Thomas Vyncke, Steven Thielemans, Michiel Jacxsens and Jan Melkebeek
Flying‐capacitor multilevel converters (FCC) need a passive or active regulation of the capacitor voltages. Recently the trend is towards active control, often implemented…
Abstract
Purpose
Flying‐capacitor multilevel converters (FCC) need a passive or active regulation of the capacitor voltages. Recently the trend is towards active control, often implemented separately from the current control. The advantages of a true multi‐variable control sparked the interest to apply Model Based Predictive Control (MBPC) for FCC. In this paper an objective analysis method to evaluate the effects of several design choices is presented. The effects of the weight factor selection, model simplification, and prediction horizon expansion for MBPC of a 3‐level FCC are analyzed in a systematical way.
Design/methodology/approach
The analysis is mainly based on the mean square error (MSE) of current and capacitor voltage. The results are analysed for different lengths of the prediction horizon and for a wide range of weight factor values. Similarly the effect of a model simplification, neglecting the neutral point voltage, is studied when implementing MBPC for FCCs while considering the computational aspects. Validation of the simulation results is done by experiments on an FPGA‐based setup.
Findings
Including the effect of the neutral point voltage considerably increases the current control quality and a much wider range of good values for the weight factor exists. As this good range is not critically dependent on the current amplitude it is possible to select one weight factor value for all operating points. Furthermore, it is concluded that increasing the prediction horizon increases the computational load without improving the control quality.
Research limitations/implications
The effects of increasing the prediction horizon when including other controlled variables is to be investigated, as well as the robustness to modeling errors. The MSE analysis methodology is very suitable for this further research.
Practical implications
For practitioners of MBPC in power electronics the paper proves that by means of simulations and the MSE one value for weight factor can be chosen for all operating points. The paper clearly shows that a practical implementation is feasible and demonstrates that neglecting the neutral point voltage is not good practice.
Originality/value
The MSE‐based analysis is shown to be a systematical and unbiased methodology to evaluate the effects of design choices. The results from this analysis can be directly applied in practical setups.
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Since Richard Florida’s book The Rise of the Creative Class published in 2000, our attention has been drawn towards a peculiar characteristic of the cities where such a creative…
Abstract
Since Richard Florida’s book The Rise of the Creative Class published in 2000, our attention has been drawn towards a peculiar characteristic of the cities where such a creative class thrives, and that is tolerance. We intend to explore in this paper whether one can use Hofstede’s “Uncertainty Avoidance” dimension to ponder if societies that are “Uncertainty avoidant” can provide a nurturing soil for a creative class to emerge within their bosom. To discuss this question, we examine the case of the Province of Québec (Canada) and most specifically, that of the city of Montréal, a city that has been dubbed by many observers as a creative city. In other words, our question is can a creative class thrive in a city that is located in an “Uncertainty avoidant” cultural and political unit?
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Kristian J. Sund and Philipp Boksberger
The purpose of this paper is to test a number of hypotheses concerning the differences between senior and non‐senior travelers in the particular context of holiday rentals. A…
Abstract
Purpose
The purpose of this paper is to test a number of hypotheses concerning the differences between senior and non‐senior travelers in the particular context of holiday rentals. A further aim is to provide exploratory evidence for these differences.
Design/methodology/approach
A brief review of the extant literature leads into the formulation of some hypotheses. The hypotheses are tested using survey data. Data from the same survey are used to explore further data.
Findings
It was possible not only to find some evidence to support the hypotheses, but also to find significant differences between the preferences of seniors and non‐seniors, as well as between pre‐seniors and seniors. Thus, pre‐seniors exhibit a higher willingness to pay for holiday rentals than seniors, whereas seniors have a higher preference for domestic travel. Seniors are less interested in technology than other age groups. Originality/value –This paper reports on survey findings for a segment of the tourism market that has received practically no attention in the literature – the holiday rental market. The results pave the way for further investigations within this segment.
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Anna Torres, Leonor Vacas de Carvalho, Joana Cesar Machado, Michel van de Velden and Patrício Costa
Focusing on small- and medium-sized enterprises (SMEs), which are characterized by resource restrictions, this paper aims to explore consumer segment profiles by considering…
Abstract
Purpose
Focusing on small- and medium-sized enterprises (SMEs), which are characterized by resource restrictions, this paper aims to explore consumer segment profiles by considering demographic, personality and creativity traits to determine whether consumers with different profiles exhibit distinct affective reactions to different logo design types (organic, cultural and abstract).
Design/methodology/approach
This exploratory study incorporates recent methodological developments, such as the novel response style correction method, to account for response style effects in evaluations of affect toward logo design. In separate analyses, respondents are segmented according to response style–corrected logo affect and personality and creativity items. The segmentation analysis relies on reduced k-means, a joint dimension and cluster analysis method, which accounts for dependencies between items while maximizing between-cluster variability. A total of 866 respondents from the Iberian Peninsula (Portugal: n = 543; Spain: n = 323) participated.
Findings
Based on a study using unknown logos (proxy for lower levels of budget communication, characteristics of SMEs), results reveal that there are three segments of consumers based on their affective response toward logo design: logo design insensitives, cultural logo dislikers and organic logo lovers. These segments are associated with different personality traits, creativity and biological sex (although biological sex is not a discriminant variable).
Research limitations/implications
The decision not to control logos by color, to increase external validity, could limit the study’s internal validity if this aspect interacts with relevant study variables. Nevertheless, the empirical evidence can be used to further test associations between consumer profiles and responses to logo design.
Practical implications
Findings highlight the relevance of considering complex profile segments, combining demographics, psychographics and creativity to predict affective consumer responses to brand logo design. This research provides guidelines for SMEs when choosing or modifying their logo design to appeal to different consumer segments.
Originality/value
This study provides managers of SMEs (less present nowadays in empirical studies) with evidence suggesting that complex customer profiles help to understand differences in affective responses to natural logo designs. Furthermore, it relies on the use of a novel methodological development that improves the accuracy of the exploratory study developed.
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Zhiyuan Wang, Jagdeep Singh-Ladhar and Howard Davey
This paper aims to examine the indirect tax reform process in China. Specifically, it examines the reform of business tax to value-added tax. Inefficiencies within the new tax…
Abstract
Purpose
This paper aims to examine the indirect tax reform process in China. Specifically, it examines the reform of business tax to value-added tax. Inefficiencies within the new tax system are identified and discussed. The “business tax to value-added tax” reform was seen as an essential element in promoting the economic transition and stimulating the service industries (Jin and Jin, 2013).
Design/methodology/approach
The paper uses archival and current literature. In undertaking the study, the different periods of indirect tax are examined, prior to 1994, 1994-2012, the changes from 2012 culminating in the new 2017 regime. Attributes of “good” value-added tax (VAT) systems are covered as well as a comparison with New Zealand’s goods and services tax (GST).
Findings
The paper finds that to align with the international trend of indirect tax development and more efficiently accomplish the economic transition China needs to build a more neutral VAT system with fewer reduced rates and exemptions and the tax system have created tax inefficiencies and increased the compliance cost. VAT is imposing an increasingly significant impact on China’s national economy and industrial structure as well as accountants.
Originality/value
This is the first study that analyses the indirect tax reforms that are currently being implemented in China and as such has lessons for China but also for VAT/GST in general. We should not forget how special New Zealand’s GST is and the clarity of focus of those who implemented it!
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Johan Bruwer, Brigitte Roediger and Frikkie Herbst
The purpose of this paper is to illustrate the use of a domain-specific research instrument (the wine-related lifestyle (WRL)) to determine the different lifestyle-related wine…
Abstract
Purpose
The purpose of this paper is to illustrate the use of a domain-specific research instrument (the wine-related lifestyle (WRL)) to determine the different lifestyle-related wine market segments in a country and compare the findings cross-culturally.
Design/methodology/approach
The research instrument included 48 psychographic activities, interests and opinions (AIO) statements, plus socio-demographic, product consumption and purchasing questions. A final sample of 376 South African wine consumers was utilised, whereon exploratory and confirmatory factor analysis, combined with Hough’s Euclidean test, were applied to determine the existence of clusters (segments), assign descriptions to them, and link these to product consumption data.
Findings
Five wine segments recurred when comparing wine market segmentation studies cross-culturally. This means that cross-culturally, similar types of people drink wine with similar AIOs towards wine. In the South African market, four of these segments were identified.
Research limitations/implications
This study achieved a robust lifestyle-based market segmentation algorithm which can be used by researchers in different country environments for wine as a domain-specific product.
Originality/value
The contribution of this research is threefold in that it tested the WRL instrument in a cross-cultural context which is the first time this has been done; in the process it interpreted the wine consumer segments in South Africa for the first time; using a WRL-based (AIO) approach. The study demonstrated that market segmentation based on psychographic (lifestyle) behaviour is strengthened when supported by two additional segmentation methods, namely, socio-demographics and product involvement (purchasing and consumption).
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Won-Moo Hur, Hyun Kyung Kim and JungKun Park
The primary purpose of this research is to draw out in-depth lifestyle characteristics which can be used in new product development and marketing. To achieve this goal, this…
Abstract
Purpose
The primary purpose of this research is to draw out in-depth lifestyle characteristics which can be used in new product development and marketing. To achieve this goal, this research aims to explore US female household consumers ' lifestyle structures regarding food-related AIO and identify the values that discriminate best among different consumer segments.
Design/methodology/approach
A total of 518 US female consumers aged between 20 and 65 participated based on multi-stage stratified random selection of age. The cluster analysis was performed to identify meaningful segments.
Findings
Six segments of Wellbeing-oriented, Social- and dining-oriented, Family-oriented, Innovation- and action-oriented, Price-conscious, and Convenience-oriented were found. These segments show differences in motivation for buying kitchen appliances, evaluation of quality aspect of foods, consumption situations, and in socio-demographic characteristics.
Research limitations/implications
These results identify that a product-specific lifestyle helps one to understand the market better than product function even in a technology-oriented industry. Consumer electronics companies should concentrate on their potential target market and understand their specific needs.
Originality/value
The study found that refined and modified AIO-based research is effective in terms of consumer lifestyle analysis. In addition, employing the combination of multivariate analytical techniques made it possible to attain the major objectives of the study
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This study aims to propose a mathematical model for stacked multicell converters (SMCs), to be exploited in the analytic determination of natural voltage balancing dynamics of the…
Abstract
Purpose
This study aims to propose a mathematical model for stacked multicell converters (SMCs), to be exploited in the analytic determination of natural voltage balancing dynamics of the flying-capacitor (FC) stacked multicell multilevel converters, i.e. investigations of the start-up behavior, dynamic response, and natural voltage balancing phenomenon.
Design/methodology/approach
The crux of the proposed strategy is based on the closed-form analytic solution derivation for the switching functions used in the switching of the SMCs operated under phase disposition (PD) and phase shifted carrier (PSC) pulse width modulation (PD-PSC-PWM) technique. Hence, the suggested approach develops an analytic solution for the Fourier series and associated Fourier coefficients pertinent to the switching functions of the SMCs by obtaining the switching instants of the PD-PSC-PWM modulator in terms of Kapteyn series when the frequency of the triangular carrier waveform (fc) and that of the sinusoidal reference waveform (fr) have an integer ratio, i.e. f c · f r−1=k, k∈N.
Findings
This approach results into a model, first order differential equation based model, which can be readily developed for the SMCs with any number of levels expediting the investigation of their performance. Furthermore, by an experimental scrutiny conducted on a 4×2-cell-nine-level topology of an SMC, it is inferred that under PD-PSC-PWM modulation technique, FC voltages balance naturally for higher number of stacks and cells, therefore the natural balancing exist for high-level SMCs.
Research limitations/implications
Despite the sophistication of the proposed methodology and mathematical model, this study presents an alternative approach with high potential of applicability for derivation of the multilevel converter mathematical model exploiting the Kapteyn (Bessel-Fourier) series.
Practical implications
Numeric computation results of the proposed analytic model for the SMCs and the simulation results as well as investigational measurements taken from 2×2-cell-five-level and 4×2-cell-nine-level experimental set-ups are presented in order to substantiate the suggested approach, derived model, and verification of natural balancing.
Originality/value
This article and its innovations are original.
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Leeford Edem Kojo Ameyibor and Yvonne Kabeya Saini
This study aims to cluster psychographic activities, interests and opinions of alcohol quitters in behaviour change maintenance mode to form segmentation bases for social policy…
Abstract
Purpose
This study aims to cluster psychographic activities, interests and opinions of alcohol quitters in behaviour change maintenance mode to form segmentation bases for social policy and alcohol policy formulation that sustain the behaviour change.
Design/methodology/approach
A two-step cluster analysis was used to segment a cross-sectional sample of n = 501 former alcohol consumers based on their activity interest and opinion (AIO) framework through a multiple-response survey design.
Findings
Five clusters were found across five AIO themes of “people socialised with”, “relationship interest”, “ingredients of a good relationship”, “party activities” and “outing dressing”. The clusters were honesty-based relationship seekers, spiritual- and intellectual-based relationship seekers, attention seekers in a healthy relationship, self-conscious seeking a healthy relationship, and sincere, spiritual and intellectual-based relationship seekers.
Practical implications
The findings present an opportunity for social policy design that encourages alcohol-free social space creation, strong family ties, community and spiritual growth and incentives for long-term relationships as means of sustaining alcohol quitters’ behaviour. Equally, alcohol policies that match the themes of the clusters can be designed to aid sobriety sustenance.
Originality/value
This study advances knowledge of behaviour change maintenance and provides lifestyle segments of alcohol quitters as bases for further social and alcohol policy design to sustain gains in behaviour change.
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Lan Ye and Eyun-Jung Ki
The purpose of this paper is to explore British Petroleum’s (BP) crisis response on Facebook and factors contributing to its stakeholders’ perceptions of its crisis response…
Abstract
Purpose
The purpose of this paper is to explore British Petroleum’s (BP) crisis response on Facebook and factors contributing to its stakeholders’ perceptions of its crisis response strategies during the Deepwater Horizon oil spill.
Design/methodology/approach
Applying crisis response strategies, this study content analyzed BP’s crisis communication messages and Facebook users’ comments on BP America’s Facebook page.
Findings
The results revealed that information giving strategies dominated BP’s crisis response, and Facebook users were more likely to comment favorably when BP used information giving strategies and accommodative strategies. Bolstering strategies and third-party endorsement did not achieve anticipated effectiveness.
Originality/value
The findings of this study will contribute to effective application of crisis response strategies.