A three-dimensional, parallel, anisotropic, block-based, adaptive mesh refinement (AMR) algorithm is proposed and described for the solution of fluid flows on body-fitted, multi-block, hexahedral meshes. Refinement and de-refinement in any grid block computational direction, or combination of directions, allows the mesh to rapidly adapt to anisotropic flow features such as shocks, boundary layers, or flame fronts, common to complex flow physics. Anisotropic refinements and an efficient and highly scalable parallel implementation lead to a potential for significant reduction in computational cost as compared to a more typical isotropic approach. Unstructured root-block topology allows for greater flexibility in the treatment of complex geometries. The AMR algorithm is coupled with an upwind finite-volume scheme for the solution of the Euler equations governing inviscid, compressible, gaseous flow. Steady-state and time varying, three-dimensional, flow problems are investigated for various geometries, including the cubed-sphere mesh.

A three-dimensional, parallel, anisotropic, block-based, adaptive mesh refinement (AMR) algorithm is proposed and described for the solution of fluid flows on body-fitted, multi-block, hexahedral meshes. Refinement and de-refinement in any grid block computational direction, or combination of directions, allows the mesh to rapidly adapt to anisotropic flow features such as shocks, boundary layers, or flame fronts, common to complex flow physics. Anisotropic refinements and an efficient and highly scalable parallel implementation lead to a potential for significant reduction in computational cost as compared to a more typical isotropic approach. Unstructured root-block topology allows for greater flexibility in the treatment of complex geometries. The AMR algorithm is coupled with an upwind finite-volume scheme for the solution of the Euler equations governing inviscid, compressible, gaseous flow. Steady-state and time varying, three-dimensional, flow problems are investigated for various geometries, including the cubed-sphere mesh.

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In less than a century, programming languages have assumed many forms in adapting to system’s needs and capacities, of which our cognitive systems are a part. One variation, tailored specifically for the cognitive processes in children’s education of computational concepts, and nowadays successful among novice adult learners too, is that of visual block based programming. From the pool of available block based programming environments, Scratch is the most popular for users, and therefore becomes a good topic for researchers interested in contemporary educational discussions, including that of coding as a curricular activity in schools. Although inspired by the educational philosophy of using abstract physical blocks in foundational learning, the mainly visual interface of Scratch is made for keyboard and mouse mediated interaction with the digital content on-screen, producing audio-visual feedback. This research is a case study of Scratch, where the shortcomings found in interactions with its environment motivate the investigation of a potential hybrid technology – tangible and visual – for enhanced learning of foundational concepts in block based programming. The investigation is characterized by progressive cycles of conceptual design, supported by prototyping and testing. The results from its design process present the benefits and challenges of this hybrid concept to inform and inspire the development of new technologies for learning, as well as it should inspire designers of Tangible User Interfaces (TUIs) for learning and the educational community of computing to challenge the current ways of learning. The work here presented is concerned with acknowledging and building onto strengths of existing technologies, rather than substituting them with disruptive ideas.

Many learners find the transition from block-based programming to text-based programming difficult. Consequently, research has investigated how block-based languages support learners when making the transition to text-based programming. It categorized the way in which block-based languages support the transition into one-way transition, dual-modality and hybrid environments. This research investigates how one-way transition environments compare to dual-modality environments with regards to learning a text-based language, and how the two modalities differ with regards to the motivational factors satisfaction, enjoyment and easiness. The results show that dual-modality environments could be a better alternative than one-way transition environment when learners make the transition from block-based to text-based programming. The results also show that solving a problem in dual-modality environments could be easier than solving them in one-way transition environments, which could potentially mean that learners experience more motivation when making the transition in a dual-modality environment. This study also investigated if there is an alternative to one-way transition, dual-modality and hybrid environments when helping learners transition from block-based to text-based programming, and what a learning activity in this alternative solution could look like. It found that Blockly Games is an alternative, and describes a learning activity built in Blockly Games. Future research should aim at gaining a deeper understanding of the differences between one-way transition, dual-modality and hybrid environments, and investigate if the approach taken by Blockly Games is a better alternative. / Många elever tycker att övergången från blockbaserad programmering till textbaserad programmering är svår. Följaktligen har forskning undersökt hur blockbaserade språk stödjer elever när de gör övergången till textbaserad programmering. En studie fann att blockbaserade språk stöder denna övergång med hjälp av one-way transition miljöer, dual-modality miljöer och hybrid miljöer. Denna forskning undersöker hur one-way transition miljöer jämför sig med dual-modality miljöer när det kommer till att lära sig ett textbaserat språk, och hur de två modaliteterna skiljer sig åt med avseende på motivationsfaktorerna tillfredsställelse, njutning och lätthet. Resultaten visar att dual-modality miljöer kan vara ett bättre alternativ än one-way transition miljöer när eleverna gör övergången från blockbaserad till textbaserad programmering. Resultaten visar också att det kan vara lättare att lösa ett problem i dual-modality miljöer än att lösa dem i one-way transition miljöer, vilket potentiellt kan innebära att eleverna upplever mer motivation när de gör övergången i en dual-modality miljö. Denna studie undersökte också om det finns ett alternativ till one-way transition miljöer, dual-modality miljöer och hybrid miljöer när elever ska övergå från blockbaserad till textbaserad programmering, och hur en inlärningsaktivitet i denna alternativa lösning skulle kunna se ut. Den fann att Blockly Games är ett alternativ och beskriver en inlärningsaktivitet byggd i Blockly Games. Framtida forskning borde försöka få en djupare förståelse för skillnaderna mellan one-way transition miljöer, dual-modality miljöer och hybrid miljöer, och undersöka om det tillvägagångssätt som Blockly Games använder är ett bättre alternativ.

Blockbaserade utvecklingsmiljöer blir allt vanligare för att lära ut grunderna i programmering. Metoden har visat sig ha flera fördelar jämfört med textbaserad programmering, som historiskt sett varit den ledande metoden för undervisning. Då textbaserad programmering dominerar industrin i stort behöver övergången från block- till textbaserad programmering ske förr eller senare, för de som tänkt fortsätta inom området. Denna övergång har visat sig innebära flera utmaningar. Som en del av detta arbete togs en textbaserad utvecklingsmiljö fram, med inspiration från styrkorna i blockbaserade miljöer. Syftet med detta var att möjliggöra en jämförelse i läsbarhet av kod mellan de olika miljöerna, samt undersöka utfallet av att hämta inspiration från blockbaserade miljöer vid skapandet av en textbaserad miljö. Den nyutvecklade miljön är ett textbaserat alternativ till en befintlig blockbaserad utvecklingsmiljö, som används för att programmera en digital lekplats. Miljön utvärderas genom två tester. Det ena testet var ett läsbarhetstest som utfördes på en klass i årskurs sju, vars elever hade minimal tidigare erfarenhet av programmering. Det andra testet var ett användartest i utvecklingsmiljön, där åtta personer med tidigare erfarenhet av programmering fick utvärdera den textbaserade utvecklingsmiljön sett till hur nybörjarvänlig den var och hur väl designprinciperna var implementerade. Utvärderingarna visade att den utvecklade miljön ansågs vara nybörjarvänlig. Testerna visade även att miljön var mer läsbar än sin blockbaserade motsvarighet och överlag väl anpassad för nybörjare. Dessutom ansågs designprincipernas implementationer underlätta utveckling i miljön. / Block-based development environments are becoming increasingly common for teaching the basics of programming. This method has shown several advantages compared to text-based programming, which has historically been more popular for educational purposes. Since text-based programming dominates the industry, the transition from block-based to text-based programming is inevitable for those who plan to continue within the field. This transition implies several challenges. As a part of this study a text-based development environment was developed, taking inspiration from the advantages of block-based development environments. The purpose of this was to enable a comparison of code readability between the two development environments and to study the outcome of taking inspiration from the strengths of block-based programming environments. The developed text-based environment is an alternative to an existing block-based environment, used to program a digital playground. The environment was evaluated through two tests. One test was a readability test with a class of students in seventh grade, who had minimal previous programming experience. The other test was a user test, where eight people with previous experience of programming evaluated the text-based development environment in regard to how beginner-friendly it was and how well the design principles were implemented. The evaluations showed that the developed text-based environment was considered beginner-friendly. The tests also showed that the environment was more readable than its block-based counterpart and overall well-suited for beginners. In addition, the implementation of design principles was considered to facilitate development in the environment.