The effects of friction reducing polymers on the operation of journal bearings

As rotating machines become larger, an increasing number of plain journal bearings operate in the turbulent regime. The addition of small amounts of high molecular weight polymers to the lubricant offers an attractive method of counteracting the increased power loss. This effect has previously been investigated for turbulent flow in pipes. Experiments are described on the operation of a four-inch diameter bearing lubricated with a very dilute, aqueous solution of poly(ethylene oxide).It is shown that the film extent in large clearance bearings is very dependent on the operating parameters, A numerical analysis based on the Reynolds equation indicates that a minimum dissipation principle can be used to explain the delay in the formation of a full width film. The transition to turbulence occurred at a Reynolds number of 2000. There was little evidence of Taylor vortices. The bearing friction was significantly affected by the angular momentum of the leakage flow. Very low concentrations of polymer were found to be effective in reducing the friction. Typically, 0.005% by weight causing a reduction of k5% at a Reynolds number of 3500, The bearing was also significantly stabilised against whirling, although the pressure distribution was unchanged. The polymer became ineffective after approximately twenty passes through the bearing. The degradation caused by shearing will probably be the factor limiting commercial exploitation of friction reduction in turbulent bearings

The evolution of futures in school education

School education seems to be mostly stuck in an outdated industrial era worldview, unable to sufficiently address the significance and increasing rapidity of changes to humanity that are upon us. An integrated forward-looking view should, now more than ever, be of central importance in how we educate. Yet there is little sign that - unlike corporations - school systems are recognising the true value of futures studies. A brief history of futures in school education shows the significant role played by the World Futures Studies Federation in its evolution to date. The article also introduces integral analysis as a way of opening up new possibilities to help school education develop due foresight and to more fully realise its potential as a prime facilitator in individual and cultural evolution

Sedimentological and tectono-stratigraphic characterisation of a shallow-marine reservoir, ‘Dona’ Field, offshore Niger Delta

The ‘Dona’ field is located in the shallow offshore Coastal Swamp depobelt, western Niger Delta. The field contains multiple, stacked shallow-marine reservoir intervals of Miocene to early Pliocene age in the Agbada Formation. The area surrounding the field is characterised by a series of synthetic, listric normal faults that strike north-northwest to south-southeast and dip southwest. These faults show stratigraphic thickening in their hangingwalls, indicating growth, and are associated with the development of rollover anticlines, which define the trap configuration of the ‘Dona’ field. Spatio-temporal variations in stratigraphic expansion indicate that growth faulting started in more landward (northeasterly) locations and migrated progressively basinward (southwestward). These variations are consistent with growth faulting due to gravity-induced shale diapirism, potentially driven by overall progradation of the Niger Delta. Core and wireline-logs from a representative reservoir interval contain a facies assemblage and stratigraphic architecture developed under a mixed-influence depositional process regime, which was dominated by wave processes but influenced by tidal processes. Wave-dominated shoreface deposits occur in a series of coarsening- and shallowing-upward parasequences that are laterally continuous over the reservoir but are locally erosionally truncated by fining-upward tidal channel-fill deposits. The mixed-influence process regime may reflect spatial variations in the dominance of wave, tide and fluvial processes, as in the modern Niger Delta, and/or temporal variations between a regressive, wave-dominated regime and a transgressive, tide-dominated regime. Sedimentological heterogeneities are present across a range of scales, and their distribution reflects the mixed-influence depositional process regime

Time-Varying Sliding Mode Control for ABS Control of an Electric Car

Controller design for the Anti-Lock Braking System (ABS) of a wheeled vehicle is a challenging task because of the complex and nonlinear nature of the tyre-road interaction. An efficient ABS controller should be capable of maintaining the wheel slip at an optimal value, which is suitable for the particular road conditions experienced at a given instant in time, preventing the wheel from locking while braking. Many controller designs in the literature track either an optimal slip which is assumed constant or are not supported by experimental validation or simulation testing with higher order models. This paper first presents an ABS system based on a conventional Sliding Mode Control (SMC). The performance of this controller is tested on an experimental vehicle. The results are compared with simulation results obtained with both a quarter car model and a full-car model built in the Matlab/Simulink environment. The performance of this controller is improved by effective state estimation using a Sliding Mode Differentiator (SMD) where the results are benchmarked with an implementation using an Extended Kalman Filter (EKF). The paper then presents a controller based on Time-Varying Sliding Mode Control (TV-SMC) which tracks an optimal slip trajectory

Impact of the buoyancy–viscous force balance on two-phase flow in layered porous media.

Motivated by geological carbon storage and hydrocarbon recovery, the effect of buoyancy and viscous forces on the displacement of one fluid by a second immiscible fluid, along parallel and dipping layers of contrasting permeability, is characterized using five independent dimensionless numbers and a dimensionless storage or recovery efficiency. Application of simple dimensionless models shows that increased longitudinal buoyancy effects increase storage efficiency by reducing the distance between the leading edges of the injected phase in each layer and decreasing the residual displaced phase saturation behind the leading edge of the displacing phase. Increased transverse buoyancy crossflow increases storage efficiency if it competes with permeability layering effects, but reduces storage efficiency otherwise. When both longitudinal and transverse buoyancy effects are varied simultaneously, a purely geometrical dip angle group defines whether changes in storage efficiency are dominated by changes in the longitudinal or transverse buoyancy effects. In the limit of buoyancy-segregated flow, we report an equivalent, unidimensional flow model which allows rapid prediction of storage efficiency. The model presented accounts for both dip and layering, thereby generalizing earlier work which accounted for each of these but not both together. We suggest that the predicted storage efficiency can be used to compare and rank geostatistical realizations, and complements earlier heterogeneity measures which are applicable in the viscous limit

Social inclusion: Context, theory and practice

This paper reviews the literature on social inclusion in Australia and provides an overview of the current situation regarding university/community engagement. Social inclusion is a contested term in both academic and policy literature entailing a range of interpretations. The paper will argue that there is a spectrum of ideological positions underlying theory, policy and practice. The broad theoretical construct put forward regards social inclusion in relation to areas (who is to be included?) and degrees (ideologies) of inclusion. Possible areas of inclusion are socio‐economic status, culture (including indigenous cultures), linguistic group, religion, geography (rural and remote/isolated), gender, sexual orientation, age (including youth and old age), physical and mental health/ability, and status with regard to unemployment, homelessness and incarceration. Degree of inclusion comprises a nested threefold schema incorporating a spectrum of ideologies involving—from narrowest to most encompassing—the neoliberal focus on access and economic factors, the social justice focus on community participation and the human potential focus on personal and collective empowerment stemming from positive psychology and critical/transformative pedagogies. Contemporary Australian social inclusion policy is related to UK policy. While policy rhetoric indicates a broad interpretation of social inclusion, concerns are raised that a dominant Economicist agenda favours corporate and national economic interests over social and psychological ones. Questions are also raised about the privileging of some areas of inclusion over others and the possibility that reductive interpretations of social inclusion are forms of cultural assimilation. Social inclusion in practice is addressed both in relation to degrees of inclusion and through case studies. The paper provides an overview of examples of social inclusion interventions, including a review of two initiatives of RMIT University and Victoria University focussing on industry/community partnerships. The paper concludes with some challenges and issues for further research on social inclusion including a proposed in-depth survey and consideration of literature on integrative phenomena such as ecological sustainability, and contextualisation of social inclusion within broader movements of global socio‐cultural change

Geostatistical Earth modeling of cyclic depositional facies and diagenesis

In siliciclastic and carbonate reservoirs, depositional facies are often described as being organized in cyclic successions that are overprinted by diagenesis. Most reservoir modeling workflows are not able to reproduce stochastically such patterns. Herein, a novel geostatistical method is developed to model depositional facies architectures that are rhythmic and cyclic, together with superimposed diagenetic facies. The method uses truncated Pluri-Gaussian random functions constrained by transiograms. Cyclicity is defined as an asymmetric ordering between facies, and its direction is given by a three-dimensional vector, called shift. This method is illustrated on two case studies. Outcrop data of the Triassic Latemar carbonate platform, northern Italy, are used to model shallowing-upward facies cycles in the vertical direction. A satellite image of the modern Bermuda platform interior is used to model facies cycles in the windward-to-leeward lateral direction. As depositional facies architectures are modeled using two Gaussian random functions, a third Gaussian random function is added to model diagenesis. Thereby, depositional and diagenetic facies can exhibit spatial asymmetric relationships. The method is applied in the Latemar carbonate platform that experiences syn-depositional dolomite formation. The method can also incorporate proportion curves to model non-stationary facies proportions. This is illustrated in Cretaceous shallow-marine sandstones and mudstones, Book Cliffs, Utah, for which cyclic facies and diagenetic patterns are constrained by embedded transition probabilities

Measured Sensitivity of the First Mark II Phased Array Feed on an ASKAP Antenna

This paper presents the measured sensitivity of CSIRO's first Mk. II phased array feed (PAF) on an ASKAP antenna. The Mk. II achieves a minimum system-temperature-over-efficiency $T_\mathrm{sys}/\eta$ of 78 K at 1.23 GHz and is 95 K or better from 835 MHz to 1.8 GHz. This PAF was designed for the Australian SKA Pathfinder telescope to demonstrate fast astronomical surveys with a wide field of view for the Square Kilometre Array (SKA).Comment: 5 pages, 2 figures, accepted for publication in Electromagnetics in Advanced applications (ICEAA), 2015 International Conference o

An overview of early investigational drugs for the treatment of human papilloma virus infection and associated dysplasia

Introduction: High-risk HPV (HR-HPV) related invasive cervical cancer (ICC) causes >270,000 deaths per annum world-wide with over 85% of these occurring in low-resource countries. Ablative and excisional treatment modalities are restricted for use with high-grade pre-cancerous cervical disease with HPV infection and low-grade dysplasia mostly managed by a watch-and-wait policy.Areas Covered: Various pharmacological approaches have been investigated as non-destructive alternatives for the treatment of HR-HPV infection and associated dysplasia. These are discussed dealing with efficacy, ease-of-use (physician or self-applied), systemic or locally applied, side-effects, cost and risks. The main focus is the perceived impact on current clinical practice of a self-applied, effective and safe pharmacological anti-HPV treatment.Expert opinion: Current prophylactic HPV vaccines are expensive, HPV type restricted and have little effect in already infected women. Therapeutic vaccines are under development but are also HPV type-restricted. At present, the developed nations use national cytology screening and surgical procedures to treat only women identified with HPV-related high-grade dysplastic disease. However, since HPV testing is rapidly replacing cytology as the test-of-choice, a suitable topically-applied and low-cost antiviral treatment could be an ideal solution for treatment of HPV infection per se with test-of-cure carried out by repeat HPV testing. Cytology would only then be necessary for women who remained HPV positive. Although of significant benefit in the developed countries, combining such a treatment with self-sampled HPV testing could revolutionise the management of this disease in the developing world which lack both the infrastructure and resources to establish national cytology screening programs