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The design of vacuum calibrators for the cooling of complex PVC profiles is central to the production of high quality extrudates. One important parameter governing cooling efficiency is the heat transfer coefficient at the interface between the stainless steel calibrator and the PVC extrudate, whose value is often taken as constant regardless of the extrusion velocity and the applied pressure vacuum. In this paper, a method is proposed to evaluate the variation of the heat transfer coefficient over the entire calibrator length. The idea is to use temperature measurements together with heat transfer simulation to derive a heat transfer correlation that can be used in practical design cases.

This paper aims to synthesize new terpolymers by the emulsion polymerization technique composed of acrylamide-based polyurethane monomers (TPM and MPM) with different vinyl acetate copolymer systems, such as vinyl acetate/butyl acrylate (VAc/BA), vinyl acetate/ethylhexyl acrylate (VAc/2-EHA) and vinyl acetate/vinyl ester of versatic acid (VAc/VEOVA 10) systems. The performance of the prepared terpolymers as binders in emulsion coatings and textile industries was investigated and compared with the analogous commercial ones.

New waterborne polyurethane-vinyl ester-vinyl acetate terpolymers with high solid content and nano-scale emulsions have been successfully synthesized in two steps. The polyurethane oligomers were prepared by the prepolymer method as the first step. The second step involved polymerization with different vinyl monomers. The synthesized terpolymers were characterized using FTIR, scanning electron microscope, thermogravimetric analysis, minimum film forming temperature and particle size analyzer methods.

The synthesized emulsion terpolymers have shown small particle sizes averaged of 70 nm and a narrow distribution range, along with good mechanical, thermal and chemical stabilities. The surface coating layers of the terpolymers also have some important in terms of smoothness, clarity and binding ability in water-based coating for up to 4425 scrub cycles at 30 GU. Further, a high potential application textile printing was achieved at high solid content of 47–50%.

The effects of different isocyanates and vinyl monomers on the properties of obtained emulsion coatings have been studied. The improvement consequences of the coating evaluation of the waterborne binders for emulsion paints have been described. The properties of polyester/cotton fabric print pigment printing of textiles appear to be most promising enhancements by using the prepared nanocomposites of PU-co-vinyl acetate-co-vinyl ester as waterborne binders. So that the prepared emulsions have the potential to replace solvent-based coatings as waterborne binders for both emulsion coating and textile printing applications.

There are three purposes in this paper: to verify the importance of bi-directional fluid-structure interaction algorithm for centrifugal impeller designs; to study the relationship between the flow inside the impeller and the vibration of the blade; study the influence of material properties on flow field and vibration of centrifugal blades.

First, a bi-directional fluid-structure coupling finite element numerical model of the supersonic semi-open centrifugal impeller is established based on the Workbench platform. Then, the calculation results of impeller polytropic efficiency and stage total pressure ratio are compared with the experimental results from the available literature. Finally, the flow field and vibrational characteristics of 17-4PH (PHB), aluminum alloy (AAL) and carbon fiber-reinforced plastic (CFP) blades are compared under different operating conditions.

The results show that the flow fields performance and blade vibration influence each other. The flow fields performance and vibration resistance of CFP blades are higher than those of 17-4PH (PHB) and aluminum alloy (AAL) blades. At the design speed, compared with the PHB blades and AAL blades, the CFP blades deformation is reduced by 34.5% and 9%, the stress is reduced by 69.6% and 20% and the impeller pressure ratio is increased by 0.8% and 0.14%, respectively.

The importance of fluid-structure interaction to the aerodynamic and structural design of centrifugal impeller is revealed, and the superiority over composite materials in the application of centrifugal impeller is verified.

Thinking and research in respect of accounting and finance over the past three decades have been dominated by a methodology that is primarily based on the predictability of accounting data and its relationship to certain phenomena. The magnitude of change in business makes the future unpredictable. Analysts and managers are confronting an entirely new business environment in which traditional approaches are no longer valid. A systems approach provides a new way of looking at financial analysis. The purpose of this study is to focus on the present, on the ability to cope and the capacity to change in a changing environment. The ability to create an own future is being seen as more important than the art of predicting the future. This paper describes an empirically tested dynamic balance model to establish whether entities are able to adapt, survive and prosper.

Flexibility has become a matter of survival for many organisations as we embark on the twenty‐first century. In the real estate field, flexibility has historically meant some combination of different forms of procuring, planning, constructing and financing space. This paper argues that such approaches are necessary, but not sufficient. Senior managers need more robust adaptive strategies that exploit knowledge management tools to model, under conditions of uncertainty, the real estate and human resource implications of different workplace decisions. These facets of workplace strategies are the knowledge infrastructure that enables agile organisations to cope successfully with chronic uncertainty.

The purpose of this paper is to provide insights into the overarching role of learning capabilities by presenting a framework to describe how learning capability development is captured by combining the three main elements of internal marketing orientation, exploratory capabilities and resource recombination.

This is a conceptual paper building upon the theoretical integration approach of Mayer and Sparrowe (2013) to establish competitive empowerment through learning capability development, effective internal response and resources recombination.

The competitive learning capability model provides a firm’s foundation for theorizing organizational competitive models from an internal perspective, by mastering learning capability development at the centre of the model.

The paper emphasizes the competitive connotation of learning capabilities as a construct in strategic management. It shows the underlying role of learning across organizational processes; hence, its theoretical significance through the learning capabilities model.

This paper argues that learning is at the centre of organizational competitiveness. Firms can achieve more fruitful results by continuously implementing resource integration strategies built on their learned experiences.

The principal significance of this paper lies in the achievement of conceptualizing learning from a strategic management perspective. Insight in this area helps bridge organizational efforts in pursuit of competitive advantage by exploiting key core learning competencies embedded in a firm’s resources and capabilities.

This paper seeks to investigate the influence of the external environment on the choice of strategic management activities, from a chaos and complexity perspective, since a business environment is a complex adaptive system.

The study in this paper was of an exploratory nature, using the qualitative techniques of case study, depth interviews and document analysis to collect data from two companies each in the IT and packaging industries, namely, more successful/less successful companies.

The paper finds that first, it was proposed that more successful companies in turbulent environments would use radical, fast and disruptive strategies. Furthermore, strategy making should be a democratic, bottom‐up process and should be organic, self‐organising, adaptive and emergent. The results confirmed these propositions. Second, it was proposed that more successful companies in stable environments would use more traditional management and strategies and more formal strategy planning activities. The findings did not confirm this proposition, probably due to the fact that in reality a truly stable environment does not exist in South Africa.

This paper is of benefit to managers and strategists by emphasising a new way to consider the future management and strategies of their companies. Since businesses and markets are complex adaptive systems, using complexity theory to increase understanding of how to cope in complex and turbulent environments is necessary, but has not been widely researched.

Technology, mergers and acquisitions, changing workforce demographics, constantly shifting organizational strategies, new ways of working, global competition – all of these factors generate chronic organizational uncertainty. This article focuses on the nature of integrated portfolio strategies (IPS) which companies in North America and Europe have adopted to manage organizational uncertainty. It draws on the developing work on the science of complexity and adaptive strategies to explore issues of standardization and customization, supply chain relationships, knowledge and workplace options. It argues that uncertainty is best met with a diverse set of options that continually emerge and disappear over time in response to changing business conditions.

The purpose of this paper is to examine the impact of board busyness on firm efficiency in the context of directors’ experience, specifically on directors’ experience that moderates the impact of board busyness on firm efficiency. Directors’ experience is examined by exploring both depth (board tenure) and breadth (number of former listed directorship) of experience.

This paper employs data envelopment analysis (DEA) to examine firm efficiency. Then, fixed effect panel regression analysis is applied to test the direct and moderating effect based on a sample of firms in the selected Asia-Pacific countries.

Significant positive evidence for the moderating effect of directors’ experience on the impact of board busyness on firm efficiency is documented.

Findings are essential for managers, country policymakers and potential investors as inputs to improve the current company practices, laws and policies through the notion that directors’ experience does enable the busy board to contribute to improved firm efficiency.

This paper contributes to the debated perspectives on board busyness by providing initial evidence that directors’ experience positively moderates the impact of board busyness on firm efficiency.

The purpose of this paper is to enhance the understanding of the long-debated impact of board busyness within a new framework of firm efficiency in the selected developed and developing Asia–Pacific countries, by assessing the moderation of directors' education towards the relationship between board busyness and firm efficiency. The extant literature on board busyness demonstrates to a lack of clarification of the relationship between board busyness and firm efficiency.

The sample for this paper comprises a panel data of 800 firms in a cross-country context of the selected developed and developing Asia–Pacific countries during the recent period of 2009–2015. This paper performs a non-parametric Data Envelopment Analysis to measure firm efficiency and panel regression analysis to examine the moderation of directors' education.

This paper provides support for the busyness hypothesis by documenting that the busy boards are likely to reduce firm efficiency. Moreover, this paper renders support to the upper-echelons theory by demonstrating that the impact of board busyness on firm efficiency is likely to turn positive in the presence of directors' education.

This paper highlights practical implication for managers especially in the Asia–Pacific region who seek to enhance firm efficiency, which is essential for firms in attaining the primary goal of profit maximization.

This paper builds on the extant literature by providing a contemporary research path regarding the moderation of directors' education to explain the long-debated impact of board busyness within a new framework of firm efficiency, based on a recent and significant sample of Asia–Pacific countries.