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This study describes how the copper deposition rate and the degree of copper coverage in the holes on printed circuit boards were investigated. The composition of the chemical copper solution was varied, and consequently the deposition parameters were changed. By using Taguchi methods, the level of significance of the process parameters was determined.

Sequential application of fractional factorial and response surface designs in the regression modelling and optimisation of a multi‐parameter type manufacturing process is presented. In particular, the coating thickness variation of an acid copper plating process was minimised with high bath acidity, high cathodic current density and large anode‐cathode separation. Statistically designed experiments are shown to be highly effective in studying the effects and interactions of the various process factors.

Forklift trucks are generally operated with frequent accelerations and stops, reverse and operations of load handling. This way of operation increases the energy losses and consequently the need for reduction of fuel consumption from forklift customers. This study aims to build a model to replicate the performance of forklifts during real operations and estimate fuel consumption without building a real prototype.

AVL Cruise has been used to simulate forklift powertrain and hydraulic circuit. The driving cycles used for this study were in accordance with the standard VDI 2198. Artificial neural networks (ANNs), trained by the results of AVL Cruise simulations, have been used to forecast the fuel consumption for a large set of possible driving cycles.

The comparison between simulated and experimental data verified that AVL Cruise model was able to simulate the performance of real forklifts, but the results were only valid for the specified driving cycle. The ANNs, trained by the results of AVL Cruise for a certain number of driving cycles, have been found effective to forecast the fuel consumption of a larger number of driving cycles following the prescriptions of the standard VDI 2198.

A new method based on ANN, trained by AVL Cruise simulation results, has been introduced to forecast the forklift fuel consumption, reducing the computational time and the cost of experimental tests.

The purpose of this paper is to study the inhibition of carbon steel corrosion under wet/dry conditions using electrochemical techniques.

Sodium dihydrogen orthophosphate, dicyclohexylamine nitrite and sodium benzoate were used as inhibitors in the investigation. Plain carbon steel specimens were treated with three different inhibitors for a set period of time. One group of the specimens was subjected to 60 wet/dry cycles whilst a second group was kept continuously immersed in distilled water during the same period. The corrosion rates of the specimens were determined by electrochemical methods at several intervals during corrosion.

The three inhibitors showed good performance during the whole 60 days of wet/dry cycling. Sodium dihydrogen orthophosphate was the best of the three, giving the lowest corrosion rates. However, during full immersion tests in distilled water, specimens that had been treated with dicyclohexylamine nitrite and sodium benzoate performed better than did those treated with sodium dihydrogen orthophosphate. Moreover, the corrosion rates were significantly higher in the case of wet/dry cycling due to differential aeration created through partial immersion, which was a consequence of the wet and dry cycling process.

This study showed the beneficial effect of inhibitors in slowing down the corrosion of steel. Furthermore, wet/dry cycling of steel samples in the laboratory produced corrosion rates that were comparable to those measured under actual outdoor conditions.

The purpose of this study was to evaluate the effectiveness of sodium dihydrogen orthophosphate as an inhibitor to slow down or prevent atmospheric corrosion of the local mild steel during storage in the Arabian Gulf region. In light of the results of some preliminary studies, sodium dihydrogen orthophosphate was selected for further evaluation against atmospheric corrosion of steel after it was applied at 10 mM concentration for 1 day at room temperature.

The purpose of this study was to investigate the performances of two inhibitors in controlling corrosion of steel products in industrial and marine atmosphere.

Corrosion rates were determined by weight loss measurements. At certain periods of atmospheric exposure, the (disc shape) specimens were retrieved and studied by scanning electron microscopy and energy-dispersive spectrometry surface analysis techniques.

Both inhibitors were effective against corrosion of steel in the early stages of the atmospheric exposure (for about two months). With further exposure to the atmosphere, their inhibition effectiveness deteriorated and was totally lost within four months. Analysis of the specimens before exposure showed that the inhibitor film was thin for both treatments, and the unexposed treated surface for both inhibitors appeared similar to the untreated unexposed specimen surface. Characterization of the specimens at different exposure periods showed fewer corrosion blisters on dicyclohexylamine nitrite- and sodium benzoate-treated surfaces than on untreated specimens.

The objective of this study was to characterize the surfaces of the steel products produced locally during their exposure to the industrial and marine atmosphere of the Arabian Gulf region after being treated by sodium benzoate and dicyclohexylamine nitrite in controlling the corrosion of local mild steel products. According to the literature review, this study is original and will add value to the studies of inhibition of steel corrosion under similar environments.

Engaging hundreds or thousands of employees in challenges that address specific business needs is a well established innovation model. Large-scale idea generation is a key element of such challenges, and we have observed that it has remarkably consistent statistical properties across every challenge, company, and industry. It bears a strong analogy to the “long tail” that Chris Anderson recognized in electronic retail of books and music and shares its enabling economics. We propose that idea generation is driven by universal positive feedback properties which account for its observed power law form, scale independence, and dynamics of growth. Simulation reproduces these properties and suggests further details and consequences. These robust observations have significant impact on strategies in collaborative innovation.

The weather in the Arabian Gulf region constitutes an environment that is corrosive to carbon steel. In the Gulf region, atmospheric corrosion is aggravated further by the high salinity of Gulf sea‐water. In addition, sulphur dioxide and deposits from combustion products tend to make the atmosphere in the Gulf region even more corrosive. Various inhibitors are reported in the literature that can help in the prevention of metal corrosion in aqueous environments. Among these, sodium dihydrogen orthophosphate, sodium benzoate, sodium nitrite and sodium nitrate were obtained and the effectiveness of certain corrosion inhibitors on carbon steel specimens was examined in a simulated atmospheric corrosion environment containing 2% NaCl and 1% Na₂SO₄ with various inhibitor concentrations. Test specimens were prepared from locally produced carbon steel reinforcing bars. It was found as a result of the test programme that treatment of the steel with 10 or 100mM sodium dihydrogen orthophosphate for one day at room temperature resulted in the best inhibition of corrosion. The results also demonstrated that inhibitors such as sodium benzoate and sodium nitrite were only similarly effective, as was sodium nitrate. Plans further study to examine the inhibition performance of sodium dihydrogen orthophosphate under actual atmospheric conditions.