilized and introduced for DSPLs by the scholars. Method. The scientific research method of this study is Systematic Literature Review (SLR). Papers included are published between years 2015 and 2017. Four scientific digital libraries were used as data sources for the papers. Results. The main result of this study is that between years 2015 and 2017, there has been an active research community studying SPL dynamic variability. For all 25 papers included in this study, on a scale of 0 to 10, the arithmetic mean of the quality scores is 7.14 (median is 7.5). One industrial practice DSPL implementation case study was presented by the scholars. Three other case studies seemed to be more or less simplified exemplar of industry practice DSPL implementations. Two studies were focusing in testing aspects of DSPLs. The second result of this study is that scholars have utilized 19 existing dynamic variability modeling methods for SPLs, and introduced 17 new dynamic variability modeling methods for SPLs. Scholars have utilized seven existing dynamic variability modeling tools for SPLs, and introduced four new dynamic variability modeling tools for SPLs. The third result of this study is that scholars have introduced four new testing methods for DSPLs, and utilized two existing testing tools for DSPLs. Conclusions. The general conclusion of this study is that albeit SPL dynamic variability has been actively studied between years 2015 and 2017, there are still open research areas, especially in the field of industry practice use and testing of DSPLs. 2012 ACM Computing Classification System (CCS): Software and its engineering -> Software creation and management -> Software development techniques -> Reusability -> Software product lines Software and its engineering -> Software creation and management -> Designing software -> Software design engineering

Globally, there is a constant shortfall of financial resources in conservation, which has partially been supplemented by combining conservation and conservation-compatible businesses. Many protected and conserved areas in sub-Saharan Africa are largely funded by revenues generated within the area, mainly through ecotourism. While ecotourism revenues are bringing in money into the system, dependency on this single type of revenue source is making conservation areas – or even the whole protected area system – vulnerable to changes in visitor numbers, which are prone to different political or socio-economic disturbances (such as conflicts, economic recession, and epidemics). A sudden substantial decrease in revenues or increase in costs may threaten the existence, extent, and quality of conservation areas in terms of biodiversity conservation. Collecting and analysing economic information on protected and conserved areas can help investigate their long-term sustainability and resilience to financial threats, such as the COVID-19 pandemic and related economic outcomes. In this thesis, I assess how conservation costs and revenues vary between different types of protected and conserved areas, how financially self-sufficient they are, and how economically resilient these areas may be in the face of global changes. The analysis is based on financial data from different types of protected and conserved areas in South Africa: state-owned national parks (South African National Parks, later SANParks), provincial parks (Ezemvelo KwaZulu-Natal Wildlife, later Ezemvelo) and private conserved areas. With the use of simulation modelling and resilience theory, I discuss how potential economic resilience varies between protected areas. The findings indicate that there are significant differences in the cost-revenue structure of different kinds of protected and conserved areas, and especially between public and private. Ezemvelo receives most of its funds from the provincial government, whereas SANParks covers the majority of its costs from tourism revenues. Private game reserves again need to cover their costs independently. According to the findings, size is an important attribute to predict the per hectare net income and running costs of public protected areas but has no significant influence on those of private game reserves. For public protected areas, the running costs per hectare are significantly higher for protected areas less than 1000 hectares. Based on the economic modelling and resilience theory, I concluded that private game reserves are generally financially more viable, but their vulnerability lies in their lack of embeddedness within a larger system (e.g., a conservation organization) that could support them during difficult times and require and encourage a long-term commitment to conservation. The economic resilience of public protected areas is more closely tied to the political atmosphere regarding conservation funding: self-generated revenues form only a part of the budgets of public protected areas. In addition, protected areas which have large fixed costs and depend on high tourism revenues are likely to be less economically resilient. Because of the higher running costs and resultant sensitivity of net income to changes in costs and revenues, parks that are home to the “Big Five” species (lion, leopard, rhino, elephant and buffalo) are in a more vulnerable position in the face of disturbances, as the pandemic. To address the threats that upcoming socio-economic disturbances pose to the funding base of protected and conserved areas, more focus should be given to the economic resilience of these areas, especially in countries and occasions where the areas rely on self-generated revenues.

East Usambara Mountains situated in North-Eastern Tanzania, are globally recognized tropical forests that have a high biodiversity value. The Amani Nature Reserve encloses a high concentration of endemic species within versatile biodiversity. The aim of this study is to measure the ecotourism possibilities and potential of the Amani Nature Reserve and to provide sustainable areal development and livelihood option and outline the regional characteristic important in terms of ecotourism. The data for this study was gathered during a field trip in Tanzania, in January-March 2012, as part of an internship for WWF Finland, Coastal East Africa Initiative. The qualitative methods used included a structured questionnaire, semi-structured and in-depth interviews, field observation and literature analysis. Also, several discussions between different regional stakeholders were carried out. Six villages in the East Usambara Mountains are studied. The study concludes that the Amani Nature Reserve has high potential for ecotourism development and the area offers diverse nature related activities albeit the current visitor statistics are low. The overall results indicate the high value and possibilities with regional biodiversity, the locals' positive attitudes towards tourism but also the areal weaknesses; poor infrastructure, lack of facilities and services. The locals' willingness to cooperate and participate in ecotourism functions and existing cultural assets were also recognized. The Amani Nature Reserve's location, uniqueness and existing facilities strongly support the future ecotourism development. However the locals' knowledge on tourism impacts and conservation issues should be reinforced because there are currently multiple threats towards these tropical forests such as population growth and forest fragmentation. Ecotourism could reinforce forest conservation, local empowerment and sustainable livelihoods. In order to safeguard the ecotourism resource base, the environment, the ecotourism actions need to follow the ecotourism objectives and principles and consider different spatial environmental, social and economic characteristics. According to these principles the locals must be integrated in actions and decision-making processes at all levels and careful ecotourism planning, management and monitoring must take place. The ecotourism network development in Tanzania is highly possible because of the country's spectacular natural beauty and political stability. In order to safeguard the remaining life supporting wildlife also different stakeholders and locals should be engaged to work in cooperation seeking sustainable conservation means, such as ecotourism.

Nowadays the number of connected devices is growing sharply. Mobile phones and other IoT devices are inherent parts of everyday life and used everywhere. The amount of data generated by IoT devices and mobile phones is enormous, which causes network congestions. In turn, the usage of centralized cloud architecture increases delay and cause jitter. To address those issues the research community discussed the new trend of decentralization – edge computing. There are different edge compute architectures suggested by various researchers. Some are more popular and supported by global companies. Most of those architectures have similarities. In this research, we reviewed seven edge compute architectures. This thesis is a comparative analysis carried out by using key attributes and presentation of the Venn diagram to select the right edge compute architecture.

Parlamentaaristen aineistojen digitointi ja rakenteistaminen tutkimuskäyttöön on nouseva tutkimuksenala, jonka tiimoilta esimerkiksi Euroopassa on tällä hetkellä käynnissä useita kansallisia hankkeita. Tämä tutkielma on osa Semanttinen parlamentti -hanketta, jossa Suomen eduskunnan täysistuntojen puheenvuorot saatetaan ensimmäistä kertaa yhtenäiseksi, harmonisoiduksi aineistoksi koneluettavaan muotoon aina eduskunnan alusta vuodesta 1907 nykypäivään. Puheenvuorot ja niihin liittyvät runsaat kuvailutiedot on julkaistu kahtena versiona, parlamentaaristen aineistojen kuvaamiseen käytetyssä Parla-CLARIN XML -formaatissa sekä linkitetyn avoimen datan tietämysverkkona, joka kytkee aineiston osaksi laajempaa kansallista tietoinfrastruktuuria. Yhtenäinen puheenvuoroaineisto tarjoaa ennennäkemättömiä mahdollisuuksia tarkastella suomalaista parlamentarismia yli sadan vuoden ajalta monisyisesti ja automatisoidusti. Aineisto sisältää lähes miljoona erillistä puheenvuoroa ja linkittyy tiiviisti eduskunnan toimijoiden biografisiin tietoihin. Tässä tutkielmassa kuvataan puheenvuorojen esittämistä varten kehitetyt tietomallit ja puheenvuoroaineistojen keräys- ja muunnosprosessi sekä tarkastellaan prosessin ja syntyneen aineiston haasteita ja mahdollisuuksia. Toteutetun aineistojulkaisun hyödyllisyyden arvioimiseksi on Parla-CLARIN-muotoista aineistoa jo hyödynnetty poliittiseen kulttuuriin liittyvässä digitaalisten ihmistieteiden tutkimuksessa. Linkitetyn datan pohjalta on kehitetty semanttinen portaali, Parlamenttisampo, aineistojen julkaisemista ja tutkimista varten verkossa.

We will review techniques of perturbative thermal quantum chromodynamics (QCD) in the imaginary-time formalism (ITF). The Infrared (IR)-problems arising from the perturbative treatment of equilibrium thermodynamics of QCD and their phenomenological causes will be investigated in detail. We will also discuss the construction of two effective field theory (EFT) frameworks most often used in modern high precision calculations to overcome these. The EFTs are the dimensionally reduced theories EQCD and MQCD and Hard thermal loop effective theory (HTL). EQCD is three-dimensional Euclidean Yang-Mills theory coupled to an adjoint scalar field and MQCD is three-dimensional Euclidean pure Yang-Mills theory. The effective parameters in these theories are determined through matching calculations. HTL is based on resummation of hard thermal loops and uses effective propagators and vertex functions. We will also discuss the determination of the pressure of QCD perturbatively. In general, this thesis details calculations and the methodology.

The main purpose of this master's thesis is to present experiences of test automation in an industrial case, and to make recommendations of the best practices for the case. The recommendations are based on successful test automation stories found from the existing literature. The main issues that are hindering test automation seem to be similar in the case example and in the literature. The cost of implementation and maintenance combined with unrealistic expectations are perceived in almost every project. However, in the most successful projects, they have put a lot of effort to plan and implement maintainable sets of automatic tests. In conclusion, the evidence from the literature shows that successful test automation needs investments - especially in the beginning of the project. A few specific best practices are adapted to the case project, and presented in the form that they could be applied.

In Finland, the spent nuclear fuel will be deposited at a depth of 400 m in the granitic bedrock. The disposal is based on KBS-3 concept, which relies on the multi-barrier principle, where different successive barriers prevent the migration of radionuclides to biosphere. The spent nuclear fuel is placed in the disposal tunnels in copper-iron canisters, which are surrounded by bentonite clay to insulate them from the groundwater flow and protect from the movements of the bedrock. Bentonite clay consists mainly of montmorillonite, which like the other aluminosilicates are known to retain radionuclides thus, contributing to the retention or immobilization of them. Besides the contribution to the multi-barrier system, the bentonite buffer is assumed to be a potential source of colloids due to the erosion of bentonite in certain conditions. Colloids in the context of radionuclide migration are nanoparticles in the size range from 1 to 1000 nm that remain suspended in water. The montmorillonite colloids could potentially act as carriers for otherwise immobile radionuclides like transuranium elements in the case of canister failure. Especially, 241Am is an important radionuclide regarding the long-term safety of the final disposal as after a few hundred years 241Am and its mother 241Pu contribute most to the radiotoxicity of the spent nuclear fuel. The relevance of the colloids to the long-term performance is depending on several factors like colloid stability, mobility and their interaction with radionuclides. The colloid stability is depending on the groundwater conditions like ionic strength and pH. In low salinity groundwaters, the montmorillonite colloids have been shown to be stable. On the other hand, the collective processes of the rock matrix, bentonite colloids and radionuclides have to be investigated to assess the long-term performance of the multi-barrier system. It requires the combination of the different scale experiments from the simple laboratory experiments to large, natural scale in-situ experiments to understand the complex processes affecting the colloid-facilitated radionuclide migration. The large-scale laboratory experiments conducted with granite blocks offer an intermediate between the two extremes having a more natural system than the former and a better controllability than the latter. In this study, the radionuclide migration was studied in different scale laboratory experiments. The colloid-facilitated transport of Eu was studied with a block-scale experiment using a granite block with a natural water conducting fracture. The suitability of the block was assessed by conducting several experiments using different non-sorbing and sorbing tracer and montmorillonite colloids separated from synthetic Ni-labeled montmorillonite and Nanocor PGN Montmorillonite (98 %). Laser-induced breakdown detection (LIBD), photon correlation spectroscopy (PCS) and ICP-/MP-OES were utilized in colloid detection. Supportive batch experiments were conducted to study the colloid stability in different ground waters and the interaction between the granite, different montmorillonite colloids and Eu, an analog to Am. Good reproducibility was obtained with non-sorbing tracers. The breakthrough of the radioactive 3H, 36Cl and fluoresceine and Amino-G dyes showed similar behavior. On the other hand, no breakthrough of montmorillonite colloids or 152Eu occurred. Based on the literature review, the low flow rates used could be the reason for this. Low flow rate (50 μl/min) could affect the colloid mobility strongly which could explain that Eu retained in the fracture. More experiments with higher flow velocities would be required. Different montmorillonite materials showed similar but not exact the same sorption behavior of Eu. The fraction of Eu attached to colloids decreased during the experiments and correspondingly the fraction attached to the granite increased. At the same time, colloids remained stable during the expertiments. This indicates that desorption of Eu from the colloids is taking place in the presence of granite. Also, the effect of different water composition on the stability of colloids was clearly seen on the preparation of colloid suspensions in different water simulants. Even a small increase in the ionic strength of the solution made the especially Ni-montmorillonite colloids instable.

In Finland, the final disposal of spent nuclear fuel will start in the 2020s where spent nuclear fuel will be disposed 400-450 meters deep into the crystalline bedrock. Disposal will follow Swedish KBS-3 principle where spent nuclear fuel canisters will be protected by multiple barriers, which have been planned to prevent radionuclides´ migration to the surrounding biosphere. With multiple barriers, failure of one barrier will not endanger the isolation of spent nuclear fuel. Insoluble spent nuclear fuel will be stored in ironcopper canisters and placed in vertical tunnels within bedrock. Iron-copper canisters are surrounded with bentonite buffer to protect them from groundwater and from movements of the bedrock. MX-80 bentonite has been proposed to be used as a bentonite buffer in Finnish spent nuclear fuel repository. In a case of canister failure, bentonite buffer is expected to absorb and retain radionuclides originating from the spent nuclear fuel. If salinity of Olkiluoto island´s groundwater would decrease, chemical erosion of bentonite buffer could result in a generation of small particles called colloids. Under suitable conditions, these colloids could act as potential carriers for immobile radionuclides and transport them outside of facility area to the surrounding biosphere. Object of this thesis work was to study the effect of MX-80 bentonite colloids on radionuclide migration within two granitic drill core columns (VGN and KGG) by using two different radionuclides 134Cs and 85Sr. Batch type sorption and desorption experiments were conducted to gain information of sorption mechanisms of two radionuclides as well as of sorption competition between MX-80 bentonite colloids and crushed VGN rock. Colloids were characterized with scanning electron microscopy (SEM) and particle concentrations were determined with dynamic light scattering (DLS). Allard water mixed with MX-80 bentonite powder was used to imitate groundwater conditions of low salinity and colloids. Strontium´s breakthrough from VGN drill core column was found to be successful, whereas caesium did not breakthrough from VGN nor KGG columns. Caesium´s sorption showed more irreversible nature than strontium and was thus retained strongly within both columns. With both radionuclides, presence of colloids did not seem to enhance radionuclide´s migration notably. Breakthrough from columns was affected by both radionuclide properties and colloid filtration within tubes, stagnant pools and fractures. Experiments could be further complemented by conducting batch type sorption experiments with crushed KGG and by introducing new factors to column experiments. The experimental work was carried out at the Department of Chemistry, Radiochemistry in the University of Helsinki.