Schalk Willem van der Merwe Meintjes, R.J. Huyssen and N.J. Theron
This paper argues that, together with improved protection structures and energy dissipation systems, a favourable occupant position with sufficient support and restraint could…
Abstract
This paper argues that, together with improved protection structures and energy dissipation systems, a favourable occupant position with sufficient support and restraint could reduce fatalities in aviation accidents. The crash responses of three different occupant positions were compared to justify the proposal of supporting a pilot in the rather unusual prone position. The normal seated and supine seated positions have already been adopted and implemented in aircraft. The occupant's response to specified crash pulse shapes in these two positions was compared with that of an occupant in the prone position. To obtain the best prone support configuration, different concepts were considered during the analysis. A dynamic event simulation program called ADAMS was used to perform the analysis, and existing injury criteria and a study of common causes of aviation fatalities and human body tolerance limits were used to compare the results. The study indicates that higher crash survivability in the prone position could be achieved if several guidelines are followed.
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A bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the theoretical…
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A bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the theoretical as well as practical points of view is given. The bibliography at the end of the paper contains 1,726 references to papers, conference proceedings and theses/dissertations dealing with the analysis of beams, columns, rods, bars, cables, discs, blades, shafts, membranes, plates and shells that were published in 1996‐1999.
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The simplest facet‐shell formulation involves the combination of the constant‐strain membrane triangle with a constant‐curvature bending triangle. The paper first describes an…
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The simplest facet‐shell formulation involves the combination of the constant‐strain membrane triangle with a constant‐curvature bending triangle. The paper first describes an alternative co‐rotational procedure to the one initially proposed by Peng and Crisfield in 1992. This new formulation introduces a spin matrix which allows a simpler formulation for the consistent tangent stiffness matrix. The paper then moves to the dynamics of the element. To obtain stable solutions, an energy‐conserving mid‐point time‐integration scheme is developed. This scheme exactly conserves the total energy when external forces are constant and when the physical system does not present any damping. The performance of this scheme is compared with other more conventional implicit schemes through a set of numerical examples involving large‐scale rotations.
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Since the 1990s, Charlize Theron has appeared in films from a wide range of genres but has seen significant financial success from starring in action films, such as Mad Max: Fury…
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Since the 1990s, Charlize Theron has appeared in films from a wide range of genres but has seen significant financial success from starring in action films, such as Mad Max: Fury Road (2015) and Atomic Blonde (2017). However, unlike some female action leads, she has not solely been defined or pigeonholed by these roles but has been able to transition between action roles and more ‘respectable’ dramatic roles, as well as the other conventions of female celebrity, such as being the face of advertising campaigns for perfume brands.
Theron has notably received several physical injuries during filming, such as breaking her teeth practising fight choreography during the production of Atomic Blonde. These injuries have frequently been added as part of the publicity campaign for the films and Theron's star image overall as signs of ‘authenticity’, leading these action films a sense of increased legitimacy. Tasker states that a female action star's ‘[public] formulation is indicative of the uncertainties generated by her image’ (1993, p. 14). Media attention is divided between focusing on Theron's physicality, both in the sense of the traditional Hollywood gaze and in terms of Theron's molding of her marketable image. Theron has managed to succeed as both a mainstream star and an action heroine. This has enabled Theron to transition between genres and franchises such as The Fate of The Furious (2017), and an Oscar-nominated dramatic role in the biopic Bombshell (2019).
This chapter will unpack the public persona of Charlize Theron as an action film star, exploring both the filmic texts and the presentation of Theron's often complicated and contradictory image in the media.
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The PMI Risk Framework (PRF) is introduced as a guide to classifying and identifying risks which can be the source of post-merger integration (PMI) failure — commonly referred to…
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The PMI Risk Framework (PRF) is introduced as a guide to classifying and identifying risks which can be the source of post-merger integration (PMI) failure — commonly referred to as “culture clash.” To provide managers with actionably insight, PRF dissects PMI risk into specific relationship-oriented phenomena, critical to outcomes and which should be addressed during PMI. This framework is a conceptual and theory-grounded integration of numerous perspectives, such as organizational psychology, group dynamics, social networks, transformational change, and nonlinear dynamics. These concepts are unified and can be acted upon by integration managers. Literary resources for further exploration into the underlying aspects of the framework are provided. The PRF places emphasis on critical facets of PMI, particularly those which are relational in nature, pose an exceptionally high degree of risk, and are recurrent sources of PMI failure. The chapter delves into relationship-oriented points of failure that managers face when overseeing PMI by introducing a relationship-based, PMI risk framework. Managers are often not fully cognizant of these risks, thus fail to manage them judiciously. These risks do not naturally abide by common scholarly classifications and cross disciplinary boundaries; they do not go unrecognized by scholars, but until the introduction of PRF the risks have not been assimilated into a unifying framework. This chapter presents a model of PMI risk by differentiating and specifying numerous types of underlying human-relationship-oriented risks, rather than considering PMI cultural conflict as a monolithic construct.
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Diwan U. Odendaal, Lelanie Smith, Kenneth J. Craig and Drewan S. Sanders
The purpose of this study is to re-evaluation fuselage design when the main wing’s has the ability to fulfill stability requirements without the need for a tailplane. The…
Abstract
Purpose
The purpose of this study is to re-evaluation fuselage design when the main wing’s has the ability to fulfill stability requirements without the need for a tailplane. The aerodynamic requirements of the fuselage usually involve a trade-off between reducing drag and providing enough length for positioning the empennage to ensure stability. However, if the main wing can fulfill the stability requirements without the need for a tailplane, then the fuselage design requirements can be re-evaluated. The optimisation of the fuselage can then include reducing drag and also providing a component of lift amongst other potential new requirements.
Design/methodology/approach
A careful investigation of parameterisation and trade-off optimisation methods to create such fuselage shapes was performed. The A320 Neo aircraft is optimised using a parameterised 3D fuselage model constructed with a modified PARSEC method and the SHERPA optimisation strategy, which was validated through three case studies. The geometry adjustments in relation to the specific flow phenomena are considered for the three optimal designs to investigate the influencing factors that should be considered for further optimisation.
Findings
The top three aerodynamic designs show a distinctive characteristic in the low aspect ratio thick wing-like aftbody that has pressure drag penalties, and the aftbody camber increased surface area notably improved the fuselage’s lift characteristics.
Originality/value
This work contributes to the development of a novel set of design requirements for a fuselage, free from the constraints imposed by stability requirements. By gaining insights into the flow phenomena that influence geometric designs when a lift requirement is introduced to the fuselage, we can understand how the fuselage configuration was optimised. This research lays the groundwork for identifying innovative design criteria that could extend into the integration of propulsion of the aftbody.
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Debra A. Noumair, Danielle L. Pfaff, Christine M. St. John, Asha N. Gipson and Sarah J. Brazaitis
The study of group dynamics was central to the field of organization development at its inception. More recently, there has been a move away from considering irrational and…
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The study of group dynamics was central to the field of organization development at its inception. More recently, there has been a move away from considering irrational and unconscious dynamics in organizational life and more attention focused on rational and observable behavior that can be measured and quantified. We introduce the tool, Beneath the Surface of the Burke-Litwin Model, that invites consideration of how the overt behavior of individuals, groups, and entire systems is linked to covert dynamics. This more comprehensive view of organizational life provides scholar-practitioners with a systemic perspective, a view of covert dynamics by organizational level, and support for the ongoing development of one’s capacity for using self-as-instrument when engaged in organization development and organization change efforts.
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Cheryl Hunter and Tsooane Molapo
This chapter examines the similarities and differences in teacher education between Botswana and Lesotho to unravel “best fit” strategies specific to the needs of teacher…
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This chapter examines the similarities and differences in teacher education between Botswana and Lesotho to unravel “best fit” strategies specific to the needs of teacher education in different locals or populations within these two countries. We begin with an overview of the social, political, and economic contexts of each country as a lens by which to understand some of the current challenges teachers face within each country. We review the research literature to understand what teacher preparation looks like at the tertiary level and how teachers in the field maintain current knowledge and pedagogical skills in regard the content they teach. We will argue that when teaching pedagogy at the tertiary level maintains an authoritarian model of teaching with content centered, didactic instruction, and teacher-centered pedagogy there is little ability for national change in education. Likewise, if teacher education does not embed the concept of life-long learning and is not supported by both a national and local commitment to support teacher’s continued professional development the ability to sustain any change in education is thwarted.