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The purpose of this paper is to derive a new lubrication model of double involute gears drive and study the effect of the tooth waist order parameters of double involute gears on lubrication performance.

The new lubrication model of double involute gears drive was established according to the meshing characteristics of double involute gears drive and the finite length line contact elastohydrodynamic lubrication theory. Numerical calculation of the lubrication model of gear drive was conducted using the multigrid method.

The results show that the oil film necking phenomenon and the oil film pressure peak emerged at the tooth waist order area and the tooth profile ends, and when compared with involute gear, the lubrication performance at the tooth waist order area is better than that at the tooth profile ends. The effect of tooth waist order parameters on lubrication performance at the tooth waist order area was greater than that at other areas.

This research will promote the application of the double involute gear as soon as possible, and it has the reference value for other types of gears.

This paper aims to better understand if speculative activity is a factor or even the main factor in the run-up of oil prices in the spot market, particularly in the recent price bubble that occurred in the period from mid-2003 to 2008.

The methodology used is based on an existing vector autoregressive model proposed by Kilian and Murphy (2014), which is a structural model of the global market for crude oil that accounts for flow demand and flow supply shocks and speculative demand oil shocks.

From the output of the authors’ structural model, the authors ruled out speculation as a factor of rising oil prices. The authors have found instead that the rapid oil demand caused by an unexpected increase in the global business cycle is the most accurate culprit. Despite the change of perspective in the speculative component, the authors’ conclusions concur with the findings of Kilian and Murphy (2014) and others.

As far as the authors are aware, this is the first time that a study has used as a spread oil variable, a speculative component of the real price, replacing the oil inventories considered by Kilian and Murphy (2014). Another contribution is that the model used allows estimating traditional oil demand elasticity in production and oil supply elasticity in spread movements, casting doubt on existing models with perfect price-inelastic output for crude oil.

The study aims to synthesise polyurethane dispersion from polyesteramide polyol. The polyesteramide polyol is a novel polyol for the synthesis of polyurethane dispersion.

Polyesteramide polyol has been synthesised from phthalic anhydride and fatty amide of mustard oil. Aminolysis of mustard oil had been carried out with diethanolamine. The novel polyurethane dispersion had been synthesised using a polyesteramide polyol as a precursor. Isophorone diisocyanate was used as an isocyanate component and polyurethane dispersion (PUDs) had been synthesised by an anionic method where DMPA was introduced to introduce –COOH groups as via grafting to the resin backbone. Triethylamine was used for neutralisation and, hence, for further dispersion in water. Hydroxyl ethyl methacrylate was used for the synthesis to introduce unsaturation in the backbone of PUDs. The coating was made by an UV curing process. The coating was characterised for mechanical properties, chemical properties, thermal properties as well as stain resistance.

The polyurethane dispersion formed through it has ester and amide linkage present in it. The acetone process is used for its synthesis. The nuclear magnetic resonance spectroscopy confirms the successful formation of polyesteramide polyol and PUDs. Even though long aliphatic chains present in polyol which may impart hydrophobicity the synthesis PUDs well dispersed in water. It is observed as the coating made from it have hardness and scratch resistance properties. The coating also exhibits good stain resistance properties.

The method is an easy one to synthesise polyurethane dispersion from polyesteramide polyol, which is based on ester and amide linkage.

To the best of the authors’ knowledge, this is the first report on synthesised polyurethane dispersion from polyesteramide polyol. The polyesteramide resin already proves its excellence and upcoming technology in the coating industry. Here, they are incorporated into the synthesis of polyurethane dispersion.

This paper sets out to argue that the strategic implementation of technology is implicated in a range of crises or socio‐economic disruptions, like peak oil, climate change and the rising environmental costs of energy consumption. It aims to argue that institutional technological implementation is contested, complex and should not be treated deterministically, but that technologists might usefully consider the impact of these disruptions on their practices. The paper seeks to amplify how a focus on resilience, rather than marketised outcomes, can enable higher education to use technology to overcome or adapt to disruption and crises.

The paper is a critique. A conceptual analysis of the place of current research into the use of technology‐enhanced learning in higher education is critiqued in light of peak oil and climate change, in order to align strategic developments with disruptions and potential responses. The strategic response of one institution is outlined as a programme‐of‐work, and is related to a second university's approach.

The paper highlights five areas that require strategic responses to the use of technology in and for HE. These are: the place of TEL in the idea of the University; complexity in the use of technology, linked to shared values; adapting to disruption; institutional planning; and competing priorities for the use of technology.

The paper highlights the educational connections that are made between the politics of technology, shared values and socio‐environmental disruption. It also analyses a programme of work that is designed to engage with and adapt to disruption.

This study aims to compare cavitation shapes between the simulating test rig and the engines to strengthen the findings that were first observed in the simplified experiments. Different forms of cavitation were identified, and their shape and size (length and width) were dictated from reciprocating speed and viscosity of the lubricant. Cavitation degrades performance in engineering applications and its effect is that it alters the oil film pressure.

Lubricant formulations were used for parametric study as well as different operating testing parameters in a simulating test rig and single cylinder engines with visualisation windows. An algorithm was used for extracting cavitation data from imaging, and comparison was made.

Similar phenomena at the simulating test rig and the engine were investigated and compared. The effect of different operating conditions was assessed along with the variations produced from the parametric lubricant study.

Engine results are limited due to manufacturing difficulties of visualisation windows and oil starvation. Firing tests are another difficult challenge as the modified section pressure is under more pressure and the window view is affected by combustion process. Limited pictures can be captured before cleaning is required. A lubricant manufacturer has to provide data regarding the chemistry of the lubricants.

The effect of cavitation in piston ring lubrication along with variable operating and lubricant parameters is further studied with quantification of cavitation results through image processing. These forms of cavities are affected by lubricant properties and operating conditions. A link between viscosity, cavitation, shear thinning properties, oil film thickness (OFT) and friction is given.

Coal, a fuel that once dominated the global energy scene, is staging a come‐back despite being environmentally dirty. The purpose of the paper is to analyse the return of King Coal to find out whether it is likely to be regain its dominance in the global energy in the future.

In analysing the metamorphosis of the coal industry, the paper looks at the historical evolution of the industry and analyses the factors behind the change. The deficiencies of coal's competitors are also analysed. Using a scenario analysis, the future role of coal in the global energy mix is estimated as well.

The paper finds that despite the domination of hydrocarbons in the global energy mix, coal has maintained a steady share and in some countries, it remained the main fuel. With the concerns of high‐oil prices and peak oil, coal is regaining its domination in the power sector around the world. The industry has reformed and restructured itself to remain competitive. Consequently, it has the possibility of staging a come back as a dominant fuel.

The paper is the first of its kind to take a long‐term perspective of the coal industry to analyse its re‐emergence as a dominant fuel. It combines the industry‐wide information to analyse the changes that swept the industry. It contributes by improving the academic understanding of a neglected fuel that still plays an important role.

The availability and price of oil are intimately linked to the global economy and as a result to tourism. This paper aims to present the results from research on tourism and oil, undertaken with a particular focus on New Zealand as a long‐haul destination in the light of dwindling global oil resources.

The findings of four distinct research phases will be reported in an integrative analysis.

The results highlight that economic prosperity in countries of origin, and in particular tourists' income, is of critical importance for outbound tourism, especially to long‐haul destinations. The econometric analysis of in‐country behaviour, such as consumption and regional dispersion, reveal that variables such as country of origin, travel purpose or length of stay are currently more important determinants of travel behaviour than fuel prices.

Coupled with differentiated oil vulnerabilities by different countries and different levels of price elasticity, the importance of market mix becomes evident. Tourism businesses can reduce their oil vulnerability by addressing a range of risk factors. Government policy and industry initiatives can support these micro‐economic adaptation processes.

Little research is available on the importance of oil shocks for tourism, and this paper is an attempt to address this gap. The findings are specific to New Zealand but will be of interest to other long‐haul destinations. The analysis integrates across a range of research methods.