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The purpose of this paper is to increase our understanding of why firms, specifically small to medium‐sized enterprises (SMEs), participate in a programme for competence development and why firms use different strategies for competence development.

A study of 17 SMEs that all received support from the European Social Fund, Objective 3 programme. The collection of data is based on semi‐structured interviews with management/owners, internal project leaders, employees and union representatives, feedback seminars with representatives from the studied enterprises, and on analysis of documents.

The findings demonstrate that all SMEs reported driving forces for competence development relating to both external organizational conditions and internal organizational conditions, to at least a certain degree. Furthermore, there appears to be a strong relationship between observed patterns of driving forces and the strategy for competence development used by the firm.

The SMEs that experience a relatively stronger driving force for competence development initiate problem‐solving efforts to design and implement more elaborated strategies for competence development. The SMEs that experience a lesser degree of driving force for competence development implement less elaborated strategies for competence development.

The paper finds that both external and internal organizational conditions are important in understanding why SMEs undergo competence development programme. Furthermore, the importance of external and internal organizational conditions is not only limited to why the companies participate in a programme for competence development, but also for how they participate, i.e. the strategies used for competence development.

The motivation to perform research on feedback control system for unmanned aerial vehicles, a fact that each quadrocopter is unstable.

For this reason, it is necessary to design a control system which is capable of making unmanned aerial vehicle vertical take-off and landing (UAV VTOL) stable and controllable. For this purpose, it was decided to use a feedback control system with cascaded PID controller. The main reason for using it was that PID controllers are simple to implement and do not use much hardware resources. Moreover, cascaded control systems allow to control object response using more parameters than in a standard PID control. STM32 microcontrollers were used to make a real control system. The rapid prototyping using Embedded Coder Toolbox, FreeRTOS and STM32 CubeMX was conducted to design the algorithm of the feedback control system with cascaded PID controller for unmanned aerial vehicle vertical take-off and landings (UAV VTOLs).

During research, an algorithm of UAV VTOL control using the feedback control system with cascaded PID controller was designed. Tests were performed for the designed algorithm in the model simulation in Matlab/Simulink and in the real conditions.

It has been proved that an additional control loop must have a full PID controller. Moreover, a new library is presented for STM32 microcontrollers made using the Embedded Coder Toolbox just for the research. This library enabled to use rapid prototyping while developing the control algorithms.

In today’s technology, the significance of unmanned aerial vehicles is steadily increasing. Many unmanned aerial vehicles design, especially those used for military purposes, have achieved autonomy from human operators. Undoubtedly, one of the most crucial features of these aircraft is their vertical take-off and landing (VTOL) capability. Inspired by quadrotor methodology, this paper aims to conduct, a modeling of an aircraft with VTOL capabilities.

The impact of releasing air-launched missiles, considered as the useful payload carried during the flight of the aircraft, has been taken into account in this modeling. The release of air-launched missiles disrupts both the symmetric structure of the system and alters the mass and inertia parameters. Simulations were conducted to investigate scenarios involving the simultaneous release of all air-launched missiles and their release at different times.

The investigation focused on determining how quickly an aircraft, aiming to consecutively hit targets, can return to its desired trajectory. The time interval between the consecutive releases of two air-launched missiles has been identified.

It is crucial for a VTOL-capable aircraft to possess a unique modeling structure to examine its capability of releasing air-launched missiles in various scenarios. This entails understanding not only the aircraft’s VTOL functionality but also its ability to effectively release missiles in different operational conditions.

This paper aims to present a mathematical model of the dynamics of the unmanned aerial vehicle (UAV) vertical take-off and landing (VTOL). It will be used to develop control laws to a multirotor that is inherently unstable. Also, the model will be used to design algorithms to estimate the attitude of an object.

The physical model of UAV assumes that it is a rigid body with six degrees of freedom acted by forces generated by the propellers, motors, aerodynamic forces, gravity and disturbance forces. The mathematical model was described by differential equations. However, drive system (propeller, BLDC motor and BLDC motor controller) was described by six transfer functions. These transfer functions were demarcated with Matlab/Simulink identification toolbox from data received from a specially designed laboratory stand. Moments of inertia of the platform have been analytically determined and compared with empirical results from the pendulum. The mathematical model was implemented in Matlab/Simulink.

The paper confirms the need of designing mathematical models. Moreover, mathematical models show that some parts of the object are better to be replaced by experimental results than by equations, which is proved by the data. The paper also shows advantages of using Matlab/Simulink. What is more the simulation of the model proves that multirotor is an unstable object.

The test results show that drive units are strongly dependent on ambient conditions. An additional problem is the different response of the drive set to increasing and decreasing the control signal amplitude. Next tests will be done at different temperatures and air densities of the environment, also it is need to explore drag forces.

The mathematical model is a simplification of the physical model expressed by means of equations. The results of simulation like accelerations and angular rate are noise-free. However, available sensors always have their errors and noise. To design control loops and attitude estimation algorithms, there is a need for identification of sensors’ errors and noise. These parameters have to be measured.

The paper describes a solution of correct identification of drive unit, which is a main component of the UAV.

Most of the 3D printing machines do not comply with the requirements of on-site, large-scale multi-story building construction. This paper aims to propose the conceptualization of a tower crane (TC)-based 3D printing controlled by artificial intelligence (AI) as the first step towards a large 3D printing development for multi-story buildings. It also aims to overcome the most important limitation of additive manufacturing in the construction industry (the build volume) by exploiting the most important machine used in the field: TCs. It assesses the technology feasibility by investigating the accuracy reached in the printing process.

The research is composed of three main steps: firstly, the TC-based 3D printing concept is defined by proposing an aero-pendulum extruder stabilized by propellers to control the trajectory during the extrusion process; secondly, an AI-based system is defined to control both the crane and the extruder toolpath by exploiting deep reinforcement learning (DRL) control approach; thirdly the proposed framework is validated by simulating the dynamical system and analysing its performance.

The TC-based 3D printer can be effectively used for additive manufacturing in the construction industry. Both the TC and its extruder can be properly controlled by an AI-based control system. The paper shows the effectiveness of the aero-pendulum extruder controlled by AI demonstrated by simulations and validation. The AI-based control system allows for reaching an acceptable tolerance with respect to the ideal trajectory compared with the system tolerance without stabilization.

In related literature, scientific investigations concerning the use of crane systems for 3D printing and AI-based systems for control are completely missing. To the best of the authors’ knowledge, the proposed research demonstrates for the first time the effectiveness of this technology conceptualized and controlled with an intelligent DRL agent.

The results provide the first step towards the development of a new additive manufacturing system for multi-storey constructions exploiting the TC-based 3D printing. The demonstration of the conceptualization feasibility and the control system opens up new possibilities to activate experimental research for companies and research centres.

The entrepreneur is often conceptualised as an individualistic hero (Essers & Benschop, 2007; Gill, 2017). Although this portrayal has been criticised as highly romanticised (Acs & Audretsch, 2003) it is still influential in the contemporary entrepreneurship literature (Down, 2010). Consequently, prevailing social discourses around entrepreneurship may restrict and even prevent an individual to develop their own entrepreneurial identity (Down & Giazitzoglu, 2014; Gill, 2017). In order to explore this issue, this chapter presents insights into the entrepreneurial experience of student entrepreneurs by exploring the role of entrepreneurial and non-entrepreneurial identities in new venture creation. In-depth interviews were carried out with 11 student entrepreneurs who had, individually or in partnership with others, started a venture whilst they were enrolled in higher education courses.

These findings challenge the taken-for-granted assumptions entrenched in the characterisation of the homogenous entrepreneur (Jones, 2014) and suggest that individuals can arrive at entrepreneurship in different ways. In order to demonstrate the diversity of entrepreneurial identities, the chapter highlights those that fit the orthodox depiction of entrepreneurs through vignettes from Nicole and Georgie. This is then contrasted with alternative depictions through vignettes from Joanna, Christa, Darcie and Paige. The experience of the latter demonstrates how entrepreneurial identities are formed through role enactment and socialisation into entrepreneurial communities. The findings propose universities can support student entrepreneurship through both formal and informal activities. The broader conceptions of entrepreneurial identities with respect to the role of universities and enterprise education are considered.

The purpose of the paper is to extend prior research on the psychological effects of the Deepwater Horizon oil spill disaster by developing and testing a conceptual model in which exposure to the oil spill through clean-up activity, physical symptoms, worry about the impact of the oil spill on health, and the disruption of the gulf/ocean-related lifestyle were hypothesized as predictors of depressive symptoms.

The analysis included a randomly selected sample of 354 subjects from the three most Southern Mississippi counties. The Center for Epidemiologic Studies Depression Scale was used to measure depressive symptoms.

Results indicated that physical symptoms since the oil spill were related to depressive symptoms directly and indirectly through worry about the impact of the oil spill on health and the disruption of the gulf/ocean-related lifestyle. Worry about the impact of the oil spill on health was related to depressive symptoms directly and indirectly through the disruption of the gulf/ocean-related lifestyle.

Study results highlight that uncertainty and worry about the impact of the disaster played a critical role in understanding the psychological effects of the oil spill disaster, especially among coastal residents whose lifestyles were bound up with the gulf/ocean.

Though employees are important stakeholders of a brand, their role in building brand equity has long been neglected. This study aims to deepen the understanding of employees’ brand co-creation efforts and their contribution to employee-based brand equity (EBBE).

The study analyses implicit and explicit communication activities by employees on the social media network LinkedIn and quantifies the contribution of their posts to EBBE. Data has been gathered from more than 1,300 posts and 130 private accounts, representing different employee groups of five corporate brands.

The investigation illustrates the high importance of brand co-creation in social networks by employees and helps practitioners to better understand the underlying processes.

Case-study research has limitations of generalisability. However, the authors unveil important limits to exploiting the autonomy of employees’ word-of-mouth communication.

Under a co-creative perspective, every social media activity of an employee can be a positive contribution to a brand’s equity. Therefore, companies should closely monitor EBBE.

The authors draw on basic conceptual insights and empirical work by other researchers but extend and interpret them in a new context. The study provides initial indications of key antecedents of and barriers to successful management of employees’ brand co-creation activities.

The purpose of this paper is to explore the long‐term effects of qualitative interviews on respondents. The paper offers a reflexive account of the author's research practices with regard to “safeguarding” research participants and researcher accountability.

In 1999‐2002, 20 women and 18 men who are in dual earner marriages/partnerships were interviewed separately. The study was entitled “Hard Labour 1”. In this paper, It is explained how, in 2007, 17 “Hard Labour 1” participants were contacted for a follow‐up study entitled “Hard Labour Revisited”. They were asked, via telephone and e‐mail, whether (and if so, how) they perceived themselves to have been affected by their interview for “Hard Labour 1”.

Some respondents are interviewed at a time of personal anxiety. This group perceived their interview as having been influential because it made them reflect deeply on their situation, bringing their thoughts to bear when they conducted subsequent negotiations with partners. However, participants do not see this as a reason to avoid qualitative research. They describe themselves as agentic beings who felt ownership of their involvement in “Hard Labour 1”. Their approach make to reflect upon the author's interpretation of “safeguarding” which is now regarded as a concept which may be co‐constructed between researcher and participants.

The paper explores “safeguarding” in relation to the long‐term effects of qualitative research interviews. It is suggest that undertaking a reflexive reappraisal of research practices is important because analyses of past projects may (as in the author's case) result in a “shift” in understanding of research concepts from both an empirical and a theoretical perspective.