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Modern unmanned air vehicles (UAVs) are usually equipped with rotors connected to electric motors that enable them to hover and fly in all directions. The purpose of the paper is to design optimal composite rotor blades for such small UAVs and investigate their aerodynamic performances both computationally and experimentally.

Artificial intelligence method (genetic algorithm) is used to optimize the blade airfoil described by six input parameters. Furthermore, different computational methods, e.g. vortex methods and computational fluid dynamics, blade element momentum theory and finite element method, are used to predict the aerodynamic performances of the optimized airfoil and complete rotor as well the structural behaviour of the blade, respectively. Finally, composite blade is manufactured and the rotor performance is also determined experimentally by thrust and torque measurements.

Complete process of blade design (including geometry definition and optimization, estimation of aerodynamic performances, structural analysis and blade manufacturing) is conducted and explained in detail. The correspondence between computed and measured thrust and torque curves of the optimal rotor is satisfactory (differences mostly remain below 15%), which validates and justifies the used design approach formulated specifically for low-cost, small-scale propeller blades. Furthermore, the proposed techniques can easily be applied to any kind of rotating lifting surfaces including helicopter or wind turbine blades.

Blade design methodology is simplified, shortened and made more flexible thus enabling the fast and economic production of propeller blades optimized for specific working conditions.

This paper aims to understand the effect of extrusion conditions on the degree of foaming of polylactic acid (PLA) during three-dimensional (3D) printing. It was also targeted to optimize the slicing parameters for 3D printing and to study how the properties of printed parts are influenced by the extrusion conditions.

This study used a commercially available PLA filament that undergoes chemical foaming. An extrusion 3D printer was used to produce individual extrudates and print samples that were characterized using an optical microscope, scanning electron microscope and custom in-house apparatuses.

The degree of foaming of the extrudates was found to strongly depend on the extrusion temperature and the material feed speed. Higher temperatures significantly increased the number of nucleation sites for the blowing agent as well as the growth rate of micropores. Also, as the material feed speed increased, the micropores were allowed to grow bigger which resulted in higher degrees of foaming. It was also found that, as the degree of foaming increased, the porous parts printed with optimized slicing parameters were lightweight and thermally less conductive.

This study fills the gap in literature where it examines the foaming behavior of individual extrudates as they are extruded. By doing so, this work distinguishes the effect of extrusion conditions from the effect of slicing parameters on the foaming behavior which enhances the understanding of extrusion of chemically foamed PLA.

The purpose of this study is to scrutinize the extent of forward-looking (FL) disclosures and explore the impact of corporate governance (CG) on FL disclosures in integrated reporting (IR) in the context of the banking industry in Bangladesh.

Twenty-two listed banks in the Dhaka Stock Exchange (DSE) are selected as a sample from 2018 to 2022. For content analysis purposes, the study has developed an unweighted self-constructed disclosure index with 58 items and extracted data manually from the integrated annual report. Furthermore, descriptive statistics is conducted to analyze the extent of FL disclosures, and a pooled ordinary least squares regression model is used to examine the impact of CG (directors’ ownership, institutional ownership, foreign ownership, board of directors, independent directors, female directors and audit quality) on the FL disclosures.

This study reveals that the banking industry’s average FL disclosure score is only approximately 43%, indicating a meager degree of disclosures in Bangladesh’s well-structured sector. This study also finds that directors’ ownership, foreign ownership, female directors and audit quality have a statistically significant and positive relationship with FL disclosures at a 5% significance level. By contrast, institutional directors and the board of directors have a substantial but negative impact on FL disclosures. However, the other exponential variable, independent directors, has no impact on FL disclosures.

This study has some limitations, such as: i) the sample size is restricted to 22 banks, whereas nearly 36 banks are listed in the DSE. The sample size should be increased for better results. ii) The study only considers the banking sector with a small sample, but other sectors have been omitted from the sample. iii) The data have been extracted from the annual report, but other relevant sources such as banks’ websites, prospectuses, press releases, and media releases are not considered. iv) Finally, the self-constructed unweighted disclosure index is affected by subjective judgment. For depth analysis, a weighted method for content analysis purposes will be applicable.

Since there is no specific guideline for FL disclosures, this study suggests that the practical implication is for the regulatory body and policymakers to take the initiative to design a framework for FL disclosures that will improve disclosure quality. Second, they can investigate the independent director’s role in the banking sector to discover the existence of old-boy network problems.

Investors will benefit from the proper judgment about the firm’s forward-looking disclosures, hence making effective decisions.

To the best of the authors’ knowledge, no particular study has been conducted on CG mechanisms and FL disclosures in the IR perspective of the banking sector in Bangladesh. So, this study may contribute to the existing literature.

The primary objective of this case was to grant the students an exposure to the students regarding how to manage a retail business during an economic crisis. In this case, all three of the aforementioned objectives as the students were given opportunity to dissect the business process through business model canvas, find out the key success factors and more importantly, were encouraged towards cost cutting behaviour by presenting the real-life dilemmas that were faced by an actual entrepreneur. Furthermore, the students were shown the importance of stakeholder management through this case, as support is very much needed for the retailers from macro-economic and micro-economic level.

This case study is the story of Global Gadget Limited, a premium retailer of cell phones and other relevant devises, which is located in Dhaka, the capital city of Bangladesh. The story is revolving around the challenge that Mr Shahadat Hossain Dipto, the owner of Global Gadget is facing over the past two years. Dipto mainly runs his business by selling budget phones from brands like Oppo, Xiaomi, Samsung and Vivo to the middle class and lower middle-class people of Bangladesh, who are very much cost conscious. To persuade these customers to buy his phones, he offers discounts, free gifts, equated monthly instalment services (a monthly instalment plan for the customers who cannot afford to pay the full amount when buying the phone) and sometimes even lottery. In the process, if he can sell more phones, these brands reward him with attractive commissions and all the necessary supports that help him run the business with marginal profit. However, due to the Russia–Ukraine war, he is now in crisis as the resulting economic crisis is causing a price increase on these phones, while drying out his customer’s pockets. This case study is designed to teach the students the importance of product segmentation, inventory management, cost management and relationship management to the students and future entrepreneur, so that they can understand, what does it take for an entrepreneur to survive an economic crisis.

This case study is aimed at undergraduate, masters’ students in business schools and Master of Business Administration students or short course executives and for the students of entrepreneurship education programme.

Teaching notes are available for educators only.

CSS3: Entrepreneurship.

In a pandemic framework (COVID-19), this chapter explores the impact of the global economy and socio-cultures concerning three axes: recreational, tourism, and hospitality. Although we slowly see an economic revival, it is well known that this sector of study is very susceptible to being affected by the context of nations. Following restrictions and measures taken by governments around the world to reduce the number of cases of coronavirus infections, many nations closed their borders, affecting international travel and by 2020 tourism had been reduced to the near cessation of operations due to the imminent fear of this poorly studied disease, and the service sector was negatively affected. It should be added that, according to the World Tourism Organization's projections, a decrease of between 20 and 30% is forecast for 2020 compared to the previous year.

The study aims to investigate the relationship between transformational, transactional leadership and employee retention with the mediating effect of employee engagement.

Using judgemental sampling, data were collected from 650 employees serving at different levels in the pharmaceutical industry of Bangladesh. Structural equation modeling was employed to test the hypothesized relationships using AMOS.

The study found that transformational and transactional leadership significantly impact employee retention. The direct effects of transformational leadership (TFL) on employee engagement were found to be significant, while transactional leadership (TSL) has no significant direct influence on employee engagement. The output of the mediation analysis revealed that employee engagement significantly mediates the relationship between TFL and employee retention, whereas it showed an insignificant relationship between TSL and employee retention.

Based on the findings and the literature support, it can be postulated that an appropriate leadership style, especially TFL, that drives employee engagement can influence employees to stay with the organization longer. The study recommends that managers and leaders comprehend the importance of leadership and its appropriateness to retain valued employees by ensuring high workplace engagement.

The study would provide a unique insight into TFL and TSL practices and their impact on the pharmaceutical industry’s employee retention. This study also extends the research on employee engagement as a mediator between TFL and TSL and employee retention.