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The purpose of this study is to evaluate and compare the mechanical performance of FFF parts when subjected to post processing thermal treatment. Therefore, a study of the annealing treatment influence on the mechanical properties was performed. For this, two different types of Nylon (PA12) were used, FX256 and CF15, being the second a short fibre reinforcement version of the first one.

In this study, tensile and flexural properties of specimens produced via FFF were determined after being annealed at temperatures of 135°C, 150°C or 165°C during 3, 6, 12 or 18 h and compared with the non-treated conditions. Differential scanning calorimetry (DSC) was performed to determine the degree of crystallinity. To evaluate the annealing parameters’ influence on the mechanical properties, a full factorial design of experiments was developed, followed by an analysis of variance, as well as post hoc comparisons, to determine the most significative intervening factors and their effect on the results.

The results indicate that CF15 increased its tensile modulus, strength, flexural modulus and flexural strength around 11%, while FX256 presented similar values for tensile properties, doubling for flexural results. Flexural strain presented an improvement, indicating an increased interlayer behaviour. Concerning to the DSC analysis, an increase in the degree of crystallinity for all the annealed parts.

Overall, the annealing treatment process cause a significant improvement in the mechanical performance of the material, with the exception of 165°C annealed specimens, in which a decrease of the mechanical properties was observed, resultant of material degradation.

In industry, fused filament fabrication (FFF) offers flexibility and agility by promoting a reduction in costs and in the lead-time (i.e. time-to-market). Nevertheless, FFF parts exhibit some limitations such as lack of accuracy and/or lower mechanical performance. As a result, some alternatives have been developed to overcome some of these restrictions, namely, the formulation of high performance polymers, the creation of fibre-reinforced materials by FFF process and/or the design of new FFF-based technologies for printing composite materials. This work aims to analyze these technologies.

This work aims to study and understand the advances in the behaviour of 3D printed parts with enhanced performance by its reinforcement with several shapes and types of fibres from nanoparticles to continuous fibre roving. Thus, a comprehensive survey of significant research studies carried out regarding FFF of fibre-reinforced thermoplastics is provided, giving emphasis to the most relevant and innovative developments or adaptations undergone at hardware level and/or on the production process of the feedstock.

It is shown that the different types of reinforcement present different challenges for the printing process with different outcomes in the part performance.

This review is focused on joining the most important researches dedicated to the process of FFF-printed parts with different types reinforcing materials. By dividing the reinforcements in categories by shape/geometry and method of processing, it is possible to better quantify performance improvements.

More complexity, less freedom, distrust and a lack of information seem to pose threats to the success of partner relationships in accounting firms, as approximately 70% of business partnerships fail globally, undermining SDG 17. The low competitive intensity in this industry seems not to help the current situation. Yet, the existing strategic alliance (SA) literature have been somewhat sluggish in adequately addressing how partnership attributes (PAs) affect partnership success (PS) and how brand competition (BC) impacts this relationship. In response, this conceptual work addresses the impact of PAs on PS in accounting firms. It further explores the BC conditions under which the PAs–PS connection may be intensified.

Incorporating theories and empirics on six distinct topics, this study presents a conceptual model and ten hypotheses that are worth testing in future research.

This research finds that PAs will be favourably linked to PS, and this favourable association will be positively moderated by BC such that the PAs–PS connection will be more pronounced if BC within the accounting industry is high than low.

Further research is needed to empirically test the suppositions made. Also, they could extend the proposed framework to cover other moderators like technological turbulence, market dynamism and government regulation.

Practical lessons for governments, shareholders, chief executive officers, consultants and other industry players, particularly those who are interested in the success of accounting partnership firms, are deliberated.

This study demonstrates how PAs and BC interact to foster PS. It also provides a baseline information for upcoming researchers to investigate other external factors under which the PAs–PS connection may be improved.

Nonlinear model predictive control (NMPC) is emerging as a way to control unmanned aircraft with flight control constraints and nonlinear and unsteady aerodynamics. However, these predictive controllers do not perform robustly in the presence of physics-based model mismatches and uncertainties. Unmodeled dynamics and external disturbances are unpredictable and unsteady, which can dramatically degrade predictive controllers’ performance. To address this limitation, the purpose of this paper is to propose a new systematic approach using frequency-dependent weighting matrices.

In this framework, frequency-dependent weighting matrices jointly minimize closed-loop sensitivity functions. This work presents the first practical implementation where the frequency content information of uncertainty and disturbances is used to provide a significant degree of robustness for a time-domain nonlinear predictive controller. The merit of the proposed method is successfully verified through the design, coding, and numerical implementation of a robust nonlinear model predictive controller.

The proposed controller commanded and controlled a large unmanned aerial system (UAS) with unsteady and nonlinear dynamics in the presence of environmental disturbances, measurement bias or noise, and model uncertainties; the proposed controller robustly performed disturbance rejection and accurate trajectory tracking. Stability, performance, and robustness are attained in the NMPC framework for a complex system.

The theoretical results are supported by the numerical simulations that illustrate the success of the presented technique. It is expected to offer a feasible robust nonlinear control design technique for any type of systems, as long as computational power is available, allowing a much larger operational range while keeping a helpful level of robustness. Robust control design can be more easily expanded from the usual linear framework, allowing meaningful new experimentation with better control systems.

Such algorithms allows unstable and unsteady UASs to perform reliably in the presence of disturbances and modeling mismatches.

Collective Investment Schemes in Securities (‘CISS’) and Collective Investment Schemes in Property (CISP’) are common business vehicles in the South African economy. Nevertheless, there is still some uncertainty with regard to the tax treatment of these business structures, as the application of the specific income tax and capital gains tax provisions applicable to CISS and CISP results in several anomalies. The purpose of this article is to identify and highlight these anomalies by discussing the specific income tax and capital gains tax provisions applicable to CISS and CISP, and to suggest how some of these anomalies should be treated for tax purposes. It is submitted that the legislator did not consider the legal nature and practical operation of a CISS when the tax provisions for CISS were drafted. The tax treatment of CISP is also not without difficulties, especially where the CISP is constituted as an open‐ended investment company (OEIC’).

Purpose – To show the properties of performance measurement and management systems (PMMS) used dialogically and the association between the dialogic use of PMMS and the characteristics of the organizational relationships between parent companies and foreign subsidiaries.

Design/Methodology/Approach – Data were collected through a questionnaire e-mailed to large foreign subsidiaries of multinational firms operating in various industries. Hypotheses regarding factors associated with the extent to which PMMS are used dialogically between parent companies and foreign subsidiaries were tested based on responses to 136 usable questionnaires (45% response rate).

Findings – PMMS are used more dialogically within relationships between parent companies and subsidiaries characterized by subsidiary strategic role and organizational interdependence. Measurement diversity and perceived comprehensiveness of PMMS are higher if PMMS are used more dialogically. Finally, the dialogic use of PMMS is positively associated with subsidiary size and the emphasis on collaboration in the parent company’s national culture.

Originality/Value – In contrast to prior management accounting research that is focused on the outcomes of different styles of use of PMMS, this study shows organizational characteristics and PMMS properties associated with the dialogic use of PMMS. Moreover, this study advances the traditional view of the international business literature that conceives PMMS as bureaucratic systems employed by parent companies to coercively control foreign subsidiaries.

This study aims to examine the impact of terrorism on risk perception and travel behaviour of the Dutch market towards Sri Lanka.

The research process involved an online self-administered method created with one of the leading research and web-based survey tools called Qualtrics. The questionnaire was filled in by 328 respondents.

Findings indicate that Sri Lankan is perceived to be a relatively safe destination. However, the likeliness of visiting the country is unlikely. The respondents with past travel experience (PTE) perceive Sri Lanka to be safer than those without PTE and are more likely to revisit. Male respondents have a higher safety perception of Sri Lanka than women. Most of the respondents see Sri Lanka as an attractive destination and would consider travelling there with children.

The majority of the respondents are female and aged between 18 to 29 years old. The majority of the respondents’ children were already 19 or older and not accompanying their parents on holiday. This study has managerial implications for Sri Lanka’s tourism board that could work on developing a marketing strategy that focusses on promoting Sri Lanka as a safe destination in combination with all the other unique selling points.

To the best of author’s knowledge, no analysis has been so far published with a focus on the impact of terrorism on risk perception and attitudes of the Dutch tourist towards Sri Lanka. The aim of this paper is to close the existing gap in the literature and to provide valuable knowledge on the influence of terrorism on risk perception and attitudes of the Dutch tourists’ travel behaviour towards Sri Lanka as a destination.

The marginalization of women on boards is a heavily discussed topic across the world, especially in Ghana. Apart from estimating the link between boardroom gender diversity and technical efficiency of banks, this study aims to test the presence of upper echelons theory in the Ghanaian banking sector.

The study examines data from 2000 to 2019 annual reports of 23 banks in Ghana. The stochastic frontier analysis is used to estimate the impact of boardroom gender diversity on technical efficiency of banks in Ghana.

This study finds that greater boardroom gender diversity generates technical efficiencies for banks. The results remain unchanged after accounting for bank types (listed and non-listed). Thus, all banks benefit in terms of technical efficiency from more boardroom gender diversity. The upper echelons theory is validated in the Ghanaian banking context. Overall, the study supports pro-gender diversity on boards.

The results have implications at corporate, social and national levels. It supports the need for policies that improve greater boardroom gender diversity.

This study adds to a growing number of non-developed countries by investigating the link between the boardroom gender diversity and technical efficiency of banks in Ghana, a country which historically has had minimal female participation in the workforce. New insight is, therefore, offered into this relationship by using data which examines the technical efficiency of banks periods before and after the Women in Finance Charter in 2016.

This paper aims to examine the impact of diversity of board members’ educational qualifications on the financial performance of banks in Ghana.

The present study applies system generalized methods of moments as an econometric model in carrying out the analysis. The study yielded a usable sample of 28 banks spanning from 2001 to 2016.

The paper concludes that the Ghanaian banking sector profit diverges and invalidates the convergence theory or “catch-up effect”. Specifically, educational qualifications of board members are relevant to banks’ financial performance. Across all the models used, board members with a first degree have a significant positive impact on performance. The opposite is the case for board members with Doctor of Philosophy (PhD).

Unobservable characteristics such as entrepreneurial skills and intellectual competence experiences are excluded from the study because of the difficulties in measuring these variables. Notwithstanding, the exclusion of these characteristics does not invalidate the general outcome of the study.

The present study examines the impact of diversity of board members’ educational qualification on financial performance in the context of Sub-Saharan Africa, particularly Ghana. It also extends the existing literature by decomposing the banking sector into listed, non-listed, foreign and domestic banks.