Cement production which is one of the most energy intensive industries plays a significant role in emitting the greenhouse gases. Blended cement production by supplementary cementitious materials such as fly ash, ground granulated blast furnace slag and natural pozzolan is one of the smart approaches to decrease energy and ecology related concerns about the production. Fly ash has been used as a substance to produce blended cements for years, but bottom ash, its coarser counterpart, has not been utilized due to its lower pozzolanic properties. This thesis study aims to evaluate the laboratory performance of blended cements, which are produced both by fly ash and bottom ash. Fly ash and bottom ash obtained from Seyit&ouml / mer Power Plant were used to produce blended cements in 10, 20, 30 and 40% by mass as clinker replacement materials. One ordinary portland cement and eight blended cements were produced in the laboratory. Portland cement was ground 120 min to have a Blaine value of 3500&plusmn / 100 cm2/g. This duration was kept constant in the production of bottom ash cements. Fly ash cements were produced by blending of laboratory produced portland cement and fly ash. Then, 2, 7, 28 and 90 day compressive strengths, normal consistencies, soundness and time of settings of cements were determined. It was found that blended fly ash and bottom ash cements gave comparable strength results at 28 day curing age for 10% and 20% replacement. Properties of blended cements were observed to meet the requirements specified by Turkish and American standards.

Low-thrust spacecraft trajectory optimization is often a difficult and time-consuming process. One alternative is to instead use a closed-loop, feedback-driven control law, which calculates the control using knowledge of only the current state and target state, and does not require the solution of a nonlinear optimization problem or system of nonlinear equations. Though generally suboptimal, such control laws are attractive because of the ease and speed with which they may be implemented and used to calculate feasible low-thrust maneuvers. This thesis presents the theoretical foundations for seven modern low-thrust control laws based on control law "blending" and Lyapunov control theory for a particle spacecraft operating in an inverse-square gravitational field. The control laws are evaluated critically to determine those that present the best combinations of thoroughness of method and minimization of user input required. The three control laws judged to exhibit the most favorable characteristics are then compared quantitatively through three numerical simulations. The simulations demonstrate the effectiveness of feedback-driven control laws, but also reveal several situations in which the control laws may perform poorly or break down altogether due to either theoretical shortcomings or numerical difficulties. The causes and effects of these issues are explained, and methods of handling them are proposed, implemented, and evaluated. Various opportunities for further work in the area are also described. / text

In contemporary foreign language pedagogy, effective teaching of intercultural communicative competence cannot be separated from the use of technology. Web 2.0, social media, mobile devices, online and blended learning, and wearing technology have made it nearly impossible to develop effective courses without basing them on the target culture. Teaching culture, however, is not salient in foreign language teaching; it is the most neglected part (Sercu, 2005) and culture has to defend its legitimacy to be integrated in teaching languages, just as Kramsch (1995) put it "...culture, in order to be legitimate, has always had to justify itself" (p. 85). As a result, teachers devote around 20% of their teaching time to teaching culture (Castro, Sercu & García, 2004). In recent years, nevertheless, there has been a shift in understanding, implementing and integrating teaching culture in foreign language settings (Bayyurt, 2006, Chamberlin-Quinlisk, 2012; Gonen & Aglam, 2012; Castro, et. al., 2004; Byram, 2002), but at a slow pace (Castro et al., 2004; Sercu, García, & Castro, 2005). The situation of teaching culture using technology in Arabic is not as advanced as for other foreign languages and the attempts to remedy the problems are limited. Although interest in learning Arabic has noticeably increased in the last twenty years, educational institutions are far from ready to absorb the new enrollments. The lack of the integration of culture and technology in the Arabic teaching context has led to conducting three interrelated studies in this dissertation which investigated: teaching culture in Arabic: Teachers' and learners perspectives; teaching culture in Arabic: learners' perspectives on blended learning setting; and teaching culture in Arabic: Learners' affect of Arabic Hypermedia. The results of the three studies showed that the teachers and the learners understand the important role that culture plays, but statistically significant differences exist between teachers' and learners' views of some of the aspects of culture teaching. The results also show that learners had positive feelings towards the blended setting and the Arabic Hypermedia. Finally, in a call for teaching language as culture using technology, the dissertation suggests practical pedagogical implications for teaching foreign language and Arabic language.

An on-site simulation-based practice lab was conducted with 42 students enrolled in a blended distance practical nursing diploma program at the end of their first year of study, prior to their clinical placements. The six-hour practice lab involved an orientation, small group activities involving three obstetric-related scenarios using the moderate fidelity simulator Noelle®, and a debriefing activity. An evening social activity was also provided. The study used a mixed method research design involving both quantitative and qualitative methods. Data were collected using a demographic questionnaire, a 20-item pre-test/post-test knowledge quiz, and three National League for Nursing (NLN) instruments — the Simulation Design Scale, the Educational Practices in Simulation Scale, and the Learner Satisfaction and Self-Confidence in Learning Scale — as well as a pre- and post-lab administration of Rovai’s (2002b) Classroom Community Scale. The qualitative component of the study involved semi-structured interviews with 25 students, three lab facilitators, and five clinical placement instructors. Analysis of data collected before and after the simulation-based lab revealed a significant increase in knowledge and sense of community in the group as a whole. Analysis of the results of the NLN instruments indicated that the simulation-based practice lab was instructionally effective. Students were highly positive in their ratings of the design elements and implementation of the simulation-based practice lab, satisfied with the simulation-based learning activities, and confident in their ability to provide patient care. The qualitative analysis added a rich, descriptive understanding of how the simulation-based practice lab promoted instructional effectiveness (i.e., skills and knowledge, confidence, and learner satisfaction), preparation for clinical placement, and community cohesion. Thematic analysis of the interview data identified the following major themes: benefits to distance learners, nurse-patient interaction, theory to practice, positive experience, sense of community, and supportive learning (student interviews); benefits of simulation experience, facilitator role, and technology (facilitator interviews); and theory to practice, positive experience, and sense of community (clinical instructor interviews). This research supports the use of on-site simulation-based practice labs as a means to provide greater readiness for clinical practice and strengthen the sense of community among distance learners. / 2012-06

Darbe nagrinėjamas e.mokymosi elementų diegimas pradiniame ugdyme, pristatomas mišraus mokymosi modelis jaunesniojo amžiaus mokiniams. Pirmajame darbo skyriuje aptariama e.mokymosi bei mišraus mokymosi modelio samprata, analizuojama e.mokymosi priemonių pasiūla pradiniam ugdymui. Antrasis darbo skyrius skirtas tiriamajai veiklai apie e.mokymosi situaciją pradiniame ugdyme. Pateikiamos išvados bei rekomendacijos. Trečiajame skyriuje aprašoma projektinė dalis. Pristatomas suprojektuotas mišraus mokymosi aplinkos modelis pradinių klasių mokiniams, realizuota sąsaja tarp Impresio eJournal ir VMA Moodle. Tradicinėse pamokose naudojama elektroninė mokomoji medžiaga patalpinta eJournal aplinkoje, o savarankiškam mokinių mokymuisi pasirinkta VMA Moodle, nes ji yra atviro kodo plačiai taikoma Lietuvos švietimo įstaigose. Pristatomos schemos, diagramos, naudota programinė įranga e.mokymosi medžiagos rengimui. Paskutinė darbo dalis skirta mišraus mokymosi aplinkos vertinimui. Testavimo rezultatai parodė, jog aplinka pradinių klasių mokiniams suprojektuota tikslingai panaudojant e.mokymosi elementus, yra poreikis ją nuolat atnaujinti gerinant ugdymo kokybę. / This paper considers the implementation of elements of e-learning in primary education and introduces the model of blended learning for younger age of the students. The first chapter deals with the model concept of e-learning and blended learning, and with the analysis of e-learning tools’ supply for primary education. The second chapter covers the work of the research activity of the situation of e-learning in primary education. This chapter also involves conclusions and recommendations. The third chapter describes the designed part. It is introduced designed model of blended learning environment that is used for the students of primary education, also it is implemented an interface between Impresio eJournal and virtual learning environment Moodle. The e-learning material, which is used in traditional class, is hosted in eJournal environment, and it is chosen virtual learning environment Moodle for students’ self-learning because Moodle is open source system that is used widely in the educational institutions of Lithuania. This chapter also introduces charts and diagrams, and the software that is used for the preparation of the material. The last part is devoted to an assessment of the blended learning environment. The testing results showed that the environment is designed for the students’ of primary education by using the elements of e-learning purposeful, and also there is a need to upgrade it constantly in order to improve the quality of education.

Der Bericht beschreibt die Evaluation des Blended Learning-Angebots TASKtrain. Im Zentrum steht eine benutzerorientierte Analyse des E-Learning-Angebots TASKtrain (siehe https://bildungsportal.sachsen.de/opal/auth/RepositoryEntry/6838648833?sess=true). Das E-Learning-Angebot wurde gemeinsam vom Medienzentrum der TU Dresden und von der Professur für Allgemeine Pädagogik der Universität Leipzig im Projekt TASKtrain - Kompetenzorientierte Qualifizierung von Hochschullehrenden zur Konzeption und Erstellung von E-Prüfungsaufgaben entwickelt und erprobt (siehe http://tu-dresden.de/die_tu_dresden/zentrale_einrichtungen/mz/weiterbildungen_schulungen/tasktrain). Dieses Projekt wurde mit finanzieller Unterstützung des SMWK realisiert.

Communities of practice that occur naturally within an organisation enable the members to learn through participation in practice together (Lave & Wenger, 1991). However, when a community lacks expertise in 21st century practices, learning these skills through shared practice becomes difficult. E-learning is often marketed as if the tools were easy to adopt and adapt, but effective professional development is required to support educators in learning to employ e-learning tools in their practice. Research shows that effective professional development is timely, relevant, flexible, and often collaborative in nature with examples of good practice. The research presented in this thesis describes the design and implementation of professional development which supports a community of practitioners in building the expertise to incorporate e-learning within its professional practice. The research was informed by a comprehensive review of literature on professional development, with a focus on the area of e-learning, the theory behind the communities of practice concept, and the application of that theory. A design-based methodology was employed to gather data from a range of sources of evidence, over two years, in four iterative cycles of collaborative design, implementation, evaluation and redesign. The context in which the research took place was a small educational organisation with an average of twenty staff members over the duration of the study. This staged implementation of an online environment, designed in collaboration with the community, supported the development of a blended community of online practice and provided timely, relevant professional development in e-learning. Analysis of the research findings produced two instruments: (1) a matrix of strategies for enabling and supporting the development of a blended community of online practice, and (2) a heuristic model to guide the investigation of the learning taking place within the online aspect of a blended community of online practice. These instruments are recommended to designers, developers or researchers supporting the development of a blended community of online practice and the professional development taking place in its online environment.

ICT4D, here defined as the use of Information and Communication Technologies (ICT) in developing regions, can be seen as one of the most powerful and cost efficient ways to improve the standard of living in the developing world. Many regions in Asia have shown a rapid but heterogeneous development where information technology had a drastic impact on development but often with the problems related to ICT4D 1.0: lack of sustainability and lack of scalability. This study analysed the Sri Lankan infrastructure for region-wide dissemination of blended learning in the 21st century based on the exploration of some selected ICT4D hubs and educational initiatives. The overall aim of the research was to observe, describe and analyse how the selected ICT4D initiatives and the creation of ICT4D hubs in Sri Lanka might support region-wide dissemination of blended learning and local development. A longitudinal case study has been the overall approach where a number of embedded thematic units were explored in long-term fieldwork conducted between 2006 and 2012. Data has been collected from a combination of observations, interviews, group discussions, surveys and document analysis. Findings showed that several of the studied ICT4D hubs have contributed to the general development but the country’s internal digital divide has in fact grown, as urban growth has been so much faster than the growth in rural areas, leaving the country with geographic as well as socio-economic gaps. Some of the former war zones have definitely been left behind and there is a need for further support of the Eastern and Northern regions of the island. Sri Lanka has had an outcome that must be classified as better than average compared to other developing regions with increased opportunities for education and with some ICT4D hubs as multipurpose meeting points. Contributing factors to the successful development are the high literacy rate, the chain of ICT4D projects rolled out in the right order and a committed implementation of educational eServices. On the other hand there were other, more negative findings indicating that sustainability, knowledge sharing and inter-project cooperation and coordination have often failed. The identified strength in the Sri Lankan model, which can be recommended for other parts of the world as well, is the way top-down management of infrastructure sometimes is combined with bottom-up grass-root activities. Other recommendations, that also are global, are to extend existing ICT4D hubs and upgrade them to more intelligent, autonomous and multi-service ICT4D routers that could also handle the future need for eServices in the fields of eHealth, eFarming and eGovernance.

Radical aircraft and propulsion system architecture changes may be required to continue historic performance improvement rates as current civil aircraft and engine technologies mature. Significant fuel-burn savings are predicted to be achieved through the Distributed Propulsion concept, where an array of propulsors is distributed along the span of an aircraft to ingest boundary layer air and increase propulsive efficiency. Studies such as those by NASA predict large performance benefits when integrating Distributed Propulsion with the Blended Wing Body aircraft configuration, as this planform geometry is particularly suited to the ingestion of boundary layer air and the fans can be redesigned to reduce the detrimental distortion effects on performance. Additionally, a conventional aircraft with Distributed Propulsion has not been assessed in public domain literature and may also provide substantial benefits. A conceptual aircraft design code has been developed to enable the modelling of conventional and novel aircraft. A distributed fan tool has been developed to model fan performance, and a mathematical derivation was created and integrated with the fan tool to enable the boundary layer ingestion modelling. A tube & wing Distributed Propulsion aircraft with boundary layer ingestion has been compared with a current technology reference aircraft and an advanced turbofan aircraft of 2035 technology. The advanced tube & wing aircraft achieved a 27.5% fuel-burn reduction relative to the baseline aircraft and the Distributed Propulsion variant showed fuel efficiency gains of 4.1% relative to the advanced turbofan variant due to a reduced specific fuel consumption, produced through a reduction in distributed fan power requirement. The Blended Wing Body with Distributed Propulsion was compared with a turbofan variant reference aircraft and a 5.3% fuel-burn reduction was shown to be achievable through reduced core engine size and weight. The Distributed Propulsion system was shown to be particularly sensitive to inlet duct losses. Further investigation into the parametric sensitivity of the system revealed that duct loss could be mitigated by altering the mass flow and the percentage thrust produced by the distributed fans. Fuel-burn could be further reduced bydecreasing component weight and drag, through decreasing the fan and electrical system size to below that necessary for optimum power or specific fuel consumption.

Multilingualism is a reality in South African classrooms. The Constitution of South Africa (Act 108 of 1996) and the national language policy recognize language rights and aims at supporting, promoting and developing the official languages. However, despite the advantages of mother tongue education, English is often chosen as language of learning and teaching at the cost of the African official languages. This study proposes the accommodation and promotion of multilingualism through blended learning. Blended learning refers to the blending of traditional instruction methods, such as face-to-face instruction, with other forms of instruction such as online learning and teaching. Through a discussion of asynchronous and synchronous learning tools it was established that wikis would be used for this study. In terms of blended learning and learning theories the main emphasis in this study is on socio-constructivism as well as communal constructivism. The empirical research in this study focused on the establishment and testing of a conceptual model for the accommodation and promotion of multilingualism through blended learning in the subject IT. The research took the form of a sequential embedded mixed methods design. Both quantitative and qualitative approaches were used. A questionnaire was used with IT teachers to investigate the language and blended learning context. This was followed up with qualitative research in the form of interviews aimed at provincial and national experts in terms of the subject IT and e-learning. Based on the literature and these two investigations, a conceptual model was developed. The conceptual model’s effectiveness was tested through a quasi-experimental study. A questionnaire was also completed by the respondents at the schools after the completion of the study. Through the testing of the effectiveness of the conceptual model it was found that multilingualism could successfully be accommodated and promoted through this conceptual model. / Thesis (Ph.D. (Education))--North-West University, Vaal Triangle Campus, 2011