A human environmentalist approach to diffusion in ICT policies: A case study of the FOSS policy of the South African Government

Purpose – Through an evaluation of the information technology (IT) adoption and diffusion models and the free and/or open source policy of the South African Government, the underlying assumption is that the developmental divide between those with and those without access to technology is purely technical. This paper aims to illustrate that if Free and/or Open Source Software is to be used as a building block to bridge the “digital divide” a more social and environmental perspective, which embraces the philosophy behind the software, needs to complement the technical perspective. The human environmental model is presented as a useful alternative which, if embraced, can inform more holistic information and communication technology (ICT) policies. Design/methodology/approach – Through a review of diffusion of innovations models an alternative diffusion framework is described and applied to an interpretive open source case study in South Africa. Findings – Contemporary diffusion and innovation models are narrowly focused on IT as a purely technological linear phenomenon. This perspective also underlies many ICT policies. A more socio-technical adoption model can assist in providing amore holistic approach to ICTpolicy development. Originality/value – The application of a new innovation model, the human environmental model, to ICT policy provides a holistic framework in which the complexity of the innovation process can be reflected in policy. Such an approach to ICT policy formulation will assist with broadening the perspective of policy makers from IT as a technical solution to IT as part of a socio-technical solution and recognise the duality of the innovation process

Viking GC/MS mechanisms design and performance

The Viking Lander gas chromatograph/mass spectrometer will analyze pyrolyzed samples of the Martian surface for organic content. The surface-sample loader and pyrolyzer assembly (SSPLA) is described, along with the major problems encountered during design and testing. Three mechanisms were developed to implement the required SSLPA functions: (1) a soil loader that forces soil from a filled rotating funnel into each of three ovens located on a carriage, (2) a Geneva drive for rotating and precisely indexing the ovens to receive sample, and (3) a toggle-clamp mechanism for sealing the ovens by forcing circular double knife edges into gold sealing surfaces

Aligning national policy imperatives with internal information systems innovations: a case study of an open source enterprise content management system in the South African public sector

This paper addresses the question: Can changes in internal organisational practices be effectively aligned with contentious national policy imperatives? One of the authors followed the implementation process of an Open Source Enterprise Management System in the South African Public Sector. During this process change management was observed in relation to challenges and opportunities in the alignment of the internal organisational changes to the imperatives of the national Free and Open Source Software policy. Based on this reflection it is proposed that the alignment of the organisational environment, change management strategies and \u22technologies in practice\u22 is required to address many of the \u22common\u22 change management challenges. However, this approach does not assist in addressing the major challenge of attaining harmonious internal organisational changes which attempt to implement contentious national policy

Heparin and air filters reduce embolic events caused by intra-arterial cerebral angiography - A prospective, randomized trial

Background-Intra-arterial cerebral angiography is associated with a low risk for neurological complications, but clinically silent ischemic events after angiography have been seen in a substantial number of patients.Methods and Results-In a prospective study, diffusion-weighted magnetic resonance imaging (DW-MRI) before and after intra-arterial cerebral angiography and transcranial Doppler sonography during angiography were used to evaluate the frequency of cerebral embolism. One hundred fifty diagnostic cerebral angiographies were randomized into 50 procedures, each using conventional angiographic technique, or systemic heparin treatment throughout the procedure, or air filters between the catheter and both the contrast medium syringe and the catheter flushing. There was no neurological complication during or after angiography. Overall, DW-MRI revealed 26 new ischemic lesions in 17 patients (11%). In the control group, 11 patients showed a total of 18 lesions. In the heparin group, 3 patients showed a total of 4 lesions. In the air filter group, 3 patients exhibited a total of 4 lesions. The reduced incidence of ischemic events in the heparin and air filter groups compared with the control group was significantly different (P=0.002). Transcranial Doppler sonography demonstrated a large number of microembolic signals that was significantly lower in the air filter group compared with the heparin and control groups (P=0.01), which did not differ from each other.Conclusions-Air filters and heparin both reduce the incidence of silent ischemic events detected by DW-MRI after intra-arterial cerebral angiography and can potentially lower clinically overt ischemic complications. This may apply to any intra-arterial angiographic procedure

Inferring the Structure of Ordinary Differential Equations

Understanding physical phenomena oftentimes means understanding the underlying dynamical system that governs observational measurements. While accurate prediction can be achieved with black box systems, they often lack interpretability and are less amenable for further expert investigation. Alternatively, the dynamics can be analysed via symbolic regression. In this paper, we extend the approach by (Udrescu et al., 2020) called AIFeynman to the dynamic setting to perform symbolic regression on ODE systems based on observations from the resulting trajectories. We compare this extension to state-of-the-art approaches for symbolic regression empirically on several dynamical systems for which the ground truth equations of increasing complexity are available. Although the proposed approach performs best on this benchmark, we observed difficulties of all the compared symbolic regression approaches on more complex systems, such as Cart-Pole

Inferring the Structure of Ordinary Differential Equations

Understanding physical phenomena oftentimes means understanding the underlying dynamical system that governs observational measurements. While accurate prediction can be achieved with black box systems, they often lack interpretability and are less amenable for further expert investigation. Alternatively, the dynamics can be analysed via symbolic regression. In this paper, we extend the approach by (Udrescu et al., 2020) called AIFeynman to the dynamic setting to perform symbolic regression on ODE systems based on observations from the resulting trajectories. We compare this extension to state-of-the-art approaches for symbolic regression empirically on several dynamical systems for which the ground truth equations of increasing complexity are available. Although the proposed approach performs best on this benchmark, we observed difficulties of all the compared symbolic regression approaches on more complex systems, such as Cart-Pole

Causal dynamic modeling with Bayesian methods

Root cause analysis is essential in industrial settings. Counterfactual formulations from causal inference assess whether failures would occur under different conditions, enabling system improvements via hypothetical interventions. However, the hypothetical nature of counterfactual distributions makes them inherently ambiguous, which is particularly challenging in continuous settings. If the underlying system is dynamic, as it is typically the case in industrial processes, this increases complexity, particularly with regard to scalability. This work tackles three challenges: uncertainties in counterfactual estimation, root cause identification in dynamic systems, and unobserved variables. To address uncertainties, we propose a Bayesian approach for improved reliability. For automatic root cause identification from a single faulty observation, we present an auto-regressive model with sampling-based estimation. Additionally, we sketch deconfounding techniques for unobserved variables. These methods enhance counterfactual reasoning, enabling faster, more accurate root cause identification and simplifying quality control

Extent, timing and nature of retreat of the British-Irish Ice Sheet offshore of north-western Ireland during and following the Last Glacial Maximum

Abstract There has been a long history of research that has attempted to reconstruct the extent and dynamics of the British-Irish Ice Sheet (BIIS) during the last glacial cycle. Early reconstructions of ice extent in Ireland were based on terrestrial evidence, and advocated a relatively restricted ice sheet during the Last Glacial Maximum (LGM) that did not cover the whole of the island. More recent investigations from the continental shelf around Britain and Ireland reveal evidence for a much larger ice sheet, confluent with the Fennoscandian Ice Sheet in the North Sea and extending westwards onto the Atlantic continental shelf. However, offshore chronological control on the timing of ice sheet advance and retreat remain poor for many sectors of the continental shelf, particularly west and north-west of Ireland. This thesis brings together high-resolution multibeam swath bathymetry, sub-bottom proler data, and sedimentological, micropalaeontological and geochronological data, in order to reconstruct the extent, timing and dynamics of the last ice sheet in Donegal Bay and the adjoining north-western Irish continental shelf. This area is of interest due to its location adjacent to the North Atlantic and the Gulf Stream branch of the thermohaline circulation, making this sector of the BIIS sensitive to external forcing. The new data in this thesis show evidence for the extension of a grounded ice sheet to the shelf edge at or shortly after 26.3 cal ka BP, and thus during the LGM. Foraminiferal assemblages and lithofacies show that subsequent retreat took place in a glacimarine environment, and acoustic stratigraphic data show that the retreat was characterised by several still stands and re-advances, creating a series of arcuate moraines across the shelf. Chronological data constrain initial retreat from the shelf edge to before 24.8 cal ka BP, with formation of a large moraine at the mouth of Donegal Bay dated to between 20.2 and 17.9 cal ka BP. The results and interpretations presented in this thesis thereby offers a new interpretation of the extent, timing and nature of the north-western sector of the BIIS, offshore of Donegal Bay and across the adjacent continental shelf, during the LGM and the subsequent deglaciation

The Power of Metaphors in Directing ISD Teaching

Metaphors have a tremendous power to guide our actions. In Information Systems Development (ISD) certain metaphors like Software Engineering has guided our thinking concerning how we practice ISD and also how we teach ISD. The argument of this paper is that if we, as ISD teachers, expand our metaphors of ISD we will be able to think more creatively about how we can teach ISD