In recent years many teachers and students have begun having good access to digital technology in their classrooms, and in the context of Sweden the majority of secondary schools are known as one-to-one schools, with students having their own computer or tablet. However, the mere presence of technology in the classroom is not a guarantee for improved teaching and learning. In fact, there is a challenge involved with integrating technology in the classroom and many teachers need support. Therefore, the aim of this thesis is to contribute to the knowledge about support for teachers integrating digital technology, especially a classroom response system (CRS), in the mathematics classroom. This is done by focusing on frameworks for CRS task design and technology integration. The thesis consists of two papers and a kappa. Both papers use data from a design research project including interventions in two cases. Paper I focuses on the development of design principles and task types for CRS tasks in a multiple-choice format aiming to engineer mathematical classroom discussions. The study generated three design principles, six task types, and 31 empirically evaluated tasks. The empirical evaluation shows that teachers consider the evaluated CRS tasks useful for engineering mathematical classroom discussions. Paper II focuses on exploring the potential of Ruthven’s (2009) SFCP framework as tool for analyzing empirical data in order to conceptualize and analyze teachers’ reasoning about critical aspects of technology integration in the mathematics classroom. The results show that the SFCP framework can be useful for capturing teachers’ reasoning about critical aspects of technology integration, but also that the framework does not capture teachers’ reasoning about students’ attitudes and behaviors. Therefore, the framework would benefit from taking into consideration students’ attitudes and behaviors, as these features are a challenge teachers need to deal with when integrating technology in the classroom. This thesis kappa, building on earlier research as well as the results and methods of its own papers, ends with an elaborated discussion on the challenges and support for teachers wanting to integrate CRS in their mathematics classroom. / Lärare och elever har idag god tillgång till digital teknik i klassrummen. I Sverige är numera majoriteten av högstadie- och gymnasieskolorna en-till-en skolor där alla elever har en egen dator eller surfplatta. Blotta närvaron av digital teknik i klassrummen är inte en garanti för förbättrad undervisning och ökat lärande. I själva verket så är det en utmaning att integrera digital teknik i klassrummet och många lärare behöver stöd för att lyckas med detta. Syftet med den här uppsatsen är att bidra till kunskap om stöd för lärare som integrerar digitala verktyg i matematikklassrummet. Detta görs dels genom att fokusera på ramverk för att konstruera matematikuppgifter till digitala responssystem och dels genom att undersöka ett ramverk för teknikintegrering i undervisningen. Uppsatsen består av två artiklar och en kappa. Båda artiklarna använder data från ett designforskningsprojekt bestående av interventioner i två separat fall. Artikel I fokuserar på utvecklingen av designprinciper och uppgiftstyper för flervalsuppgifter till digitala responssystem. Uppgifterna syftar till att initiera och fördjupa matematiska diskussioner i klassrummet. Studien genererade tre designprinciper, sex uppgiftstyper och 31 empiriskt utvärderade flervalsuppgifter som kan användas för att välja, värdera och konstruera uppgifter till responssystem. Den empiriska utvärderingen visar att lärarna anser att de testade uppgifterna och uppgiftstyperna är användbara för att initiera matematiska klassrumsdiskussioner. Artikel II fokuserar på att undersöka potentialen av Ruthvens (2009) ramverk ”Structuring Features of Classroom Practice” (SFCP), som ett analytiskt verktyg för att begreppsliggöra och analysera lärares resonemang om kritiska aspekter vid teknikintegrering i matematikklassrummet. Resultatet visar att ramverket är användbart för att fånga lärares resonemang om kritiska aspekter vid teknikintegrering i undervisningen, men också att ramverket inte fångade lärares resonemang om elevers attityder och uppförande. Studien föreslår att ramverket kan utvecklas och förbättras genom att även ta hänsyn till elevernas attityder och uppförande, eftersom detta är kritiska aspekter som lärare behöver hantera när de integrerar teknik i klassrummet. Med utgångspunkt från tidigare forskning och resultaten i artiklarna avslutas uppsatsens kappa med en utvecklad diskussion om utmaningar och stöd för lärare som integrerar digitala responssystem i matematikklassrummet.

Världen har blivit mer digital och människor blivit mer beroende av att teknik alltid finns nära tillhands. Verksamheter använder sig av informationssystem för att utföra uppgifter mer effektivt och mindre kostsamt. För att informationssystem ska underlätta för användaren måste dessa vara användbara. För att uppnå användbarhet har designprinciper skapats, dessa principer är riktlinjer eller direktiv för att uppnå en god design. När problematik uppstår för användare måste dessa användare ofta komma i kontakt med kunnig IT-personal. Kontakten mellan användare och IT-personal brukar ske via ärendehanteringssystem.  Syftet med studien var att utifrån användarens perspektiv identifiera vilka designprinciper som är viktigast för ett ärendehanteringssystem för att uppnå användbarhet. Studien var begränsad till att undersöka Nielsens 10 heuristiska designprinciper.  Studien utgick från en deduktiv ansats med en kvalitativ datainsamlingsmetod. Det utfördes intervjuer på ett fallföretag för att samla in åsikter från användare av ett ärendehanteringssystem. Bredd och variation användes som metod för urval då det var av intresse att informanterna hade olika förkunskaper. Syftet med den insamlade empirin var att komma fram till viktiga egenskaper för att uppnå användbarhet för ett ärendehanteringssystem. Med denna information gick det att undersöka hur väl designprinciper uppnår dessa egenskaper. Även användares åsikter kring specifika designprinciper undersöktes, vilket också kom att påverka resultatet.  Studiens resultat visade sig innebära fyra viktiga egenskaper som användarna ansåg bör uppfyllas för att uppnå användbarhet. Hittbarhet, navigerbarhet, informationsstruktur och enkelhet menar användarna bör uppnås. Vidare när designprinciper utvärderades framkom fem principer som användare ansåg vara viktigast, anknytning mellan systemet och verkligheten, flexibilitet och effektivitet av användning, användarkontroll och frihet, överensstämmelse och standard och att känna igen sig snarare än att minnas. Dessa principer var även de som ansågs uppnå egenskaperna för användbarhet på bästa vis. / The world has become more digital and people have become more dependent on that technology always is accessible. Businesses are using technology to perform tasks more efficient and less costly. For information systems to facilitate the user, the systems must be useful. To achieve usability, design principles have been created. These principles are guidelines or directives to achieve a good design. When problems arise for a user, these users often must get in touch with knowledgeable IT-staff. The contact between user and IT-staff usually occurs via case management systems. The purpose of the study was to identify design principles that from the user's perspective are the most important for a case management system to achieve usability. The study was limited to examining Nielsen's ten heuristic design principles. The study was based on a deductive approach with a qualitative data collection method. Interviews were conducted on a case business to collect the views of users of a case management system. Width and variation was the method used for the selection of informants as it was of interest that the informants had different previous knowledge. The purpose of the empirical data was to identify important characteristics to achieve usability for a case management system. With this information, it was then possible to examine how well the design principles achieve these characteristics. The study also examined the users’ opinions about specific design principles, which also contributed to the results. The result of the study included four characteristics which the users felt should be met to achieve usability. Findability, navigability, information structure and simplicity are the characteristics users thought should be met to achieve usability. Furthermore, when design principles were evaluated, four principles emerged that users considered to be the most important, link between system and reality, flexibility and efficiency of usage, user control and freedom, compliance and standard, and to recognize themselves rather than remembering. These principles were those who were considered to answer the usability characteristics best.

There are growing concerns about quality of education in schools in many countries, and education systems implement mechanisms like school inspection, an external education quality assurance measure, to evaluate their education. Realising that effective improvement of education quality may be achieved from within rather than from outside, many education systems are adopting School Self-Evaluation (SSE), an internal evaluation process, to evaluate quality of education. This study attempted to identify the characteristics of effective SSE frameworks in order to develop one for Zimbabwean primary schools. The study utilised exemplary frameworks as facilitators for introducing SSE practices in Zimbabwe and was guided by the following question: What are the characteristics of an effective SSE framework for improving classroom quality in Zimbabwean primary schools? The study espoused design research approach which aims to provide solutions to various education problems. The study comprised three phases, the preliminary phase which included a literature review and a needs analysis with the former aimed to gain insight into the efficacy of SSE in evaluating quality of education. The needs analysis sought to establish how education is evaluated in Zimbabwean primary schools. The second, the prototyping phase, involved developing and formatively evaluating various prototypes. The last phase, a semi-summative evaluation, involved field-testing and appraisal of the intervention. Interviews and questionnaires were used to collect data. Six design principles were generated with the main ones being to engage stakeholders in developing SSE frameworks, to agree on the need for SSE initiative and to define the quality indicators in context. The main characteristics of the SSE framework were that it should have a clear purpose, be context specific, and should focus on what is essential for education. The main conclusion of the study is that there are no clear policy guidelines for Zimbabwean primary schools, coupled with lack of SSE instruments, to engage in self-evaluation of quality of education and therefore, no meaningful SSE takes place. An SSE framework with procedural guidelines developed in this research appears to be relevant, feasible and is expected to be effective for use in Zimbabwean primary schools. Some recommendations were made in order to improve Zimbabwe‟s quality of education. / Thesis (PhD)--University of Pretoria, 2015. / Centre for Evaluation and Assessment (CEA) / University of Pretoria / Science, Mathematics and Technology Education / PhD / Unrestricted

Blockchains and Byzantine Fault Tolerance form the basis of decentralized currencies and ledgers, such as Bitcoin, Ripple, ZeroCash, and Ethereum. Several studies have focused on the currency aspects (e.g. authenticity, integrity, anonymity, and independence from central banks). In this thesis, we start by exploring to understand the security challenges and practical solutions for building simple payment networks. Then, we leverage such understanding in identifying the security challenges of more advanced and complex systems, in particular Futures Exchanges. The decentralization of a Futures Exchange poses new security challenges: i) the interplay between the security and economic viability, i.e. using the Price Discrimination Attack one can strategically force a trader out of the market when the trader's anonymity is broken; ii) the non-monotonic security behavior of an Exchange, i.e. an honest action may invalidate security evidence; and iii) the proportional burden requirement in the presence of high-frequency participants. Our goal is to enucleate the non-trivial design principles to resolve these challenges for building secure and distributed financial exchanges. We demonstrate the application of the distilled design principles by building a cryptographic reference for a futures exchange called FuturesMEX. We also simulate the performance of a FuturesMEX Proof-of-Concept with the Lean Hog market data obtained from the Thomson Reuters Ticks History DB. The results show that the obtained protocol is feasible for a low-frequency market such as Lean Hog. Furthermore, we investigate an extension of public markets, i.e. dark pools (private markets), in which the order book information is conditionally visible to some (financially) suitable parties. We propose a new cryptographic scheme called Witness Key Agreement that makes dark trading possible by probing prices and volumes based on committed financial information Finally, we evaluate the theoretical and practical performance of the new scheme; using a simulation of the dark pool data collected from the aggressive Bloomberg Tradebook, we obtain positive results.

As part of a push for renewal by radio and communications-based company Ericsson, the company launched a new brand identity called Brand 2.0 and began to construct the Ericsson Design System (EDS), a toolbox of digital design and development resources. The purpose of the EDS is to streamline and speed up the design and development process, help maintain consistency in design across products and improve communication between teams. This study aims to find potential areas for improvement of the EDS. To accomplish this, we compare the Ericsson Design System to the best practices of what makes an effective design system, as well as compare it to other companies’ publicly available design systems. To make this comparison, we performed an expert evaluation of the EDS and conducted interviews with Ericsson employees with experience with the design system to understand its strengths and weaknesses. The study found that the EDS is well suited for developers using the supported platform, but lacks some big-picture support for designers. System adoption would benefit from a push for political support within Ericsson. / Som del av en förnyelseprocess på kommunikationsföretaget Ericsson så lanserade företaget en ny varumärkesidentitet kallad Brand 2.0, och påbörjade konstruktionen av Ericsson Design System (EDS), en samling av digitala design- och utvecklingsresurser. EDS syfte är att understödja kommunikation, effektivisera design- och utvecklingsprocesser för mjukvaruprodukter, samt bidra till en mer konsekvent design mellan olika produkter inom bolaget.Denna studie utvärderar Ericsson Design System med syftet att finna förbättringsmöjligheter för systemet. För att uppfylla detta syfte gjordes en jämförelse med industribeprövad praxis för vad som gör ett effektivt designsystem, samt en jämförelse med designsystem från andra aktörer. För att göra denna jämförelse utfördes en expertanalys samt en intervjustudie som hämtade data från befintliga användare av Ericsson Design System. Studiens resultat visar att EDS är väl anpassat till att stödja utvecklare som använder den avsedda plattformen, men saknar visst stöd för designers, och att systemets användning skulle kunna breddas om det hade ett starkare strukturellt stöd i Ericssons internpolitik.

We are facing an energy crisis because of the limitation of the fossil fuel and the pollution caused by burning it. Clean energy technologies, such as fuel cells and metal-air batteries, are studied extensively because of this high efficiency and less pollution. Oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are essential in the process of energy storage and conversion, and noble metals (e.g. Pt) are needed to catalyze the critical chemical reactions in these devices. Functionalized carbon nanomaterials such as heteroatom-doped and molecule-adsorbed graphene can be used as metal-free catalysts to replace the expensive and scarce platinum-based catalysts for the energy storage and conversion. Traditionally, experimental studies on the catalytic performance of carbon nanomaterials have been conducted extensively, however, there is a lack of computational studies to guide the experiments for rapid search for the best catalysts. In addition, theoretical mechanism and the rational design principle towards ORR and OER also need to be fully understood. In this dissertation, density functional theory calculations are performed to calculate the thermodynamic and electrochemical properties of heteroatom-doped graphene and molecule-adsorbed graphene for ORR and OER. Gibb's free energy, overpotential, charge transfer and edge effect are evaluated. The charge transfer analysis show the positive charges on the graphene surface caused by the heteroatom, hetero-edges and the adsorbed organic molecules play an essential role in improving the electrochemical properties of the carbon nanomaterials. Based on the calculations, design principles are introduced to rationally design and predict the electrochemical properties of doped graphene and molecule-adsorbed graphene as metal-free catalysts for ORR and OER. An intrinsic descriptor is discovered for the first time, which can be used as a materials parameter for rational design of the metal-free catalysts with carbon nanomaterials for energy storage and conversion. The success of the design principle provides a better understanding of the mechanism behind ORR and OER and a screening approach for the best catalyst for energy storage and conversion.

The Digital Doorway (DD) is a non-standard computer system deployed to promote computer literacy amongst the underpriviledged communities in South Africa. Since its inception there has been no usability evaluation of the software installed on the DD. This study investigate the applicability of standard involved two cycles of design research phases to develop a set of multi-category heuristics for evaluating a selection of interfaces and applications installed on the DD. The heuristic evaluation method was found to be an appropriate method for the evaluating the usability of the software as well as the direct accessibility support provided on the DD. As a triangulation exercise the heuristic evaluation was complementary role of using a combination of evaluation methods. / Computing / M. Sc. (Information Systems)

In the twenty-first century, there are still many difficulties arise on software development. For example, the growing commercial demand variability, but the software maintainable level over time becoming less and less. We have to raise the importance of software design. Using good software design approachs to face the increasingly complex commercial demand. Therefore, this study analyzed the large-scale enterprise systems for the software design problems. Based on the theory of software design, software design methodology, software architecture, design pattern and design principle, this study introduce three software design approachs:"Flexible Integration Design", "Loosely Coupled Design", and "Parameter Table Design". Using the extensibility, flexibility, pluggability and reuseability to design system integration solutions: "Unified Accounting Rule Table" and "Unified Interface". This will help the large-scale enterprise systems for software development to increase quality and efficiency.

The Digital Doorway (DD) is a non-standard computer system deployed to promote computer literacy amongst the underpriviledged communities in South Africa. Since its inception there has been no usability evaluation of the software installed on the DD. This study investigate the applicability of standard involved two cycles of design research phases to develop a set of multi-category heuristics for evaluating a selection of interfaces and applications installed on the DD. The heuristic evaluation method was found to be an appropriate method for the evaluating the usability of the software as well as the direct accessibility support provided on the DD. As a triangulation exercise the heuristic evaluation was complementary role of using a combination of evaluation methods. / Computing / M. Sc. (Information Systems)

Dieser Beitrag beschreibt ein einfaches Vorgehen für das Sammeln, Dokumentieren und Strukturieren von unstrukturiertem, teilweise nur implizit vorhandenem Wissen über mögliche Konstruktionslösungen aus einem speziellen Anwendungsbereich. Dabei wird ein agiler, auf Wissensgraphen basierender Ansatz verfolgt. Kurzbeschreibungen von Konstruktionsprinzipien werden als Lösungsbausteine ungeordnet in einem digitalen Lösungsspeicher abgelegt und dann über Beziehungen miteinander verknüpft. Ergänzend werden Beziehungen der Bausteine zu Eigenschaften, Kategorien und weiteren Objekten definiert. Die Lösungsbausteine können in Umfang und Detaillierungsgrad variieren. Das Vorgehen unterscheidet sich vom tabellarischen Aufbau eines Konstruktionskatalogs, bei dem das zu dokumentierende Wissensgebiet komplett erschlossen und gemäß einem festen Ordnungsschema gegliedert sein muss. Die praktische Umsetzung des hier vorgestellten Vorgehens erfolgte in der Vorentwicklung für die Flugzeugstrukturkonstruktion, wo kontinuierlich neue Konstruktionslösungen erfunden und weiterentwickelt werden und eine digitale, einfach erstellbare und leicht erweiterbare Lösungssammlung als Nachschlagewerk und Inspirationsquelle benötigt wurde.