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We built this town: raising activity awareness through the workplace using gamification

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The wide adoption and continued advancement of information and communications technologies (ICT) have made it easier than ever for individuals and groups to stay connected over long distances. These advances

The wide adoption and continued advancement of information and communications technologies (ICT) have made it easier than ever for individuals and groups to stay connected over long distances. These advances have greatly contributed in dramatically changing the dynamics of the modern day workplace to the point where it is now commonplace to see large, distributed multidisciplinary teams working together on a daily basis. However, in this environment, motivating, understanding, and valuing the diverse contributions of individual workers in collaborative enterprises becomes challenging. To address these issues, this thesis presents the goals, design, and implementation of Taskville, a distributed workplace game played by teams on large, public displays. Taskville uses a city building metaphor to represent the completion of individual and group tasks within an organization. Promising results from two usability studies and two longitudinal studies at a multidisciplinary school demonstrate that Taskville supports personal reflection and improves team awareness through an engaging workplace activity.

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  • 2013

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Structural and photoelectrochemical characterization of gallium phosphide semiconductors modified with molecular cobalt catalysts

Description

The molecular modification of semiconductors has applications in energy

conversion and storage, including artificial photosynthesis. In nature, the active sites of

enzymes are typically earth-abundant metal centers and the protein provides a

The molecular modification of semiconductors has applications in energy

conversion and storage, including artificial photosynthesis. In nature, the active sites of

enzymes are typically earth-abundant metal centers and the protein provides a unique

three-dimensional environment for effecting catalytic transformations. Inspired by this

biological architecture, a synthetic methodology using surface-grafted polymers with

discrete chemical recognition sites for assembling human-engineered catalysts in three-dimensional

environments is presented. The use of polymeric coatings to interface cobalt-containing

catalysts with semiconductors for solar fuel production is introduced in

Chapter 1. The following three chapters demonstrate the versatility of this modular

approach to interface cobalt-containing catalysts with semiconductors for solar fuel

production. The catalyst-containing coatings are characterized through a suite of

spectroscopic techniques, including ellipsometry, grazing angle attenuated total reflection

Fourier transform infrared spectroscopy (GATR-FTIR) and x-ray photoelectron (XP)

spectroscopy. It is demonstrated that the polymeric interface can be varied to control the

surface chemistry and photoelectrochemical response of gallium phosphide (GaP) (100)

electrodes by using thin-film coatings comprising surface-immobilized pyridyl or

imidazole ligands to coordinate cobaloximes, known catalysts for hydrogen evolution.

The polymer grafting chemistry and subsequent cobaloxime attachment is applicable to

both the (111)A and (111)B crystal face of the gallium phosphide (GaP) semiconductor,

providing insights into the surface connectivity of the hard/soft matter interface and

demonstrating the applicability of the UV-induced immobilization of vinyl monomers to

a range of GaP crystal indices. Finally, thin-film polypyridine surface coatings provide a

molecular interface to assemble cobalt porphyrin catalysts for hydrogen evolution onto

GaP. In all constructs, photoelectrochemical measurements confirm the hybrid

photocathode uses solar energy to power reductive fuel-forming transformations in

aqueous solutions without the use of organic acids, sacrificial chemical reductants, or

electrochemical forward biasing.

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Created

Date Created
  • 2018

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Characterization of oxide thin films and interfaces using transmission electron microscopy

Description

Multifunctional oxide thin-films grown on silicon and several oxide substrates have been characterized using High Resolution (Scanning) Transmission Electron Microscopy (HRTEM), Energy-Dispersive X-ray Spectroscopy (EDX), and Electron Energy-Loss Spectroscopy (EELS).

Multifunctional oxide thin-films grown on silicon and several oxide substrates have been characterized using High Resolution (Scanning) Transmission Electron Microscopy (HRTEM), Energy-Dispersive X-ray Spectroscopy (EDX), and Electron Energy-Loss Spectroscopy (EELS). Oxide thin films grown on SrTiO3/Si pseudo-substrate showed the presence of amorphised SrTiO3 (STO) at the STO/Si interface. Oxide/oxide interfaces were observed to be atomically clean with very few defects.

Al-doped SrTiO3 thin films grown on Si were of high crystalline quality. The Ti/O ratio estimated from EELS line scans revealed that substitution of Ti by Al created associated O vacancies. The strength of the crystal field in STO was measured using EELS, and decreased by ~1.0 eV as Ti4+ was substituted by Al3+. The damping of O-K EELS peaks confirmed the rise in oxygen vacancies. For Co-substituted STO films grown on Si, the EDS and EELS spectra across samples showed Co doping was quite random. The substitution of Ti4+ with Co3+ or Co2+ created associated oxygen vacancies for charge balance. Presence of oxygen vacancies was also confirmed by shift of Ti-L EELS peaks towards lower energy by ~0.4 eV. The crystal-field strength decreased by ~0.6 eV as Ti4+ was partially substituted by Co3+ or Co2+.

Spinel Co3O4 thin films grown on MgAl2O4 (110) were observed to have excellent crystalline quality. The structure of the Co3O4/MgAl2O4 interface was determined using HRTEM and image simulations. It was found that MgAl2O4 substrate is terminated with Al and oxygen. Stacking faults and associated strain fields in spinel Co3O4 were found along [111], [001], and [113] using Geometrical Phase Analysis.

NbO2 films on STO (111) were observed to be tetragonal with lattice parameter of 13.8 Å and NbO films on LSAT (111) were observed to be cubic with lattice parameter of 4.26 Å. HRTEM showed formation of high quality NbOx films and excellent coherent interface. HRTEM of SrAl4 on LAO (001) confirmed an island growth mode. The SrAl4 islands were highly crystalline with excellent epitaxial registry with LAO. By comparing HRTEM images with image simulations, the interface structure was determined to consist of Sr-terminated SrAl4 (001) on AlO2-terminated LAO (001).

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Created

Date Created
  • 2015