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Seekers who visit professional virtual communities (PVCs) are usually motivated by knowledge-seeking, which is a complex cognitive process. How do seekers search for knowledge, and how is their search linked to prior knowledge or PVC situation factors? From the cognitive process and interactional psychology perspectives, this study investigated the three-way interactions between seekers’ expertise, task complexity, and perceptions of PVC features (i.e. knowledge quality and system quality) on knowledge-seeking strategies and resultant outcomes.

A field experiment was conducted with 119 seekers in a PVC using a 2 × 2 factorial design of seekers’ expertise (i.e. expert versus novice) and task complexity (i.e. low versus high).

The study reveals three significant insights: (1) For a high-complexity task, experts adopt an ask-directed searching strategy compared to novices, whereas novices adopt a browsing strategy; (2) For a high-complexity task, experts who perceive a high system quality are more likely than novices to adopt an ask-directed searching strategy; and (3) Task completion time and task quality are associated with the adoption of ask-directed searching strategies, whereas knowledge seekers’ satisfaction is more associated with the adoption of browsing strategy.

We draw on the perspectives of cognitive process and interactional psychology to explore potential two- and three-way interactions of seekers’ expertise, task complexity, and PVC features on the adoption of knowledge-seeking strategies in a PVC context. Our findings provide deep insights into seekers’ behavior in a PVC, given the popularity of the search for knowledge in PVCs.

Polyvinyl chloride (PVC) in its many forms accounts for a large proportion of plastics production and packaging in Western Europe. Its applications and fitness for purpose as a food packaging are outlined, together with an analysis of the energy and materials required and by‐products made in its production. Methods of production are outlined, noting the environmental and health hazards. Problems associated with its disposal are described.

High‐impact PVC is ordinary, unplasticised PVC without the degree of brittleness which used to be associated with it. The physical and chemical properties of high‐impact PVC piping are outlined in this article, followed by a short section describing installation techniques. Market potentials in the water and chemical industries in particular are discussed.

Over the last few decades, the use of plastics as packaging materials has increased due to their properties and processibility. On the other hand, as a result of contact of packed food with plastics, traces of plastic components may migrate into the food medium contaminating it and affecting consumers’ health. This work concerns the study of migration of DINP and DOP plasticisers from PVC sheets into foodstuffs. PVC sheets using either type of plasticisers with different concentrations were prepared and then put in contact with different food simulants. Gravimetric analysis was used to determine the loss in plasticised PVC sheets upon immersion in food simulants. Changes in mechanical properties of tested sheets were observed. IR was used in the detection of plastic components in food simulants. A comparison was held between the migration of DINP and DOP plasticisers into food simulants.

PVC‐U replacement windows are being installed in domestic property across the developed world. It could be argued that this is a result of vigorous marketing, a need for energy conservation and possibly creative advertising. Citizens in Europe, the USA, even former Soviet countries are embracing this material as a suitable remedy for corroded mild steel and decayed timber original sash windows within residential properties. This paper seeks to try to quantify the phenomenon of PVC‐U replacement windows and also to explore the aesthetic effects of such replacements and argues that they constitute a permanent heritage loss to vernacular architecture in maturing towns and cities within the UK and examines the implications across Europe.

Because of their corrosion resistance, the ease with which they can be worked and their ready availability, PVC and polythene are now widely used in the construction of plant and equipment ranging from beakers and valves to large gas‐washing plants. Here the author discusses first the limitations of these materials and then describes how they are applied to fabricated structures and equipment, linings, coatings and cements. Brief mention is made of other modern plastics. This article is substantially the paper which the author gave at a symposium on the fabrication of PVC and polythene at the College of Technology, Birmingham, on April 8.

During the dispersion of a pigment in a given application medium, two main processes are taking place side by side. These are the wetting of the pigment surface by the binder components, and the actual dispersion process, i.e. the separation of agglomerates into primary particles or at least into smaller agglomerates by the application of mechanical energy.

The purpose of this paper is to investigate the interfacial nanostructures and the adhesions of the stainless steel (S.S) coating to the polyurethane (PU) and polyvinyl chloride (PVC) leathers.

PU leather and PVC leather deposit S.S nano-films on the surface of PU and PVC leathers in this study. The interfacial nanostructures were investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The experimental results revealed that the surface roughness of the substrates had extremely important influence on the morphology of nano-films. The adhesions of the S.S coating to the PU and PVC leathers were investigated by the peel-off test.

The results showed that the adhesive performance of the S.S nano-films coating on PVC leather was better than that on the substrate of PU leather. Moreover, a weight loss of per peeling force calculating formulation is proposed to determine the bonding strength between the S.S films and the substrates.

In this paper, influence of different substrates on surface morphology of S.S coating was studied by SEM and AFM. Moreover, the weight loss of per peeling force calculating formulation was used to discuss the bonding strength between the S.S coating and the substrates. The research methods presented in this paper are of innovation significance to a certain extent.

Bayesian cubature (BC) has emerged to be one of most competitive approach for estimating the multi-dimensional integral especially when the integrand is expensive to evaluate, and alternative acquisition functions, such as the Posterior Variance Contribution (PVC) function, have been developed for adaptive experiment design of the integration points. However, those sequential design strategies also prevent BC from being implemented in a parallel scheme. Therefore, this paper aims at developing a parallelized adaptive BC method to further improve the computational efficiency.

By theoretically examining the multimodal behavior of the PVC function, it is concluded that the multiple local maxima all have important contribution to the integration accuracy as can be selected as design points, providing a practical way for parallelization of the adaptive BC. Inspired by the above finding, four multimodal optimization algorithms, including one newly developed in this work, are then introduced for finding multiple local maxima of the PVC function in one run, and further for parallel implementation of the adaptive BC.

The superiority of the parallel schemes and the performance of the four multimodal optimization algorithms are then demonstrated and compared with the k-means clustering method by using two numerical benchmarks and two engineering examples.

Multimodal behavior of acquisition function for BC is comprehensively investigated. All the local maxima of the acquisition function contribute to adaptive BC accuracy. Parallelization of adaptive BC is realized with four multimodal optimization methods.

On the basis of earlier studies, an investigation is made into the function of inert and active pigments in anti‐rust paints. Satisfactory explanation of the pigment effect is shown to be impossible without due consideration of the surrounding medium and, if necessary, the substrate. The significance of metal soaps is their increase in the mechanical and chemical resistance of the dried film of binder. This, in turn, results in a reduction of water diffusion through the film in the case of a high PVC and, hence, in an increase in the anti‐corrosive effect.