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An orthogonal array technique is used in the present work to investigate, numerically, the effects of the swirler and the primary jets on the characteristics of the recirculation zone of a can‐type gas turbine combustor. The computer code used for this purpose is first validated with the available experimental data. The effects of change in the percentage flow rate through the swirler, the swirl number, the hub diameter of the swirler and the diameter of the primary injection holes (which influences the velocity of the jets) are estimated first. It is found that the flow rate through the swirler and the size of the primary injection hole have much more influence on the characteristics of the recirculation zone than the swirl number and the hub diameter of the swirler. But the earlier studies show that for a given flow rate through the swirler, the swirl number and swirler geometry have considerable influence on the characteristics of the recirculation zone in the absence of primary jets. Therefore it is inferred that there may be a critical point, based on the ratio of flow rate through the swirler to that of primary holes, beyond which the effects of swirl number and the swirler geometry dominate the effect of primary jets in determining the characteristics of the recirculation zone. This critical point is determined by gradually reducing the flow through the primary holes. It is found that, initially, the recirculation ratio (ratio of the mass of fluid recirculated to that sum of the mass flow rate through the swirler and through that of primary hole) reduces because of weakening of the primary jets but after the critical point it increases because of the swirler effect taking over the role of providing the recirculation. It is also observerd that the length of the recirculation zone increases as the strength of the primary jets reduces.

Existing models of decline and turnaround assume an automatic initiation of a turnaround strategy when decline occurs. However, extended decline over time suggests that the turnaround strategy did not match the causality and severity of the situation. Borrowing from the crisis management literature, this paper argues that a triggering event or events needs to shock incumbent management into realizing that different action is called for. Such triggering events, or triggers, also play a role in the turnaround process by influencing strategies and inducing management changes. Incorporating the need for, and role of, triggers in understanding the decline/turnaround sequence helps explain the iterative and non‐sequential nature of this process.

The purpose of this study is, to compare laser-based additive manufacturing and subtractive methods. Laser-based manufacturing is a widely used, noncontact, advanced manufacturing technique, which can be applied to a very wide range of materials, with particular emphasis on metals. In this paper, the governing principles of both laser-based subtractive of metals (LB-SM) and laser-based powder bed fusion (LB-PBF) of metallic materials are discussed and evaluated in terms of performance and capabilities. Using the principles of both laser-based methods, some new potential hybrid additive manufacturing options are discussed.

Production characteristics, such as surface quality, dimensional accuracy, material range, mechanical properties and applications, are reviewed and discussed. The process parameters for both LB-PBF and LB-SM were identified, and different factors that caused defects in both processes are explored. Advantages, disadvantages and limitations are explained and analyzed to shed light on the process selection for both additive and subtractive processes.

The performance of subtractive and additive processes is highly related to the material properties, such as diffusivity, reflectivity, thermal conductivity as well as laser parameters. LB-PBF has more influential factors affecting the quality of produced parts and is a more complex process. Both LB-SM and LB-PBF are flexible manufacturing methods that can be applied to a wide range of materials; however, they both suffer from low energy efficiency and production rate. These may be useful when producing highly innovative parts detailed, hollow products, such as medical implants.

This paper reviews the literature for both LB-PBF and LB-SM; nevertheless, the main contributions of this paper are twofold. To the best of the authors’ knowledge, this paper is one of the first to discuss the effect of the production process (both additive and subtractive) on the quality of the produced components. Also, some options for the hybrid capability of both LB-PBF and LB-SM are suggested to produce complex components with the desired macro- and microscale features.

Product failures can lead to customer dissatisfaction, negative brand attitudes and a loss of brand equity. The purpose of this paper is to investigate whether extended warranties offer a mechanism to mitigate the negative effects of product failure and the mediating role of positive and negative self-directed emotions.

The hypotheses are tested using two 2 × 2 between-subjects experiments with product failure and warranty purchase as the two factors, attitude toward the brand as the dependent variable, positive and negative self-directed emotions as mediating variables and attitude toward warranties as a covariate.

It is found that the decline in attitude toward the brand due to product failure is greater among customers purchasing an extended warranty, than among those who do not. Moreover, positive and negative self-directed emotions mediate this relationship.

Manufacturers are for the most part not involved in distribution or administration of extended warranties, which are mainly sold through retailers and administered by companies that specialize in extended warranties. The study findings indicate that contrary to industry practice, consumer-durable manufacturers should consider more active management and promotion of extended warranties to protect their brand’s equity from the negative effects of product failure.

The present data illustrate the effectiveness of utilizing theoretically guided models to develop consumer-based micro-segmentation strategies. The results provide marketers with a powerful discriminant function calculated from six variables to profile consumers and make informed decisions regarding promotional content and channel delivery to stimulate processing of marketing communication. The function also enables marketers to carve out casual, moderate, and loyal market segments with 74.3 per cent accuracy utilizing only 18 survey questions.

This paper examines the relationship between brand associations (anything in the consumer's mind linked to a specific team brand) and brand loyalty in US professional sport. To study the relationship between 13 brand association dimensions and brand loyalty, a survey of professional sport consumers was completed (N = 929). Results of multiple regression analysis revealed positive relationships between fan identification, escape, nostalgia, and product delivery, and brand loyalty. Negative relationships were found between tradition, star players, and peer group acceptance, and brand loyalty.

Researchers have investigated the link between business strategy and performance, the process of resource acquisition and employment, and issues associated with strategy implementation. However, empirical investigations into the moderating or mediating effects of resource deployment and implementation in the strategy‐performance relationship have been lacking. Data analyzed in the present study lends support for the notion that the appropriate strategy should be aligned with specific resource competencies if the strategy is to be successful.

Human resource development (HRD) has been considered in enhancing organisational operations as human resources are vital for organisational performance. This study aims to examine the role of HRD on the effectiveness of public procurement in Tanzania.

This study employed a cross-sectional research design under which data was collected from 168 procurement professionals in Dodoma city, Tanzania. Structural equation modelling (SEM) was employed to analyse the collected data and examine the structural relationships between HRD and the effectiveness of public procurement in Tanzania.

The findings revealed that all the variables of human resource development; career development, training and performance appraisal, are statistically significant and positively related to the effectiveness of public procurement. Therefore, the findings reveal that career development, training and performance appraisal as HRD practices play an important role in enhancing the effectiveness of public procurement in the surveyed public procuring organisations in Tanzania.

This current study divides HRD into three main practices: career development, training and performance appraisal. This limits the study's applicability to other HRD practices that organisations may institutionalize to public procurement professionals who work in various public organisations in Tanzania.

This paper integrates the concept of HRD and public procurement effectiveness. Therefore, the study adds value to the literature on human resource management and public procurement management.

The objective of this research is to provide insight into the management of service quality and emotions across customer relationships in the business‐to‐consumer market and to identify which segmentation method, i.e. conceptual versus data‐driven, is more effective for this purpose.

A cross‐sectional customer satisfaction survey conducted in the hotel industry was used to test the predictions. The respondents were Norwegian customers (n=689) of an international hotel chain, interviewed by telephone through a professional marketing research bureau. Several statistical analyses were applied to analyze the data, i.e. Cluster, MANOVA and regression. The conceptual model was estimated using PLS.

It would appear that the weaker the relationship segment, the more quality‐based and disappointing is the customer experience. The stronger or closer the relationship segment, the more balanced (with respect to price and quality) and joyful is the experience. One segmentation method seems to be more efficient than the other in this context.

The sample consists of Norwegian customers from the hotel industry represented by the business customer segment. There are more men than women in the samples.

The findings will allow service providers to develop more effective product‐service‐price offerings and manage the emotional responses of customers with whom they have very different relationships.

This is the first scientific study to examine just how the role of emotions varies across relationship segments while comparing the findings from two different segmentation techniques.

This conceptual article presents a theoretical approach to understanding the atmosphere at sports stadiums. Using the environmental psychology behavioural model proposed by Mehrabian & Russell (1974), and taking into account recent findings in consumer research, we develop a comprehensive framework for investigating this atmosphere. The framework highlights the role of emotions elicited by different stimuli in sports stadiums. We also suggest a number of direct and indirect influences on behavioural outcomes, caused by the emotional reactions and personal predispositions of spectators - influences that are of economic relevance. The proposed framework also forms a starting point for future empirical studies.