Being an Insider Researcher While Conducting Case Study Research

It is crucial for social researchers to clarify their researchers’ roles, especially for those utilizing qualitative methodology to make their research credible. The purpose of this paper is to examine the advantages and disadvantages of the researcher’s insider role, an instructor, occupied within case study research on the integration of Information and Communication Technologies (ICT) in the teaching-learning process at the School for the Handicapped (SfH) in Turkey. In this respect the author will demonstrate and discuss the advantages and disadvantages of being an insider-researcher considering the researcher’s role, determining the case, the aim and research questions of the study, issues of the research design, the collection and analysis of data, ethical issues and reporting the data. Each theme is discussed concerning the advantages and disadvantages of being an insider researcher. The researcher concluded that in order to conduct valid research a researcher must overcome some of the disadvantages with the help of several preventions. The results have been discussed in the light of related literature and the whole data

The role of brucite, ground granulated blastfurnace slag, and magnesium silicates in the carbonation and performance of MgO cements

This study focuses on the enhancement of the technical and environmental performance of MgO cements through the inclusion of brucite, GGBS, talc and serpentine as partial MgO substitutes in concrete blocks. The influence of these additives on the microstructure, hydration, carbonation, and mechanical performance of blocks cured under natural and elevated CO2 conditions is presented. An optimum replacement level was determined for each composition via unconfined compressive strength (UCS), scanning electron microscopy (SEM), x-ray diffraction (XRD), thermogravimetric analysis (TGA) and acid digestion. Mixes subjected to accelerated carbonation indicated up to 100% carbonation in 7 days. Results highlight the suitability of each additive in replacing MgO without compromising performance.This is the author accepted manuscript. The final version is available from Elsevier via http://dx.doi.org/10.1016/j.conbuildmat.2015.07.10

Monolithically Patterned Wide-Narrow-Wide All-Graphene Devices

We investigate theoretically the performance advantages of all-graphene nanoribbon field-effect transistors (GNRFETs) whose channel and source/drain (contact) regions are patterned monolithically from a two-dimensional single sheet of graphene. In our simulated devices, the source/drain and interconnect regions are composed of wide graphene nanoribbon (GNR) sections that are semimetallic, while the channel regions consist of narrow GNR sections that open semiconducting bandgaps. Our simulation employs a fully atomistic model of the device, contact and interfacial regions using tight-binding theory. The electronic structures are coupled with a self-consistent three-dimensional Poisson's equation to capture the nontrivial contact electrostatics, along with a quantum kinetic formulation of transport based on non-equilibrium Green's functions (NEGF). Although we only consider a specific device geometry, our results establish several general performance advantages of such monolithic devices (besides those related to fabrication and patterning), namely the improved electrostatics, suppressed short-channel effects, and Ohmic contacts at the narrow-to-wide interfaces.Comment: 9 pages, 11 figures, 2 table

Systematic ICT Integration Model for Hearing Impaired Youths

The panelists, each one of them are the faculty at the School for the Handicapped, the only higher education institution for hearing impaired students in Turkey, will describe and present the findings of their ongoing “action research” project based on the “Systematic ICT Integration Model” which essentially provides an easy-to-follow structure and most importantly requires teacher-designers to explicitly justify why the technology is used, and how to effectively incorporate the technology

Gesture bike: examining projection surfaces and turn signal systems for urban cycling

Interactive surfaces could be employed in urban environments to make people more aware of moving vehicles, showing drivers’ intention and the subsequent position of vehicles. To explore the usage of projections while cycling, we created a system that displays a map for navigation and signals cyclist intention. The first experiment compared the task of map navigation on a display projected on a road surface in front of the bicycle with a head-up-display (HUD) consisting of a projection on a windshield. The HUD system was considered safer and easier to use. In our second experiment, we used projected surfaces to implement concepts inspired by Gibson’s perception theory of driving that were combined with detection of conventional cycling gestures to signal and visualize turning intention. The comparison of our system with an off-the-shelf turn signal system showed that gesture input was easier to use. A web-based follow-up study based on the recording of the two signalling systems from the perspective of participants in traffic showed that with the gesture-projector system it was easier to understand and predict the cyclist intention

Enhancement of the wet carbonation of artificial recycled concrete aggregates in seawater

This study aimed to improve the carbonation efficiency and reduce processing time of recycled concrete aggregates (RCAs). Different liquid mediums were used for wet carbonation and compared with dry carbonation. Reaction kinetics, phase assemblage, microstructure and performance of RCAs and recycled aggregate concrete (RAC) prepared with carbonated RCAs were evaluated. RCAs carbonated under seawater for 10 min achieved >9 % reduction in water absorption and 3 % increase in density, which were more efficient than dry carbonated samples. Compressive strength of RAC prepared with 1-h seawater carbonated RCAs was significantly improved. Formation of ettringite and calcite under wet carbonation increased density and strength by contributing to solid volume, also leading to improved bond strength in interfacial transition zone in RAC. Seawater presents several advantages as a medium for wet carbonation due to its abundant availability, CO2 capture capacity and accelerated hydration and carbonation, thereby enabling rapid improvement of RCA's and resulting concrete formulations' performance

Characterisation of passive layer on steel immersed in MgO-SiO₂ binder suspension solution

MgO-SiO2 binders inherently have lower pH compared to Portland cement (PC), raising concerns about their suitability for structural applications involving steel reinforcement. To address this concern, this study investigated steel passivation in MgO-SiO2 binders in the presence of sodium hexametaphosphate (SHMP), which improves workability and increases pH. The combined effect of SHMP and alkali addition in MgO-SiO2 on steel passivation was also evaluated. Passive layer formation on steel was characterised with electrochemical impedance spectroscopy (EIS), Raman spectroscopy, low-kV backscattered electron (BSE) scanning and x-ray photoelectron spectroscopy (XPS). The obtained results demonstrated the formation of a protective passive layer on steel in the presence of SHMP, along with the absence of corrosion in mixes with SHMP or alkalis. Alkali addition also improved steel passivation in MgO-SiO2 systems. While the passive layer in the MgO-SiO2 system containing SHMP/alkalis was similar to those present in PC samples, differences in its composition and thickness were highlighted

Passivation of reinforcing steel in reactive MgO cement blended with Portland cement

Reactive MgO cement (RMC) has an ability to gain strength by carbonation. One of the main concerns in RMC systems is the potential corrosion of reinforcing steel in structural applications. This study evaluated the feasibility of replacing small proportions of RMC with Portland cement (PC) to promote the passivation of reinforcing steel. Reinforcing steels embedded in RMC with different proportions of PC were investigated by electrochemical measurements and microstructural analysis. Pore solutions extracted from these pastes were evaluated for their chemical compositions. Inclusion of ≥2% PC enabled the passivation of steel. Passive film forming in RMC-PC blends consisted of Fe3O4 and Mg(OH)2, which was thicker than those in pure PC mixes. The formation of passive film was mainly attributed to the increased pH of the pore solution, which reached over 12 in RMC mixes containing only 2% PC. These findings highlighted the potential of using RMC mixes in reinforced concrete applications.</p