Da Vinci Institute

Estudiamos las famosas cúpulas de Leonardo Da Vinci, así como las variaciones concebidas por Rinus Roelofs, desde un punto de vista matemático. En particular, consideramos el problema de cerrar la cúpula para producir una estructura esférica. Explicamos por qué este problema está relacionado con consideraciones geométricas y topológicas sutiles. Esto contrasta con la estructura unidimensional análoga, a saber, el puente de Da Vinci, que se puede fácilmente continuar hasta cerrar una forma circular.

Orientation: There is a growing body of knowledge on the role of human resource (HR) professionals in workplace bullying, but their role in perpetuating a toxic leadership culture in organisations remains unscrutinised. Human resource professionals are uniquely positioned to influence toxic leadership styles as they are required to cultivate and sustain the organisational leadership culture.Research purpose: The aim of this study was to identify gaps in HR practices that could contribute to toxic leadership in organisations.Motivation of the study: The inherent role conflict of the HR professional and competing demands from organisational stakeholders are likely to create toxic outcomes.Research approach/design and method: A phenomenological study was carried out at a South African organisation to gain insight into the practices of HR professionals. Data were collected using semi-structured interviews and the key findings of the study were identified through a thematic analysis.Main findings: Three themes emerged that contribute to creating gaps in HR practices that support toxic leadership: toxic HR practices, challenges faced by HR professionals and business results at any cost.Practical/managerial implications: The findings suggest a need to alleviate the inherent role conflict experienced by HR professionals, so that their contributions to toxic leadership are minimised.Contribution/value-add: This study contributes to the literature on toxic leadership by expounding on the role of the human resources professionals (HRP) and gaps in their practices that contribute to toxic leadership. Suggested guidelines and recommendations are offered to address the gaps in HR practices.

<p>Environmental, Social, and Governance- ESG- an acronym coined in 2005, has been steadily growing until recently. Across industries, geographies, and company sizes, organisations have been allocating more resources toward improving ESG. Investors expect their assets to be a force for good, or at least not to harm. Approaches range from avoiding companies or sectors deemed to fail on ethical grounds to active engagement with companies. Exclusionary screening is the most prevalent approach to ESG investing and may focus on individual stocks or entire sectors. The environmental component of ESG and responses to climate change has driven a significant part of ESG growth. However, other components of ESG, particularly the social dimension, have also been gaining prominence. In the wake of the war in Ukraine, the ensuing human tragedy, and the cumulative geopolitical, economic, and societal effects, critics have argued that the importance of ESG has peaked. In the future, today’s preoccupation with ESG may be remembered as merely a fad and go the way of similar acronyms used in the past. This study explores the general concept of ESG in developing economies, its evolution and key components, and the importance and critical lens of ESG.</p>

The research aimed at identifying the organizational capabilities that influence the export performance of SMEs in Zimbabwe, as well as the strategies that can be adopted by SMEs to enhance their export performance. A mixed-methods study was carried out with a sample size of 345 SMEs in Harare, comprising food processing, leather products, and textiles and four (4) policy advocates and four (4) export business analysts. Questionnaires were directed at the SME owner-managers and an interview guide was used to collect qualitative data. The results reveal that, although distinctive capabilities play a pivotal role in enhancing the export performance of SMEs; its impact on Zimbabwean manufacturing SMEs is not significant. The findings are envisaged to provide insights on how SMEs in Zimbabwe can embrace organisational capabilities to enhance export performance.

The present examination explored the impact of 
 work spirituality and procedural justice on work locus of control, worker work fulfillment and representative authoritative duty among workers from private establishments of high learning in South Africa. Due to limited researches that have concentrated on the impact of workplace spirituality and procedural justice on work locus of control, employee job satisfaction and employee organisational commitment in developing countries especially in Southern Africa. A review was done and information was accumulated by methods for surveys on a sample of 150 academics and support staff in a private university setting in Gauteng, South Africa. Structural equation modelling was employed to analyse data using the Smart Partial Least Squares (PLS) software. By means of a partial least squares structural equation modeling approach, this study validates that elements such as workplace spirituality, procedural justice and work locus of control are instrumental in stimulating the employee job satisfaction and employee job commitment. The present investigation offers suggestions for academicians in the field of resource management by upgrading their comprehension of the how workplace spirituality and procedural justice impacts work locus of control, employee job satisfaction and employee organisational commitment

For pneumatic transport the basic principle of analysis is the material balance of the solids transported. A number of different situations could arise for the control of the solids flow. The macro approach to the control analysis will be considered first; then more detailed distributed models of the actual solids flow will be explored.

Flight vehicles of different sizes exhibit different responses to turbulence, particularly as a function of wingspan. This report exercises an Excel code, TURBANK, to calculate the stochastic bank characteristics of a vehicle excited by atmospheric turbulence. The lateral responses in ground level turbulence of ten representative vehicles, ranging in size from the 130 ft wingspan Boeing 707 through birds and small UAVs to a micro UAV of 1⁄2 ft wingspan, are calculated and discussed. Vehicles of less than one foot wingspan exhibit excessive bank response to turbulence. The code will be a tool for determining the factors involving lateral disturbances, which is a critically important flight characteristic for small UAVs.

When a bird or flight vehicle is oriented with a component of its lift vector aligned with the natural wind work is done on the flight system. Consequently, by suitable maneuvers, variations in wind speed can be used to add energy to the system. These procedures are used by albatrosses and many other birds. The equations of motion are simplified by normalizing using the minimum drag speed and integrating numerically for the control cycles involving angles of attack and bank. An energy neutral cycle by which an un-powered vehicle returns to initial velocity and height depends only upon the maximum lift/drag ratio of the vehicle and the wind speed variation. The minimum speed difference for a neutral energy cycle occurs for a vertical or horizontal step in wind speed. For a continuous wind profile a variational method is used to find the minimum gradient for a neutral energy cycle. Simple expressions are derived for the minimum wind variations for these two cases. The oceanic boundary layer and the shear layer downwind of a ridge are studied, and neutral energy wind criteria derived for them. Birds and small UAVs, with flight speeds comparable to atmospheric wind variations, can profit from wind energy extraction. Presented at the 43rd AIAA Aerospace Sciences Meeting and Exhibit, Reno NV, January, 10-13, 2005: Lissaman, P.B.S., “Wind Energy Extraction by Birds and Flight Vehicles,” AIAA Paper 2005-241, AIAA Annual Meeting, Reno, Jan. 2005.