The CIO role expectations instrument: validation and model testing

The validation of IS instruments has not been given the attention that it deserves. This study uses component-based structural equation modelling (PLS/SEM) to investigate the psychometric properties and possible modelling of the CIO role expectations instrument based on data obtained from 174 Australian CIOs. Results show that the CIO role expectation instrument has exhibited solid validity and reliability indices despite some minor weaknesses. The results also demonstrate the possibility to model the constructs of this instrument in different null and hierarchical models, and the validity of this instrument to measure the CIO role in different types of industries not just the healthcare sector in which it was developed. The results provide support for CIO role theory on two central issues: (1) CIOs are fulfilling a configuration of roles not just one specific role (2) the CIO roles can be grouped into two major categories: supply side roles and demand side roles

Note on a variation of the Schröder-Bernstein problem for fields

summary:In this note we study fields $F$ with the property that the simple transcendental extension $F(u)$ of $F$ is isomorphic to some subfield of $F$ but not isomorphic to $F$. Such a field provides one type of solution of the Schröder-Bernstein problem for fields

The near wall effect of synthetic jets in a boundary layer

Copyright @ 2007 Elsevier Inc. All rights reserved.An experimental investigation to analyse the qualitative near wall effect of synthetic jets in a laminar boundary layer has been undertaken for the purpose of identifying the types of vortical structures likely to have delayed separation on a 2D circular cylinder model described in this paper. In the first instance, dye visualisation of the synthetic jet was facilitated in conjunction with a stereoscopic imaging system to provide a unique quasi three-dimensional identification of the vortical structures. Secondly, the impact of synthetic jet structures along the wall was analysed using a thermochromic liquid crystal-based convective heat transfer sensing system in which, liquid crystals change colour in response to the thermal footprints of a passing flow structure. Of the different vortical structures produced as a result of varying actuator operating and freestream conditions, the footprints of hairpin vortices and stretched vortex rings revealed a marked similarity with the oil flow pattern of a vortex pair interacting with the separation line on the cylinder hence suggesting that either of these structures was responsible in delaying separation. Conditions were established for the formation of the different synthetic jet structures in non-dimensional parameter space

The use of friction stir welding for the production of Mokume Gane-Type materials

Mokume gane is a highly desirable and unique decorative material but production is difficult at both workshop and industrial levels. This paper describes a novel method for producing mixed metal, multi-colored, layered materials using friction stir welding (FSW) and compares the results with mokume gane made by a number of different conventional methods. FSW was invented in 1991 by TWI, a UK-based research and technology organization, and has found widespread use in the joining of aluminum and, more recently, steels. By adapting FSW it has been possible to successfully bond many layers of dissimilar metals such as silver, copper and brass, etc., while simultaneously producing unique patterns in the metal, minimizing further processing, reducing waste and potentially lowering costs. The technique avoids many of the problems experienced in workshop production, e.g., melting of lack of bonding, while allowing production of small, customized ingots and mass production of large sheets, with up to several square meters possible

Developing arts-based methods for exploring virtual reality technologies: A university–industry case study

Collaborations between human–computer interaction (HCI) researchers and arts practitioners frequently centre on the development of creative content using novel – often emergent – technologies. Concurrently, many of the techniques that HCI researchers use in evaluative participant-based research have their roots in the arts – such as sketching, writing, artefact prototyping and role play. In this reflective paper, we describe a recent collaboration between a group of HCI researchers and dramatists from the immersive theatre organization Kilter, who worked together to design a series of audience-based interventions to explore the ethics of virtual reality (VR) technology. Through a process of knowledge exchange, the collaboration provided the researchers with new techniques to explore, ideate and communicate their work, and provided the dramatists with a solid academic grounding in order to produce an accurate yet provocative piece of theatrically based design fiction. We describe the formation of this partnership between academia and creative industry, document our journey together, and share the lasting impact it has had upon both parties

An advanced numerical model of friction stir welding of DH36 steel

A numerical model of Friction Stir Welding (FSW) of DH36 steel plate (6mm thickness) has been developed using a CFD technique. Two welding speed conditions were used, a low welding speed of 200 RPM - 100mm/min, and a high welding speed of 550RPM- 400 mm/min. The heat generation, material flow and strain rate were calculated based on plastic deformation and frictional contact between the tool and workpiece. A CFD-based model has been produced to represent the asymmetry in temperature distribution between the advancing and retreating side, the material flow and the strain rate. The geometry of the model includes the tool plunged into the plate. The cooling system was also included in the simulation by calculating the heat flux lost for each part of the tool. The heat generated by viscous dissipation away from the tool was also taken into account. The total heat generated was divided into the individual tool parts (shoulder, probe side and probe end) and was found to be in good agreement with the experimental results for the areas affected by these parts. The maximum temperature obtained for the slow welding speed was 1012oC and for the high welding speed was 1250oC. Experimental metallographic examination has also been carried out on DH36 FSW steel plates to validate the CFD model. SEM analysis showed the formation of a fine microstructure of bainite, acicular ferrite and ferrite/cementite aggregate in the welded zone as compared to the ferrite/pearlite morphology in the base metal. It is found from the CFD and experimental results that the high speed welding conditions can produce defects such as wormholes and cracks in the welds associated with the probe side and probe end due to the lack of material flow especially on the advancing side. Tensile and fatigue testing were carried out for both slow and high welding speed samples, which broke outside the welded region in the tensile test, however, slow welding speed samples show more resistance to fatigue test and survived 644128 cycles, the high speed welding samples failed after 111,736 cycles under the same load

Modelling of friction stir welding of 304 stainless steel

A 3-D Eulerian steady-state CFD model has been developed to simulate the Friction Stir Welding (FSW) of 6mm plate 304 stainless steel (304SS). The Polycrystalline BoroNitride- Tungsten Rhenium (PCBN-WRe) hybrid tool was modelled with the workpiece in a fully sticking condition. The viscosity of stainless steel was calculated from the flow stress equation taken from a previous study of hot working carried out in a range of temperatures between 800oC-1200 oC and strain rates 0.001 s-1 to 5 s-1. The model predicted the temperature distribution in the Stirred Zone (SZ) for three welding cases including low, intermediate and high rotational speed/traverse speeds. The model also predicts that localised melting may occur if the tool rotational speed exceeds 400RPM. Finally, the model suggested a larger probe (12mm diameter at the shoulder base and 5.8mm length) with a stationary shoulder would prevent the localised melting and allow an increase in welding speeds without the associated introduction of stagnant zone related weld defects

Inadequacy of protein intake in older UK adults

The current dietary recommendation for protein intake in the UK is 0.75 g/kg/day, however, this population-wide recommendation does not necessarily reflect altered requirements for older adults to maintain muscle protein synthesis, nor does it encompass the potential impact of intake timing. Optimal muscle protein synthesis in older adults requires both higher intake requirements and a distribution of protein intake above a 25 g threshold, three times across the day. This study aimed to describe the protein intake of older adults in a UK region and compare the results to recommendations. The study re-assessed two existing datasets with rich diet information for older adults in the South Yorkshire area. Data were extracted from food diaries of 256 adults aged between 65 and 89 years old (mean ± SD 72.4 ± 5.3 years). Quantity and timing of intake were coded using Nutritics software and compared to recommendations. The relationship between body mass index (BMI), age, and protein intake was explored. Fewer than 50% of the participants met current UK recommendations (0.75 g/kg/day) and fewer than 15% met the ESPEN 1.2 g/kg/day age-specific recommendation. Only one participant met the 25 g/meal recommendation across three meals. These findings suggest that the older adult population is not achieving recommendations to maintain muscle protein synthesis. Nonetheless it identifies several straightforward opportunities for improvement, notably elevation of morning intake

A Holder Continuous Nowhere Improvable Function with Derivative Singular Distribution

We present a class of functions $\mathcal{K}$ in $C^0(\R)$ which is variant of the Knopp class of nowhere differentiable functions. We derive estimates which establish \mathcal{K} \sub C^{0,\al}(\R) for 0<\al<1 but no $K \in \mathcal{K}$ is pointwise anywhere improvable to C^{0,\be} for any \be>\al. In particular, all $K$'s are nowhere differentiable with derivatives singular distributions. $\mathcal{K}$ furnishes explicit realizations of the functional analytic result of Berezhnoi. Recently, the author and simulteously others laid the foundations of Vector-Valued Calculus of Variations in $L^\infty$ (Katzourakis), of $L^\infty$-Extremal Quasiconformal maps (Capogna and Raich, Katzourakis) and of Optimal Lipschitz Extensions of maps (Sheffield and Smart). The "Euler-Lagrange PDE" of Calculus of Variations in $L^\infty$ is the nonlinear nondivergence form Aronsson PDE with as special case the $\infty$-Laplacian. Using $\mathcal{K}$, we construct singular solutions for these PDEs. In the scalar case, we partially answered the open $C^1$ regularity problem of Viscosity Solutions to Aronsson's PDE (Katzourakis). In the vector case, the solutions can not be rigorously interpreted by existing PDE theories and justify our new theory of Contact solutions for fully nonlinear systems (Katzourakis). Validity of arguments of our new theory and failure of classical approaches both rely on the properties of $\mathcal{K}$.Comment: 5 figures, accepted to SeMA Journal (2012), to appea