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This study aims to investigate the impact of the macroeconomic environment on South African industrial sector returns.

Using standardized coefficients derived from time-series factor models, the authors quantify the impact of macroeconomic influences on industrial sector returns. The authors analyze the structure of the resultant residual correlation matrices to establish the level of factor omission and apply a factor analytic augmentation to arrive at a specification that is free of omitted common factors.

The authors find that global influences are the most important drivers of returns and that industrial sectors are highly integrated with the global economy. The authors show that specifications that comprise only macroeconomic factors and proxies for omitted factors in the form of residual market factors are likely to be underspecified. This study demonstrates that a factor analytic augmentation is an effective approach to ensuring an adequately specified model.

The findings have a number of implications that are of interest to investors, econometricians and researchers. While the study focusses on a single market, the South African stock market, as represented by the Johannesburg Stock Exchange (JSE), it is a highly developed and globally integrated market. In terms of market capitalization, it exceeds the Madrid Stock Exchange, the Taiwan Stock Exchange and the BM&F Bovespa. Yet, a limited number of studies investigate the macroeconomic drivers of the South African stock market.

Investors should be aware that while the South African domestic environment, especially political risk, has an impact on returns, global influences are the greatest determinants of returns. No industrial sectors are insulated from global influences and this limits the potential for diversification. This study suggests an alternative set of macroeconomic factors that may be used in further analysis and asset pricing studies. From an econometric perspective, this study demonstrates the usefulness of a factor analytic augmentation as a solution to factor omission in models that use macroeconomic factors to proxy for systematic influences that describe asset prices.

The contribution lies in providing insight into a large and well-developed yet understudied financial market, the South African stock market. This study considers a much broader set of macroeconomic factors than prior studies. A methodological contribution is made by estimating and interpreting standardized coefficients to discriminate between the impact of domestically and internationally driven factors. This study shows that should coefficients not be standardized, inferences relating to the relative importance of factors will differ. Finally, the authors unify an approach of using pre-specified factors with a factor analytic approach to address factor omission and to ensure a valid and readily interpretable specification.

Turbulent air flows within a channel with 45° angled rib turbulators on the top and bottom walls are numerically predicted using the numerical code. For the predictions, a v2-f turbulence model (velocity variance scale and elliptic relaxation factor model) is utilized. The paper aims to discuss these issues.

Three different rib arrangements with or without gap are investigated to present information on the effects of gap size on flow structure and heat transfer characteristics. Three-dimensional turbulent transport, and detailed flow structural characteristics are considered to provide new insight into the mechanisms which result in surface heat transfer augmentations.

Compared to the baseline rib arrangement, the numerically predicted results show that the parallel ribs with gap (where the width of the gap is two times of rib height) shows the highest local Nusselt number ratios. This is a result of locally increased vorticity distributions, as well as augmented local magnitudes of mixing, secondary flows, and turbulent transport. Local transport changes are less pronounced when the gap width of gap is 0.5 times of rib height. As a result, associated local and spatially averaged Nusselt number ratios are also lower for this arrangement.

Results will give improved heat transfer augmentation technologies.

The present investigation provides new information and insight into flow structural characteristics in a channel with rib turbulators, both with and without gaps, especially the mechanisms which result in surface heat transfer augmentations, which are not available in any other existing numerical or experimental investigation.

Analyses the adoption and use of an electronic messaging system (EMS) by members of a large R&D organisation. Develops and tests hypotheses about relationships among job categories, perceived social presence of an EMS, use of the system, and outcomes – such as effectiveness, communication flow and the use of extant media. Discusses lessons learned. Offers further areas of potential research.

This paper provides statistical evidence of the effects of overtime hours on worker productivity using aggregate panel data for 18 manufacturing industries within the US economy. An economic production function model is specified and estimated using data for the years 1956‐1991 provided by the US Department of Labor, Bureau of Labor Statistics, the US Department of Commerce, and the Federal Reserve Board. Standard approaches are applied to specify and estimate a factor‐augmented production function model, with possible effects of overtime on productivity incorporated through the specification of factor effort functions. The empirical results suggest that use of overtime hours lowers average productivity, measured as output per worker hour, for almost all of the industries included in the sample. These results hold up under several alternative specifications and estimation techniques, including controls or corrections for autocorrelation, heteroskedasticity, rates of capacity utilization, and possible endogeneity of the constructed variable representing use of overtime hours.

The purpose of this study is to focus on the feeling associated with being rejected by the preferred service brand, and its effect on consumer assessment of the alternate brand.

The data were collected using a self‐administered questionnaire in the context of higher education services targeted at the international market.

Consumers who do manage to get their preferred service brand tend to be more satisfied with the features of the obtained brand and exhibit higher levels of brand loyalty towards that brand. In comparison, consumers who end up with a service brand that is not their first choice seem to have lower levels of satisfaction with and loyalty towards the obtained brand.

A key limitation of this study is the sampling frame. Future studies should replicate this study in different service and product contexts and with different target population. In addition, the disconfirmation of expectations or desires within the framework of preferred brand attainment should be explored.

Managers should ensure that one's service brand is high in the consideration set. This has implications for service branding and brand positioning as well as fulfilling service brand promise through services elements. It also has implications pertaining to winning over new customers and retaining through superior service delivery – particularly the service augmentation elements, and the selection and training of service delivery personnel.

This study provides answers to a crucial question – “Can the number two brand ever achieve a prominent position or is it doomed to remain in the second place waiting to be picked only when consumers do not get their first choice?”

The aim of this paper is to investigate the convective heat transfer in swirl tubes, which are obtained by roto‐translating a circular section eccentric with respect to the rotation axis. The geometry is numerically investigated with the aim of evaluating the convective heat transfer enhancement effect due to the secondary flow induced by the centrifugal force.

The governing equations, i.e. continuity, momentum and energy equations, are integrated numerically within Comsol Multiphysics^® environment, under the assumption of incompressible Newtonian and constant properties fluid and of periodically fully developed laminar flow for what concerns both the hydrodynamic and the thermal problem under the uniform wall heat flux thermal boundary condition.

The heat transfer performance of the geometry is discussed in relation to the flow pattern. In particular, the numerical results show that two different stable flow regimes may exist, according to the ratio of the Reynolds number to the dimensionless helix pitch. The Nusselt number augmentation becomes significant for high Prandtl number fluids when a critical Re/P* value, corresponding to the onset of the centrifugal forces induced secondary flow, is reached.

The geometry here investigated represents an interesting solution to enhance the convective heat transfer in situations in which the flow, although disturbed, persists in the laminar regime. This type of enhanced tubes shows then interesting heat transfer performances (which becomes particularly significant for high Prandtl number values) by thus suggesting convenient applications also for highly viscous fluids which are often treated under the laminar flow regime.

The famous Uzawa (1961) balanced growth theorem has exercised a tyranny of sorts over macroeconomics for decades. It is the prime reason why researchers use Cobb–Douglas production functions and abstract from considering movements in factor shares. Others have had to recourse to complex explanations for long-run labor augmentation in technical progress. In this chapter, we discuss the issues arising from this problem and propose a way of achieving balanced growth with a short-run production function where the elasticity of factor substitution is less than one, and capital augmenting technology shocks can be permanent. We do so by allowing firms to choose the relative reliance on capital in the production technology and introducing a suitable modification of the production function. We also provide some model simulations in the context of a simple deterministic neoclassical growth model.

The main aim of this research is to portray how augmented reality (AR) characteristics (augmentation, interactivity, personalization, spatial presence, novelty, entertainment and informativeness) can enhance online customer experience (OCE).

This study conceptualizes a new framework that proposes various relationships between AR characteristics and OCE.

This study is extending the relationships between AR and OCE by including various AR characteristics that have not been tackled by the previous research.

This research provides an original framework on the relationship between AR characteristics and OCE through highlighting the role of media richness theory. The study is considered the first of its kind to combine these AR characteristics and customer experience in a comprehensive framework.

The purpose of the study is to propose a novel implementation of twisted tape in sinusoidal wavy-walled tubes to enhance the rate of heat transfer without compromising thermal efficiency. The study numerically investigates the fluid flow characteristics and analyzes the effect of different geometrical configurations, including wall wave amplitude, tape twist angles and nanoparticle volume fractions, on heat transfer improvement and performance factor.

This problem is numerically investigated using computational fluid dynamics, and the method is the finite volume method. A two-phase mixture model is used for nanofluid modeling.

The study investigated the effect of wall waviness, twisted tape, and nanoparticles on forced convective heat transfer and friction factor behavior in laminar pipe flow in three different Reynolds number regimes. The results showed that implementing twisted tape in wavy tubes significantly increased the rate of heat transfer and the performance factor, with the best twist ratio between 90 and 180°. Adding nanoparticles also enhanced heat transfer and performance factor, but to a lesser extent than wavy wall-twisted tape combinations. The study suggests selecting a proper combination of wavy wall and twisted tape at each Reynolds number to achieve an optimum solution.

To the best of the authors’ knowledge, the implementation of the selected passive methods in sinusoidal wavy tubes has not been studied before, and no previous studies have taken into account such a mix of heat transfer improvement techniques.

The study examined the personal information management (PIM) challenges encountered by faculty in six universities in Ghana, their information refinding experiences and the perceived role of memory. The study tested the hypothesis that faculty PIM performance will significantly differ when the differences in the influence of personal factors (age, gender and rank) on their memory are considered.

The study was guided by a sample survey design. A questionnaire designed based on themes extracted from earlier interviews was used to collect quantitative data from 235 faculty members from six universities in Ghana. Data analysis was undertaken with a discrete multivariate Generalized Linear Model to investigate how memory intermediates in the relationship between age, gender and rank, and, refinding of stored information.

The paper identified two subfunctions of refinding (Refinding 1 and Refinding 2) associated with self-confidence in information re-finding, and, memory (Memory 1 and Memory 2), associated with the use of complimentary frames to locate previously found and stored information. There were no significant multivariate effects for gender as a stand-alone variable. Males who were aged less than 39 could refind stored information irrespective of the memory class. Older faculty aged 40–49 who possess Memory 1 and senior lecturers who possess Memory 2 performed well in refinding information. There was a statistically significant effect of age and memory; and rank and memory.

This study was limited to faculty in Ghana, whereas the study itself has implications for demographic differences in PIM.

Identifying how memory mediates the role of personal factors in faculty refinding of stored information will be necessary for the efforts to understand and design systems and technologies for enhancing faculty capacity to find/refind stored information.

Understanding how human memory can be augmented by technology is a great PIM strategy, but understanding how human memory and personal factors interplay to affect PIM is more important.

PIM of faculty has been extensively examined in the literature, and limitations of memory has always been identified as a constraint. Human memory has been augmented with technology, although the outcome has been very minimal. This study shows that in addition to technology augmentation, personal factors interplay with human memory to affect PIM. Discrete multivariate Generalized Linear Model applied in this study is an innovative way of addressing the challenges of assimilating statistical methodologies in psychosocial disciplines.